Genetic characterizations of Toll-like receptors in the brown rat and their associations with pathogen infections  

作　　者：Qianqian SU Yi CHEN Bo WANG Qingxun ZHANG Hongxuan HE 

机构地区：[1]National Research Center for Wildlife-Borne Diseases,Chinese Academy of Sciences,Institute of Zoology,Beijing,China [2]University of Chinese Academy of Sciences,Beijing,China [3]State Key Laboratory of Integrated Management of Pest Insects and Rodents,Chinese Academy of Sciences,Institute of Zoology,Beijing,China

出　　处：《Integrative Zoology》2022年第5期879-889,共11页整合动物学（英文版）

基　　金：funded by the Major Program of National Natural Science Foundation of China(No.32090023);the Strategic Priority Research Program of the Chinese Academy of Sciences(XDA19050204);the National Forestry and Grassland Administration,China,and the Chinese Academy of Sciences(CZBZX-1).

摘　　要：Toll-like receptors(TLRs)are important initiators of innate immune responses that target host-pathogen interactions.However,further research into the molecular characteristics of TLRs in wild populations is required,as well as how TLRs genetically influenced pathogen infections in the brown rat(Rattus norvegicus).Here,we explored the genetic characterization and evolution of 2 sensing nucleic acid TLRs(TLR7 and TLR8)and 2 sensing nonnucleic acid TLRs(TLR2 and TLR4)in the wild brown rat,and assessed their associations with 2 RNA viruses(Seoul hantavirus and rat hepatitis E virus(HEV))and 2 bacteria(Leptospira and Bartonella).In these 4 TLRs,we discovered a total of 16 variants.Furthermore,TLR8 had high genetic diversity among 7 variants,while TLR2 had low genetic diversity with only 1 variant.According to selective pressure analyses,TLR4,TLR7,and TLR8 genes evolved under purifying selection.Interestingly,significant associations were found between 3 TLR8 variants and HEV infection,as well as 1 TLR2 variant and Bartonella infection.Overall,our findings provided a glimpse into the genetic characterization of TLRs in the brown rat,and further demonstrated that TLR2 and TLR8 genetic variations were related to Bartonella and HEV infection,respectively.Especially,TLR8 may be a good candidate immune gene for future research on molecular ecology and functional adaptation in wild populations.

关 键 词：BARTONELLA brown rats hepatitis E virus POLYMORPHISM SUSCEPTIBILITY Toll-like receptors 

分 类 号：Q78[生物学—分子生物学]