Kobayashi Tohru, Kajiura-Kobayashi Hiroko, Guan Guijun, Nagahama Yoshitaka
Department of Developmental Biology, National Institute for Basic Biology, Okazaki, Japan.
Dev Dyn. 2008 Jan;237(1):297-306. doi: 10.1002/dvdy.21409.
We examined the expression profiles of tDMRT1 and Sox9a during gonadal sex differentiation and hormone-induced sex reversal. tDMRT1 was detected in the gonial germ-cell-surrounding cells in XY fry specifically before the appearance of any signs of morphological sex differentiation, that is, sex differences in germ cell number and histogenesis, such as differentiation into intratesticular efferent duct or ovarian cavity. The signals became localized in the Sertoli and epithelial cells comprising the efferent duct during gonadal differentiation. After the induction of XY sex reversal with estrogen, tDMRT1 decreased and then disappeared completely. In contrast, tDMRT1 was expressed in the germ-cell-surrounding cells in XX sex reversal with androgen. On the other hand, Sox9a did not show sexual dimorphism before the appearance of sex differences in histogenesis and was not expressed in the efferent duct in the testis. These results suggest that tDMRT1 is a superior testicular differentiation marker in tilapia.
我们研究了tDMRT1和Sox9a在性腺性别分化和激素诱导性逆转过程中的表达谱。在XY幼鱼的生殖细胞周围细胞中，特别是在出现任何形态学性别分化迹象之前，即生殖细胞数量和组织发生的性别差异，如分化为睾丸内输出小管或卵巢腔之前，检测到了tDMRT1。在性腺分化过程中，信号定位于构成输出小管的支持细胞和上皮细胞中。在用雌激素诱导XY性逆转后，tDMRT1减少，然后完全消失。相反，在雄激素诱导XX性逆转时，tDMRT1在生殖细胞周围细胞中表达。另一方面，在组织发生的性别差异出现之前，Sox9a没有表现出性别二态性，并且在睾丸的输出小管中不表达。这些结果表明，tDMRT1是罗非鱼中一种优越的睾丸分化标志物。
