两栖动物的性别决定和分化

Sex determination and sex differentiation in amphibians

性别发育是进化生物学领域备受关注的研究热点之一。性别发育主要包括性别决定和性别分化,脊椎动物的性别决定主要分为基因性别决定和环境性别决定两种模式。两栖动物的性别决定属于基因型性别决定模式,其基因型性别由受精时两性配子的性染色体决定,但性腺分化所产生的表型性别还会受环境温度和性激素的修饰。在两栖动物中性别逆转的现象普遍存在,其相关的生理和分子机制也有一定的研究。本文从性别相关基因对性别决定的影响、温度对两栖动物性别分化的影响、性激素对两栖动物性别分化的影响、温度和性激素对性别相关基因表达的影响等四方面对两栖动物性别决定和性别分化的生理和分子机制进行一定的概述,并提出了未来两栖动物性别发育研究的重点。

Sex development is one of the hot spots in evolutionary biology. It mainly includes sex determination and sex differentiation. There are two mechanisms of sex determination in vertebrates, including genotypic sex determination （GSD） and environmental sex determination （ESD）. For amphibians, GSD is a primary mechanism of sex determination, in which the sex is determined by sex chromosomes of bisexual gametes at fertilization, but there is growing evidence showing that the sex is also modified by ambient temperature and sex hormone. The phenomenon of sex reversal generally appears in amphibians, and the physiological and molecular mechanisms have been reported. Here, we summarized the physiological and molecular mechanisms of sex determination and sex differentiation in amphibians, with the focus on the influences of sexrelated genes on sex determination, the effects of temperature and sex hormone on sex differentiation and expression of sexrelated genes. Efforts were made to point out the priority in further studies of sex development in amphibians.