凡纳滨对虾C型凝集素基因(LvCTLE)的克隆及其功能分析OA

C-type lectin(CTL)is an important pattern recognition receptor for recognizing carbohydrate structural domains.In this study we isolated and cloned a Litopenaeus vannamei C-type lectin,named LvCTLE,and analyzed its expression and function.The results of the study show that the full-length sequence of the LvCTLE gene cDNA was 1 231 bp with an open reading frame of 702 bp,encoding 233 amino acids.The LvCTLE amino acid sequence contained a signal peptide structure encoding 17 aa at the N-terminus and a sugar recognition structural domain encoding 134 aa at the C-terminus.The results showed that LvCTLE was distributed in the 9 tissues tested,with higher expression in muscle and gill tissues.After intramuscular injection of Vibrio parahaemolyticus,the expression of LvCTLE gene in both muscle and gill tissues of shrimp showed a tendency of up-regulation followed by a decrease,and the expression reached a peak at 12 h.Prokaryotically expressed recombinant rLvCTLE had Ca2+-dependent agglutination activity and could agglutinate Lactococcus garvieae,Escherichia coli,V.parahaemolyticus and V.tubiashii.D-glucose,D-galactose,D-mannose,D-fructose,maltose,sucrose and alginose all had inhibitory effects on the agglutination of rLvCTLE toward E.coli.These results suggested that LvCTLE could be involved in the immune response against bacterial challenge in the innate immune system of L.vannamei.