Molecular characterization and expression analysis of a novel dual-CRD C-type lectin in kuruma shrimp（Marsupenaeus japonicus）

• Published in: 海洋学报：英文版 Vol. 34; no. 2; pp. 74 - 83
• Main Author: ZHANG Man MAO Yong WANG Jun FENG Wenrong SONG Xiaohong SU Yongquan
• Format: Journal Article
• Language: English
• Published: 2015
• Subjects: CRD; C型凝集素; WSSV感染; 斑节虾; 日本囊对虾; 特征和; 白斑综合症病毒; 表达分析
• ISSN: 0253-505X; 1869-1099

C-type lectins are among the most significant pattern recognition receptors（PRRs） found in invertebrate. They are a class of carbohydrate-binding proteins that can recognize specific sugar moieties on the surface of pathogens. In the present study, a novel C-type lecitn（termed Mj Lectin） from kuruma shrimp Marsupenaeus japonicus was identified. The full-length c DNA of Mj Lectin was 1 245 bp with a 1 011 bp open reading frame（ORF） that encoded a polypeptide of 336 amino acid residues. Mj Lectin consisted of two tandemly arrayed carbohydrate-recognition domains（CRDs）, unlike other reported M. japonicus C-type lectins with only one CRD. It showed a high similarity to other shrimp dual-CRD lectins. Among the Ca2＋-binding Site 2, the tripeptide motif dictating the carbohydrate binding specificity was exhibited as a rare mutant LPN（Leu134-Pro135-Asn136） in CRD1 and a traditional EPN（Glu299-Pro300-Asn301） in CRD2, respectively. Mj Lectin showed a specific expression pattern in both tissue and cellular levels, for its m RNA transcript was mainly expressed in the F-cells of the hepatopancreas. After white spot syndrome virus（WSSV） challenge（3.6×108 virions/μL）, the expression of Mj Lectin in the hepatopancreas was up-regulated significantly at 48 h（P〈0.01） compared with the control group. These results suggested that Mj Lectin might be involved in the innate immune defense against WSSV infection.