大足鼠耳蝠短波视蛋白基因的RACE扩增及其进化分析  

Short Wavelength-sensitive (SWS) Opsin Gene in Myotis ricketti:RACE Amplification and Evolutionary Analysis

作　　者：茹炳华[1] 周莹莹[1] 李婵娟[1] 王力[1] 赵华斌[1,2] 

机构地区：[1]华东师范大学生命科学学院,上海200062 [2]中国科学院动物研究所,北京100101

出　　处：《动物学杂志》2008年第6期43-50,共8页Chinese Journal of Zoology

基　　金：华东师范大学985工程重点资助项目

摘　　要：根据几种哺乳动物的短波视蛋白基因的比对结果,在保守区设计两条基因特异引物扩增大足鼠耳蝠(Myotis ricketti)的短波视蛋白基因,用cDNA末端快速扩增技术(rapid amplification of cDNA ends,RACE)扩增出其5′和3′末端序列,并结合GenBank中相关哺乳动物短波视蛋白基因编码区进行了进化分析。结果显示,该基因编码区全长为1050bp,共编码350个氨基酸,没有发现提前终止密码子,且功能区严格保守,提示是一个有功能的基因;5个关键氨基酸位点分别为52T、86F、93T、114A和118S,表明该蝙蝠的短波视蛋白对紫外光最敏感。进化分析表明,兽类的短波视蛋白基因受到正选择压力的影响;相对速率检验结果显示,大足鼠耳蝠与其他兽类的短波视蛋白基因进化速率有明显的差异。提示大足鼠耳蝠的该基因可能发生了功能特化,可能对其夜晚视觉有重要的作用。The gene special primers （GSP） were designed based on the short wavelength-sensitive （SWS） Opsin genes of primates, mice, cow and dog. Rapid amplification of cDNA ends （RACE） were used for amplifying 5′ end and 3′end sequences of SWS Opsin gene of Myotis ricketti. The results show that the gene contains 1 050 bp in the coding region, encodes 350 amino acids, and lacks premature stop codons. In comparison with other mammals, the functionally important seven-transmembrane regions of the SWS Opsin gene are highly conserved, suggesting that it is a functional gene; and the key functional sites are 52 T, 86 F, 93 T, 114 A and 118 S, respectively, implying that the SWS Opsin of M. ricketti is sensitive to the ultraviolet （UV） light. Evolutionary analysis shows that positive selection has imposed on SWS Opsin in mammals, and the evolutionary rates of this gene have significant differences between M. ricketti and other mammals inferred by relative ratio test. Our study suggests that the SWS Opsin of M. ricketti have functional specialization, and thus may play an important role in bat vision in the night.

关 键 词：大足鼠耳蝠 短波视蛋白基因 RACE 紫外光 

分 类 号：Q953[生物学—动物学]