简介：InsectshavealargefamilyofC-typelectinsinvolvedincelladhesion,pathogenrecognitionandactivationofimmuneresponses.Inthisstudy,32transcriptsencodingC-typelectindomainproteins(CTLDPs)wereidentifiedfromtheThitarodesxiaojinensistranscriptome.Accordingtotheirdomainstructures,sixCTLDPswithonecarbohydraterecognitiondomain(CRD)wereclassifiedintotheCTL-Ssubfamily.Theother23CTLDPswithtwoCRDsweregroupedintotheimmulectin(IML)subfamily.TheremainingthreewithextraregulatorydomainsweresortedintotheCTL-Xsubfamily.PhylogeneticanalysisshowedthatCTL-SandCTL-Xmembersfromdifferentinsectscouldformorthologousgroups.Incontrast,noT.xiaojinensisIMLorthologueswerefoundinotherinsects.Remarkablelineage-specificexpansioninthissubfamilywasobservedreflectingthattheseCTLDPs,asimportantreceptors,haveevolveddiversifiedmembersinresponsetoavarietyofmicrobes.PredictionofbindingligandsrevealedthatT.xiaojinensis,acoldadaptedspecies,conservedtheabilityofCRDstocombinewithCa^2+tokeepitsreceptorsfromfreezing.ComparativeanalysisofinductionofCTLDPgenesafterdifferentimmunechallengesindicatedthatIMLsmightplaycriticalrolesinimmunedefenses.ThisstudyexaminedT.xiaojinensisCTLDPsandprovidesabasisforfurtherstudiesoftheircharacteristics.