Evolutionarily conserved pachytene piRNA loci are highly divergent among modern humans
AuthorsOzata, Deniz M.
Zamore, Phillip D.
UMass Chan AffiliationsGraduate School of Biomedical Sciences
Program in Bioinformatics and Integrative Biology
RNA Therapeutics Institute
KeywordsBiochemistry, Biophysics, and Structural Biology
Ecology and Evolutionary Biology
MetadataShow full item record
AbstractIn the fetal mouse testis, PIWI-interacting RNAs (piRNAs) guide PIWI proteins to silence transposons but, after birth, most post-pubertal pachytene piRNAs map to the genome uniquely and are thought to regulate genes required for male fertility. In the human male, the developmental classes, precise genomic origins and transcriptional regulation of postnatal piRNAs remain undefined. Here, we demarcate the genes and transcripts that produce postnatal piRNAs in human juvenile and adult testes. As in the mouse, human A-MYB drives transcription of both pachytene piRNA precursor transcripts and messenger RNAs encoding piRNA biogenesis factors. Although human piRNA genes are syntenic to those in other placental mammals, their sequences are poorly conserved. In fact, pachytene piRNA loci are rapidly diverging even among modern humans. Our findings suggest that, during mammalian evolution, pachytene piRNA genes are under few selective constraints. We speculate that pachytene piRNA diversity may provide a hitherto unrecognized driver of reproductive isolation.
Nat Ecol Evol. 2020 Jan;4(1):156-168. doi: 10.1038/s41559-019-1065-1. Epub 2019 Dec 23. Link to article on publisher's site
Permanent Link to this Itemhttp://hdl.handle.net/20.500.14038/25870
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