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  • 1.
    Ahmed, Engy
    et al.
    Stockholm Univ, Dept Geol Sci, SE-10691 Stockholm, Sweden.;Stockholm Univ, Bolin Ctr Climate Res, SE-10691 Stockholm, Sweden.;Sci Life Lab, Tomtebodavagen 23A, SE-17165 Solna, Sweden..
    Parducci, Laura
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och genetik, Växtekologi och evolution.
    Unneberg, Per
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för cell- och molekylärbiologi, Molekylär evolution.
    Ågren, Rasmus
    Chalmers Univ Technol, Dept Chem & Biol Engn, Sci Life Lab, SE-41296 Gothenburg, Sweden..
    Schenk, Frederik
    Stockholm Univ, Dept Geol Sci, SE-10691 Stockholm, Sweden.;Stockholm Univ, Bolin Ctr Climate Res, SE-10691 Stockholm, Sweden..
    Rattray, Jayne E.
    Stockholm Univ, Dept Geol Sci, SE-10691 Stockholm, Sweden.;Stockholm Univ, Bolin Ctr Climate Res, SE-10691 Stockholm, Sweden.;Univ Calgary, Biol Sci, 2500 Univ Dr NW, Calgary, AB, Canada..
    Han, Lu
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och genetik. Jilin Univ, Coll Life Sci, Ancient DNA Lab, Changchun, Jilin, Peoples R China..
    Muschitiello, Francesco
    Stockholm Univ, Dept Geol Sci, SE-10691 Stockholm, Sweden.;Stockholm Univ, Bolin Ctr Climate Res, SE-10691 Stockholm, Sweden.;Columbia Univ, Lamont Doherty Earth Observ, 61 Route 9NW, Palisades, NY USA..
    Pedersen, Mikkel W.
    Univ Cambridge, Dept Zool, Downing St, Cambridge CB2 3EJ, England..
    Smittenberg, Rienk H.
    Stockholm Univ, Dept Geol Sci, SE-10691 Stockholm, Sweden.;Stockholm Univ, Bolin Ctr Climate Res, SE-10691 Stockholm, Sweden..
    Yamoah, Kweku Afrifa
    Stockholm Univ, Dept Geol Sci, SE-10691 Stockholm, Sweden.;Stockholm Univ, Bolin Ctr Climate Res, SE-10691 Stockholm, Sweden..
    Slotte, Tanja
    Stockholm Univ, Dept Ecol Environm & Plant Sci, SE-10691 Stockholm, Sweden.;Sci Life Lab, Tomtebodavagen 23A, SE-17165 Solna, Sweden..
    Wohlfarth, Barbara
    Stockholm Univ, Dept Geol Sci, SE-10691 Stockholm, Sweden.;Stockholm Univ, Bolin Ctr Climate Res, SE-10691 Stockholm, Sweden..
    Archaeal community changes in Lateglacial lake sediments: Evidence from ancient DNA2018Ingår i: Quaternary Science Reviews, ISSN 0277-3791, E-ISSN 1873-457X, Vol. 181, s. 19-29Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The Lateglacial/early Holocene sediments from the ancient lake at Hasseldala Port, southern Sweden provide an important archive for the environmental and climatic shifts at the end of the last ice age and the transition into the present Interglacial. The existing multi-proxy data set highlights the complex interplay of physical and ecological changes in response to climatic shifts and lake status changes. Yet, it remains unclear how microorganisms, such as Archaea, which do not leave microscopic features in the sedimentary record, were affected by these climatic shifts. Here we present the metagenomic data set of Hasseldala Port with a special focus on the abundance and biodiversity of Archaea. This allows reconstructing for the first time the temporal succession of major Archaea groups between 13.9 and 10.8 ka BP by using ancient environmental DNA metagenomics and fossil archaeal cell membrane lipids. We then evaluate to which extent these findings reflect physical changes of the lake system, due to changes in lake-water summer temperature and seasonal lake-ice cover. We show that variations in archaeal composition and diversity were related to a variety of factors (e.g., changes in lake water temperature, duration of lake ice cover, rapid sediment infilling), which influenced bottom water conditions and the sediment-water interface. Methanogenic Archaea dominated during the Allerod and Younger Dryas pollen zones, when the ancient lake was likely stratified and anoxic for large parts of the year. The increase in archaeal diversity at the Younger Dryas/Holocene transition is explained by sediment infilling and formation of a mire/peatbog. (C) 2017 Elsevier Ltd. All rights reserved.

  • 2.
    Alneberg, Johannes
    et al.
    KTH Royal Inst Technol, Sch Engn Sci Chem Biotechnol & Hlth, Dept Gene Technol, Sci Life Lab, Stockholm, Sweden.
    Karlsson, Christofer M. G.
    Linnaeus Univ, Ctr Ecol & Evolut Microbial Model Syst, EEMiS, Kalmar, Sweden.
    Divne, Anna-Maria
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för cell- och molekylärbiologi, Molekylär evolution. Uppsala universitet, Science for Life Laboratory, SciLifeLab.
    Bergin, Claudia
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för cell- och molekylärbiologi, Molekylär evolution. Uppsala universitet, Science for Life Laboratory, SciLifeLab.
    Homa, Felix
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för cell- och molekylärbiologi, Molekylär evolution. Uppsala universitet, Science for Life Laboratory, SciLifeLab.
    Lindh, Markus V.
    Linnaeus Univ, Ctr Ecol & Evolut Microbial Model Syst, EEMiS, Kalmar, Sweden;Lund Univ, Dept Biol, Lund, Sweden.
    Hugerth, Luisa W.
    KTH Royal Inst Technol, Sch Engn Sci Chem Biotechnol & Hlth, Dept Gene Technol, Sci Life Lab, Stockholm, Sweden;Karolinska Inst, Ctr Translat Microbiome Res, Dept Mol Tumour & Cell Biol, Sci Life Lab, Solna, Sweden.
    Ettema, Thijs J. G.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för cell- och molekylärbiologi, Molekylär evolution. Uppsala universitet, Science for Life Laboratory, SciLifeLab.
    Bertilsson, Stefan
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och genetik, Limnologi. Uppsala universitet, Science for Life Laboratory, SciLifeLab.
    Andersson, Anders F.
    KTH Royal Inst Technol, Sch Engn Sci Chem Biotechnol & Hlth, Dept Gene Technol, Sci Life Lab, Stockholm, Sweden.
    Pinhassi, Jarone
    Linnaeus Univ, Ctr Ecol & Evolut Microbial Model Syst, EEMiS, Kalmar, Sweden.
    Genomes from uncultivated prokaryotes: a comparison of metagenome-assembled and single-amplified genomes2018Ingår i: Microbiome, ISSN 0026-2633, E-ISSN 2049-2618, Vol. 6, artikel-id 173Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Background: Prokaryotes dominate the biosphere and regulate biogeochemical processes essential to all life. Yet, our knowledge about their biology is for the most part limited to the minority that has been successfully cultured. Molecular techniques now allow for obtaining genome sequences of uncultivated prokaryotic taxa, facilitating in-depth analyses that may ultimately improve our understanding of these key organisms.

    Results: We compared results from two culture-independent strategies for recovering bacterial genomes: single-amplified genomes and metagenome-assembled genomes. Single-amplified genomes were obtained from samples collected at an offshore station in the Baltic Sea Proper and compared to previously obtained metagenome-assembled genomes from a time series at the same station. Among 16 single-amplified genomes analyzed, seven were found to match metagenome-assembled genomes, affiliated with a diverse set of taxa. Notably, genome pairs between the two approaches were nearly identical (average 99.51% sequence identity; range 98.77-99.84%) across overlapping regions (30-80% of each genome). Within matching pairs, the single-amplified genomes were consistently smaller and less complete, whereas the genetic functional profiles were maintained. For the metagenome-assembled genomes, only on average 3.6% of the bases were estimated to be missing from the genomes due to wrongly binned contigs.

    Conclusions: The strong agreement between the single-amplified and metagenome-assembled genomes emphasizes that both methods generate accurate genome information from uncultivated bacteria. Importantly, this implies that the research questions and the available resources are allowed to determine the selection of genomics approach for microbiome studies.

  • 3.
    Ameur, Adam
    et al.
    Uppsala universitet, Science for Life Laboratory, SciLifeLab. Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för immunologi, genetik och patologi. Natl Genom Infrastruct, Sci Life Lab, Stockholm, Sweden..
    Dahlberg, Johan
    Uppsala universitet, Science for Life Laboratory, SciLifeLab. Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för medicinska vetenskaper, Molekylär medicin. Natl Genom Infrastruct, Sci Life Lab, Stockholm, Sweden.
    Olason, Pall
    Uppsala universitet, Science for Life Laboratory, SciLifeLab. Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för cell- och molekylärbiologi. Natl Bioinformat Infrastruct, Sci Life Lab, Stockholm, Sweden..
    Vezzi, Francesco
    Natl Genom Infrastruct, Sci Life Lab, Stockholm, Sweden.;Stockholm Univ, Dept Biochem & Biophys, Sci Life Lab, Stockholm, Sweden..
    Karlsson, Robert
    Karolinska Inst, Dept Med Epidemiol & Biostat, Stockholm, Sweden..
    Martin, Marcel
    Natl Bioinformat Infrastruct, Sci Life Lab, Stockholm, Sweden.;Stockholm Univ, Dept Biochem & Biophys, Sci Life Lab, Stockholm, Sweden..
    Viklund, Johan
    Uppsala universitet, Science for Life Laboratory, SciLifeLab. Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för cell- och molekylärbiologi, Beräkningsbiologi och bioinformatik. Natl Bioinformat Infrastruct, Sci Life Lab, Stockholm, Sweden..
    Kähäri, Andreas
    Uppsala universitet, Science for Life Laboratory, SciLifeLab. Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för cell- och molekylärbiologi, Beräkningsbiologi och bioinformatik. Natl Bioinformat Infrastruct, Sci Life Lab, Stockholm, Sweden..
    Lundin, Par
    Stockholm Univ, Dept Biochem & Biophys, Sci Life Lab, Stockholm, Sweden..
    Che, Huiwen
    Uppsala universitet, Science for Life Laboratory, SciLifeLab. Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för immunologi, genetik och patologi.
    Thutkawkorapin, Jessada
    Karolinska Inst, Dept Mol Med & Surg, Stockholm, Sweden..
    Eisfeldt, Jesper
    Karolinska Inst, Dept Mol Med & Surg, Stockholm, Sweden..
    Lampa, Samuel
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Farmaceutiska fakulteten, Institutionen för farmaceutisk biovetenskap. Natl Bioinformat Infrastruct, Sci Life Lab, Stockholm, Sweden.
    Dahlberg, Mats
    Natl Bioinformat Infrastruct, Sci Life Lab, Stockholm, Sweden.;Stockholm Univ, Dept Biochem & Biophys, Sci Life Lab, Stockholm, Sweden..
    Hagberg, Jonas
    Natl Bioinformat Infrastruct, Sci Life Lab, Stockholm, Sweden.;Stockholm Univ, Dept Biochem & Biophys, Sci Life Lab, Stockholm, Sweden..
    Jareborg, Niclas
    Natl Bioinformat Infrastruct, Sci Life Lab, Stockholm, Sweden.;Stockholm Univ, Dept Biochem & Biophys, Sci Life Lab, Stockholm, Sweden..
    Liljedahl, Ulrika
    Uppsala universitet, Science for Life Laboratory, SciLifeLab. Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för medicinska vetenskaper, Molekylär medicin. Natl Genom Infrastruct, Sci Life Lab, Stockholm, Sweden.
    Jonasson, Inger
    Uppsala universitet, Science for Life Laboratory, SciLifeLab. Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för immunologi, genetik och patologi. Natl Genom Infrastruct, Sci Life Lab, Stockholm, Sweden..
    Johansson, Åsa
    Uppsala universitet, Science for Life Laboratory, SciLifeLab. Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för immunologi, genetik och patologi, Medicinsk genetik och genomik.
    Feuk, Lars
    Uppsala universitet, Science for Life Laboratory, SciLifeLab. Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för immunologi, genetik och patologi, Medicinsk genetik och genomik.
    Lundeberg, Joakim
    Natl Genom Infrastruct, Sci Life Lab, Stockholm, Sweden.;Royal Inst Technol, Div Gene Technol, Sch Biotechnol, Sci Life Lab, Stockholm, Sweden..
    Syvänen, Ann-Christine
    Uppsala universitet, Science for Life Laboratory, SciLifeLab. Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för medicinska vetenskaper, Molekylär medicin. Natl Genom Infrastruct, Sci Life Lab, Stockholm, Sweden.
    Lundin, Sverker
    Royal Inst Technol, Div Gene Technol, Sch Biotechnol, Sci Life Lab, Stockholm, Sweden..
    Nilsson, Daniel
    Karolinska Inst, Dept Mol Med & Surg, Stockholm, Sweden..
    Nystedt, Björn
    Uppsala universitet, Science for Life Laboratory, SciLifeLab. Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för cell- och molekylärbiologi, Molekylär evolution. Natl Bioinformat Infrastruct, Sci Life Lab, Stockholm, Sweden..
    Magnusson, Patrik K. E.
    Natl Genom Infrastruct, Sci Life Lab, Stockholm, Sweden.;Karolinska Inst, Dept Med Epidemiol & Biostat, Stockholm, Sweden..
    Gyllensten, Ulf B.
    Uppsala universitet, Science for Life Laboratory, SciLifeLab. Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för immunologi, genetik och patologi, Medicinsk genetik och genomik.
    SweGen: a whole-genome data resource of genetic variability in a cross-section of the Swedish population2017Ingår i: European Journal of Human Genetics, ISSN 1018-4813, E-ISSN 1476-5438, Vol. 25, nr 11, s. 1253-1260Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Here we describe the SweGen data set, a comprehensive map of genetic variation in the Swedish population. These data represent a basic resource for clinical genetics laboratories as well as for sequencing-based association studies by providing information on genetic variant frequencies in a cohort that is well matched to national patient cohorts. To select samples for this study, we first examined the genetic structure of the Swedish population using high-density SNP-array data from a nation-wide cohort of over 10 000 Swedish-born individuals included in the Swedish Twin Registry. A total of 1000 individuals, reflecting a cross-section of the population and capturing the main genetic structure, were selected for whole-genome sequencing. Analysis pipelines were developed for automated alignment, variant calling and quality control of the sequencing data. This resulted in a genome-wide collection of aggregated variant frequencies in the Swedish population that we have made available to the scientific community through the website https://swefreq.nbis.se. A total of 29.2 million single-nucleotide variants and 3.8 million indels were detected in the 1000 samples, with 9.9 million of these variants not present in current databases. Each sample contributed with an average of 7199 individual-specific variants. In addition, an average of 8645 larger structural variants (SVs) were detected per individual, and we demonstrate that the population frequencies of these SVs can be used for efficient filtering analyses. Finally, our results show that the genetic diversity within Sweden is substantial compared with the diversity among continental European populations, underscoring the relevance of establishing a local reference data set.

  • 4.
    Andersson, Jan O
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för cell- och molekylärbiologi, Molekylär evolution. Uppsala universitet, Science for Life Laboratory, SciLifeLab.
    Double peaks reveal rare diplomonad sex2012Ingår i: Trends in Parasitology, ISSN 1471-4922, E-ISSN 1471-5007, Vol. 28, nr 2, s. 46-52Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Diplomonads, single-celled eukaryotes, are unusual in having two nuclei. Each nucleus contains two copies of the genome and is transcriptionally active. It has long been assumed that diplomonads in general and Giardia intestinalis in particular are asexual. Genomic and population genetic data now challenge that assumption and extensive allelic sequence heterogeneity has been reported in some but not all examined diplomonad lineages. Here it is argued, in contrast to common assumptions, that allelic differences indicate recent sexual events, and isolates that have divided asexually for many generations have lost their allelic variation owing to within-cell recombination. Consequently, directed studies of the allelic sequence heterogeneity in diverse diplomonad lineages are likely to reveal details about the enigmatic diplomonad sexual life cycle.

  • 5.
    Andersson, Jan O
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för cell- och molekylärbiologi, Molekylär evolution.
    Evolution of Patchily Distributed Proteins Shared between Eukaryotes and Prokaryotes: Dictyostelium as a Case Study2011Ingår i: Journal of Molecular Biology and Biotechnology, ISSN 1464-1801, E-ISSN 1660-2412, Vol. 20, nr 2, s. 83-95Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Protein families are often patchily distributed in the tree of life; they are present in distantly related organisms, but absent in more closely related lineages. This could either be the result of lateral gene transfer between ancestors of organisms that encode them, or losses in the lineages that lack them. Here a novel approach is developed to study the evolution of patchily distributed proteins shared between prokaryotes and eukaryotes. Proteins encoded in the genome of cellular slime mold Dictyostelium discoideum and a restricted number of other lineages, including at least one prokaryote, were identified. Analyses of the phylogenetic distribution of 49 such patchily distributed protein families showed conflicts with organismal phylogenies; 25 are shared with the distantly related amoeboflagellate Naegleria (Excavata), whereas only two are present in the more closely related Entamoeba. Most protein families show unexpected topologies in phylogenetic analyses; eukaryotes are polyphyletic in 85% of the trees. These observations suggest that gene transfers have been an important mechanism for the distribution of patchily distributed proteins across all domains of life. Further studies of this exchangeable gene fraction are needed for a better understanding of the origin and evolution of eukaryotic genes and the diversification process of eukaryotes.

  • 6.
    Andersson, Jan O.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för organismbiologi, Molekylär evolution.
    Gene Transfer and Diversification of Microbial Eukaryotes2009Ingår i: Annual Review of Microbiology, ISSN 0066-4227, E-ISSN 1545-3251, Vol. 63, s. 177-193Artikel, forskningsöversikt (Refereegranskat)
    Abstract [en]

    The importance of lateral gene transfer in genome evolution of microbial eukaryotes is slowly being appreciated. Acquisitions of genes have led to metabolic adaptation in diverse eukaryotic lineages. In most cases the metabolic genes have originated from prokaryotes, often followed by sequential transfers between eukaryotes. However, the knowledge of gene transfer in eukaryotes is still mainly based on anecdotal evidence. Some of the observed patterns may be biases in experimental approaches and sequence databases rather than evolutionary trends. Rigorous systematic studies of gene acquisitions that allow for the possibility of exchanges of all categories of genes from all sources are needed to get a more objective view of gene transfer in eukaryote evolution. It it-lay be that the role of gene transfer in the diversification process of microbial eukaryotes currently is underestimated.

  • 7.
    Andersson, Jan O
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för cell- och molekylärbiologi, Molekylär evolution.
    Gene Transfer and the Chimeric Nature of Eukaryotic Genomes2013Ingår i: Lateral Gene Transfer in Evolution / [ed] Uri Gophna, New York: Springer Science+Business Media B.V., 2013, s. 181-197Kapitel i bok, del av antologi (Övrigt vetenskapligt)
  • 8.
    Andersson, Jan O.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för cell- och molekylärbiologi, Molekylär evolution.
    Horizontal gene transfer between microbial eukaryotes.2009Ingår i: Methods in Molecular Biology, ISSN 1064-3745, E-ISSN 1940-6029, Vol. 532, nr 4, s. 473-487Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Comparative genomics have identified two loosely defined classes of genes: widely distributed core genes that encode proteins for central functions in the cell and accessory genes that are patchily distributed across lineages and encode taxa-specific functions. Studies of microbial eukaryotes show that both categories undergo horizontal gene transfer (HGT) from prokaryotes, but also between eukaryotic organisms. Intra-domain gene transfers of most core genes seem to be relatively infrequent and therefore comparatively easy to detect using phylogenetic methods. In contrast, phylogenies of accessory genes often have complex topologies with little or no resemblance of organismal relationships typically with eukaryotes and prokaryotes intermingled, making detailed evolutionary histories difficult to interpret. Nevertheless, this suggests significant rates of gene transfer between and among the three domains of life for many of these genes, affecting a considerably diversity of eukaryotic microbes, although the current depth of taxonomic sampling usually is insufficient to pin down individual transfer events. The occurrence of intra-domain transfer among microbial eukaryotes has important implications for studies of organismal phylogeny as well as eukaryote genome evolution in general.

  • 9.
    Andersson, Jan O
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för cell- och molekylärbiologi, Molekylär evolution. Uppsala universitet, Science for Life Laboratory, SciLifeLab.
    Phylogenomic approaches underestimate eukaryotic gene transfer2012Ingår i: Mobile Genetic Elements, Vol. 2, nr 1, s. 59-62Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Phylogenomic approaches have shown that eukaryotes acquire genes via gene transfer. However, there are two fundamental problems for most of these analyses; only transfers from prokaryotes are analyzed and the screening procedures applied assume that gene transfer is rare for eukaryotes. Directed studies of the impact of gene transfer on diverse eukaryotic lineages produce a much more complex picture. Many gene families are affected by multiple transfer events from prokaryotes to eukaryotes, and transfers between eukaryotic lineages are routinely detected. This suggests that the assumptions applied in traditional phylogenomic approaches are too naïve and result in many false negatives. This issue was recently addressed by identifying and analyzing the evolutionary history of 49 patchily distributed proteins shared between Dictyostelium and bacteria. The vast majority of these gene families showed strong indications of gene transfers, both between and within the three domains of life. However, only one of these was previously reported as a gene transfer candidate using a traditional phylogenomic approach. This clearly illustrates that more realistic assumptions are urgently needed in genome-wide studies of eukaryotic gene transfer.

  • 10.
    Andersson, Jan O.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för cell- och molekylärbiologi, Molekylär evolution.
    The New Foundations of Evolution: On the Tree of Life2011Ingår i: Systematic Biology, ISSN 1063-5157, E-ISSN 1076-836X, Vol. 60, nr 1, s. 114-115Artikel, recension (Övrig (populärvetenskap, debatt, mm))
  • 11.
    Andersson, Jan O
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för cell- och molekylärbiologi, Molekylär evolution.
    Andersson, Siv GE
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för cell- och molekylärbiologi, Molekylär evolution.
    A century of typhus, lice and Rickettsia2000Ingår i: Research in Microbiology, ISSN 0923-2508, E-ISSN 1769-7123, Vol. 151, nr 2, s. 143-150Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    At the beginning of the 20th century, it was discovered at the Pasteur Institute in Tunis that epidemic typhus is transmitted by the human body louse. The complete genome sequence of its causative agent, Rickettsia prowazekii, was determined at Uppsala University in Sweden at the end of the century. In this mini-review, we discuss insights gained from the genome sequence of this fascinating and deadly organism.

  • 12.
    Andersson, Jan O.
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för organismbiologi, Molekylär evolution.
    Jerlström-Hultqvist, Jon
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för cell- och molekylärbiologi, Mikrobiologi.
    Svärd, Staffan G.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för cell- och molekylärbiologi, Mikrobiologi.
    The genome of Giardia and other diplomonads2010Ingår i: Anaerobic Parasitic Protozoa: Genomics and Molecular Biology / [ed] C. Graham Clark, Patricia J. Johnson, Rodney D. Adam, Caister Academic Press , 2010, s. 23-44Kapitel i bok, del av antologi (Övrigt vetenskapligt)
  • 13.
    Andersson, Siv G. E.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för cell- och molekylärbiologi, Molekylär evolution.
    Stress management strategies in single bacterial cells2016Ingår i: Proceedings of the National Academy of Sciences of the United States of America, ISSN 0027-8424, E-ISSN 1091-6490, Vol. 113, nr 15, s. 3921-3923Artikel i tidskrift (Övrigt vetenskapligt)
  • 14.
    Andersson, Siv G. E.
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för cell- och molekylärbiologi, Molekylär evolution.
    Goodman, A. L.
    Bacterial genomes: Next generation sequencing technologies for studies of bacterial ecosystems2012Ingår i: Current Opinion in Microbiology, ISSN 1369-5274, E-ISSN 1879-0364, Vol. 15, nr 5, s. 603-604Artikel i tidskrift (Övrigt vetenskapligt)
  • 15.
    Ankarklev, Johan
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för cell- och molekylärbiologi. Uppsala universitet, Science for Life Laboratory, SciLifeLab.
    Franzen, Oscar
    Karolinska Inst, Dept Cell & Mol Biol, SE-17177 Stockholm, Sweden. KISP, Sci Life Lab, S-17165 Solna, Sweden..
    Peirasmaki, Dimitra
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för cell- och molekylärbiologi, Mikrobiologi. Uppsala universitet, Science for Life Laboratory, SciLifeLab.
    Jerlstrom-Hultqvist, Jon
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för cell- och molekylärbiologi. Uppsala universitet, Science for Life Laboratory, SciLifeLab.
    Lebbad, Marianne
    Publ Hlth Agcy Sweden, Dept Microbiol, SE-17182 Solna, Sweden..
    Andersson, Jan
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för cell- och molekylärbiologi, Molekylär evolution. Uppsala universitet, Science for Life Laboratory, SciLifeLab.
    Andersson, Bjorn
    Karolinska Inst, Dept Cell & Mol Biol, SE-17177 Stockholm, Sweden.;KISP, Sci Life Lab, S-17165 Solna, Sweden..
    Svärd, Staffan G.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för cell- och molekylärbiologi, Mikrobiologi. Uppsala universitet, Science for Life Laboratory, SciLifeLab.
    Comparative genomic analyses of freshly isolated Giardia intestinalis assemblage A isolates2015Ingår i: BMC Genomics, ISSN 1471-2164, E-ISSN 1471-2164, Vol. 16, artikel-id 697Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Background: The diarrhea-causing protozoan Giardia intestinalis makes up a species complex of eight different assemblages (A-H), where assemblage A and B infect humans. Comparative whole-genome analyses of three of these assemblages have shown that there is significant divergence at the inter-assemblage level, however little is currently known regarding variation at the intra-assemblage level. We have performed whole genome sequencing of two sub-assemblage AII isolates, recently axenized from symptomatic human patients, to study the biological and genetic diversity within assemblage A isolates. Results: Several biological differences between the new and earlier characterized assemblage A isolates were identified, including a difference in growth medium preference. The two AII isolates were of different sub-assemblage types (AII-1 [AS175] and AII-2 [AS98]) and showed size differences in the smallest chromosomes. The amount of genetic diversity was characterized in relation to the genome of the Giardia reference isolate WB, an assemblage AI isolate. Our analyses indicate that the divergence between AI and AII is approximately 1 %, represented by similar to 100,000 single nucleotide polymorphisms (SNP) distributed over the chromosomes with enrichment in variable genomic regions containing surface antigens. The level of allelic sequence heterozygosity (ASH) in the two AII isolates was found to be 0.25-0.35 %, which is 25-30 fold higher than in the WB isolate and 10 fold higher than the assemblage AII isolate DH (0.037 %). 35 protein-encoding genes, not found in the WB genome, were identified in the two AII genomes. The large gene families of variant-specific surface proteins (VSPs) and high cysteine membrane proteins (HCMPs) showed isolate-specific divergences of the gene repertoires. Certain genes, often in small gene families with 2 to 8 members, localize to the variable regions of the genomes and show high sequence diversity between the assemblage A isolates. One of the families, Bactericidal/ Permeability Increasing-like protein (BPIL), with eight members was characterized further and the proteins were shown to localize to the ER in trophozoites. Conclusions: Giardia genomes are modular with highly conserved core regions mixed up by variable regions containing high levels of ASH, SNPs and variable surface antigens. There are significant genomic variations in assemblage A isolates, in terms of chromosome size, gene content, surface protein repertoire and gene polymorphisms and these differences mainly localize to the variable regions of the genomes. The large genetic differences within one assemblage of G. intestinalis strengthen the argument that the assemblages represent different Giardia species.

  • 16.
    Ankarklev, Johan
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för cell- och molekylärbiologi, Mikrobiologi.
    Hestvik, Elin
    Lebbad, Marianne
    Lindh, Johan
    Kaddu-Mulindwa, Deogratias H.
    Andersson, Jan O.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för cell- och molekylärbiologi, Molekylär evolution.
    Tylleskar, Thorkild
    Tumwine, James K.
    Svärd, Staffan G.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för cell- och molekylärbiologi, Mikrobiologi.
    Common Coinfections of Giardia intestinalis and Helicobacter pylori in Non-Symptomatic Ugandan Children2012Ingår i: PLOS Neglected Tropical Diseases, ISSN 1935-2735, Vol. 6, nr 8, s. e1780-Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Background: The protozoan parasite Giardia intestinalis and the pathogenic bacterium Helicobacter pylori are well known for their high prevalences in human hosts worldwide. The prevalence of both organisms is known to peak in densely populated, low resource settings and children are infected early in life. Different Giardia genotypes/assemblages have been associated with different symptoms and H. pylori with induction of cancer. Despite this, not much data are available from sub-Saharan Africa with regards to the prevalence of different G. intestinalis assemblages and their potential association with H. pylori infections.

    Methodology/Principal Findings: Fecal samples from 427 apparently healthy children, 0-12 years of age, living in urban Kampala, Uganda were analyzed for the presence of H. pylori and G. intestinalis. G. intestinalis was found in 86 (20.1%) out of the children and children age 1<5 years had the highest rates of colonization. H. pylori was found in 189 (44.3%) out of the 427 children and there was a 3-fold higher risk of concomitant G. intestinalis and H. pylori infections compared to non-concomitant G. intestinalis infection, OR = 2.9 (1.7-4.8). No significant association was found in the studied population with regard to the presence of Giardia and gender, type of toilet, source of drinking water or type of housing. A panel of 45 G. intestinalis positive samples was further analyzed using multi-locus genotyping (MLG) on three loci, combined with assemblage-specific analyses. Giardia MLG analysis yielded a total of five assemblage AII, 25 assemblage B, and four mixed assemblage infections. The assemblage B isolates were highly genetically variable but no significant association was found between Giardia assemblage type and H. pylori infection.

    Conclusions/Significance: This study shows that Giardia assemblage B dominates in children in Kampala, Uganda and that the presence of H. pylori is an associated risk factor for G. intestinalis infection.

  • 17.
    Astvaldsson, Asgeir
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för cell- och molekylärbiologi, Mikrobiologi. Uppsala universitet, Science for Life Laboratory, SciLifeLab.
    Stairs, Courtney W.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för cell- och molekylärbiologi, Molekylär evolution. Uppsala universitet, Science for Life Laboratory, SciLifeLab.
    Xu, Feifei
    Uppsala universitet, Science for Life Laboratory, SciLifeLab. Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för cell- och molekylärbiologi, Molekylär evolution.
    Haag, Lars
    Alfjorden, Anders
    Jansson, Eva
    Ettema, Thijs
    Svärd, Staffan
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för cell- och molekylärbiologi, Mikrobiologi. Uppsala universitet, Science for Life Laboratory, SciLifeLab.
    Dual transcriptomic analysis of Spironucleus salmonicida-infected salmon cells identifies putative virulence factors and host responsesManuskript (preprint) (Övrigt vetenskapligt)
  • 18.
    Baiao, Guilherme Costa
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för cell- och molekylärbiologi, Molekylär evolution. Swedish Museum Nat Hist, Dept Zool, Stockholm, Sweden.
    Forshage, Mattias
    Swedish Museum Nat Hist, Dept Zool, Stockholm, Sweden.
    Revision of the West Palaearctic species of Rhoptromeris Forster, 1869 (Hymenoptera: Figitidae: Eucoilinae)2018Ingår i: Journal of Natural History, ISSN 0022-2933, E-ISSN 1464-5262, Vol. 52, nr 17-18, s. 1201-1224Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The West Palearctic species of Rhoptromeris are revised. A total of 11 species are recognised as valid in this region, including four newly described species: Rhoptromeris dichromata sp. nov., Rhoptromeris koponeni sp. nov., Rhoptromeris leptocornis sp. nov. and Rhoptromeris macaronesiensis sp. nov. Eucoila luteicornis Ionescu, 1959 is synonymised with Rhoptromeris heptoma (Hartig, 1840) syn. nov. A checklist of the Holarctic Rhoptromeris is presented and an identification key to the West Palearctic species is provided.

    www.zoobank.org/urn:lsid:zoobank.org:pub:8164332C-93E2-4E3F-A408-F5FF5DFB366E

  • 19.
    Baiao, Guilherme Costa
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för cell- och molekylärbiologi, Molekylär evolution.
    Schneider, Daniela I.
    Med Univ Vienna, Ctr Anat & Cell Biol, Lab Genome Dynam, Deparment Cell & Dev Biol, Schwarzspanierstr 17, A-1090 Vienna, Austria;Yale Univ, Dept Epidemiol Microbial Dis, 60 Coll St, New Haven, CT 06510 USA.
    Miller, Wolfgang J.
    Med Univ Vienna, Ctr Anat & Cell Biol, Lab Genome Dynam, Deparment Cell & Dev Biol, Schwarzspanierstr 17, A-1090 Vienna, Austria.
    Klasson, Lisa
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för cell- och molekylärbiologi, Molekylär evolution.
    The effect of Wolbachia on gene expression in Drosophila paulistorum and its implications for symbiont-induced host speciation2019Ingår i: BMC Genomics, ISSN 1471-2164, E-ISSN 1471-2164, Vol. 20, artikel-id 465Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Background: The Neotropical fruit fly Drosophila paulistorum (Diptera: Drosophilidae) is a species complex in statu nascendi comprising six reproductively isolated semispecies, each harboring mutualistic Wolbachia strains. Although wild type flies of each semispecies are isolated from the others by both pre- and postmating incompatibilities, mating between semispecies and successful offspring development can be achieved once flies are treated with antibiotics to reduce Wolbachia titer. Here we use RNA-seq to study the impact of Wolbachia on D. paulistorum and investigate the hypothesis that the symbiont may play a role in host speciation. For that goal, we analyze samples of heads and abdomens of both sexes of the Amazonian, Centro American and Orinocan semispecies of D. paulistorum.

    Results: We identify between 175 and 1192 differentially expressed genes associated with a variety of biological processes that respond either globally or according to tissue, sex or condition in the three semispecies. Some of the functions associated with differentially expressed genes are known to be affected by Wolbachia in other species, such as metabolism and immunity, whereas others represent putative novel phenotypes involving muscular functions, pheromone signaling, and visual perception.

    Conclusions: Our results show that Wolbachia affect a large number of biological functions in D. paulistorum, particularly when present in high titer. We suggest that the significant metabolic impact of the infection on the host may cause several of the other putative and observed phenotypes. We also speculate that the observed differential expression of genes associated with chemical communication and reproduction may be associated with the emergence of pre- and postmating barriers between semispecies, which supports a role for Wolbachia in the speciation of D. paulistorum.

  • 20.
    Baker, Brett J.
    et al.
    Univ Texas Austin, Inst Marine Sci, Dept Marine Sci, Port Aransas, TX 78373 USA..
    Saw, Jimmy H.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för cell- och molekylärbiologi. Uppsala universitet, Science for Life Laboratory, SciLifeLab.
    Lind, Anders E.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för cell- och molekylärbiologi, Molekylär evolution. Uppsala universitet, Science for Life Laboratory, SciLifeLab.
    Lazar, Cassandre Sara
    Univ Bremen, MARUM Ctr Marine Environm Sci, Bremen, Germany..
    Hinrichs, Kai-Uwe
    Univ Bremen, MARUM Ctr Marine Environm Sci, Bremen, Germany..
    Teske, Andreas P.
    Univ N Carolina, Dept Marine Sci, Chapel Hill, NC 27599 USA..
    Ettema, Thijs J. G.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för cell- och molekylärbiologi, Molekylär evolution. Uppsala universitet, Science for Life Laboratory, SciLifeLab.
    Genomic inference of the metabolism of cosmopolitan subsurface Archaea, Hadesarchaea2016Ingår i: Nature Microbiology, E-ISSN 2058-5276, Vol. 1, nr 3, artikel-id 16002Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The subsurface biosphere is largely unexplored and contains a broad diversity of uncultured microbes(1). Despite being one of the few prokaryotic lineages that is cosmopolitan in both the terrestrial and marine subsurface(2-4), the physiological and ecological roles of SAGMEG (South-African Gold Mine Miscellaneous Euryarchaeal Group) Archaea are unknown. Here, we report the metabolic capabilities of this enigmatic group as inferred from genomic reconstructions. Four high-quality (63-90% complete) genomes were obtained from White Oak River estuary and Yellowstone National Park hot spring sediment metagenomes. Phylogenomic analyses place SAGMEG Archaea as a deeply rooting sister clade of the Thermococci, leading us to propose the name Hadesarchaea for this new Archaeal class. With an estimated genome size of around 1.5 Mbp, the genomes of Hadesarchaea are distinctly streamlined, yet metabolically versatile. They share several physiological mechanisms with strict anaerobic Euryarchaeota. Several metabolic characteristics make them successful in the subsurface, including genes involved in CO and H-2 oxidation (or H-2 production), with potential coupling to nitrite reduction to ammonia (DNRA). This first glimpse into the metabolic capabilities of these cosmopolitan Archaea suggests they are mediating key geochemical processes and are specialized for survival in the subsurface biosphere.

  • 21.
    Bartoschek, Michael
    et al.
    Lund Univ, Dept Lab Med, Div Translat Canc Res, BioCARE, S-22381 Lund, Sweden.
    Oskolkov, Nikolay
    Lund Univ, Sci Life Lab, Natl Bioinformat Infrastruct Sweden, Dept Biol, Solvegatan 35, S-22362 Lund, Sweden.
    Bocci, Matteo
    Lund Univ, Dept Lab Med, Div Translat Canc Res, BioCARE, S-22381 Lund, Sweden.
    Lovrot, John
    Karolinska Inst, Dept Oncol & Pathol, Karolinska Univ Sjukhuset Z1 01, S-17176 Stockholm, Sweden.
    Larsson, Christer
    Lund Univ, Dept Lab Med, Div Translat Canc Res, BioCARE, S-22381 Lund, Sweden.
    Sommarin, Mikael
    Lund Univ, Lund Stem Cell Ctr, Div Mol Hematol, BMC B12, S-22184 Lund, Sweden.
    Madsen, Chris D.
    Lund Univ, Dept Lab Med, Div Translat Canc Res, BioCARE, S-22381 Lund, Sweden.
    Lindgren, David
    Lund Univ, Dept Lab Med, Div Translat Canc Res, BioCARE, S-22381 Lund, Sweden.
    Pekar, Gyula
    Lund Univ, Dept Clin Sci, Div Oncol & Pathol, Skane Univ Hosp, S-22185 Lund, Sweden.
    Karlsson, Goran
    Lund Univ, Lund Stem Cell Ctr, Div Mol Hematol, BMC B12, S-22184 Lund, Sweden.
    Ringner, Markus
    Lund Univ, Sci Life Lab, Natl Bioinformat Infrastruct Sweden, Dept Biol, Solvegatan 35, S-22362 Lund, Sweden.
    Bergh, Jonas
    Karolinska Inst, Dept Oncol & Pathol, Karolinska Univ Sjukhuset Z1 01, S-17176 Stockholm, Sweden.
    Björklund, Åsa
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för cell- och molekylärbiologi, Molekylär evolution. Uppsala universitet, Science for Life Laboratory, SciLifeLab.
    Pietras, Kristian
    Lund Univ, Dept Lab Med, Div Translat Canc Res, BioCARE, S-22381 Lund, Sweden.
    Spatially and functionally distinct subclasses of breast cancer-associated fibroblasts revealed by single cell RNA sequencing2018Ingår i: Nature Communications, ISSN 2041-1723, E-ISSN 2041-1723, Vol. 9, artikel-id 5150Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Cancer-associated fibroblasts (CAFs) are a major constituent of the tumor microenvironment, although their origin and roles in shaping disease initiation, progression and treatment response remain unclear due to significant heterogeneity. Here, following a negative selection strategy combined with single-cell RNA sequencing of 768 transcriptomes of mesenchymal cells from a genetically engineered mouse model of breast cancer, we define three distinct subpopulations of CAFs. Validation at the transcriptional and protein level in several experimental models of cancer and human tumors reveal spatial separation of the CAF subclasses attributable to different origins, including the peri-vascular niche, the mammary fat pad and the transformed epithelium. Gene profiles for each CAF subtype correlate to distinctive functional programs and hold independent prognostic capability in clinical cohorts by association to metastatic disease. In conclusion, the improved resolution of the widely defined CAF population opens the possibility for biomarker-driven development of drugs for precision targeting of CAFs.

  • 22.
    Beier, Sara
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och genetik, Limnologi.
    Mohit, Vani
    Département de Biologie, Québec-Océan and Institut de biologie integrative et des systèmes, Université Laval.
    Ettema, Thijs J. G.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för cell- och molekylärbiologi, Molekylär evolution.
    Östman, Örjan
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och genetik, Populationsbiologi och naturvårdsbiologi.
    Tranvik, Lars J.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och genetik, Limnologi.
    Bertilsson, Stefan
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och genetik, Limnologi.
    Pronounced seasonal dynamics of freshwater chitinase genes and chitin processing2012Ingår i: Environmental Microbiology, ISSN 1462-2912, E-ISSN 1462-2920, Vol. 14, nr 9, s. 2467-2479Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Seasonal variation in activity of enzymes involved in polymer degradation, including chitinases, has been observed previously in freshwater environments. However, it is not known whether the seasonal dynamics are due to shifts in the activity of bacteria already present, or shifts in community structure towards emergence or disappearance of chitinolytic organisms. We traced seasonal shifts in the chitinase gene assemblage in a temperate lake and linked these communities to variation in chitinase activity. Chitinase genes from 20 samples collected over a full yearly cycle were characterized by pyrosequencing. Pronounced temporal shifts in composition of the chitinase gene pool (beta diversity) occurred along with distinct shifts in richness (alpha diversity) as well as chitin processing. Changes in the chitinase gene pool correlated mainly with temperature, abundance of crustacean zooplankton and phytoplankton blooms. Also changes in the physical structure of the lake, e.g. stratification and mixing were associated with changes in the chitinolytic community, while differences were minor between surface and suboxic hypolimnetic water. The lake characteristics influencing the chitinolytic community are all linked to changes in organic particles and we suggest that seasonal changes in particle quality and availability foster microbial communities adapted to efficiently degrade them.

  • 23.
    Bergin, Claudia
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för cell- och molekylärbiologi, Molekylär evolution. Uppsala universitet, Science for Life Laboratory, SciLifeLab. Max Planck Inst Marine Mikrobiol, Bremen, Germany.
    Wentrup, C.
    Max Planck Inst Marine Mikrobiol, Bremen, Germany.;Univ Vienna, Div Microbial Ecol, Dept Microbiol & Ecosyst Sci, Vienna, Austria..
    Brewig, N.
    Max Planck Inst Marine Mikrobiol, Bremen, Germany..
    Blazejak, A.
    Max Planck Inst Marine Mikrobiol, Bremen, Germany..
    Erseus, C.
    Univ Gothenburg, Dept Biol & Environm Sci, Gothenburg, Sweden..
    Giere, O.
    Univ Hamburg, Biozentrum Grindel, Zool Inst, Hamburg, Germany.;Univ Hamburg, Zool Museum, Hamburg, Germany..
    Schmid, M.
    Univ Vienna, Div Microbial Ecol, Dept Microbiol & Ecosyst Sci, Vienna, Austria..
    De Wit, P.
    Univ Gothenburg, Tjarmo Marine Lab, Dept Marine Sci, Stromstad, Sweden..
    Dubilier, N.
    Max Planck Inst Marine Mikrobiol, Bremen, Germany..
    Acquisition of a Novel Sulfur-Oxidizing Symbiont in the Gutless Marine Worm Inanidrilus exumae2018Ingår i: Applied and Environmental Microbiology, ISSN 0099-2240, E-ISSN 1098-5336, Vol. 84, nr 7, artikel-id e02267-17Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Gutless phallodrilines are marine annelid worms without a mouth or gut, which live in an obligate association with multiple bacterial endosymbionts that supply them with nutrition. In this study, we discovered an unusual symbiont community in the gutless phallodriline Inanidrilus exumae that differs markedly from the microbiomes of all 22 of the other host species examined. Comparative 16S rRNA gene sequence analysis and fluorescence in situ hybridization revealed that I. exumae harbors cooccurring gamma-, alpha-, and deltaproteobacterial symbionts, while all other known host species harbor gamma-and either alpha-or deltaproteobacterial symbionts. Surprisingly, the primary chemoautotrophic sulfur oxidizer "Candidatus Thiosymbion" that occurs in all other gutless phallodriline hosts does not appear to be present in I. exumae. Instead, I. exumae harbors a bacterial endosymbiont that resembles "Ca. Thiosymbion" morphologically and metabolically but originates from a novel lineage within the class Gammaproteo-bacteria. This endosymbiont, named Gamma 4 symbiont here, had a 16S rRNA gene sequence that differed by at least 7% from those of other free-living and symbiotic bacteria and by 10% from that of "Ca. Thiosymbion." Sulfur globules in the Gamma 4 symbiont cells, as well as the presence of genes characteristic for autotrophy (cbbL) and sulfur oxidation (aprA), indicate that this symbiont is a chemoautotrophic sulfur oxidizer. Our results suggest that a novel lineage of free-living bacteria was able to establish a stable and specific association with I. exumae and appears to have displaced the "Ca. Thiosymbion" symbionts originally associated with these hosts. IMPORTANCE All 22 gutless marine phallodriline species examined to date live in a highly specific association with endosymbiotic, chemoautotrophic sulfur oxidizers called "Ca. Thiosymbion." These symbionts evolved from a single common ancestor and represent the ancestral trait for this host group. They are transmitted vertically and assumed to be in transition to becoming obligate endosymbionts. It is therefore surprising that despite this ancient, evolutionary relationship between phallodriline hosts and "Ca. Thiosymbion," these symbionts are apparently no longer present in Inanidrilus exumae. They appear to have been displaced by a novel lineage of sulfur-oxidizing bacteria only very distantly related to "Ca. Thiosymbion." Thus, this study highlights the remarkable plasticity of both animals and bacteria in establishing beneficial associations: the phallodriline hosts were able to acquire and maintain symbionts from two very different lineages of bacteria, while sulfur-oxidizing bacteria from two very distantly related lineages were able to independently establish symbiotic relationships with phallodriline hosts.

  • 24.
    Berglund, Eva C.
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för organismbiologi, Molekylär evolution.
    Ellegaard, Kirsten
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för organismbiologi, Molekylär evolution.
    Granberg, Fredrik
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för organismbiologi, Molekylär evolution.
    Xie, Zhoupeng
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för organismbiologi, Molekylär evolution.
    Maruyama, Soichi
    Kosoy, Michael Y.
    Birtles, Richard J.
    Andersson, Siv G. E.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för organismbiologi, Molekylär evolution.
    Rapid diversification by recombination in Bartonella grahamii from wild rodents in Asia contrasts with low levels of genomic divergence in Northern Europe and America2010Ingår i: Molecular Ecology, ISSN 0962-1083, E-ISSN 1365-294X, Vol. 19, nr 11, s. 2241-2255Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Bartonella is a genus of vector-borne bacteria that infect the red blood cells of mammals, and includes several human-specific and zoonotic pathogens. Bartonella grahamii has a wide host range and is one of the most prevalent Bartonella species in wild rodents. We studied the population structure, genome content and genome plasticity of a collection of 26 B. grahamii isolates from 11 species of wild rodents in seven countries. We found strong geographic patterns, high recombination frequencies and large variations in genome size in B. grahamii compared with previously analysed cat- and human-associated Bartonella species. The extent of sequence divergence in B. grahamii populations was markedly lower in Europe and North America than in Asia, and several recombination events were predicted between the Asian strains. We discuss environmental and demographic factors that may underlie the observed differences.

  • 25.
    Bergman, Ebba
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för cell- och molekylärbiologi, Molekylär evolution.
    Haplotype Inference as a caseof Maximum Satisfiability: A strategy for identifying multi-individualinversion points in computational phasing2017Självständigt arbete på avancerad nivå (yrkesexamen), 20 poäng / 30 hpStudentuppsats (Examensarbete)
    Abstract [en]

    Phasing genotypes from sequence data is an important step betweendata gathering and downstream analysis in population genetics,disease studies, and multiple other fields. This determination ofthe sequences of markers corresponding to the individualchromosomes can be done on data where the markers are in lowdensity across the chromosome, such as from single nucleotidepolymorphism (SNP) microarrays, or on data with a higher localdensity of markers like in next generation sequencing (NGS). Thesorted markers may then be used for many different analyses anddata processing such as linkage analysis, or inference of missinggenotypes in the process of imputation

    cnF2freq is a haplotype phasing program that uses an uncommonapproach allowing it to divide big groups of related individualsinto smaller ones. It sets an initial haplotype phase and theniteratively changes it using estimations from Hidden MarkovModels. If a marker is judged to have been placed in the wronghaplotype, a switch needs to be made so that it belongs to thecorrect phase. The objective of this project was to go fromallowing only one individual within a group to be switched in aniteration to allowing multiple switches that are dependent on eachother.

    The result of this project is a theoretical solution for allowingmultiple dependent switches in cnF2freq, and an implementedsolution using the max-SAT solver toulbar2.

  • 26.
    Bernander, Rolf
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för organismbiologi, Molekylär evolution.
    Ettema, Thijs J.G.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för organismbiologi, Molekylär evolution.
    FtsZ-less cell division in archaea and bacteria2010Ingår i: Current Opinion in Microbiology, ISSN 1369-5274, E-ISSN 1879-0364, Vol. 13, nr 6, s. 747-752Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    A dedicated cell division machinery is needed for efficient proliferation of an organism. The eukaryotic actin-myosin based mechanism and the bacterial FtsZ-dependent machinery have both been characterized in detail, and a third division mechanism, the Cdv system, was recently discovered in archaea from the Crenarchaeota phylum. Despite these findings, division mechanisms remain to be identified in, for example, organisms belonging to the bacterial PVC superphylum, bacteria with extremely reduced genomes, wall-less archaea and bacteria, and in archaea that carry out the division process without cell constriction. Cytokinesis mechanisms in these clades and individual taxa are likely to include adaptation of host functions to division of bacterial symbionts, transfer of bacterial division genes into the host genome, vesicle formation without a dedicated constriction machinery, cross-wall formation without invagination, as well as entirely novel division mechanisms.

  • 27.
    Bernander, Rolf
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för cell- och molekylärbiologi, Molekylär evolution.
    Lind, Anders E.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för cell- och molekylärbiologi, Molekylär evolution.
    Ettema, Thijs J.G.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för cell- och molekylärbiologi, Molekylär evolution.
    An archaeal origin for the actin cytoskeleton: implications for eukaryogenesis2011Ingår i: Communicative & Integrative Biology, ISSN 1942-0889, E-ISSN 1942-0889, Vol. 4, nr 6, s. 664-667Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    A hallmark of the eukaryotic cell is the actin cytoskeleton, involved in a wide array of processes ranging from shape determination and phagocytosis to intracellular transport and cytokinesis. Recently, we reported the discovery of an actin-based cytoskeleton also in Archaea. The archaeal actin ortholog, Crenactin, was shown to belong to a conserved operon, Arcade (actin-related cytoskeleton in Archaea involved in shape determination), encoding an additional set of cytoskeleton-associated proteins. Here, we elaborate on the implications of these findings for the evolutionary relation between archaea and eukaryotes, with particular focus on the possibility that eukaryotic actin and actin-related proteins have evolved from an ancestral archaeal actin gene. Archaeal actin could thus have played an important role in cellular processes essential for the origin and early evolution of the eukaryotic lineage. Further exploration of uncharacterized archaeal lineages is necessary to find additional missing pieces in the evolutionary trajectory that ultimately gave rise to present-day organisms.

  • 28.
    Bisch, Gaelle
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för cell- och molekylärbiologi, Molekylär evolution. Uppsala universitet, Science for Life Laboratory, SciLifeLab.
    Neuvonen, Minna M.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för cell- och molekylärbiologi, Molekylär evolution. Uppsala universitet, Science for Life Laboratory, SciLifeLab.
    Pierce, Naomi E.
    Harvard Univ, Dept Organism & Evolutionary Biol, Cambridge, MA 02138 USA.
    Russell, Jacob A.
    Drexel Univ, Dept Biol, Philadelphia, PA 19104 USA.
    Koga, Ryuichi
    Natl Inst Adv Ind Sci & Technol, Bioprod Res Inst, Tsukuba, Ibaraki, Japan.
    Sanders, Jon G.
    Harvard Univ, Dept Organism & Evolutionary Biol, Cambridge, MA 02138 USA;Univ Calif San Diego, Dept Pediat, La Jolla, CA 92093 USA.
    Lukasik, Piotr
    Drexel Univ, Dept Biol, Philadelphia, PA 19104 USA;Univ Montana, Div Biol Sci, Missoula, MT 59812 USA.
    Andersson, Siv G. E.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för cell- och molekylärbiologi, Molekylär evolution. Uppsala universitet, Science for Life Laboratory, SciLifeLab.
    Genome Evolution of Bartonellaceae Symbionts of Ants at the Opposite Ends of the Trophic Scale2018Ingår i: Genome Biology and Evolution, ISSN 1759-6653, E-ISSN 1759-6653, Vol. 10, nr 7, s. 1687-1704Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Many insects rely on bacterial symbionts to supply essential amino acids and vitamins that are deficient in their diets, but metabolic comparisons of closely related gut bacteria in insects with different dietary preferences have not been performed. Here, we demonstrate that herbivorous ants of the genus Dolichoderus from the Peruvian Amazon host bacteria of the family Bartonellaceae, known for establishing chronic or pathogenic infections in mammals. We detected these bacteria in all studied Dolichoderus species, and found that they reside in the midgut wall, that is, the same location as many previously described nutritional endosymbionts of insects. The genomic analysis of four divergent strains infecting different Dolichoderus species revealed genes encoding pathways for nitrogen recycling and biosynthesis of several vitamins and all essential amino acids. In contrast, several biosynthetic pathways have been lost, whereas genes for the import and conversion of histidine and arginine to glutamine have been retained in the genome of a closely related gut bacterium of the carnivorous ant Harpegnathos saltator. The broad biosynthetic repertoire in Bartonellaceae of herbivorous ants resembled that of gut bacteria of honeybees that likewise feed on carbohydrate-rich diets. Taken together, the broad distribution of Bartonellaceae across Dolichoderus ants, their small genome sizes, the specific location within hosts, and the broad biosynthetic capability suggest that these bacteria are nutritional symbionts in herbivorous ants. The results highlight the important role of the host nutritional biology for the genomic evolution of the gut microbiota-and conversely, the importance of the microbiota for the nutrition of hosts.

  • 29.
    Björkholm, Patrik
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för cell- och molekylärbiologi, Molekylär evolution.
    Ernst, Andreas M.
    Yale Univ, Sch Med, Dept Cell Biol, New Haven, CT 06510 USA..
    Hagström, Erik
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för cell- och molekylärbiologi, Molekylär evolution.
    Andersson, Siv G. E.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för cell- och molekylärbiologi, Molekylär evolution.
    Why mitochondria need a genome revisited2017Ingår i: FEBS Letters, ISSN 0014-5793, E-ISSN 1873-3468, Vol. 591, nr 1, s. 65-75Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    In this paper, we experimentally address the debate about why functional transfer of mitochondrial genes to the nucleus has been halted in some organismal groups and why cytosolic expression of mitochondrial proteins has proven remarkably difficult. By expressing all 13 human mitochondrial-encoded genes with strong mitochondrial-targeting sequences in the cytosol of human cells, we show that all proteins, except ATP8, are transported to the endoplasmic reticulum (ER). These results confirm and extend previous findings based on three mitochondrial genes lacking mitochondrial-targeting sequences that also were relocated to the ER during cytosolic expression. We conclude that subcellular protein targeting constitutes a major barrier to functional transfer of mitochondrial genes to the nuclear genome.

  • 30.
    Björkholm, Patrik
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för cell- och molekylärbiologi, Molekylär evolution.
    Harish, Ajith
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för cell- och molekylärbiologi, Molekylär evolution.
    Hagström, Erik
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för cell- och molekylärbiologi, Molekylär evolution.
    Ernst, Andreas M.
    Andersson, Siv G. E.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för cell- och molekylärbiologi, Molekylär evolution.
    Mitochondrial genomes are retained by selective constraints on protein targeting2015Ingår i: Proceedings of the National Academy of Sciences of the United States of America, ISSN 0027-8424, E-ISSN 1091-6490, Vol. 112, nr 33, s. 10154-10161Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Mitochondria are energy-producing organelles in eukaryotic cells considered to be of bacterial origin. The mitochondrial genome has evolved under selection for minimization of gene content, yet it is not known why not all mitochondrial genes have been transferred to the nuclear genome. Here, we predict that hydrophobic membrane proteins encoded by the mitochondrial genomes would be recognized by the signal recognition particle and targeted to the endoplasmic reticulum if they were nuclear-encoded and translated in the cytoplasm. Expression of the mitochondrially encoded proteins Cytochrome oxidase subunit 1, Apocytochrome b, and ATP synthase subunit 6 in the cytoplasm of HeLa cells confirms export to the endoplasmic reticulum. To examine the extent to which the mitochondrial proteome is driven by selective constraints within the eukaryotic cell, we investigated the occurrence of mitochondrial protein domains in bacteria and eukaryotes. The accessory protein domains of the oxidative phosphorylation system are unique to mitochondria, indicating the evolution of new protein folds. Most of the identified domains in the accessory proteins of the ribosome are also found in eukaryotic proteins of other functions and locations. Overall, one-third of the protein domains identified in mitochondrial proteins are only rarely found in bacteria. We conclude that the mitochondrial genome has been maintained to ensure the correct localization of highly hydrophobic membrane proteins. Taken together, the results suggest that selective constraints on the eukaryotic cell have played a major role in modulating the evolution of the mitochondrial genome and proteome.

  • 31.
    Björklund, Åsa K.
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för cell- och molekylärbiologi, Molekylär evolution. Ludwig Inst Canc Res, S-10401 Stockholm, Sweden.;Karolinska Inst, Dept Cell & Mol Biol, Stockholm, Sweden..
    Forkel, Marianne
    Karolinska Inst, Dept Med Huddinge, Ctr Infect Med, Stockholm, Sweden..
    Picelli, Simone
    Ludwig Inst Canc Res, S-10401 Stockholm, Sweden..
    Konya, Viktoria
    Karolinska Inst, Dept Med Huddinge, Ctr Infect Med, Stockholm, Sweden..
    Theorell, Jakob
    Karolinska Inst, Dept Med Huddinge, Ctr Infect Med, Stockholm, Sweden..
    Friberg, Danielle
    Karolinska Univ Hosp, Dept Otorhinolaryngol, Stockholm, Sweden.;Karolinska Inst, CLINTEC, Stockholm, Sweden..
    Sandberg, Rickard
    Ludwig Inst Canc Res, S-10401 Stockholm, Sweden.;Karolinska Inst, Dept Cell & Mol Biol, Stockholm, Sweden..
    Mjosberg, Jenny
    Karolinska Inst, Dept Med Huddinge, Ctr Infect Med, Stockholm, Sweden..
    The heterogeneity of human CD127(+) innate lymphoid cells revealed by single-cell RNA sequencing2016Ingår i: Nature Immunology, ISSN 1529-2908, E-ISSN 1529-2916, Vol. 17, nr 4, s. 451-460Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Innate lymphoid cells (ILCs) are increasingly appreciated as important participants in homeostasis and inflammation. Substantial plasticity and heterogeneity among ILC populations have been reported. Here we have delineated the heterogeneity of human ILCs through single-cell RNA sequencing of several hundreds of individual tonsil CD127(+) ILCs and natural killer (NK) cells. Unbiased transcriptional clustering revealed four distinct populations, corresponding to ILC1 cells, ILC2 cells, ILC3 cells and NK cells, with their respective transcriptomes recapitulating known as well as unknown transcriptional profiles. The single-cell resolution additionally divulged three transcriptionally and functionally diverse subpopulations of ILC3 cells. Our systematic comparison of single-cell transcriptional variation within and between ILC populations provides new insight into ILC biology during homeostasis, with additional implications for dysregulation of the immune system.

  • 32. Blombach, Fabian
    et al.
    Launay, Helene
    Snijders, Ambrosius P. L.
    Zorraquino, Violeta
    Wu, Hao
    de Koning, Bart
    Brouns, Stan J. J.
    Ettema, Thijs J. G.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för cell- och molekylärbiologi, Molekylär evolution. Uppsala universitet, Science for Life Laboratory, SciLifeLab.
    Camilloni, Carlo
    Cavalli, Andrea
    Vendruscolo, Michele
    Dickman, Mark J.
    Cabrita, Lisa D.
    LA Teana, Anna
    Benelli, Dario
    Londei, Paola
    Christodoulou, John
    van der Oost, John
    Archaeal MBF1 binds to 30S and 70S ribosomes via its helix-turn-helix domain2014Ingår i: Biochemical Journal, ISSN 0264-6021, E-ISSN 1470-8728, Vol. 462, s. 373-384Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    MBF1 (multi-protein bridging factor 1) is a protein containing a conserved HTH (helix-turn-helix) domain in both eukaryotes and archaea. Eukaryotic MBF1 has been reported to function as a transcriptional co-activator that physically bridges transcription regulators with the core transcription initiation machinery of RNA polymerase II. In addition, MBF1 has been found to be associated with polyadenylated mRNA in yeast as well as in mammalian cells. aMBF1 (archaeal MBF1) is very well conserved among most archaeal lineages; however, its function has so far remained elusive. To address this, we have conducted a molecular characterization of this aMBF1. Affinity purification of interacting proteins indicates that aMBF1 binds to ribosomal subunits. On sucrose density gradients, aMBF1 co-fractionates with free 30S ribosomal subunits as well as with 70S ribosomes engaged in translation. Binding of aMBF1 to ribosomes does not inhibit translation. Using NMR spectroscopy, we show that aMBF1 contains a long intrinsically disordered linker connecting the predicted N-terminal zinc-ribbon domain with the C-terminal HTH domain. The HTH domain, which is conserved in all archaeal and eukaryotic MBF1 homologues, is directly involved in the association of aMBF1 with ribosomes. The disordered linker of the ribosome-bound aMBF1 provides the N-terminal domain with high flexibility in the aMBF1 ribosome complex. Overall, our findings suggest a role for aMBF1 in the archaeal translation process.

  • 33.
    Brindefalk, Björn
    et al.
    Uppsala universitet, Science for Life Laboratory, SciLifeLab.
    Ettema, Thijs J. G.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för cell- och molekylärbiologi, Molekylär evolution. Uppsala universitet, Science for Life Laboratory, SciLifeLab.
    Viklund, Johan
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för cell- och molekylärbiologi, Molekylär evolution. Uppsala universitet, Science for Life Laboratory, SciLifeLab.
    Thollesson, Mikael
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för organismbiologi. Uppsala universitet, Science for Life Laboratory, SciLifeLab.
    Andersson, Siv G. E.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för cell- och molekylärbiologi, Molekylär evolution. Uppsala universitet, Science for Life Laboratory, SciLifeLab.
    A Phylometagenomic Exploration of Oceanic Alphaproteobacteria Reveals Mitochondrial Relatives Unrelated to the SAR11 Clade2011Ingår i: PLoS ONE, ISSN 1932-6203, E-ISSN 1932-6203, Vol. 6, nr 9, s. e24457-Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Background: According to the endosymbiont hypothesis, the mitochondrial system for aerobic respiration was derived from an ancestral Alphaproteobacterium. Phylogenetic studies indicate that the mitochondrial ancestor is most closely related to the Rickettsiales. Recently, it was suggested that Candidatus Pelagibacter ubique, a member of the SAR11 clade that is highly abundant in the oceans, is a sister taxon to the mitochondrial-Rickettsiales clade. The availability of ocean metagenome data substantially increases the sampling of Alphaproteobacteria inhabiting the oxygen-containing waters of the oceans that likely resemble the originating environment of mitochondria.

    Methodology/Principal Findings: We present a phylogenetic study of the origin of mitochondria that incorporates metagenome data from the Global Ocean Sampling (GOS) expedition. We identify mitochondrially related sequences in the GOS dataset that represent a rare group of Alphaproteobacteria, designated OMAC (Oceanic Mitochondria Affiliated Clade) as the closest free-living relatives to mitochondria in the oceans. In addition, our analyses reject the hypothesis that the mitochondrial system for aerobic respiration is affiliated with that of the SAR11 clade.

    Conclusions/Significance: Our results allude to the existence of an alphaproteobacterial clade in the oxygen-rich surface waters of the oceans that represents the closest free-living relative to mitochondria identified thus far. In addition, our findings underscore the importance of expanding the taxonomic diversity in phylogenetic analyses beyond that represented by cultivated bacteria to study the origin of mitochondria.

  • 34.
    Burri, Reto
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och genetik, Evolutionsbiologi.
    Nater, Alexander
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och genetik, Evolutionsbiologi.
    Kawakami, Takeshi
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och genetik, Evolutionsbiologi.
    Mugal, Carina F.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och genetik, Evolutionsbiologi.
    Ólason, Páll I.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för cell- och molekylärbiologi, Molekylär evolution.
    Smeds, Linnea
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och genetik, Evolutionsbiologi.
    Suh, Alexander
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och genetik, Evolutionsbiologi.
    Dutoit, Ludovic
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och genetik, Evolutionsbiologi.
    Bures, Stanislav
    Palacky Univ, Dept Zool, Lab Ornithol, Olomouc 77146, Czech Republic..
    Garamszegi, Laszlo Z.
    CSIC, Dept Evolutionary Ecol, Estn Biol Donana, Seville 41092, Spain..
    Hogner, Silje
    Univ Oslo, Ctr Ecol & Evolutionary Synth, Dept Biosci, N-0316 Oslo, Norway.;Univ Oslo, Nat Hist Museum, N-0318 Oslo, Norway..
    Moreno, Juan
    CSIC, Museo Nacl Ciencias Nat, E-28006 Madrid, Spain..
    Qvarnström, Anna
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och genetik, Zooekologi.
    Ruzic, Milan
    Bird Protect & Study Soc Serbia, Novi Sad 21000, Serbia..
    Saether, Stein-Are
    Univ Oslo, Ctr Ecol & Evolutionary Synth, Dept Biosci, N-0316 Oslo, Norway.;Norwegian Inst Nat Res NINA, N-7034 Trondheim, Norway..
    Saetre, Glenn-Peter
    Univ Oslo, Ctr Ecol & Evolutionary Synth, Dept Biosci, N-0316 Oslo, Norway..
    Toeroek, Janos
    Eotvos Lorand Univ, Dept Systemat Zool & Ecol, Behav Ecol Grp, H-1117 Budapest, Hungary..
    Ellegren, Hans
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och genetik, Evolutionsbiologi.
    Linked selection and recombination rate variation drive the evolution of the genomic landscape of differentiation across the speciation continuum of Ficedula flycatchers2015Ingår i: Genome Research, ISSN 1088-9051, E-ISSN 1549-5469, Vol. 25, nr 11, s. 1656-1665Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Speciation is a continuous process during which genetic changes gradually accumulate in the genomes of diverging species. Recent studies have documented highly heterogeneous differentiation landscapes, with distinct regions of elevated differentiation ("differentiation islands") widespread across genomes. However, it remains unclear which processes drive the evolution of differentiation islands; how the differentiation landscape evolves as speciation advances; and ultimately, how differentiation islands are related to speciation. Here, we addressed these questions based on population genetic analyses of 200 resequenced genomes from 10 populations of four Ficedula flycatcher sister species. We show that a heterogeneous differentiation landscape starts emerging among populations within species, and differentiation islands evolve recurrently in the very same genomic regions among independent lineages. Contrary to expectations from models that interpret differentiation islands as genomic regions involved in reproductive isolation that are shielded from gene flow, patterns of sequence divergence (d(XY) relative node depth) do not support a major role of gene flow in the evolution of the differentiation landscape in these species. Instead, as predicted by models of linked selection, genome-wide variation in diversity and differentiation can be explained by variation in recombination rate and the density of targets for selection. We thus conclude that the heterogeneous landscape of differentiation in Ficedula flycatchers evolves mainly as the result of background selection and selective sweeps in genomic regions of low recombination. Our results emphasize the necessity of incorporating linked selection as a null model to identify genome regions involved in adaptation and speciation.

  • 35.
    Bysani, Madhusudhan
    et al.
    Lund Univ, Scania Univ Hosp, Diabet Ctr, Dept Clin Sci,Epigenet & Diabet Unit, Malmo, Sweden.
    Agren, Rasmus
    Chalmers Univ Technol, Sci Life Lab, Natl Bioinformat Infrastruct Sweden, Dept Biol & Biol Engn, Gothenburg, Sweden.
    Davegardh, Cajsa
    Lund Univ, Scania Univ Hosp, Diabet Ctr, Dept Clin Sci,Epigenet & Diabet Unit, Malmo, Sweden.
    Volkov, Petr
    Lund Univ, Scania Univ Hosp, Diabet Ctr, Dept Clin Sci,Epigenet & Diabet Unit, Malmo, Sweden.
    Ronn, Tina
    Lund Univ, Scania Univ Hosp, Diabet Ctr, Dept Clin Sci,Epigenet & Diabet Unit, Malmo, Sweden.
    Unneberg, Per
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för cell- och molekylärbiologi, Molekylär evolution. Uppsala universitet, Science for Life Laboratory, SciLifeLab.
    Bacos, Karl
    Lund Univ, Scania Univ Hosp, Diabet Ctr, Dept Clin Sci,Epigenet & Diabet Unit, Malmo, Sweden.
    Ling, Charlotte
    Lund Univ, Scania Univ Hosp, Diabet Ctr, Dept Clin Sci,Epigenet & Diabet Unit, Malmo, Sweden.
    ATAC-seq reveals alterations in open chromatin in pancreatic islets from subjects with type 2 diabetes2019Ingår i: Scientific Reports, ISSN 2045-2322, E-ISSN 2045-2322, Vol. 9, artikel-id 7785Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Impaired insulin secretion from pancreatic islets is a hallmark of type 2 diabetes (T2D). Altered chromatin structure may contribute to the disease. We therefore studied the impact of T2D on open chromatin in human pancreatic islets. We used assay for transposase-accessible chromatin using sequencing (ATAC-seq) to profile open chromatin in islets from T2D and non-diabetic donors. We identified 57,105 and 53,284 ATAC-seq peaks representing open chromatin regions in islets of nondiabetic and diabetic donors, respectively. The majority of ATAC-seq peaks mapped near transcription start sites. Additionally, peaks were enriched in enhancer regions and in regions where islet-specific transcription factors (TFs), e.g. FOXA2, MAFB, NKX2.2, NKX6.1 and PDX1, bind. Islet ATAC-seq peaks overlap with 13 SNPs associated with T2D (e.g. rs7903146, rs2237897, rs757209, rs11708067 and rs878521 near TCF7L2, KCNQ1, HNF1B, ADCY5 and GCK, respectively) and with additional 67 SNPs in LD with known T2D SNPs (e.g. SNPs annotated to GIPR, KCNJ11, GLIS3, IGF2BP2, FTO and PPARG). There was enrichment of open chromatin regions near highly expressed genes in human islets. Moreover, 1,078 open chromatin peaks, annotated to 898 genes, differed in prevalence between diabetic and non-diabetic islet donors. Some of these peaks are annotated to candidate genes for T2D and islet dysfunction (e.g. HHEX, HMGA2, GLIS3, MTNR1B and PARK2) and some overlap with SNPs associated with T2D (e.g. rs3821943 near WFS1 and rs508419 near ANK1). Enhancer regions and motifs specific to key TFs including BACH2, FOXO1, FOXA2, NEUROD1, MAFA and PDX1 were enriched in differential islet ATAC-seq peaks of T2D versus non-diabetic donors. Our study provides new understanding into how T2D alters the chromatin landscape, and thereby accessibility for TFs and gene expression, in human pancreatic islets.

  • 36.
    Bäckström, Disa
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för cell- och molekylärbiologi, Molekylär evolution.
    Exploring the diversity and evolution of giant viruses in deep sea sediments using genome-resolved metagenomics2018Licentiatavhandling, sammanläggning (Övrigt vetenskapligt)
    Abstract [en]

    Viruses are the most abundant biological entities on this planet, which is impressive considering that they are completely dependent on their hosts for reproduction. Recently the idea of what viruses are has changed dramatically, with the discovery of giant viruses that belong to the Nucleocytoplasmic Large DNA Viruses (NCLDV), such as Mimiviridae, Marseilleviridae, and the proposed families Pandoraviruses, and Pithoviruses. Not only are some of these viruses as large as bacteria in size, their genomes also exceed the size of some prokaryotic genomes. The evolutionary path to viral giganticism is not yet fully understood, and several opposing theories have been proposed. The more examples of giant viruses we have to study, the clearer the picture becomes. The rate of discovery, however, is limited by the low capacity of culturing. In an effort to contribute through culture-independent methods, I used genome-resolved metagenomics to retrieve genomes of 23 new members of the NCLDV from deep sea sediment samples that were taken near Loki’s Castle hydrothermal vent field. This method has previously been used to study uncultured Bacteria and Archaea, but few successful cases of metagenomic binning of NCLDV have been documented. New methods for refinement and quality control of the binned genomes were developed, combining reads profiling with differential coverage binning, and composition-based cleaning of potentially contaminating sequences. The binned genomes represent several novel clades of NCLDV, the most noteworthy ones distantly related to Pithoviruses and Marseilleviridae, and greatly expand their overall diversity. Phylogenetic analysis of their genome content supports the independent evolution of viral giganticism from smaller viruses. Continued use of metagenomics to explore the presence of NCLDV in environmental samples will lead to new insights into their diversity, evolution, and biology.

    Delarbeten
    1. Novel virus genomes from deep sea sediments expand the ocean megavirome and support independent origins of viral gigantism
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    (Engelska)Ingår i: Artikel i tidskrift (Refereegranskat) Submitted
    Nationell ämneskategori
    Evolutionsbiologi
    Identifikatorer
    urn:nbn:se:uu:diva-362611 (URN)
    Tillgänglig från: 2018-10-11 Skapad: 2018-10-11 Senast uppdaterad: 2018-10-14Bibliografiskt granskad
  • 37.
    Bäckström, Disa
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för cell- och molekylärbiologi, Molekylär evolution. Uppsala universitet, Science for Life Laboratory, SciLifeLab.
    Yutin, Natalya
    Natl Lib Med, Natl Ctr Biotechnol Informat, NIH, Bethesda, MD, USA.
    Jorgensen, Steffen L.
    Univ Bergen, Ctr Geobiol, Dept Biol, Bergen, Norway.
    Dharamshi, Jennah
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för cell- och molekylärbiologi, Molekylär evolution. Uppsala universitet, Science for Life Laboratory, SciLifeLab.
    Homa, Felix
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för cell- och molekylärbiologi, Molekylär evolution. Uppsala universitet, Science for Life Laboratory, SciLifeLab.
    Zaremba-Niedzwiedzka, Katarzyna
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för cell- och molekylärbiologi, Molekylär evolution. Uppsala universitet, Science for Life Laboratory, SciLifeLab.
    Spang, Anja
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för cell- och molekylärbiologi, Molekylär evolution. Uppsala universitet, Science for Life Laboratory, SciLifeLab. Royal Netherlands Inst Sea Res, NIOZ, Dept Marine Microbiol & Biogeochem, Yerseke, Netherlands; Univ Utrecht, Den Burg, Netherlands.
    Wolf, Yuri I.
    Natl Lib Med, Natl Ctr Biotechnol Informat, NIH, Bethesda, MD, USA.
    Koonin, Eugene V.
    Natl Lib Med, Natl Ctr Biotechnol Informat, NIH, Bethesda, MD, USA.
    Ettema, Thijs J. G.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för cell- och molekylärbiologi, Molekylär evolution. Uppsala universitet, Science for Life Laboratory, SciLifeLab.
    Virus Genomes from Deep Sea Sediments Expand the Ocean Megavirome and Support Independent Origins of Viral Gigantism2019Ingår i: mBio, ISSN 2161-2129, E-ISSN 2150-7511, Vol. 10, nr 2, artikel-id e02497-18Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The nucleocytoplasmic large DNA viruses (NCLDV) of eukaryotes (proposed order, “Megavirales”) include the families Poxviridae, Asfarviridae, Iridoviridae, Ascoviridae, Phycodnaviridae, Marseilleviridae, and Mimiviridae, as well as still unclassified pithoviruses, pandoraviruses, molliviruses, and faustoviruses. Several of these virus groups include giant viruses, with genome and particle sizes exceeding those of many bacterial and archaeal cells. We explored the diversity of the NCLDV in deep sea sediments from the Loki’s Castle hydrothermal vent area. Using metagenomics, we reconstructed 23 high-quality genomic bins of novel NCLDV, 15 of which are related to pithoviruses, 5 to marseilleviruses, 1 to iridoviruses, and 2 to klosneuviruses. Some of the identified pithovirus-like and marseillevirus-like genomes belong to deep branches in the phylogenetic tree of core NCLDV genes, substantially expanding the diversity and phylogenetic depth of the respective groups. The discovered viruses, including putative giant members of the family Marseilleviridae, have a broad range of apparent genome sizes, in agreement with the multiple, independent origins of gigantism in different branches of the NCLDV. Phylogenomic analysis reaffirms the monophyly of the pithovirus-iridovirus-marseillevirus branch of the NCLDV. Similarly to other giant viruses, the pithovirus-like viruses from Loki’s Castle encode translation systems components. Phylogenetic analysis of these genes indicates a greater bacterial contribution than had been detected previously. Genome comparison suggests extensive gene exchange between members of the pithovirus-like viruses and Mimiviridae. Further exploration of the genomic diversity of Megavirales in additional sediment samples is expected to yield new insights into the evolution of giant viruses and the composition of the ocean megavirome.

    Importance: Genomics and evolution of giant viruses are two of the most vigorously developing areas of virus research. Lately, metagenomics has become the main source of new virus genomes. Here we describe a metagenomic analysis of the genomes of large and giant viruses from deep sea sediments. The assembled new virus genomes substantially expand the known diversity of the nucleocytoplasmic large DNA viruses of eukaryotes. The results support the concept of independent evolution of giant viruses from smaller ancestors in different virus branches.

  • 38.
    Bäckström, Disa
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för cell- och molekylärbiologi, Molekylär evolution. Uppsala universitet, Science for Life Laboratory, SciLifeLab.
    Yutin, Natalya
    National Center for Biotechnology Information, National Library of Medicine. National Institutes of Health, Bethesda, MD 20894, USA.
    Jørgensen, Steffen L.
    Department of Biology, Centre for Geobiology, University of Bergen, N -5020 Bergen, Norway.
    Dharamshi, Jennah
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för cell- och molekylärbiologi, Molekylär evolution. Uppsala universitet, Science for Life Laboratory, SciLifeLab.
    Homa, Felix
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för cell- och molekylärbiologi, Molekylär evolution. Uppsala universitet, Science for Life Laboratory, SciLifeLab.
    Zaremba-Niedzwiedzka, Katarzyna
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för cell- och molekylärbiologi, Molekylär evolution. Uppsala universitet, Science for Life Laboratory, SciLifeLab.
    Spang, Anja
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för cell- och molekylärbiologi, Molekylär evolution. Uppsala universitet, Science for Life Laboratory, SciLifeLab.
    Wolf, Yuri I.
    National Center for Biotechnology Information, National Library of Medicine. National Institutes of Health, Bethesda, MD 20894, USA.
    Koonin, Eugene V.
    National Center for Biotechnology Information, National Library of Medicine. National Institutes of Health, Bethesda, MD 20894, USA.
    Ettema, Thijs J. G.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för cell- och molekylärbiologi, Molekylär evolution. Uppsala universitet, Science for Life Laboratory, SciLifeLab.
    Novel virus genomes from deep sea sediments expand the ocean megavirome and support independent origins of viral gigantismIngår i: Artikel i tidskrift (Refereegranskat)
  • 39. Caffrey, Brian E.
    et al.
    Williams, Tom A.
    Jiang, Xiaowei
    Toft, Christina
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för cell- och molekylärbiologi, Molekylär evolution.
    Hokamp, Karsten
    Fares, Mario A.
    Proteome-Wide Analysis of Functional Divergence in Bacteria: Exploring a Host of Ecological Adaptations2012Ingår i: PLoS ONE, ISSN 1932-6203, E-ISSN 1932-6203, Vol. 7, nr 4, s. e35659-Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Functional divergence is the process by which new genes and functions originate through the modification of existing ones. Both genetic and environmental factors influence the evolution of new functions, including gene duplication or changes in the ecological requirements of an organism. Novel functions emerge at the expense of ancestral ones and are generally accompanied by changes in the selective forces at constrained protein regions. We present software capable of analyzing whole proteomes, identifying putative amino acid replacements leading to functional change in each protein and performing statistical tests on all tabulated data. We apply this method to 750 complete bacterial proteomes to identify high-level patterns of functional divergence and link these patterns to ecological adaptations. Proteome-wide analyses of functional divergence in bacteria with different ecologies reveal a separation between proteins involved in information processing (Ribosome biogenesis etc.) and those which are dependent on the environment (energy metabolism, defense etc.). We show that the evolution of pathogenic and symbiotic bacteria is constrained by their association with the host, and also identify unusual events of functional divergence even in well-studied bacteria such as Escherichia coli. We present a description of the roles of phylogeny and ecology in functional divergence at the level of entire proteomes in bacteria.

  • 40.
    Cenci, Ugo
    et al.
    Dalhousie Univ, Dept Biochem & Mol Biol, Halifax, NS B3H 4R2, Canada;Dalhousie Univ, Ctr Comparat Genom & Evolutionary Bioinformat, Halifax, NS, Canada.