Repeated translocation of a supergene underlying rapid sex chromosome turnover in Takifugu pufferfish.

Autor: Kabir, Ahammad, Ieda, Risa, Sho Hosoya, Daigaku Fujikawa, Kazufumi Atsumi, Shota Tajima, Aoi Nozawa, Takashi Koyama, Shotaro Hirase, Osamu Nakamura, Mitsutaka Kadota, Osamu Nishimura, Shigehiro Kuraku, Yasukazu Nakamura, Hisato Kobayashi, Atsushi Toyoda, Satoshi Tasumi, Kiyoshi Kikuchi
Předmět:
Zdroj: Proceedings of the National Academy of Sciences of the United States of America; 6/7/2022, Vol. 119 Issue 23, p1-11, 70p
Abstrakt: Recent studies have revealed a surprising diversity of sex chromosomes in vertebrates. However, the detailed mechanism of their turnover is still elusive. To understand this process, it is necessary to compare closely related species in terms of sex-determining genes and the chromosomes harboring them. Here, we explored the genus Takifugu,in which one strong candidate sex-determining gene, Amhr2, has been identified. To trace the processes involved in transitions in the sex-determination system in this genus, we studied 12 species and found that while the Amhr2 locus likely determines sex in the majority of Takifugu species, three species have acquired sex-determining loci at different chromosomal locations. Nevertheless, the generation of genome assemblies for the three species revealed that they share a portion of the male-specific supergene that contains a candidate sex-determining gene, GsdfY, along with genes that potentially play a role in male fitness. The shared supergene spans ~100 kb and is flanked by two duplicated regions characterized by CACTA transposable elements. These results suggest that the shared supergene has taken over the role of sex-determining locus from Amhr2 in lineages leading to the three species, and repeated translocations of the supergene underlie the turnover of sex chromosomes in these lineages. These ?ndings highlight the underestimated role of a mobile supergene in the turnover of sex chromosomes in vertebrates. [ABSTRACT FROM AUTHOR]
Databáze: Complementary Index