title: Molecular cloning, expression of a galectin gene in Pacific white shrimp Litopenaeus vannamei and the antibacterial activity of its recombinant protein.
abstract: Galectins play crucial roles in innate immune responses in invertebrate by recognizing and eliminating microinvaders. In this study, a cDNA encoding a galectin in the Pacific white shrimp (L. vannamei) was identified and characterized. A recombinant variant of this lectin, rLvgalectin, was expressed in the model organism P. pastoris and its expression was confirmed by Western blot. Biochemical assays indicated that the recombinant protein antibacterial rLvgalectin activity and was expressed in all of the organism's tested tissues Injection of the bacterium V. alginolyticus into L. vannamei induced hemocytes upregulation of Lvgalectin. The recombinant Lvgalectin protein (rLvgalectin) could bind various microorganism including Gram-positive bacteria, Gram-negative bacteria and yeast. And it revealed antimicrobial activity against the test Gram-positive bacteria, Gram-negative bacteria, but did not inhibit the growth of fungus Pichia pastoris. Moreover, rLvgalectin could significantly enhance the clearance activity of V. alginolyticus in vivo. In vivo challenge experiments showed that the recombinant rLvgalectin protein can significantly reduce the mortalities of V. alginolyticus injection. Furthermore, Compared to their wild-type counterparts, Lvgalectin-silenced shrimp exhibited increased mortality and hemocyte apoptosis, decreased bacterial clearance ability and total hemocyte counts, and stronger expression of Lvp53, LvproPO, LvPEN3, and LvCrustin following V. alginolyticus challenge. Taken together, these results suggest that galectin is important in the innate immune response of shrimp to pathogens infection.
authors.affiliation: Key Laboratory of Ecology and Environmental Science in Guangdong Higher Education, Guangdong Provincial Key Laboratory for Healthy and Safe Aquaculture, College of Life Science, South China Normal University, Guangzhou 510631, PR China.
authors.forename: Gui-Hong
authors.initials: GH
authors.lastname: Cha
authors.affiliation: Key Laboratory of Ecology and Environmental Science in Guangdong Higher Education, Guangdong Provincial Key Laboratory for Healthy and Safe Aquaculture, College of Life Science, South China Normal University, Guangzhou 510631, PR China.
authors.forename: Yuan
authors.initials: Y
authors.lastname: Liu
authors.affiliation: Key Laboratory of Ecology and Environmental Science in Guangdong Higher Education, Guangdong Provincial Key Laboratory for Healthy and Safe Aquaculture, College of Life Science, South China Normal University, Guangzhou 510631, PR China.
authors.forename: Ting
authors.initials: T
authors.lastname: Peng
authors.affiliation: Key Laboratory of Ecology and Environmental Science in Guangdong Higher Education, Guangdong Provincial Key Laboratory for Healthy and Safe Aquaculture, College of Life Science, South China Normal University, Guangzhou 510631, PR China.
authors.forename: Ming-Zhu
authors.initials: MZ
authors.lastname: Huang
authors.affiliation: Key Laboratory of Ecology and Environmental Science in Guangdong Higher Education, Guangdong Provincial Key Laboratory for Healthy and Safe Aquaculture, College of Life Science, South China Normal University, Guangzhou 510631, PR China.
authors.forename: Chen-Ying
authors.initials: CY
authors.lastname: Xie
authors.affiliation: Key Laboratory of Ecology and Environmental Science in Guangdong Higher Education, Guangdong Provincial Key Laboratory for Healthy and Safe Aquaculture, College of Life Science, South China Normal University, Guangzhou 510631, PR China.
authors.forename: Yu-Chao
authors.initials: YC
authors.lastname: Xiao
authors.affiliation: Key Laboratory of Ecology and Environmental Science in Guangdong Higher Education, Guangdong Provincial Key Laboratory for Healthy and Safe Aquaculture, College of Life Science, South China Normal University, Guangzhou 510631, PR China. Electronic address: wangwn@scnu.edu.cn.
authors.forename: Wei-Na
authors.initials: WN
authors.lastname: Wang
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D017209:Apoptosis / Q000187:drug effects; D001483:Base Sequence; D002452:Cell Count; D003001:Cloning, Molecular; D037161:Galectins / Q000737:chemistry / Q000235:genetics* / Q000302:isolation & purification / Q000378:metabolism; D020869:Gene Expression Profiling; D005786:Gene Expression Regulation / Q000187:drug effects*; D055785:Gene Knockdown Techniques; D006434:Hemocytes / Q000187:drug effects / Q000378:metabolism; D008969:Molecular Sequence Data; D010140:Pacific Ocean; D033561:Penaeidae / Q000187:drug effects / Q000235:genetics* / Q000382:microbiology*; D010802:Phylogeny; D010843:Pichia / Q000378:metabolism; D011134:Polysaccharides / Q000378:metabolism; D011485:Protein Binding / Q000187:drug effects; D012330:RNA, Double-Stranded / Q000378:metabolism; D011994:Recombinant Proteins / Q000302:isolation & purification / Q000494:pharmacology*; D016415:Sequence Alignment; D020539:Sequence Analysis, Protein; D013997:Time Factors; D014018:Tissue Distribution; D014733:Vibrio / Q000187:drug effects
chemical_list: D000900:Anti-Bacterial Agents; D037161:Galectins; D011134:Polysaccharides; D012330:RNA, Double-Stranded; D011994:Recombinant Proteins
keywords: Antibacterial activity; Bacterial clearance; Litopenaeus vannamei; Lvgalectin; RNAi