The Effect Of Symbiotic Bacteria Wolbachia On The Mitochondrial Genetic Structure Of Two Species Of Larvae

There is a wide range of Wolbachia,an intracellular symbiotic bacterium with the same genetic pattern as mitochondrial DNA(mtDNA)in insects.The maternal genetic transmission mode affects the genetic diversity of host mtDNA,which makes mtDNA difficult to correct It reflects information on the genetic structure and species classification of the infected host population.Butterfly Wolbachia infection is very common.However,a large number of studies on the genetic structure and phylogeny of related taxa using mtDNA have rarely involved Wolbachia's detection and Wolbachia's assessment of the genetic diversity of host mtDNA.In this study,Polytremis nascens Leech(1893)and Polytremis fukia Evans(1937)were the subjects of study,and the mechanism of Wolbachia's action on host mtDNA was clarified on the classification scale of the population.The extent of the impact of Wolbachia's spread on butterfly host mtDNA was evaluated by amplifying the mitochondrial genes COI,COII,and ND5 in infected and uninfected individuals.The main conclusions obtained are as follows:1.From 67 samples of the Confucius in the West China from 14 regions of China,21 individuals were infected with Wolbachia.The infection rate was 31%.Infected individuals were mainly distributed in the southeastern population.There was no significant difference in infection rate between male and female butterflies(X~2=0.65,P>0.05).2.The genetic diversity of individuals infected with Conroe in China was significantly lower than that in uninfected individuals.Simultaneously,the mitochondria in infected individuals did not show a neutral evolution(Tajima's D value=-2.3303,Fu's F values=-3.7068).The analysis of molecular variance showed that the differences in mitochondrial diversity existed mainly between infected individuals and uninfected individuals(FST=0.6064).Mismatch analysis showed that there was a different diffusion pattern between infected individuals and all individuals.The above evidence suggests that Wolbachia may have recently acquired in West China The phenomenon of?selective clearance?was caused in the butterfly infection population,which disturbed the population mtDNA diversity to a certain extent.Phylogenetic analysis showed that the mitochondrial haplotype was divided into three branches,one for Wolbachia-infected individuals and the other two for non-infected individuals,corresponding to the Midwest population and the Southeast population,respectively.Haplotype network maps,geographical distribution and population analysis revealed that haplotype 1 is an ancestral haplotype,and the Chinese punctate population is expanding.3.Phylogenetic analysis showed that the mitochondrial haplotype was divided into three branches,one for Wolbachia infected individuals and the other two for non-infected individuals,corresponding to the Midwest population and the Southeast population,respectively.The haplotype network map,geographical distribution and population analysis revealed that haplotype 1 is an ancestral haplotype,and the Chinese phenocrystodea punctata was in an expansion phase.4.Thirty-two infected individuals from 7 areas in our country were detected in 15butterflies.The infection rate was 47%.The female infection rate was 69%(11/16),and the male infection rate was 25%(4/16).The female butterfly infection rate is higher than that of the male butterfly.We amplified the Wolbachia cell division protein gene ftsZ.We found that Wolbachia belongs to the A supergroup and that there are two types of wFuk1 and wFuk2.The genetic diversity of individuals infected with wFuk1 was also significantly lower than that of uninfected individuals.At the same time,these individuals were all females,suggesting that the strain w Fuk1 may cause killing effects.