The Complete Mitochondrial Genome Sequence Of Oryzias Celebensis And The Genetic Structure Of Oryzias Sinensis

Fish are the most primitive with the most species of vertebrates.They have the characteristics of high diversity,complex origin,wide distribution,and rich genetic diversity.Therefore,their systematic evolution and genetic diversity research are long-term hot spots.The genus Oryzias has the characteristics of small size and is easy to reproduce.The Japanese medaka has been studied intensively and has been developed as an important model organism.However,all medakas are non-edible,many species distributed in Southeast Asia and China lags behind.Among them,Oryzias celebensis still lacks a complete mitochondrial sequence,and Oryzias sinensis(Chinese medaka)still lacks population genetics research.In this study,transcriptome data was used to determine and annotate the complete sequence of the mitochondrial genome of Oryzias celebensis.The results showed that the full length of the mitochondrial genome sequence of Oryzias celebensis was16493bp(Genbank number:MN064715),A + T content,genes The arrangement and composition are roughly the same as other teleost fish,containing 37 genes and one control region.Among the 13 protein-coding genes,except for the COⅠ gene that uses GTG as the start codon,the other coded proteins all use ATG as the start codon.22 t RNA genes,except t RNAser,can form a complete clover-type secondary structure.The evolutionary tree constructed based on the complete sequence of the mitochondrial genome of 10 species of medaka fish showed that the phylogeny of Oryzias celebensis is close to Oryzias sarasinorum and Oryzias marmoratus,and is located in the middle and upper part of the phylogenetic tree.In this study,we acquired nine mountains of Qianxi,Caohai Lake,Baoshan,Kunming bonus garden,Jianhu,Napa lake,Lashihai Lake and Quanzhou.Analysis of the genetic diversity of 76 CO Ⅰ sequences determined by amplification in ageographical group of Chinese medaka samples.The results showed that the number of variation sites among the 601 homologous sites confirmed by multiple sequence alignment was 39,including a single 6 mutation sites.The base composition of T,C,A and G are: 31.6%,26.6%,24.2% and 17.6%,of which A + T(55.8%)is higher than C+ G(44.2%);the average genetic distance between groups is 0.000-0.035.The haplotype number of all 76 sequences was 23,the haplotype(gene)diversity was0.868,the highest haplotype diversity in the whole state population was 69.23%;the nucleotide diversity was 0.01676,and the average nucleotide difference was 10.07;Genetic differentiation and cluster analysis showed that there was a certain degree of differentiation among the nine Chinese medaka populations with a low gene flow.