Genomic identification and characterization of the pseudoautosomal region in highly differentiated avian sex chromosomes
2014 (English)In: Nature Communications, ISSN 2041-1723, E-ISSN 2041-1723, Vol. 5, 5448- p.Article in journal (Refereed) Published
The molecular characteristics of the pseudoautosomal region (PAR) of sex chromosomes remain elusive. Despite significant genome-sequencing efforts, the PAR of highly differentiated avian sex chromosomes remains to be identified. Here we use linkage analysis together with whole-genome re-sequencing to uncover the 630-kb PAR of an ecological model species, the collared flycatcher. The PAR contains 22 protein-coding genes and is GC rich. The genetic length is 64cM in female meiosis, consistent with an obligate crossing-over event. Recombination is concentrated to a hotspot region, with an extreme rate of > 700 cM/Mb in a 67-kb segment. We find no signatures of sexual antagonism and propose that sexual antagonism may have limited influence on PAR sequences when sex chromosomes are nearly fully differentiated and when a recombination hotspot region is located close to the PAR boundary. Our results demonstrate that a very small PAR suffices to ensure homologous recombination and proper segregation of sex chromosomes during meiosis.
Place, publisher, year, edition, pages
2014. Vol. 5, 5448- p.
IdentifiersURN: urn:nbn:se:uu:diva-240243DOI: 10.1038/ncomms6448ISI: 000345909200001PubMedID: 25378102OAI: oai:DiVA.org:uu-240243DiVA: diva2:776239