Jiang Y, Nie L W, Huang Z F, Jing W X, Wang L, Liu L, Dai X T
School of Life Sciences, Anhui Normal University, Provincial Key Lab of the Conservation and Exploitation Research of Biological Resources in Anhui, Wuhu, China.
Genet Mol Res. 2011;10(3):1545-57. doi: 10.4238/vol10-3gmr1205.
The complete mitochondrial DNA (mtDNA) control regions (CR), cytochrome b (Cyt b), NADH dehydrogenase subunit 4 (ND4) and cytochrome coxidase subunit I (CO I) genes of four Asian freshwater turtles, Mauremys japonica, Ocadia sinensis, M. mutica, and Annamemys annamensis, were sequenced using universal PCR and long-PCR techniques. Combined with CR sequences of Chinemys reevesii, the composition and structure of CR of the five species were compared and analyzed. Three functional domains (TAS, CD and CSB) in CR and their conserved sequences (TAS, CSB-F, CSB-1, CSB-2, and CSB-3) were identified based on sequence similarity to those of other turtles. At the 3' end of CSB, six type motifs of variable number of tandem repeats (VNTRs) of five species were recognized, in which the TTATATTA motif may be the VNTR motif of the ancestral species of these five turtles. Comparison of nucleotide divergences among Cyt b, ND4, CO I, and CR of 11 turtle species using transitions + transversions and transversions-only methods supported the conclusion that CR evolved 2.6- to 5.7-fold faster than the other mtDNA genes. After excluding VNTRs of CR, molecular phylogenetic trees were constructed with maximum parsimony, maximum likelihood and Bayesian inference methods. The results supported an expanded clade of Mauremys, which included species formerly in Ocadia, Chinemys, Mauremys, and Annamemys; this was also reflected in the results of VNTR analysis.
利用通用PCR和长PCR技术对日本石龟、中华花龟、黄喉拟水龟和安南龟这四种亚洲淡水龟的完整线粒体DNA（mtDNA）控制区（CR）、细胞色素b（Cyt b）、烟酰胺腺嘌呤二核苷酸脱氢酶亚基4（ND4）和细胞色素c氧化酶亚基I（CO I）基因进行了测序。结合中华草龟的CR序列，对这五个物种CR的组成和结构进行了比较分析。基于与其他龟类序列的相似性，确定了CR中的三个功能域（TAS、CD和CSB）及其保守序列（TAS、CSB-F、CSB-1、CSB-2和CSB-3）。在CSB的3'端，识别出了五个物种的六种可变数目串联重复序列（VNTR）类型基序，其中TTATATTA基序可能是这五个龟类祖先物种的VNTR基序。使用转换+颠换和仅颠换方法对11种龟类的Cyt b、ND4、CO I和CR之间的核苷酸差异进行比较，支持了CR比其他mtDNA基因进化快2.6至5.7倍的结论。在排除CR的VNTR后，采用最大简约法、最大似然法和贝叶斯推断法构建了分子系统发育树。结果支持了一个扩大的闭壳龟属分支，其中包括以前属于花龟属、中华草龟属、闭壳龟属和安南龟属的物种；这也反映在VNTR分析结果中。
