几种游蛇的Cyt b基因片段序列分析及其演化关系

分别从蛇类药材和冷冻保存的新鲜蛇类肌肉标本中提取DNA,经PCR扩增出12种蛇共25个样品的Cyt b基因片段,并用银染测序的方法对DNA序列进行了分析.在此基础上用MEGA软件重建的系统发生树表明,研究的11种游蛇科蛇类可以分为3组:第一组为赤链蛇和水赤链游蛇,第二组为乌梢蛇和灰鼠蛇,第三组为锦蛇属的蛇,它们与第二组较近.锦蛇属是一高度分化的属,该组至少可分为两类,一类包括百花锦蛇和黑眉锦蛇;另一类包括玉斑锦蛇、棕黑锦蛇、红点锦蛇、王锦蛇和双斑锦蛇.后一类还可进一步分为3个亚组,玉斑锦蛇和棕黑锦蛇为第一亚组,红点锦蛇单独为第二亚组,王锦蛇和双斑锦蛇为第三亚组.本研究结果还表明,多年保存的陈旧药材标本可以用DNA序列分析的方法对其进行分子系统演化关系的研究.

THE EVOLUTIONARY RELATIONSHIPS OF SEVERAL COLUBRID SNAKES SUGGESTED BY SEQUENCES ANALYSIS OF CYT B GENE FRAGMENT

DNA was extracted from both snake crude drugs and frozen snake muscle samples, and the fragment of Cyt b gene were sequenced using the silver staining DNA sequencing rnethod. The phylogenetic trees reconstructed by MEGA based on the sequence data indicated that the 12 species referred here were divided into 3 groups: Innodon rufozonatum and Sinonatrix annularis was the first group, Zaocys dhumnades and Ptyas korros the second group, and the genus Elaphe the third group which had a close relationship with the second one. Elaphe was a highly differentiated genus and, at least, could be divided into two groups. One group consisted of E. moellendroffi and E. taeniura, and the other E. mandarina, E. schrenckii, E. rufodorsata, E. carinata and E. bimaculata. The second group might consist of 3 subgroups, E. mandairna and E. schrenckii subgroup, E. rufodorsata subgroup. and E. carinata and E. bimaculata subgroup. Our results also suggested that snake crude drugs stored for several years at room ternperature could be utilized for molecular evolutionary relationship analysis using DNA sequencing method.