Miura Ikuo, Hasegawa Yoshinori, Ito Michihiko, Ezaz Tariq, Ogata Mitsuaki
Amphibian Research Center, Hiroshima University, Higashi-Hiroshima 739-8526, Japan.
Institute for Applied Ecology, University of Canberra, Bruce, ACT 2617, Australia.
Biomolecules. 2024 Dec 9;14(12):1566. doi: 10.3390/biom14121566.
is an ancestral homologous gene of the male-determining in eutherian mammals and determines maleness in medaka fish. In the Japanese frog, , is located on the Z and W chromosomes. To assess the sex-determining function of in this frog, we investigated its expression in gonads during early tadpole development and conducted genome-editing experiments. We found that the mRNA levels in the gonads/mesonephroi were much higher in ZW females than that in ZZ males, and that the W-borne allele was dominantly expressed. A higher expression in ZW females preceded the onset of the sexually dimorphic expression of other autosomal sex differentiation genes. The Sox3 protein was detected by immunostaining in the somatic cells of early tadpole gonads around the boundary between the medulla and cortex in ZW females, whereas it was outside the gonads in ZZ males. Disrupting using TALEN, which targets two distinct sites, generated sex-reversed ZW males and hermaphrodites, whereas no sex reversal was observed in ZZ males. These results suggest that the sex-linked is involved in female determination in the ZZ-ZW sex-determining system of the frog, an exact opposite function to the male determination of medaka and eutherian .
是真兽亚纲哺乳动物中雄性决定基因的祖先同源基因，并决定青鳉鱼的雄性特征。在日本林蛙中，位于Z和W染色体上。为了评估该基因在这种青蛙中的性别决定功能，我们研究了其在蝌蚪早期发育过程中性腺中的表达，并进行了基因组编辑实验。我们发现，性腺/中肾中的mRNA水平在ZW雌性中比ZZ雄性中高得多，并且W染色体携带的等位基因呈显性表达。ZW雌性中较高的表达先于其他常染色体性别分化基因的性二态性表达开始。通过免疫染色在ZW雌性蝌蚪早期性腺髓质和皮质边界周围的体细胞中检测到Sox3蛋白，而在ZZ雄性中该蛋白位于性腺外。使用靶向两个不同位点的TALEN破坏该基因，产生了性反转的ZW雄性和雌雄同体，而ZZ雄性中未观察到性反转。这些结果表明，在青蛙的ZZ-ZW性别决定系统中，与性别连锁的该基因参与雌性决定，这与青鳉鱼和真兽亚纲的雄性决定功能正好相反。
