虾夷扇贝不同性别类型2 个Dmrt基因DM 结构域分析

为探讨虾夷扇贝(Patinopecten yessoensis)性别决定和雌雄同体形成的分子机制,利用兼并引物,以闭壳肌基因组DNA为实验材料,扩增和克隆了虾夷扇贝Dmrt基因的DM结构域,雌性、雄性和雌雄同体3种性别共获得2个具有不同DM序列的克隆,序列长度均为141bp,分别命名为Py Dmrt3和Py Dmrt4。Py Dmrt3在3种性别类型中均有克隆,而雄性中还克隆出Py Dmrt4。结果表明,在虾夷扇贝不同性别中,Dmrt基因家族的成员可能会有不同;雄性py Dmrt3的DM结构域核苷酸和氨基酸变异频率高,其次是雌雄同体,雌性的较保守,与其他软体动物DM结构域比对,该基因家族在进化上仍然高度保守,由此推测,部分雄性可能是发生了性逆转的雌雄同体,这种较高的变异性可能也是雌雄同体的一个特点,Py Dmrt4可能参与调控雄性性别的形成。

Sequence analysis of DM domain in two Dmrt genes of three sex types of Patinopecten yessoensis

In order to study the molecular mechanism of sex determination and the causes of formation of hermaphrodite scallops in cultured Patinopecten yessoensis populations, we used degenerate PCR to amplify the Dmrt gene conserved DM domain from three sex types of genomic DNA. The PCR products have a length of 141 bp, and after DNA cloning and sequencing analysis, 2 different DM domain sequences were identified and named as PyDmrt3 and PyDmrt4. PyDmrt3 existed in three sex types, while pyDmrt4 was only cloned from male scallops genomic DNA. Differences presented in Dmrt gene sequences of different sex types. Comparing to other mollusks, the DM domain is evolutionarily conserved, while the highest variation frequency of the DNA and amino acid sequences was in male PyDmrt3, secondly in hermaphrodite PyDmrt3, but relatively high degree of sequence homology in female DM domain. It is inferred that part of males might come from hermaphrodite sex reversal, and the higher degree variation frequency may be one feature of hermaphrodite scallops. PyDmrt4 participates in the male sex determination possibly.