Evolutionary changes in sensitivity to hormonally induced gonadal sex reversal in a frog species
Evolutionary changes in sensitivity to hormonally induced gonadal sex reversal in a frog species
复制标题
青蛙对激素诱导的性腺性逆转敏感性的进化变化
DOI：
10.1159/000445848
复制
发表时间：
2016
影响因子：
2.3
通讯作者：
Ezaz T
中科院分区：
文献类型：
--
作者：
Miura I;Ohtani H;Ogata M;Ezaz T
日本青蛙Glandirana rugosa是唯一的，因为它显示了性染色体分化和异配子性别决定的地理变异。为了阐明性腺性别分化的种群间差异的原因，我们研究了蝌蚪发育早期的性反转和性别决定相关基因的表达模式。我们发现，性反转容易在XX女性和XY男性的2种形式（西日本和东日本）的G。rugosa与祖先的同型性染色体在男性异配子性别决定。在性逆转过程中，CYP 19和/或FOXL 2的表达依赖于性腺的表型性别。与此相反，性反转不诱导ZW女性的一个异形ZW性染色体系统的人口或在XX女性或XY男性的一个异形XY性染色体系统的人口。后两个种群是进化衍生的形式。这些结果为性腺性别分化机制的进化提供了方向。最初的系统对性激素高度敏感，几乎可以完全逆转性别。从这个祖先的形式，一个新的系统进化，是耐激素，并表现出异配子性别和性染色体分化机制的变化。
The Japanese frog Glandirana rugosa is unique in that it shows geographic variation in sex chromosome differentiation and heterogametic sex determination. To elucidate the cause of interpopulation differences in gonadal sex differentiation, we investigated hormonally induced sex reversal and the expression patterns of genes associated with sex determination during early tadpole development. We found that sex reversal was easily induced in XX females and XY males of 2 forms (West-Japan and East-Japan) of G. rugosa with the ancestral homomorphic sex chromosomes under male heterogametic sex determination. During sex reversal, expression of CYP19 and/or FOXL2 was dependent on the phenotypic sex of the gonad. In contrast, sex reversal was not induced in ZW females of a population with a heteromorphic ZW sex chromosome system or in XX females or XY males in a population with a heteromorphic XY sex chromosome system. The latter 2 populations are evolutionarily derived forms. These results indicate an evolutionary direction for the gonadal sex differentiation mechanism. The original system was highly sensitive to sex hormones and allowed almost complete sex reversal. From this ancestral form, a new system evolved that was resistant to hormones and showed a change in the heterogametic sex and the sex chromosome differentiation mechanism.