尼罗罗非鱼性别相关基因Dmrt1的RACE扩增和序列分析

RACE Amplification and Sequence Analysis of Sex-related Gene Dmrt1 in Tilapia nilotica

[目的]为研究Dmrt基因的进化、尼罗罗非鱼性别决定机制和功能提供资料。[方法]以尼罗罗非鱼精巢cDNA为模板,采用简并PCR扩增和克隆其Dmrt保守区域,并采用3′RACE反应获得Dmrt1基因全序列。[结果]尼罗罗非鱼中Dmrt保守区域长度为158 bp。尼罗罗非鱼Dmrt1基因的DM-domain与奥利亚罗非鱼、虹鳟、青鱼将、新月鱼、人、小鼠中Dmrt1基因的DM-domain和尼罗罗非鱼、奥利亚罗非鱼中DMO基因的DM-domain的核苷酸同源性分别为98.6%、87.9%、81.4%、82.1%、77.9%、77.1%、72.1%、72.1%,氨基酸同源性为100.0%9、7.8%、87.0%、87.0%、89.1%、89.1%、84.8%和84.8%。通过3′RACE反应,获得1 108 bpDmrt1的3′端序列。尼罗罗非鱼Dmrt1与奥利亚罗非鱼、虹鳟、青鱼将、新月鱼的氨基酸序列同源性分别为99.0%、62.0%、41.0%和73.0%。[结论]Dmrt1基因具有高度保守性。

[Objective] The research aimed to provide data for studying the evolution of Dmrt gene,the sexual determination mechanism and functions in Tilapia nilotica.[Method] With cDNA sequence from spermary of T.nilotica as template,the conservative region of its Dmrt was amplified and cloned by using degenerate PCR.And the whole sequence of Dmrt1 gene was obtained by using 3′RACE reaction.[Result] The length of Dmrt conservative region in T.nilotica was 158 bp.The nucleotide homology of DM-domain in Dmrt1 gene of T.nilotica with DM-domain in Dmrt1 gene of Oreochromis aurea,Salmo gairdneri,Oryzias latipes,Xiphophorus maculatus,human and mouse and that in DMO gene in T.nilotica and O.aurea were 98.6%,87.9%,81.4%,82.1%,77.9%,77.1%,72.1% and 72.1% resp.,and the amino acid homology were 100.0%,97.8%,87.0%,87.0%,89.1%,89.1%,84.8% and 84.8% resp.Through 3′RACE reaction,3′end sequence of 1 108 bp Dmrt 1 gene was obtained.The sequence homology of amino acids in Dmrt1 between T.nilotica and O.aurea,S.gairdneri,O.latipes,X.maculates were 99.0%,62.0%,41.0% and 73.0% resp.[Conclusion] Dmrt1 gene was highly conservative.