Expression And Regulation Of Sex Pheromone Receptor Gene Bmu009839 In Bursaphelenchus Mucronatus

B.mucronatus is a parasitic nematode of pine that is widely distributed in the natural pine forests of Asia and Europe.Its morphology and biology are similar with B.xylophilus,the causal agent of pine wilt disease.In the past,it has never been considered that B.mucronatus is pathogenic.However,in recently,more and more studies have found that some stains of B.mucronatus also have strong pathogenicity.The level of mating efficiency and reproductive ability are closely related to whether the B.mucronatus are pathogenic.Sex pheromones,which are important substances used to attract females and males,plays an important role in the sexual behavior of B.mucronatus.To date,The research on B.mucronatus is rarely on molecular level and pathogenic mechanisms of themselves.Our group predicted some sex pheromone receptor genes related to mating behavior after transcriptome sequencing and analysis of B.mucronatus.Bmu009839 gene is one of them.In this study,we cloned the Bmu009839,and deeply explored the spatio-temporal dynamic expression characteristics and biological functions of the gene.The main results and conclusions are as follows.1.The results of bioinformatics analysis show that the protein expressed by the Bmu009839 in B.mucronatus was a G protein-coupled receptor,and the ntr-1 gene of C.elegans had the highest similarity to Bmu009839.2.The results of in situ hybridization and qPCR showed that the Bmu009839 gene is expressed in the whole developmental stage of B.mucronatus,and is stably expressed in the muscle cells,gonads and intestinal canal,which the expression of the gene was the highest at the adult stage,about 5.5 times the sum of other age expressions.3.RNAi results showed that Bmu009839 genes were involved in the regulation of growth and development,mating behavior and reproductive ability from embryonic stage to adult stage.a.Bmu009839 genes play an important role in embryonic and J2 stage ontogeny: after interfering with Bmu009839 genes,Embryonic hatching rate decreased significantly(Treatment hatching rate: 29.17% ±7.47%,Control hatching rate: 89.15% ± 3.73%),J2 developmental abnormalities,its manifested as abdominal swelling,tail constriction.b.The Bmu009839 gene are mainly involved in the regulation of mating behavior and fecundity of B.mucronatus from J3 to adult stage,and the regulation effect in males is stronger than that in females.With the increase of age in B.mucronatus,the regulation effect of Bmu009839 gene will become more and more significant: Bmu009839 gene interference during the J3 period,Only male mating accuracy is affected,And during the J4 period,the oviposition rate of females and males decreased,(Treatment:49.02%± 5.18%,Control:81.36% ± 0.35%);During the adult period,The male’s spicule can’t work,and the movement of females becomes sluggish.Besides,The oviposition rate of females and males also decreased significantly(Treatment:28.74% ± 7.42%,Control:71.37% ± 1.43%).Other than that,the average oviposition in the male treatment group decreased to 1/4 of the control group.According to the above results,we believe that Bmu009839 gene has an important regulatory function in the early ontogeny and late reproduction of,and we consider it as a sex pheromone receptor gene.It lays the foundation for the study of B.mucronatus at the molecular level.