Identification of 24 Rana Species Including Rana dybowskii and Rana chensinensis Based on COⅠ Sequences / 中国实验方剂学杂志

ABSTRACT

Objective:To identify 24 <italic>Rana</italic> species such as <italic>Rana dybowskii</italic> by mitochondrial cytochrome C oxidase subunit I （<italic>CO</italic>Ⅰ） gene-based DNA barcoding and build the neighbour-joining （NJ） tree for hierarchical cluster analysis， so as to provide a basis for the identification and classification of <italic>Rana</italic> species as well as the discovery of new species. Method:<italic>R. dybowskii</italic>， <italic>R. chensinensis</italic>， <italic>R. amurensis</italic>， <italic>R. culaiensi</italic>s， and <italic>R. huanrenesis</italic>， ten for each species， were collected for DNA extraction and polymerase chain reaction （PCR） amplification<italic> </italic>and sequencing. A total of 50 <italic>CO</italic>Ⅰ gene sequences were obtained. Then 163 <italic>CO</italic>Ⅰ gene sequences for 24 species of <italic>Rana</italic> and one <italic>CO</italic>Ⅰ gene sequence for <italic>Pelophylax</italic>，<italic> Odorrana</italic>， <italic>Nidirana</italic>， <italic>Hylarana</italic>， and <italic>Amolops</italic> were harvested from GenBank. After sequence alignment by MEGA X， the parsimony-informative sites of <italic>CO</italic>Ⅰ gene sequences were analyzed and the intraspecific and interspecific genetic distances were calculated， followed by the built of NJ tree and hierarchical cluster analysis. Result:The <italic>CO</italic>Ⅰ gene sequences of 24<italic> Rana</italic> species including <italic>R. dybowskii</italic> were 554 bp in length and there were 210 parsimony-informative sites in total. The intraspecific genetic distance of each species was smaller than 2%. Except that the interspecific genetic distance between <italic>R. sangzhiensis</italic> and <italic>R. zhengi</italic> was 0.004， the genetic distances between the other species ranged from 0.024 to 0.228. <italic>R. sangzhiensis</italic> and <italic>R. zhengi</italic> were clustered into one branch and some <italic>R. dybowskii</italic> and <italic>R. uenoi</italic> into one branch. There were two separate branches for <italic>R. chensinensis</italic> and the other species were all clustered independently. Conclusion:<italic>CO</italic>Ⅰ-based DNA barcoding enabled the identification of 24 species of <italic>Rana</italic> including <italic>R.dybowskii</italic>. The findings supported that <italic>R. sangzhiensis</italic>， <italic>R. zhengi</italic>， <italic>R. coreana</italic>， and <italic>R. kunyuensis</italic> were the same species. One branch of <italic>R. chensinensis </italic>might be one of the four undownloaded species in Ranidae or a new species. The results have demonstrated that <italic>CO</italic>Ⅰ-based DNA barcoding allows not only the identification of 24 species of Rana including <italic>R. dybowskii </italic>but also the classification of ranidae species and the discovery of new species or subspecies.