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  • 151.
    Ahlén, I
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Faculty of Science and Technology, Biology, Department of Evolutionary Biology.
    Ölands fladdermusfauna.1997In: Länsstyrelsen i Kalmar län meddelar, Vol. 7, p. 1-26Report (Other scientific)
  • 152.
    Ahlén, I
    et al.
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Faculty of Science and Technology, Biology, Department of Evolutionary Biology.
    Baagöe, HJ
    Use of ultrasound detectors for bat studies in Europe - experiences from field identifications, surveys and monitoring.1999In: Acta Chiropterol, Vol. 1, p. 137-150Article in journal (Other scientific)
  • 153.
    Ahlén, I
    et al.
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Faculty of Science and Technology, Biology, Department of Evolutionary Biology.
    Cederroth, C
    Varfågel Lanius excubitor av rasen homeyeri gästade Öland 1998.1999In: Calidris, Vol. 28, p. 24-26Article in journal (Other scientific)
  • 154.
    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 University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Plant Ecology and Evolution.
    Unneberg, Per
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Cell and Molecular Biology, Molecular 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 University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics. 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 DNA2018In: Quaternary Science Reviews, ISSN 0277-3791, E-ISSN 1873-457X, Vol. 181, p. 19-29Article in journal (Refereed)
    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.

  • 155.
    Ahmed Osman, Omneya
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Limnology. Uppsala University, Science for Life Laboratory, SciLifeLab.
    Beier, Sara
    Leibniz Inst Balt Sea Res, Warnemunde, Germany..
    Grabherr, Manfred
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Biochemistry and Microbiology. Uppsala University, Science for Life Laboratory, SciLifeLab.
    Bertilsson, Stefan
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Limnology. Uppsala University, Science for Life Laboratory, SciLifeLab.
    Interactions of Freshwater Cyanobacteria with Bacterial Antagonists2017In: Applied and Environmental Microbiology, ISSN 0099-2240, E-ISSN 1098-5336, Vol. 83, no 7, article id UNSP e02634Article in journal (Refereed)
    Abstract [en]

    Cyanobacterial and algal mass development, or blooms, have severe effects on freshwater and marine systems around the world. Many of these phototrophs produce a variety of potent toxins, contribute to oxygen depletion, and affect water quality in several ways. Coexisting antagonists, such as cyanolytic bacteria, hold the potential to suppress, or even terminate, such blooms, yet the nature of this interaction is not well studied. We isolated 31 cyanolytic bacteria affiliated with the genera Pseudomonas, Stenotrophomonas, Acinetobacter, and Delftia from three eutrophic freshwater lakes in Sweden and selected four phylogenetically diverse bacterial strains with strong-to-moderate lytic activity. To characterize their functional responses to the presence of cyanobacteria, we performed RNA sequencing (RNA-Seq) experiments on coculture incubations, with an initial predator-prey ratio of 1: 1. Genes involved in central cellular pathways, stress-related heat or cold shock proteins, and antitoxin genes were highly expressed in both heterotrophs and cyanobacteria. Heterotrophs in coculture expressed genes involved in cell motility, signal transduction, and putative lytic activity. L, D-Transpeptidase was the only significantly upregulated lytic gene in Stenotrophomonas rhizophila EK20. Heterotrophs also shifted their central metabolism from the tricarboxylic acid cycle to the glyoxylate shunt. Concurrently, cyanobacteria clearly show contrasting antagonistic interactions with the four tested heterotrophic strains, which is also reflected in the physical attachment to their cells. In conclusion, antagonistic interactions with cyanobacteria were initiated within 24 h, and expression profiles suggest varied responses for the different cyanobacteria and studied cyanolytes. IMPORTANCE Here, we present how gene expression profiles can be used to reveal interactions between bloom-forming freshwater cyanobacteria and antagonistic heterotrophic bacteria. Species-specific responses in both heterotrophs and cyanobacteria were identified. The study contributes to a better understanding of the interspecies cellular interactions underpinning the persistence and collapse of cyanobacterial blooms.

  • 156.
    AHNESJO, I
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Evolutionary Biology.
    TEMPERATURE AFFECTS MALE AND FEMALE POTENTIAL REPRODUCTIVE RATES DIFFERENTLY IN THE SEX-ROLE REVERSED PIPEFISH, SYNGNATHUS-TYPHLE1995In: BEHAVIORAL ECOLOGY, ISSN 1045-2249, Vol. 6, no 2, p. 229-233Article in journal (Other academic)
    Abstract [en]

    The differences in potential reproductive rate between the sexes can be used to predict the operational sex ratio and the patterns and intensity of mating competition and hence sexual selection in a population. This article describes how one environmental

  • 157.
    Ahnesjo, Ingrid
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Evolutionary Biology.
    Apparent resource competition among embryos in the brood pouch of a male pipefish1996In: BEHAVIORAL ECOLOGY AND SOCIOBIOLOGY, ISSN 0340-5443, Vol. 38, no 3, p. 167-172Article in journal (Other academic)
    Abstract [en]

    Embryo success was studied in the paternally brooding pipefish Syngnathus typhle. During brooding, which lasts about a month, males provide embryos in their brood pouch with nutrients and oxygen via a placenta-like structure. Egg size depends on female si

  • 158.
    Ahnesjo, Ingrid
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Animal ecology.
    Craig, J. F.
    The biology of Syngnathidae: pipefishes, seadragons and seahorses2011In: Journal of Fish Biology, ISSN 0022-1112, E-ISSN 1095-8649, Vol. 78, no 6, p. 1597-1602Article in journal (Other academic)
  • 159.
    Ahnesjo, Ingrid
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Evolutionary Biology.
    Kvarnemo, C
    Merilaita, S
    Using potential reproductive rates to predict mating competition among individuals qualified to mate2001In: BEHAVIORAL ECOLOGY, ISSN 1045-2249, Vol. 12, no 4, p. 397-401Article in journal (Refereed)
    Abstract [en]

    The potential reproductive rate (PRR), which is the offspring production per unit time each sex would achieve if unconstrained by mate availability, often differs between the sexes. An increasing sexual difference in PRR predicts an intensified mating com

  • 160.
    Ahnesjö, Ingrid
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Evolution, Animal Ecology.
    Behavioural temperature preference in a brooding male pipefish Syngnathus typhle2008In: Journal of Fish Biology, ISSN 0022-1112, E-ISSN 1095-8649, Vol. 73, no 4, p. 1039-1045Article in journal (Refereed)
    Abstract [en]

    In the broad-nosed pipefish Syngnathus typhle, brooding males positioned themselves significantly more often towards the warmer part (18 degrees C) of an aquarium. whereas females were indifferent in this respect. This behavioural temperature preference may increase male brooding rate and indirectly influence patterns of mating competition. (c) 2008 The Author Journal compilation (c) 2008 The Fisheries Society of the British Isles.

  • 161.
    Ahnesjö, Ingrid
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Animal ecology.
    Bokrecension av Retorik för naturvetare: skrivande som fördjupar lärandet2014In: Högre Utbildning, ISSN 2000-7558, E-ISSN 2000-7558, Vol. 4, no 1, p. 83-85Article, book review (Other academic)
  • 162.
    Ahnesjö, Ingrid
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics.
    Consequences Of Male Brood Care: Weight And Number Of Newborn In A Sex-Role Reversed Pipefish1992In: Functional Ecology, ISSN 0269-8463, E-ISSN 1365-2435, Vol. 6, no 3, p. 274-281Article in journal (Refereed)
    Abstract [en]

    1. In the pipefish Syngnathus typhle sex roles are reversed, as females compete for access to males. In this species males provide all brood care (i.e. are 'pregnant') and female reproductive rate exceeds the reproductive rate of males. Consequently females are limited by access to mates and male reproductive success is limited by male brooding ability and/or mate quality. Thus, phenomena like brood reduction and a trade-off between number and weight of newborn may be expected in males. 2. In this paper I demonstrate the following in males of S. typhle: (a) the initial weight of the egg (received from the female) positively influenced the weight of newborn; (b) in the male's brood pouch, number of newborn frequently is less than number of eggs initially received (brood reduction), and the extent of this decrease in brood size positively influenced the weight of newborn; (c) a trade-off between number and weight of newborn was demonstrated in males from field samples and in large experimental males (independent of brood reduction), but not in small males that presumably allocated resources to several other demands (condition, growth, etc.); (d) paternal length, per se, did not affect the weight of newborn. 3. The results indicate that in S. typhle, male reproductive success is limited by their own brooding ability and influenced by the egg size received (indirectly quality of mate), which may be expected in a situation of sex-role reversal.

  • 163.
    Ahnesjö, Ingrid
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Animal ecology.
    Equal Opportunity for Sexual Evolution2011In: BioScience, ISSN 0006-3568, E-ISSN 1525-3244, Vol. 61, no 8, p. 641-642Article, book review (Other academic)
  • 164.
    Ahnesjö, Ingrid
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics.
    Fewer Newborn Result In Superior Juveniles In The Paternally Brooding Pipefish Syngnathus-Typhle L1992In: Journal of Fish Biology, ISSN 0022-1112, E-ISSN 1095-8649, Vol. 41, no Suppl. B, p. 53-63Article in journal (Refereed)
  • 165.
    Ahnesjö, Ingrid
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Animal ecology.
    Mate Choice in Males and Females2010In: Encyclopedia of Animal Behavior / [ed] Michael D. Breed and Janice Moore, Oxford: Academic Press, 2010, p. 394-398Chapter in book (Other academic)
    Abstract [en]

    Finding a ‘dream mate’ is important for fitness in many sexually reproducing animals because half the genome of the offspring will come from this mate. Individuals that choose their mates carefully may gain both direct benefits (i.e., good care, territories, and other resources) and indirect benefits (genes that improve offspring viability or attractiveness). Mate choices occur in both sexes and the same individuals can be both choosy and competitive. Mate choice and mating competition often result in sexual selection and the evolution of secondary sexual characters. Mate choice is interactive, context dependent, operates on multiple traits, and varies in time and space.

  • 166.
    Ahnesjö, Ingrid
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Evolution. Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Animal ecology.
    Seahorses and Their Relatives2010In: Journal of Fish Biology, ISSN 0022-1112, E-ISSN 1095-8649, Vol. 77, no 1, p. 308-309Article, book review (Other academic)
  • 167.
    Ahnesjö, Ingrid
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Animal ecology.
    Berglund, Anders
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Animal ecology.
    Forsgren, Elisabet
    Norsk institutt for naturforskning i Trondheim, Norway.
    Karlsson, Anna
    Enheten för biologisk mångfald och områdesskydd, Havs och Vattenmyndigheten, Göteborg.
    Kvarnemo, Charlotta
    Zoologi, Göteborgs universitet, Göteborg.
    Magnhagen, Carin
    Fiskbiologi, Sveriges lantbruksuniversitet (SLU), Umeå.
    Rosenqvist, Gunilla
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, Natural Resources and Sustainable Development. Etologi, NTNU, Trondheim, Norway.
    Östlund Nilsson, Sara
    Nasjonalbiblioteket, Oslo, Norway.
    En beteende-ekologisk forskningsperiod på Klubbans biologiska station: Rapport från återträff med Doktorer som disputerade (1983-2001) på avhandlingar med fältarbete på Klubbans Biologiska station. I en värld av kantnålar, stubbar, spiggar och nudingar.2018Report (Other (popular science, discussion, etc.))
    Abstract [en]

    We had the fortune as PhD-students and scientists in Animal Ecology at Uppsala University, to spend joyful and creative field work summers at Klubban Biological Station, during the 1980-90’s. A reunion in June 2018 resulted in this report highlighting research on pipefishes, gobies, sticklebacks and nudibranchs. Our research on these animals have provided novel insights and knowledge of the process of sexual selection and paternal care. These animals have, in many aspects, now become model organisms in evolutionary behavioral ecology in marine environments. Our list of publications provides many examples of how environmental factors influence how sexual selection and mate choice operate, how predictors like potential reproductive rates, operational sex ratios work and how male parental care is prominent in influencing selection. This research, that started at Klubban, has broadened our understanding of the ecological importance of shallow marine areas. The evolutionary understanding of how males and females can behave and how adaptive traits are selected in interaction with social and an increasingly changing ambient environment is in focus in our continued scientific endeavors. We have happily compiled this report illustrating how science and scientist can stimulate each other at a wonderful place like Klubban Biological Station, with the access to amazing organisms like pipefishes, gobies, sticklebacks and nudibranchs.

  • 168.
    Ahnesjö, Ingrid
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Animal ecology.
    Braga Goncalves, Ines
    Mate Choice in Males and Females2017In: Reference Module in Life Sciences, Elsevier, 2017, p. 394-398Chapter in book (Other academic)
    Abstract [en]

    To find a “dream mate” is important for fitness in all sexually reproducing animals because half of the genome of one’s offspring comes from the chosen mate. Individuals that choose their mates may gain both direct benefits (ie, care or other resources) and indirect benefits (genes improving offspring viability or attractiveness). Mate choice occurs in males and females, and individuals may simultaneously be choosy and compete to be chosen. Processes that often result in sexual selection and in the evolution of secondary sexual characters. Mate choice is context-dependent, operates on multiple traits and varies in time and space.

  • 169.
    Ahnesjö, Ingrid
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Animal ecology.
    Braga Goncalves, Ines
    Mate choice in males and females2019In: Encyclopedia of Animal Behavior / [ed] Choe J.C., Elsevier, 2019, 2, p. 432-440Chapter in book (Refereed)
    Abstract [en]

    To find a “dream mate” is important for fitness in all sexually reproducing animals because half of the genome of one’soffspring comes from the chosen mate. Individuals that choose their mates may gain both direct benefits (i.e., care or other resources) and indirect benefits (genes that improve offspring viability or attractiveness). Mate choice occurs in males and females, and individuals may both be choosy and compete to be chosen. Both processes often result in sexual selection and in the evolution of secondary sexual characters. Mate choice is context-dependent, operates on multiple traits and varies in time and space.

  • 170.
    Ahnesjö, Ingrid
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Animal ecology.
    Forsgren, Elisabet
    Kvarnemo, Charlotta
    Variation in sexual selection in fishes2008In: Fish Behaviour / [ed] Carin Magnhagen, Victoria A. Braithwaite, Elisabet Forsgren, B.G. Kapoor, Enfield: Science Publishers Inc., 2008, p. 303-335Chapter in book (Refereed)
  • 171.
    Ahnesjö, Ingrid
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Animal ecology.
    Vasconcelos, Paula
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Animal ecology.
    Recension: Cordelia Fine. Testosteron Rex: Myten om våra könade hjärnor2018In: Tidskrift för Genusvetenskap, ISSN 1654-5443, E-ISSN 2001-1377, Vol. 39, no 4, p. 123-124Article, book review (Other (popular science, discussion, etc.))
  • 172.
    Ahnesjö, Ingrid
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics.
    Vincent, Amanda
    Alatalo, Rauno
    Halliday, Tim
    Sutherland, William J
    The role of females in influencing mating patterns1993In: Behavioral Ecology, ISSN 1045-2249, E-ISSN 1465-7279, Vol. 4, no 2, p. 187-189Article in journal (Refereed)
  • 173. Aho, T
    et al.
    Rönn, J
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Faculty of Science and Technology, Biology, Department of Ecology and Evolution. Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Faculty of Science and Technology, Biology, Department of Ecology and Evolution, Animal Ecology.
    Piironen, J
    Björklund, M
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Faculty of Science and Technology, Biology, Department of Ecology and Evolution. Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Faculty of Science and Technology, Biology, Department of Ecology and Evolution, Animal Ecology. Zooekologi.
    Impacts of effective population size on genetic diversity and relatedness in hatchery reared Brown trout (Salmo trutta L.)2006In: Aquaculture, Vol. 253, p. 244-248Article in journal (Refereed)
  • 174. Aikio, S
    et al.
    Pakkasmaa, S
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Faculty of Science and Technology, Biology, Department of Evolutionary Biology. Department of Ecology and Evolution, Population Biology. populationsbiologi.
    Relatedness and competitive assymetry - implications for growth and population dynamics2003In: Oikos, Vol. 100, p. 283-290Article in journal (Refereed)
  • 175.
    Ajawatanawong, Pravech
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Organismal Biology, Systematic Biology.
    Mine the Gaps: Evolution of Eukaryotic Protein Indels and their Application for Testing Deep Phylogeny2014Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Insertions/deletions (indels) are potentially powerful evolutionary markers, but little is known about their evolution and few tools exist to effectively study them. To address this, I developed SeqFIRE, a tool for automated identification and extraction of indels from protein multiple sequence alignments. The program also extracts conserved alignment blocks, thus covering all major steps in preparing multiple sequence alignments for phylogenetic analysis.

    I then used SeqFIRE to build an indel database, using 299 single copy proteins from a broad taxonomic sampling of mainly multicellular eukaryotes. A total of 4,707 indels were extracted, of which 901 are simple (one genetic event) and 3,806 are complex (multiple events). The most abundant indels are single amino acid simple indels. Indel frequency decreases exponentially with length and shows a linear relationship with host protein size. Singleton indels reveal a strong bias towards insertions (2.31 x deletions on average). These analyses also identify 43 indels marking major clades in Plantae and Fungi (clade defining indels or CDIs), but none for Metazoa.

    In order to study the 3806 complex indels they were first classified by number of states. Analysis of the 2-state complex and simple indels combined (“bi-state indels”) confirms that insertions are over 2.5 times as frequent as deletions. Three-quarters of the complex indels had three-nine states (“slightly complex indels”). A tree-assisted search method was developed allowing me to identify 1,010 potential CDIs supporting all examined major branches of Plantae and Fungi.

    Forty-two proteins were also found to host complex indel CDIs for the deepest branches of Metazoa. After expanding the taxon set for these proteins, I identified a total of 49 non-bilaterian specific CDIs. Parsimony analysis of these indels places Ctenophora as sister taxon to all other Metazoa including Porifera. Six CDIs were also found placing Placozoa as sister to Bilateria. I conclude that slightly complex indels are a rich source of CDIs, and my tree-assisted search strategy could be automated and implemented in the program SeqFIRE to facilitate their discovery. This will have important implications for mining the phylogenomic content of the vast resource of protist genome data soon to become available.

    List of papers
    1. SeqFIRE: a web application for automated extraction of indel regions and conserved blocks from protein multiple sequence alignments
    Open this publication in new window or tab >>SeqFIRE: a web application for automated extraction of indel regions and conserved blocks from protein multiple sequence alignments
    Show others...
    2012 (English)In: Nucleic Acids Research, ISSN 0305-1048, E-ISSN 1362-4962, Vol. 40, no W1, p. W340-W347Article in journal (Refereed) Published
    Abstract [en]

    Analyses of multiple sequence alignments generally focus on well-defined conserved sequence blocks, while the rest of the alignment is largely ignored or discarded. This is especially true in phylogenomics, where large multigene datasets are produced through automated pipelines. However, some of the most powerful phylogenetic markers have been found in the variable length regions of multiple alignments, particularly insertions/deletions (indels) in protein sequences. We have developed Sequence Feature and Indel Region Extractor (SeqFIRE) to enable the automated identification and extraction of indels from protein sequence alignments. The program can also extract conserved blocks and identify fast evolving sites using a combination of conservation and entropy. All major variables can be adjusted by the user, allowing them to identify the sets of variables most suited to a particular analysis or dataset. Thus, all major tasks in preparing an alignment for further analysis are combined in a single flexible and user-friendly program. The output includes a numbered list of indels, alignments in NEXUS format with indels annotated or removed and indel-only matrices. SeqFIRE is a user-friendly web application, freely available online at www.seqfire.org/.

    Keywords
    Indels, Alignment, Conserved blocks
    National Category
    Bioinformatics (Computational Biology) Bioinformatics and Systems Biology
    Identifiers
    urn:nbn:se:uu:diva-179937 (URN)10.1093/nar/gks561 (DOI)000306670900056 ()
    Available from: 2012-08-27 Created: 2012-08-27 Last updated: 2019-08-28Bibliographically approved
    2. Evolution of protein indels in plants, animals and fungi
    Open this publication in new window or tab >>Evolution of protein indels in plants, animals and fungi
    2013 (English)In: BMC Evolutionary Biology, ISSN 1471-2148, E-ISSN 1471-2148, Vol. 13, p. 140-Article in journal (Refereed) Published
    Abstract [en]

    Background: Insertions/deletions (indels) in protein sequences are useful as drug targets, protein structure predictors, species diagnostics and evolutionary markers. However there is limited understanding of indel evolutionary patterns. We sought to characterize indel patterns focusing first on the major groups of multicellular eukaryotes. Results: Comparisons of complete proteomes from a taxonically broad set of primarily Metazoa, Fungi and Viridiplantae yielded 299 substantial (>250aa) universal, single-copy (in-paralog only) proteins, from which 901 simple (present/absent) and 3,806 complex (multistate) indels were extracted. Simple indels are mostly small (1-7aa) with a most frequent size class of 1aa. However, even these simple looking indels show a surprisingly high level of hidden homoplasy (multiple independent origins). Among the apparently homoplasy-free simple indels, we identify 69 potential clade-defining indels (CDIs) that may warrant closer examination. CDIs show a very uneven taxonomic distribution among Viridiplante (13 CDIs), Fungi (40 CDIs), and Metazoa (0 CDIs). An examination of singleton indels shows an excess of insertions over deletions in nearly all examined taxa. This excess averages 2.31 overall, with a maximum observed value of 7.5 fold. Conclusions: We find considerable potential for identifying taxon-marker indels using an automated pipeline. However, it appears that simple indels in universal proteins are too rare and homoplasy-rich to be used for pure indel-based phylogeny. The excess of insertions over deletions seen in nearly every genome and major group examined maybe useful in defining more realistic gap penalties for sequence alignment. This bias also suggests that insertions in highly conserved proteins experience less purifying selection than do deletions.

    Keywords
    Indels, Rare genomic changes, Phylogeny, Insertion/deletion, Multiple sequence alignment, Eukaryote evolution, Indel profiles
    National Category
    Natural Sciences
    Identifiers
    urn:nbn:se:uu:diva-204971 (URN)10.1186/1471-2148-13-140 (DOI)000321461800001 ()
    Available from: 2013-08-16 Created: 2013-08-13 Last updated: 2019-08-28Bibliographically approved
    3. An automatable method for high throughput analysis of evolutionary patterns in slightly complex indels and its application to the deep phylogeny of Metazoa
    Open this publication in new window or tab >>An automatable method for high throughput analysis of evolutionary patterns in slightly complex indels and its application to the deep phylogeny of Metazoa
    2014 (English)Article in journal (Refereed) Submitted
    Abstract [en]

    Insertions/deletions (indels) in protein sequences are potential powerful evolutionary markers. However, these characters have rarely been explored systematically at deep phylogenetic levels. Previous analyses of simple (2-state) clade defining indels (CDIs) in universal eukaryotic proteins found none to support any major animal clade. We hypothesized that CDIs might still be found in the remaining population of indels, which we term complex indels. Here, we propose a method for analyzing the simplest class of complex indels the “slightly complex indels”, and use these to investigate deep branches in animal phylogeny. Complex indels with two states, called bi-state indels, show similar evolutionary patterns to singleton simple indels and confirms that insertion mutations are more common than deletions. Exploration of CDIs in 2- to 9-state complex indels shows strong support for all examined branches of fungi and Archaeplastida. Surprisingly, we also found CDIs supporting major branches in animals, particular in vertebrates. We then expanded the search to non-bilaterial animals (Porifera, Cnidaria and Ctenophora). The phylogenetic tree reconstructed by CDIs places the Ctenophore Mnemiopsis leidyi as the deepest branch of animals with 6 CDIs support. Trichoplax adhaerens is closely related to the Bilateria. Moreover, the indel phylogeny shows Nematostella vectensis and Hydra magnipapillata are paraphyletic group and position of Cnidarian branches seems to be problematic in the indel phylogeny because of homoplasy. This might be solved if we discover CDIs from animal specific proteins, which emerged after the universal orthologous proteins.Evolutionary Patterns in Slightly Complex Protein Insertions/Deletions (Indels) and Their Application to the Study of Deep Phylogeny in Metazoa

    National Category
    Other Biological Topics
    Identifiers
    urn:nbn:se:uu:diva-216842 (URN)
    Available from: 2014-01-27 Created: 2014-01-27 Last updated: 2019-08-28Bibliographically approved
  • 176.
    Ajawatanawong, Pravech
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Organismal Biology, Systematic Biology.
    Atkinson, Gemma C.
    Watson-Haigh, Nathan S.
    MacKenzie, Bryony
    Baldauf, Sandra L.
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Organismal Biology, Systematic Biology.
    SeqFIRE: a web application for automated extraction of indel regions and conserved blocks from protein multiple sequence alignments2012In: Nucleic Acids Research, ISSN 0305-1048, E-ISSN 1362-4962, Vol. 40, no W1, p. W340-W347Article in journal (Refereed)
    Abstract [en]

    Analyses of multiple sequence alignments generally focus on well-defined conserved sequence blocks, while the rest of the alignment is largely ignored or discarded. This is especially true in phylogenomics, where large multigene datasets are produced through automated pipelines. However, some of the most powerful phylogenetic markers have been found in the variable length regions of multiple alignments, particularly insertions/deletions (indels) in protein sequences. We have developed Sequence Feature and Indel Region Extractor (SeqFIRE) to enable the automated identification and extraction of indels from protein sequence alignments. The program can also extract conserved blocks and identify fast evolving sites using a combination of conservation and entropy. All major variables can be adjusted by the user, allowing them to identify the sets of variables most suited to a particular analysis or dataset. Thus, all major tasks in preparing an alignment for further analysis are combined in a single flexible and user-friendly program. The output includes a numbered list of indels, alignments in NEXUS format with indels annotated or removed and indel-only matrices. SeqFIRE is a user-friendly web application, freely available online at www.seqfire.org/.

  • 177.
    Ajawatanawong, Pravech
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Organismal Biology, Systematic Biology.
    Baldauf, Sandra
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Organismal Biology, Systematic Biology.
    An automatable method for high throughput analysis of evolutionary patterns in slightly complex indels and its application to the deep phylogeny of Metazoa2014Article in journal (Refereed)
    Abstract [en]

    Insertions/deletions (indels) in protein sequences are potential powerful evolutionary markers. However, these characters have rarely been explored systematically at deep phylogenetic levels. Previous analyses of simple (2-state) clade defining indels (CDIs) in universal eukaryotic proteins found none to support any major animal clade. We hypothesized that CDIs might still be found in the remaining population of indels, which we term complex indels. Here, we propose a method for analyzing the simplest class of complex indels the “slightly complex indels”, and use these to investigate deep branches in animal phylogeny. Complex indels with two states, called bi-state indels, show similar evolutionary patterns to singleton simple indels and confirms that insertion mutations are more common than deletions. Exploration of CDIs in 2- to 9-state complex indels shows strong support for all examined branches of fungi and Archaeplastida. Surprisingly, we also found CDIs supporting major branches in animals, particular in vertebrates. We then expanded the search to non-bilaterial animals (Porifera, Cnidaria and Ctenophora). The phylogenetic tree reconstructed by CDIs places the Ctenophore Mnemiopsis leidyi as the deepest branch of animals with 6 CDIs support. Trichoplax adhaerens is closely related to the Bilateria. Moreover, the indel phylogeny shows Nematostella vectensis and Hydra magnipapillata are paraphyletic group and position of Cnidarian branches seems to be problematic in the indel phylogeny because of homoplasy. This might be solved if we discover CDIs from animal specific proteins, which emerged after the universal orthologous proteins.Evolutionary Patterns in Slightly Complex Protein Insertions/Deletions (Indels) and Their Application to the Study of Deep Phylogeny in Metazoa

  • 178.
    Ajawatanawong, Pravech
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Organismal Biology, Systematic Biology.
    Baldauf, Sandra L.
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Organismal Biology, Systematic Biology.
    Evolution of protein indels in plants, animals and fungi2013In: BMC Evolutionary Biology, ISSN 1471-2148, E-ISSN 1471-2148, Vol. 13, p. 140-Article in journal (Refereed)
    Abstract [en]

    Background: Insertions/deletions (indels) in protein sequences are useful as drug targets, protein structure predictors, species diagnostics and evolutionary markers. However there is limited understanding of indel evolutionary patterns. We sought to characterize indel patterns focusing first on the major groups of multicellular eukaryotes. Results: Comparisons of complete proteomes from a taxonically broad set of primarily Metazoa, Fungi and Viridiplantae yielded 299 substantial (>250aa) universal, single-copy (in-paralog only) proteins, from which 901 simple (present/absent) and 3,806 complex (multistate) indels were extracted. Simple indels are mostly small (1-7aa) with a most frequent size class of 1aa. However, even these simple looking indels show a surprisingly high level of hidden homoplasy (multiple independent origins). Among the apparently homoplasy-free simple indels, we identify 69 potential clade-defining indels (CDIs) that may warrant closer examination. CDIs show a very uneven taxonomic distribution among Viridiplante (13 CDIs), Fungi (40 CDIs), and Metazoa (0 CDIs). An examination of singleton indels shows an excess of insertions over deletions in nearly all examined taxa. This excess averages 2.31 overall, with a maximum observed value of 7.5 fold. Conclusions: We find considerable potential for identifying taxon-marker indels using an automated pipeline. However, it appears that simple indels in universal proteins are too rare and homoplasy-rich to be used for pure indel-based phylogeny. The excess of insertions over deletions seen in nearly every genome and major group examined maybe useful in defining more realistic gap penalties for sequence alignment. This bias also suggests that insertions in highly conserved proteins experience less purifying selection than do deletions.

  • 179.
    Aken, Bronwen L.
    et al.
    European Bioinformat Inst Wellcome Genome Campus, European Mol Biol Lab, Cambridge CB10 1SD, England.;Wellcome Trust Sanger Inst Wellcome Genome Campus, Cambridge CB10 1SA, England..
    Ayling, Sarah
    Wellcome Trust Sanger Inst Wellcome Genome Campus, Cambridge CB10 1SA, England.;Genome Anal Ctr, Norwich Res Pk, Norwich NR4 7UH, Norfolk, England..
    Barrell, Daniel
    European Bioinformat Inst Wellcome Genome Campus, European Mol Biol Lab, Cambridge CB10 1SD, England.;Wellcome Trust Sanger Inst Wellcome Genome Campus, Cambridge CB10 1SA, England.;Eagle Genom Ltd, Babraham Res Campus, Cambridge CB22 3AT, England..
    Clarke, Laura
    Wellcome Trust Sanger Inst Wellcome Genome Campus, Cambridge CB10 1SA, England.;European Bioinformat Inst, European Mol Biol Lab, Wellcome Genome Campus, Cambridge CB10 1SD, England..
    Curwen, Valery
    Wellcome Trust Sanger Inst Wellcome Genome Campus, Cambridge CB10 1SA, England..
    Fairley, Susan
    Wellcome Trust Sanger Inst Wellcome Genome Campus, Cambridge CB10 1SA, England.;European Bioinformat Inst, European Mol Biol Lab, Wellcome Genome Campus, Cambridge CB10 1SD, England..
    Banet, Julio Fernandez
    Wellcome Trust Sanger Inst Wellcome Genome Campus, Cambridge CB10 1SA, England.;Pfizer Inc, 10646 Sci Ctr Dr, San Diego, CA 92121 USA..
    Billis, Konstantinos
    European Bioinformat Inst Wellcome Genome Campus, European Mol Biol Lab, Cambridge CB10 1SD, England.;Wellcome Trust Sanger Inst Wellcome Genome Campus, Cambridge CB10 1SA, England..
    Giron, Carlos Garcia
    European Bioinformat Inst Wellcome Genome Campus, European Mol Biol Lab, Cambridge CB10 1SD, England.;Wellcome Trust Sanger Inst Wellcome Genome Campus, Cambridge CB10 1SA, England..
    Hourlier, Thibaut
    European Bioinformat Inst Wellcome Genome Campus, European Mol Biol Lab, Cambridge CB10 1SD, England.;Wellcome Trust Sanger Inst Wellcome Genome Campus, Cambridge CB10 1SA, England..
    Howe, Kevin
    Wellcome Trust Sanger Inst Wellcome Genome Campus, Cambridge CB10 1SA, England.;European Bioinformat Inst, European Mol Biol Lab, Wellcome Genome Campus, Cambridge CB10 1SD, England..
    Kähäri, Andreas
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Cell and Molecular Biology, Computational Biology and Bioinformatics. Wellcome Trust Sanger Inst Wellcome Genome Campus, Cambridge CB10 1SA, England.
    Kokocinski, Felix
    Wellcome Trust Sanger Inst Wellcome Genome Campus, Cambridge CB10 1SA, England..
    Martin, Fergal J.
    European Bioinformat Inst Wellcome Genome Campus, European Mol Biol Lab, Cambridge CB10 1SD, England.;Wellcome Trust Sanger Inst Wellcome Genome Campus, Cambridge CB10 1SA, England..
    Murphy, Daniel N.
    European Bioinformat Inst Wellcome Genome Campus, European Mol Biol Lab, Cambridge CB10 1SD, England.;Wellcome Trust Sanger Inst Wellcome Genome Campus, Cambridge CB10 1SA, England..
    Nag, Rishi
    European Bioinformat Inst Wellcome Genome Campus, European Mol Biol Lab, Cambridge CB10 1SD, England.;Wellcome Trust Sanger Inst Wellcome Genome Campus, Cambridge CB10 1SA, England..
    Ruffier, Magali
    Wellcome Trust Sanger Inst Wellcome Genome Campus, Cambridge CB10 1SA, England.;European Bioinformat Inst, European Mol Biol Lab, Wellcome Genome Campus, Cambridge CB10 1SD, England..
    Schuster, Michael
    European Bioinformat Inst Wellcome Genome Campus, European Mol Biol Lab, Cambridge CB10 1SD, England.;Austrian Acad Sci, CeMM Res Ctr Mol Med, A-1090 Vienna, Austria..
    Tang, Y. Amy
    Wellcome Trust Sanger Inst Wellcome Genome Campus, Cambridge CB10 1SA, England.;European Bioinformat Inst, European Mol Biol Lab, Wellcome Genome Campus, Cambridge CB10 1SD, England..
    Vogel, Jan-Hinnerk
    Wellcome Trust Sanger Inst Wellcome Genome Campus, Cambridge CB10 1SA, England.;Genentech Inc, 1 DNAWay, San Francisco, CA 94080 USA..
    White, Simon
    Wellcome Trust Sanger Inst Wellcome Genome Campus, Cambridge CB10 1SA, England.;Baylor Coll Med, Human Genome Sequencing Ctr, Houston, TX 77030 USA..
    Zadissa, Amonida
    Wellcome Trust Sanger Inst Wellcome Genome Campus, Cambridge CB10 1SA, England.;European Bioinformat Inst, European Mol Biol Lab, Wellcome Genome Campus, Cambridge CB10 1SD, England..
    Flicek, Paul
    European Bioinformat Inst Wellcome Genome Campus, European Mol Biol Lab, Cambridge CB10 1SD, England.;Wellcome Trust Sanger Inst Wellcome Genome Campus, Cambridge CB10 1SA, England..
    Searle, Stephen M. J.
    Wellcome Trust Sanger Inst Wellcome Genome Campus, Cambridge CB10 1SA, England..
    The Ensembl gene annotation system2016In: Database: The Journal of Biological Databases and Curation, ISSN 1758-0463, E-ISSN 1758-0463, article id baw093Article in journal (Refereed)
    Abstract [en]

    The Ensembl gene annotation system has been used to annotate over 70 different vertebrate species across a wide range of genome projects. Furthermore, it generates the automatic alignment-based annotation for the human and mouse GENCODE gene sets. The system is based on the alignment of biological sequences, including cDNAs, proteins and RNA-seq reads, to the target genome in order to construct candidate transcript models. Careful assessment and filtering of these candidate transcripts ultimately leads to the final gene set, which is made available on the Ensembl website. Here, we describe the annotation process in detail.

  • 180.
    Akhverdyan, M
    et al.
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Faculty of Science and Technology, Biology, Department of Evolutionary Biology.
    Fredga, K
    EM studies of female meiosis in wood lemmings with different sex chromosome constitutions2001In: JOURNAL OF EXPERIMENTAL ZOOLOGY, ISSN 0022-104X, Vol. 290, no 5, p. 504-516Article in journal (Refereed)
    Abstract [en]

    The chromosomes were studied throughout meiotic prophase by electron microscopy of surface-spread oocytes from one XX, four X*X, and three X*Y female wood lemmings, Myopus schisticolor. The X* chromosome had originated from X by a deletion and an inversio

  • 181.
    Akiyama, Reiko
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Plant Ecology and Evolution.
    Life History and Tolerance and Resistance against Herbivores in Natural Populations of Arabidopsis thaliana2011Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    In this thesis, I combined observational studies with field and greenhouse experiments to examine selection on life history traits and variation in tolerance and resistance against herbivores in natural populations of the annual herb Arabidopsis thaliana in its native range. I investigated (1) phenotypic selection on flowering time and plant size, (2) the effects of timing of germination on plant fitness, (3) the effect of leaf damage on seed production, and (4) correlations between resistance against a specialist and a generalist insect herbivore.

    In all three study populations, flowering time was negatively related to plant fitness, but in only one of the populations, significant selection on flowering time was detected when controlling for size prior to the flowering season. The results show that correlations between flowering time and plant fecundity may be confounded by variation in plant size prior to the reproductive season.

    A field experiment detected conflicting selection on germination time: Early germination was associated with low seedling survival, but also with large leaf rosette before winter and high survival and fecundity among established plants. The results suggest that low survival among early germinating seeds is the main force opposing the evolution of earlier germination, and that the optimal timing of germination should vary in space and time as a function of the relative strength of selection acting during different life-history stages.

    Experimental leaf damage demonstrated that tolerance to damage was lowest among vegetative plants early in the season, and highest among flowering plants later in the season. Given similar damage levels, leaf herbivores feeding on plants before flowering should thus exert stronger selection on defence traits than those feeding on plants during flowering.

    Resistance against larval feeding by the specialist Plutella xylostella was negatively correlated with resistance against larval feeding by the generalist Mamestra brassicae and with resistance against oviposition by P. xylostella when variation in resistance was examined within and among two Swedish and two Italian A. thaliana populations. The results suggest that negative correlations between resistance against different herbivores and different life-history stages of herbivores may contribute to the maintenance of genetic variation in resistance.

    List of papers
    1. Selection on flowering time in three natural populations of Arabidopsis thaliana
    Open this publication in new window or tab >>Selection on flowering time in three natural populations of Arabidopsis thaliana
    (English)Manuscript (preprint) (Other academic)
    National Category
    Ecology Evolutionary Biology Botany
    Research subject
    Biology with specialization in Ecological Botany
    Identifiers
    urn:nbn:se:uu:diva-159506 (URN)
    Funder
    Swedish Research Council
    Available from: 2011-10-06 Created: 2011-10-03 Last updated: 2011-11-10
    2. Conflicting selection on the timing of germination in a natural population of Arabidopsis thaliana
    Open this publication in new window or tab >>Conflicting selection on the timing of germination in a natural population of Arabidopsis thaliana
    2014 (English)In: Journal of Evolutionary Biology, ISSN 1010-061X, E-ISSN 1420-9101, Vol. 27, no 1, p. 193-199Article in journal (Refereed) Published
    Abstract [en]

    The timing of germination is a key life-history trait that may strongly influence plant fitness and that sets the stage for selection on traits expressed later in the life cycle. In seasonal environments, the period favourable for germination and the total length of the growing season are limited. The optimal timing of germination may therefore be governed by conflicting selection through survival and fecundity. We conducted a field experiment to examine the effects of timing of germination on survival, fecundity and overall fitness in a natural population of the annual herb Arabidopsis thaliana in north-central Sweden. Seedlings were transplanted at three different times in late summer and in autumn covering the period of seed germination in the study population. Early germination was associated with low seedling survival, but also with high survival and fecundity among established plants. The advantages of germinating early more than balanced the disadvantage and selection favoured early germination. The results suggest that low survival among early germinating seeds is the main force opposing the evolution of earlier germination and that the optimal timing of germination should vary in space and time as a function of the direction and strength of selection acting during different life-history stages.

    National Category
    Ecology Evolutionary Biology Botany
    Research subject
    Biology with specialization in Ecological Botany
    Identifiers
    urn:nbn:se:uu:diva-159664 (URN)10.1111/jeb.12293 (DOI)000329254500018 ()
    Funder
    Swedish Research Council
    Available from: 2011-10-06 Created: 2011-10-06 Last updated: 2017-12-08Bibliographically approved
    3. Magnitude and timing of leaf damage affect seed production in a natural population of Arabidopsis thaliana (Brassicaceae)
    Open this publication in new window or tab >>Magnitude and timing of leaf damage affect seed production in a natural population of Arabidopsis thaliana (Brassicaceae)
    2012 (English)In: PLoS ONE, ISSN 1932-6203, E-ISSN 1932-6203, Vol. 7, no 1, p. e30015-Article in journal (Refereed) Published
    Abstract [en]

    Background: The effect of herbivory on plant fitness varies widely. Understanding the causes of this variation is of considerable interest because of its implications for plant population dynamics and trait evolution. We experimentally defoliated the annual herb Arabidopsis thaliana in a natural population in Sweden to test the hypotheses that (a) plant fitness decreases with increasing damage, (b) tolerance to defoliation is lower before flowering than during flowering, and (c) defoliation before flowering reduces number of seeds more strongly than defoliation during flowering, but the opposite is true for effects on seed size.

    Methodology/Principal Findings: In a first experiment, between 0 and 75% of the leaf area was removed in May from plants that flowered or were about to start flowering. In a second experiment, 0, 25%, or 50% of the leaf area was removed from plants on one of two occasions, in mid April when plants were either in the vegetative rosette or bolting stage, or in mid May when plants were flowering. In the first experiment, seed production was negatively related to leaf area removed, and at the highest damage level, also mean seed size was reduced. In the second experiment, removal of 50% of the leaf area reduced seed production by 60% among plants defoliated early in the season at the vegetative rosettes, and by 22% among plants defoliated early in the season at the bolting stage, but did not reduce seed output of plants defoliated one month later. No seasonal shift in the effect of defoliation on seed size was detected.

    Conclusions/Significance: The results show that leaf damage may reduce the fitness of A. thaliana, and suggest that in this population leaf herbivores feeding on plants before flowering should exert stronger selection on defence traits than those feeding on plants during flowering, given similar damage levels.

    National Category
    Ecology Evolutionary Biology Botany
    Research subject
    Biology with specialization in Ecological Botany
    Identifiers
    urn:nbn:se:uu:diva-159665 (URN)10.1371/journal.pone.0030015 (DOI)000301457200028 ()
    Funder
    Swedish Research Council
    Available from: 2011-10-06 Created: 2011-10-06 Last updated: 2017-12-08Bibliographically approved
    4. Genetic variation in leaf morphology and resistance against specialist and generalist insect herbivores in natural populations of Arabidopsis thaliana
    Open this publication in new window or tab >>Genetic variation in leaf morphology and resistance against specialist and generalist insect herbivores in natural populations of Arabidopsis thaliana
    (English)Manuscript (preprint) (Other academic)
    National Category
    Ecology Evolutionary Biology Botany
    Research subject
    Biology with specialization in Ecological Botany
    Identifiers
    urn:nbn:se:uu:diva-159685 (URN)
    Funder
    Swedish Research Council
    Available from: 2011-10-06 Created: 2011-10-06 Last updated: 2011-11-10
  • 182.
    Akiyama, Reiko
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Plant Ecology and Evolution.
    Noack, Sibylle
    Department of Zoology, Stockholm University.
    Ågren, Jon
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Plant Ecology and Evolution.
    Genetic variation in leaf morphology and resistance against specialist and generalist insect herbivores in natural populations of Arabidopsis thalianaManuscript (preprint) (Other academic)
  • 183.
    Akiyama, Reiko
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Plant Ecology and Evolution.
    Ågren, Jon
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Plant Ecology and Evolution.
    Conflicting selection on the timing of germination in a natural population of Arabidopsis thaliana2014In: Journal of Evolutionary Biology, ISSN 1010-061X, E-ISSN 1420-9101, Vol. 27, no 1, p. 193-199Article in journal (Refereed)
    Abstract [en]

    The timing of germination is a key life-history trait that may strongly influence plant fitness and that sets the stage for selection on traits expressed later in the life cycle. In seasonal environments, the period favourable for germination and the total length of the growing season are limited. The optimal timing of germination may therefore be governed by conflicting selection through survival and fecundity. We conducted a field experiment to examine the effects of timing of germination on survival, fecundity and overall fitness in a natural population of the annual herb Arabidopsis thaliana in north-central Sweden. Seedlings were transplanted at three different times in late summer and in autumn covering the period of seed germination in the study population. Early germination was associated with low seedling survival, but also with high survival and fecundity among established plants. The advantages of germinating early more than balanced the disadvantage and selection favoured early germination. The results suggest that low survival among early germinating seeds is the main force opposing the evolution of earlier germination and that the optimal timing of germination should vary in space and time as a function of the direction and strength of selection acting during different life-history stages.

  • 184.
    Akiyama, Reiko
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Plant Ecology and Evolution.
    Ågren, Jon
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Plant Ecology and Evolution.
    Magnitude and timing of leaf damage affect seed production in a natural population of Arabidopsis thaliana (Brassicaceae)2012In: PLoS ONE, ISSN 1932-6203, E-ISSN 1932-6203, Vol. 7, no 1, p. e30015-Article in journal (Refereed)
    Abstract [en]

    Background: The effect of herbivory on plant fitness varies widely. Understanding the causes of this variation is of considerable interest because of its implications for plant population dynamics and trait evolution. We experimentally defoliated the annual herb Arabidopsis thaliana in a natural population in Sweden to test the hypotheses that (a) plant fitness decreases with increasing damage, (b) tolerance to defoliation is lower before flowering than during flowering, and (c) defoliation before flowering reduces number of seeds more strongly than defoliation during flowering, but the opposite is true for effects on seed size.

    Methodology/Principal Findings: In a first experiment, between 0 and 75% of the leaf area was removed in May from plants that flowered or were about to start flowering. In a second experiment, 0, 25%, or 50% of the leaf area was removed from plants on one of two occasions, in mid April when plants were either in the vegetative rosette or bolting stage, or in mid May when plants were flowering. In the first experiment, seed production was negatively related to leaf area removed, and at the highest damage level, also mean seed size was reduced. In the second experiment, removal of 50% of the leaf area reduced seed production by 60% among plants defoliated early in the season at the vegetative rosettes, and by 22% among plants defoliated early in the season at the bolting stage, but did not reduce seed output of plants defoliated one month later. No seasonal shift in the effect of defoliation on seed size was detected.

    Conclusions/Significance: The results show that leaf damage may reduce the fitness of A. thaliana, and suggest that in this population leaf herbivores feeding on plants before flowering should exert stronger selection on defence traits than those feeding on plants during flowering, given similar damage levels.

  • 185.
    Akiyama, Reiko
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Plant Ecology and Evolution.
    Ågren, Jon
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Plant Ecology and Evolution.
    Selection on flowering time in three natural populations of Arabidopsis thalianaManuscript (preprint) (Other academic)
  • 186. Akkoc, Nurullah
    et al.
    Sari, Ismail
    Akar, Servet
    Binicier, Omer
    Thomas, Mark G.
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Evolution, Genomics and Systematics.
    Weale, Michael E.
    Birlik, Merih
    Savran, Yusuf
    Onen, Fatos
    Bradman, Neil
    Plaster, Christopher A.
    Increased Prevalence of M694V in Patients With Ankylosing Spondylitis: Additional Evidence for a Link With Familial Mediterranean Fever2010In: Arthritis and Rheumatism, ISSN 0004-3591, E-ISSN 1529-0131, Vol. 62, no 10, p. 3059-3063Article in journal (Refereed)
    Abstract [en]

    Objective. To assess whether there is a statistically significant difference in the frequency of common MEFV allele variants in patients with ankylosing spondylitis (AS) as compared with control patients with rheumatoid arthritis (RA) and with healthy control subjects. Methods. Sixty-two patients with AS, 50 healthy control subjects, and 46 patients with RA were assessed for the presence of MEFV variants. Exon 10 was analyzed by direct sequencing. E148Q was analyzed by restriction endonuclease enzyme digestion (REED) or by direct sequencing when REED analysis failed. Results. The allele frequency of all MEFV variants in the AS group was significantly higher than that in the pooled control group of healthy subjects plus RA patients (15.3% versus 6.8%; P = 0.021). M694V was the only variant that was significantly more common in the AS group than in the combined or individual control groups (P = 0.026 for AS patients versus healthy controls, P = 0.046 for AS patients versus RA patient controls, and P = 0.008 for AS patients versus healthy and RA patient control groups). The carriage rate of M694V was also significantly higher in the AS patient group than in the combined control group (odds ratio 7.0, P = 0.014). Neither M694V nor any other MEFV variant showed a correlation with most of the disease-related measures examined. Conclusion. We found an increased frequency of MEFV variants in AS patients as compared with healthy controls and with RA patient controls. This was primarily due to the presence of M694V. The roles of other exon 10 variants, as well as the relationship between the variant status and the severity and clinical course of the disease, need to be explored in further studies that include sufficiently large sample sizes.

  • 187.
    Akula, Srinivas
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Cell and Molecular Biology. Uppsala University, Disciplinary Domain of Science and Technology, Biology, Biology Education Centre.
    Analysis of the isotype specificity of three platypus immunoglobulin Fc receptors2012Independent thesis Advanced level (degree of Master (Two Years)), 30 credits / 45 HE creditsStudent thesis
    Abstract [en]

    The host’s defense against diseases called immunity acts either via innate or adaptive defense mechanisms. Immunoglobulins (Ig’s) are important players in adaptive immunity. They have evolved both structurally and functionally during vertebrate evolution. The Fc region of Igs can interact with specific receptors on the surface of various immune cells; crosslinking of these Fc receptors can trigger a wide array of immune reactions. To trigger such reactions, higher mammals have five different classes of Igs (IgM, IgG, IgA, IgE and IgD) while amphibians, reptiles and birds have four (IgM, IgD, IgA and IgY).  Our recent studies have revealed that the early mammals (Platypus) have eight Ig isotypes (IgM, IgD IgO, IgG1, IgG2, IgA1, IgA2 and IgE) and at least four Fc receptors: FcRA, FcRB, FcRC and FcRD. In this study we investigated the specificity of three of these platypus Fc receptors to get a better picture of their isotype specificity.   

  • 188.
    Akula, Srinivas
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Cell and Molecular Biology, Microbiology. Uppsala University.
    The mast cell transcriptome and the evolution of granule proteins and Fc receptors2019Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Protection against disease-causing pathogens, known as immunity, involves numerous cells organs, tissues and their products. To able to understand the biology of immune cells (hematopoietic cells) and their role in an immune system, we have used several different methods, including transcriptome analyses, bioinformatics, production of recombinant proteins and analyses of some of them, focusing on the granule proteases by substrate phage display.

    Hematopoietic cells express surface receptors interacting with the constant region of immunoglobulins (Igs) known as Fc receptors (FcRs). These receptors play major roles in the immune system, including enhancing phagocytosis, activating antibody dependent cellular cytotoxicity and cell activation. A detailed bioinformatics analysis of FcRs reveals that the poly-Ig receptors (PIGR), FcR-like molecules and common signalling γ chain all appeared very early with the appearance of the bony fishes, and thereby represent the first major evolutionary step in FcR evolution. The FcμR, FcαμR, FcγR and FcεR receptors most likely appeared in reptiles or early mammals, representing the second major step in FcR evolution.

    Cells of several of the hematopoietic cell lineages contain large numbers of cytoplasmic granules, and serine proteases constitute the major protein content of these granules. In mammals, these proteases are encoded from four different loci: the chymase, the met-ase, the granzyme (A/K) and the mast cell tryptase loci. The granzyme (A/K) locus was the first to appear and came with the cartilaginous fishes. This locus is also the most conserved of the three. The second most conserved locus is the met-ase locus, which is found in bony fishes. The chymase locus appeared relatively late, and we find the first traces in frogs, indicating it appeared in early tetrapods.

    To study the early events in the diversification of these hematopoietic serine proteases we have analyzed key characteristics of a protease expressed by an NK-like cell in the channel catfish, catfish granzyme–like I. We have used phage display and further validated the results using a panel of recombinant substrates. This protease showed a strict preference for Met at the P1 (cleavage) position, which indicates met-ase specificity. From the screening of potential in vivo substrates, we found an interesting potential target caspase 6, which indicates that caspase-dependent apoptosis mechanisms have been conserved from fishes to mammals.

    A larger quantitative transcriptome analysis of purified mouse peritoneal mast cells, cultured mast cells (BMMCs), and mast cells isolated from mouse ear and lung tissue identified the major tissue specific transcripts in these mast cells as the granule proteases. Mast cell specific receptors and processing enzymes were expressed at approximately 2 orders of magnitude lower levels. The levels of a few proteases were quite different at various anatomical sites between in vivo and cultured BMMCs. These studies have given us a new insights into mast cells in different tissues, as well as key evolutionary aspects concerning the origins of a number of granule proteases and FcRs.

    List of papers
    1. Fc Receptors for Immunoglobulins and Their Appearance during Vertebrate Evolution
    Open this publication in new window or tab >>Fc Receptors for Immunoglobulins and Their Appearance during Vertebrate Evolution
    2014 (English)In: PLoS ONE, ISSN 1932-6203, E-ISSN 1932-6203, Vol. 9, no 5, p. e96903-Article in journal (Refereed) Published
    Abstract [en]

    Receptors interacting with the constant domain of immunoglobulins (Igs) have a number of important functions in vertebrates. They facilitate phagocytosis by opsonization, are key components in antibody-dependent cellular cytotoxicity as well as activating cells to release granules. In mammals, four major types of classical Fc receptors (FcRs) for IgG have been identified, one high-affinity receptor for IgE, one for both IgM and IgA, one for IgM and one for IgA. All of these receptors are related in structure and all of them, except the IgA receptor, are found in primates on chromosome 1, indicating that they originate from a common ancestor by successive gene duplications. The number of Ig isotypes has increased gradually during vertebrate evolution and this increase has likely been accompanied by a similar increase in isotype-specific receptors. To test this hypothesis we have performed a detailed bioinformatics analysis of a panel of vertebrate genomes. The first components to appear are the poly-Ig receptors (PIGRs), receptors similar to the classic FcRs in mammals, so called FcRL receptors, and the FcR gamma chain. These molecules are not found in cartilagous fish and may first appear within bony fishes, indicating a major step in Fc receptor evolution at the appearance of bony fish. In contrast, the receptor for IgA is only found in placental mammals, indicating a relatively late appearance. The IgM and IgA/M receptors are first observed in the monotremes, exemplified by the platypus, indicating an appearance during early mammalian evolution. Clearly identifiable classical receptors for IgG and IgE are found only in marsupials and placental mammals, but closely related receptors are found in the platypus, indicating a second major step in Fc receptor evolution during early mammalian evolution, involving the appearance of classical IgG and IgE receptors from FcRL molecules and IgM and IgA/M receptors from PIGR.

    National Category
    Biomedical Laboratory Science/Technology
    Identifiers
    urn:nbn:se:uu:diva-228481 (URN)10.1371/journal.pone.0096903 (DOI)000336838000078 ()
    Available from: 2014-07-15 Created: 2014-07-15 Last updated: 2019-04-12Bibliographically approved
    2. Granule Associated Serine Proteases of Hematopoietic Cells - An Analysis of Their Appearance and Diversification during Vertebrate Evolution
    Open this publication in new window or tab >>Granule Associated Serine Proteases of Hematopoietic Cells - An Analysis of Their Appearance and Diversification during Vertebrate Evolution
    2015 (English)In: PLoS ONE, ISSN 1932-6203, E-ISSN 1932-6203, Vol. 10, no 11, article id e0143091Article in journal (Refereed) Published
    Abstract [en]

    Serine proteases are among the most abundant granule constituents of several hematopoietic cell lineages including mast cells, neutrophils, cytotoxic T cells and NK cells. These proteases are stored in their active form in the cytoplasmic granules and in mammals are encoded from four different chromosomal loci: the chymase locus, the met-ase locus, the T cell tryptase and the mast cell tryptase locus. In order to study their appearance during vertebrate evolution we have performed a bioinformatic analysis of related genes and gene loci from a large panel of metazoan animals from sea urchins to placental mammals for three of these loci: the chymase, met-ase and granzyme A/K loci. Genes related to mammalian granzymes A and K were the most well conserved and could be traced as far back to cartilaginous fish. Here, the granzyme A and K genes were found in essentially the same chromosomal location from sharks to humans. However in sharks, no genes clearly identifiable as members of the chymase or met-ase loci were found. A selection of these genes seemed to appear with bony fish, but sometimes in other loci. Genes related to mammalian met-ase locus genes were found in bony fish. Here, the most well conserved member was complement factor D. However, genes distantly related to the neutrophil proteases were also identified in this locus in several bony fish species, indicating that this locus is also old and appeared at the base of bony fish. In fish, a few of the chymase locus-related genes were found in a locus with bordering genes other than the mammalian chymase locus and some were found in the fish met-ase locus. This indicates that a convergent evolution rather than divergent evolution has resulted in chymase locus-related genes in bony fish.

    National Category
    Medical Biotechnology (with a focus on Cell Biology (including Stem Cell Biology), Molecular Biology, Microbiology, Biochemistry or Biopharmacy)
    Identifiers
    urn:nbn:se:uu:diva-271027 (URN)10.1371/journal.pone.0143091 (DOI)000365070700134 ()26569620 (PubMedID)
    Funder
    Swedish Research Council, 621-2011-5007
    Available from: 2016-01-05 Created: 2016-01-05 Last updated: 2019-04-12Bibliographically approved
    3. Channel catfish granzyme-like I is a highly specific serine protease with metase activity that is expressed by fish NK-like cells
    Open this publication in new window or tab >>Channel catfish granzyme-like I is a highly specific serine protease with metase activity that is expressed by fish NK-like cells
    2016 (English)In: Developmental And Comparative Immunology, ISSN 0145-305X, Vol. 63, p. 84-95Article in journal (Refereed) Published
    Abstract [en]

    Here we present the extended cleavage specificity of catfish granzyme-like I, previously identified in fish NK-like cells. This protease has been characterised using substrate phage display and further validated by using a panel of recombinant substrates. A strict preference for Met in the P1 (cleavage) position, indicating metase specificity was observed. A screening of potential in vivo substrates was performed based on the derived P5-P3' consensus: Arg-Val-Thr-Gly-Met(down arrow)Ser-Leu-Val. Channel catfish caspase 6 was one very interesting potential target identified. This site was present in an adjacent position to the classic caspase activation site (Asp179 in human caspase 6). Cleavage of this site (hence potential activation) by the catfish granzyme-like I could reveal a novel mechanism of caspase 6 activation. This poses an interesting idea that the role of granzyme-like proteases in the activation of caspase dependent apoptosis mechanisms has been conserved for over 400 million years.

    Keywords
    Fish; Serine protease; Cleavage specificity; Metase; NK cell; Caspase; Evolution
    National Category
    Immunology
    Identifiers
    urn:nbn:se:uu:diva-221554 (URN)10.1016/j.dci.2016.05.013 (DOI)000380623300010 ()27216028 (PubMedID)