稀有鮈鲫（Rare gudgeon）Sox基因的克隆及序列分析

根据人的SRY基因中HMG-box保守区设计引物，采用PCR技术在稀有鮈鲫雌雄个体基因组DNA中分别扩增，发现3个大小分别为220、700和1500bp的片段，经过克隆和测序分析，从220bp的片段中获得两个基因片段，证明为稀有鮈鲫的Sox1和Sox21基因片段，无性别差异，其DNA序列与人及斑马鱼相应Sox基因相似性分别为Sox1：80．4％和97％；Sox21：77．3％和9l％，其编码的氨基酸序列与人及斑马鱼相应SOX蛋白相似性分别为Sox：96％和98％；Sox21：88％和100％，显示了其高度的保守性．此外，从GenBank、MEBL和DDBJ数据库获得了92个已克降的物种SRY和Sox基因全长核苷酸编码序列及HMG保守区序列数据．通过对这些数据进行序列比对及策类树的构建，分析了Sox基因家族成员的分类及分子进化模式，对稀有鮈鲫的性别决定进行了探讨，为Sox基因的进化研究提供分子基础．

Clone and Sequence Analysis of Sox Genes in Rare Gudgeon(Gobiocypris rasus)

Using the primers,which specially amplify the conservative motif of the human SRY gene,we analyzed the Sox genes of Gobiocypris rasus.Three amplification bands with the length 220,700,1 500 bp respectively were observed.Two different fragments of Sox gene were selected and sequenced from fragments of the 220 bp band.There was no sex difference in the two fragments.The identity of amino acid sequence that encoded by GrSox1 to human and zebrafish is 96% and 98%.The amino acid sequence encoded by GrSox21 has about 88% and 100% identical to the human SOX21 and zebrafish SOX21.Phylogenetic analysis of 92 Sox genes including SRY genes and the encoded amino acid sequences,which were obtained from the GenBank,MEBL and DDBJ database reveals that the Sox genes were highly conserved.