Mitochondrial DNA And Phylogenetic Analysis Of Ochotona Coreana And Ochotona Hyperborea

Ochotona is the only genus of Ochotonidae in Lagomorpha.The existing distribution area of Ochotona is composed of mountain areas of North America and Northern Asia,which is endemic to the whole northern region.It can be divided into five subgenera:Ochotona,conothoa,pika,lagotona and alienauroa.The species mainly inhabit the shrub and rock heap in mountainous area,which is very concealed and difficult to sample.So far,there are few related literature.With the development of molecular biology,more and more scholars tend to combine the traditional morphological and phylogenetic techniques and apply them to species identification,which greatly promotes the process of the taxonomic research of Ochotona.This study is the first time to complete the determination,annotation and analysis of the complete mitochondrial gene sequences of Ochotona coreana and Ochotona hyperborea,further enriching the mitochondrial genome database of Ochotona,laying a foundation for species identification and classification,revealing the taxonomic status and evolutionary relationship of Ochotona hyperborea and Ochotona coreana,and exploring the systematic position of some species of Lagomorpha,which provides a reference for the study of Lagomorpha.It provides a new molecular basis for the phylogenetic relationship of Lagomorpha that is of great significance for the phylogenetic study of Lagomorpha.CBST2019001 and DBST2019004 were identified as Ochotona coreana and Ochotona hyperborea by traditional morphological methods and molecular phylogenetic techniques.That is to say,the external morphological characteristics and skull characteristics of the specimens are used to describe,measure and compare the morphological characteristics of known species specimens,and then the mitochondrial genome and Cytb gene are used to construct the phylogenetic tree,and the molecular phylogenetic identification is carried out by calculating the genetic distance.The results of the two identification are the same.After species identification,the mitochondrial genomes of Ochotona coreana and Ochotona hyperborea were amplified and sequenced,and the characteristics of mitochondrial genomes of Ochotona coreana and Ochotona hyperborea were found and described.The complete mitochondrial genome sequences of Ochotona coreana and Ochotona hyperborea were uploaded to NCBI-Gen Bank database,The measured mt DNA sequence was uploaded to the NCBI-Gen Bank sequence database.The sequence numbers were MT017929?MW270995,and the complete mitochondrial genome sequences of22 known species of Lagomorpha and 58 Cytb sequences of 31 species of Ochotona were downloaded for bioinformatics analysis.The classification and phylogeny among the species of Lagomorpha,Leporidae and Ochotonidae genus were systematically demonstrated There is no relationship between them.The results are as follows:(1)Based on morphological feature description and measurement data analysis,Ochotona coreana and Ochotona hyperborea meet the identification characteristics of the two in the literature respectively:incisor foramen and palatal foramen are separated;there is no small oval foramen on the frontal bone;and ears.Small,round,average length less than 23 mm(17-26 mm);winter and spring hair is brown-gray;the width of the interorbital area is greater than the width of the middle of the nasal bone;there is no spot under the ears and the neck;the skull is short round;there are black stripes on the muzzle,There is no obvious gray area on the cheeks of winter hair(Ochotona coreana).CBST2019001 was identified as Ochotona coreana and DBST2019004 as Ochotona hyperborea.(2)The amplified mitochondrial genome sequence of JJ and Ochotona hyperborea enriched the basic biological information of Ochotona genus.The full length of Ochotona coreana mt DNA sequence is 17283 bp,and the full length of Ochotona hyperborea mt DNA sequence is 17063 bp.The mitochondrial genome is a double-stranded circular DNA molecule,containing 13 protein coding sequences,2rRNA sequences,22 tRNA sequences,and two non-coding regions:1 L-chain origin of replication(O_L)and 1 control region(D-loop).There are gene gaps and gene gaps,but the gaps and overlaps are small.There is a small amount of difference between the start codon and the stop codon of the encoded protein.(3)Based on the Cytb gene and the construction of the mitochondrial genome phylogenetic tree,a comparison of the tested Ochotona samples in this study showed that:the tested samples of and the known samples of Ochotona hyperborea clustered into one branch on the phylogenetic tree.Ochotona coreana and some species originally named Ochotona hyperborea clustered into one group,but the Ochotona sample collected in Tianchi of Ochotona coreana in 2017 did not cluster into one group.This shows that there are two species of Ochotona coreana in the Changbai Mountain Range,including one hidden species.Ochotona hyperborea is a species distributed in the Greater and Lesser Khingan Mountains areas of Heilongjiang.In the evolutionary tree constructed based on the mitochondrial genome,eight species of Ochotona form a monophyletic group,which has a high bootstrap value(100%)in all tests.Thirteen species of Leporidae formed a monophyletic group,which had high bootstrap values(100%)in all tests.Ochotona coreana and Ochotona hyperborea are a sister species,and merged with other Ochotona subgenus species into a branch.It is verified from the molecular level that Ochotona coreana and Ochotona hyperborea verification in the Ochotonidae and Ochotona evolutionary status.