Origins and functional evolution of Y chromosomes across mammals

• Verfasst von: Cortez, Diego [VerfasserIn]
• Verfasst von: Marin, Ray [VerfasserIn]
• Verfasst von: Toledo-Flores, Deborah [VerfasserIn]
• Verfasst von: Froidevaux, Laure [VerfasserIn]
• Verfasst von: Liechti, Angélica [VerfasserIn]
• Verfasst von: Waters, Paul D. [VerfasserIn]
• Verfasst von: Grützner, Frank [VerfasserIn]
• Verfasst von: Kaessmann, Henrik [VerfasserIn]
• Titel: Origins and functional evolution of Y chromosomes across mammals
• Verf.angabe: Diego Cortez, Ray Marin, Deborah Toledo-Flores, Laure Froidevaux, Angélica Liechti, Paul D. Waters, Frank Grützner & Henrik Kaessmann
• Umfang: 6 S.
• Fussnoten: Gesehen am 20.11.2018
• Titel Quelle: Enthalten in: Nature <London>
• Jahr Quelle: 2014
• Band/Heft Quelle: 508(2014), 7497, S. 488-493
• ISSN Quelle: 1476-4687
• DOI: doi:10.1038/nature13151
• Datenträger: Online-Ressource
• Sprache: eng
• K10plus-PPN: 1583860495

Abstract

Y chromosomes underlie sex determination in mammals, but their repeat-rich nature has hampered sequencing and associated evolutionary studies. Here we trace Y evolution across 15 representative mammals on the basis of high-throughput genome and transcriptome sequencing. We uncover three independent sex chromosome originations in mammals and birds (the outgroup). The original placental and marsupial (therian) Y, containing the sex-determining gene SRY, emerged in the therian ancestor approximately 180 million years ago, in parallel with the first of five monotreme Y chromosomes, carrying the probable sex-determining gene AMH. The avian W chromosome arose approximately 140 million years ago in the bird ancestor. The small Y/W gene repertoires, enriched in regulatory functions, were rapidly defined following stratification (recombination arrest) and erosion events and have remained considerably stable. Despite expression decreases in therians, Y/W genes show notable conservationof proto-sex chromosome expression patterns, although various Y genes evolved testis-specificities through differential regulatory decay. Thus, although some genes evolved novel functions through spatial/temporal expression shifts, most Y genes probably endured, at least initially, because of dosage constraints.