The Complete Mitochondrial Genomes Of Six Termites And Molecular Phylogeny Analysis

Termites,as an ancient social insect,have a long history,many species and distinct grades.Termites have a primitive and ancient position in the insect taxonomy system.The complete mitochondrial genome of Incisitermes minor,Pericapritermes nitobei,Pericapritermes gutianensis,Reticulitermes leptomandibularis,Reticulitermes periflaviceps and Reticulitermes perilabralis,are reported in this study.Phylogenetic analysis explored the genetic relationship of six termites at the genus level.The genetic diversity of six termites was analyzed by comparing the components of the termite mitochondrial genome..In this study,14 existing termite termites(11 in the NCBI database,3 experimentally measured)were used to perform multiple sequence alignment of mitochondrial genome data,and the Cytb gene fragment was found as a DNA barcode for termite identification of molecular classification.The experimental results are as follows:(1)The complete circular mitochondrial genome of Incisitermes minor,Pericapritermes nitobei,Pericapritermes gutianensis,Reticulitermes leptomandibularis,Reticulitermes periflaviceps and Reticulitermes perilabralis have length of 15920 bp,15925bp,15926 bp,15970bp?15264bp and 15224 bp.(2)By analyzing the components of the six termite mitochondrial genomes,we found that the termites of the same genus are in base composition,intergenic and overlapping regions,protein-coding gene start codon and stop codon,RNA gene and control.The districts are very similar,and the termites of different genera have obvious differences in all aspects.(3)The phylogenetic analysis results showed that the relationship between Reticulitermes leptomandibularis and Reticulitermes aculabialis was the closest,and Reticulitermes periflaviceps were closely related to Reticulitermes kanmonensis,and then merged with Reticulitermes perilabralis,Pericapritermes gutianensis and Pericapritermes nitobei was the closest,then merged with other termite of Pericapritermes,Incisitermes minor and Cryptotermes secundus was the closest.The results of NJ establishment are similar to those of ML construction,and further explore the relationship between the six termites at different genus levels and other termite species.(4)A gene fragment was obtained from the Cytb gene by multiple alignment screening,and the Cytb-2 DNA barcode fragment was analyzed as a DNA barcode using genetic distance and phylogenetic methods.In the results of genetic distance analysis,the barcoding gap ranged from 0.008 to 0.018.In the phylogenetic analysis results,the phylogenetic tree showed obvious population separation.Both methods confirmed the feasibility of the DNA barcode.The Cytb-2 DNA barcode of this study can accurately identify the species of 10 unknown species.Through this application example,the Cytb-2 fragment can be considered as a DNA barcode to identify the species of Reticulitermes.