实验室驯化时长对埃及伊蚊肠道菌群的影响

Effects of laboratory domestication duration on the gut microbiota of Aedes aegypti

目的研究实验室驯化时长对蚊虫肠道菌群的影响,揭示肠道微生物的变化规律,更系统地阐明蚊虫肠道微生物与虫媒病原体传播、蚊虫抗药性的关系,为微生物与蚊虫相互作用提供新见解。同时了解不同蚊虫地理株肠道微生物的组成,为后续肠道微生物功能研究选择合适的种群提供参考。方法对实验室养殖不同时长的5株埃及伊蚊中肠微生物进行细菌核糖体16S全长扩增与宏基因组测序,通过生物信息学分析5株蚊虫携带微生物的组成、丰度、多样性和相关性,并对比了不同样本中对蚊虫生长发育、病原体传播和抗药性有重要作用的特定细菌的含量。结果实验室驯化养殖时间较短的ML和CJ株多样性指数高于养殖时间更长的DB和SA株。所有蚊虫中肠携带微生物主要来源于变形菌门(Proteobacteria)、厚壁菌门(Firmicutes)和拟杆菌门(Bacteroidota),在属水平,MH、DB和SA株埃及伊蚊携带的细菌较单一,主要为西地西菌(Cedecea)和亚细亚菌(Asaia),而养殖时间短的2个地理株ML和CJ携带的细菌种类更丰富,各菌比例更均衡。结论在实验室条件下,随着养殖时间增长,蚊虫肠道微生物多样性会降低,对蚊虫生长发育有积极作用的细菌会被保留,其比例会逐渐增大,其他大部分细菌比例会减少甚至消失。

Objective To investigate the effect of laboratory domestication duration on the gut microbiota of mosquitoes,reveal the patterns of intestinal microbiota changes,and more systematically elucidate the role of mosquito gut microbiota on the transmission of vector-borne pathogens and mosquito resistance to insecticides,providing new insights into the interaction between microorganisms and mosquitoes.Furthermore,to understand the composition of gut microbiota in different geographic strains of mosquitoes to serve as a reference for selecting suitable populations for subsequent functional studies of gut microbiota.Methods The full-length bacterial ribosomal 16S amplification and metagenomic sequencing were performed to reveal the midgut microbiota in 5 Aedes aegypti strains which had been domesticated in the laboratory for various years.The composition,abundance,diversity,and correlation of the microbiota carried by the 5 mosquito strains were analyzed through bioinformatics,and the content of specific bacteria that play an important role in mosquito growth and development,pathogen transmission,and insecticide resistance in different samples were compared.Results The ML and CJ strains,which had been domesticated for a shorter duration,exhibited higher diversity indices compared to the DB and SA strains,which had been bred for a longer time.The gut microbiota of all mosquitoes mainly consisted of Proteobacteria,Firmicutes,and Bacteroidota.At the genus level,the bacterial composition of Aedes aegypti MH,DB,and SA strains was relatively homogenous,predominantly consisting of Cedecea and Asaia,while the ML and CJ strains,domesticated for a shorter period,harbored a richer and more balanced variety of bacteria.Conclusions Under laboratory conditions,the diversity of mosquito gut microbiota will decrease with increased domestication duration.Bacteria that have a positive effect on mosquito growth and development tend to be retained and increase in proportion over time,while the proportion of most other bacteria will decrease or even disappear.