科研之友
微信
新浪微博
Facebook
分享链接
摘要
C-type lectins (CTLs) are important pattern recognition receptors (PRRs) that play vital roles in innate immunity. In teleosts, a number of CTLs have been reported, but their in vivo effects on host defense are still limited. In this study, a CTL homolog (SsLec1) was identified from black rockfish, Sebastes schlegelii, and its structure, expression and biological function was analyzed. The open reading frame of SsLec1 is 633 bp, with a 5'-untranslated region (UTR) of 36 bp and a 3'-UTR of 117 bp. The deduced amino acid sequence of SsLecl shares the highest overall identity (73.20%) with the CIL of Oplegnathus fasciatus. SsLecl possesses conserved CTL features, including a carbohydrate-recognition domain, four disulfide bond-forming cysteine residues, the mannose-type carbohydrate-binding motif, the conserved calcium binding sites and a putative signal peptide. The expression of SsLecl was highest in liver and could be induced by experimental infection with Listonella anguillarum. Recombinant SsLecl (rSsLecl) purified from E. coli was able to bind and agglutinate the Grain-negative fish pathogens Vibrio ichthyoenteri and Vibrio vulnificus. The agglutinating ability of rSsLecl was abolished in the presence of mannose or ethylenediaminetetraacetic acid. Further analysis showed that rSsLec1 could enhance phagocytosis by macrophages. In vivo experiments indicated that rSsLecl could inhibit bacterial infection and promote viral invasion. Taken together, these results suggest that SsLecl is a novel CTL that possesses apparent immunoregulation property and plays a critical role in host defense against pathogens invasion.
- 出版日期2016-10
- 单位中国水产科学研究院; 青岛农业大学
