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  • Functional dissection and assembly of a small, newly evolved, W chromosome-specific genomic region of the African clawed frog Xenopus laevis
Title: Functional dissection and assembly of a small, newly evolved, W chromosome-specific genomic region of the African clawed frog Xenopus laevis
Genetic triggers for sex determination are frequently co-inherited with other linked genes that may also influence one or more sex-specific phenotypes. To better understand how sex-limited regions evolve and function, we studied a small W chromosome-specific region of the frogXenopus laevisthat contains only three genes (dm-w,scan-w,ccdc69-w) and that drives female differentiation. Using gene editing, we found that the sex-determining function of this region requiresdm-wbut thatscan-wandccdc69-ware not essential for viability, female development, or fertility. Analysis of mesonephros+gonad transcriptomes during sexual differentiation illustrates masculinization of thedm-wknockout transcriptome, and identifies mostly non-overlapping sets of differentially expressed genes in separate knockout lines for each of these three W-specific gene compared to wildtype sisters. Capture sequencing of almost allXenopusspecies and PCR surveys indicate that the female-determining function ofdm-wis present in only a subset of species that carry this gene. These findings map out a dynamic evolutionary history of a newly evolved W chromosome-specific genomic region, whose components have distinctive functions that frequently degraded duringXenopusdiversification, and evidence the evolutionary consequences of recombination suppression.  more » « less
Award ID(s):
1912203
PAR ID:
10516152
Author(s) / Creator(s):
; ; ; ; ; ; ; ; ; ; ;
Editor(s):
Capel, Blanche
Publisher / Repository:
PLoS
Date Published:
Journal Name:
PLOS Genetics
Volume:
19
Issue:
10
ISSN:
1553-7404
Page Range / eLocation ID:
e1010990
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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