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.
ABSTRACT
Objective To analyze the genetic diversity of Pomacea canaliculata based on the mitochondria DNA cytochrome c oxidase subunitⅠ(mtDNA COⅠ)gene as a molecular marker in Lincang City of Yunnan Province,so as to provide the scien-tific data for monitoring Angiostrongylus cantonensis in local areas. Methods The genotypes and polymorphisms of 38 speci-mens of P.canaliculata collected from Mengding Town of Lincang City were analyzed by sequencing COⅠgene.The phylogenet-ic tree and genetic distances were produced based on the haplotypes from GenBank and the present study by using the neighbour-joining method with the software MEGA version 6.06. Results Totally 31 sequences were acquired in the present study and they produced 3 unique haplotypes.Haplotype 1 showed a higher frequency compared to the others and it accounted for 83.9 % (26/31).The data showed that the least genetic distances ranged from 0 to 0.052 between P.canaliculata and 3 haplotypes,as well as the largest genetic distances ranged from 0.021 to 0.239 between Pila conica and 3 haplotypes.Otherwise,the analysis of the phylogenetic trees based on COⅠgene sequences of P.canaliculata indicated that all of 3 haplotypes clustered into one big clade with that from Japan(GenBank accession number: AB433769),China(GenBank accession number: KT313034)and USA(GenBank accession number:EU523129),which owned the closet relationship amongst them.Their genetic relationships were distantly related to the GenBank's reference sequences of P.insularum(GenBank accession number:EF514942),P.cam-ena(GenBank accession number: EF515059)and so on. Conclusion There is a P. canaliculata species in Lincang City of Yunnan Province as well as a high genetic diversity amongst the acquired 3 haplotypes in this study.