title: Function of two novel single-CRD containing C-type lectins in innate immunity from Eriocheir sinensis.
abstract: C-type lectin is one of the pattern-recognition proteins of the non-self-innate immune system in invertebrates. In this study, two novel C-type lectin cDNAs (EsCTL1 and EsCTL2) of Eriocheir sinensis were cloned and characterized. EsCTL1 has 169 amino acids, whereas EsCTL2 has 164 amino acids. These two lectins contain one carbohydrate-recognition domain. Phylogenetic analysis showed that EsCTL1 and EsCTL2 were not clustered with other reported lectins from crabs. EsCTL1 and EsCTL2 were expressed only in the hepatopancreas, as detected by real-time PCR. When healthy crabs were challenged with lipopolysaccharide (LPS), peptidoglycan (PGN), Staphylococcus aureus, or Aeromonas hydrophila, the expression levels of EsCTL1 and EsCTL2 were significantly regulated. The recombinant EsCTL1 and EsCTL2 can agglutinate both Gram-positive (S. aureus) and Gram-negative bacteria (Vibrio parahaemolyticus and A. hydrophila) in a Ca2+ -dependent manner. The recombinant EsCTL1 and EsCTL2 can directly bind to LPS and PGN and to all tested microorganisms (S. aureus, Bacillus thuringiensis, Bacillus subtilis, Escherichia coli, Vibrio natriegens, V. parahaemolyticus, and A. hydrophila). Furthermore, rEsCTL1 and rEsCTL2 may facilitate the clearance of V. parahaemolyticus in vivo. These results suggest that EsCTL1 and EsCTL2 may have important roles in the anti-bacterial immunity of Chinese mitten crab.
authors.affiliation: Jiangsu Key Laboratory for Biodiversity & Biotechnology and Jiangsu Key Laboratory for Aquatic Crustacean Diseases, College of Life Sciences, Nanjing Normal University, 1, Wenyuan Road, Nanjing 210046, PR China.
authors.forename: Ying
authors.initials: Y
authors.lastname: Huang
authors.affiliation: Jiangsu Key Laboratory for Biodiversity & Biotechnology and Jiangsu Key Laboratory for Aquatic Crustacean Diseases, College of Life Sciences, Nanjing Normal University, 1, Wenyuan Road, Nanjing 210046, PR China.
authors.forename: Xin
authors.initials: X
authors.lastname: Huang
authors.affiliation: Jiangsu Key Laboratory for Biodiversity & Biotechnology and Jiangsu Key Laboratory for Aquatic Crustacean Diseases, College of Life Sciences, Nanjing Normal University, 1, Wenyuan Road, Nanjing 210046, PR China.
authors.forename: Zheng
authors.initials: Z
authors.lastname: Wang
authors.affiliation: Jiangsu Key Laboratory for Biodiversity & Biotechnology and Jiangsu Key Laboratory for Aquatic Crustacean Diseases, College of Life Sciences, Nanjing Normal University, 1, Wenyuan Road, Nanjing 210046, PR China.
authors.forename: Jing-Min
authors.initials: JM
authors.lastname: Tan
authors.affiliation: Jiangsu Key Laboratory for Biodiversity & Biotechnology and Jiangsu Key Laboratory for Aquatic Crustacean Diseases, College of Life Sciences, Nanjing Normal University, 1, Wenyuan Road, Nanjing 210046, PR China.
authors.forename: Kai-Min
authors.initials: KM
authors.lastname: Hui
authors.affiliation: Jiangsu Key Laboratory for Biodiversity & Biotechnology and Jiangsu Key Laboratory for Aquatic Crustacean Diseases, College of Life Sciences, Nanjing Normal University, 1, Wenyuan Road, Nanjing 210046, PR China. Electronic address: njnuwang@263.net.
authors.forename: Wen
authors.initials: W
authors.lastname: Wang
authors.affiliation: Jiangsu Key Laboratory for Biodiversity & Biotechnology and Jiangsu Key Laboratory for Aquatic Crustacean Diseases, College of Life Sciences, Nanjing Normal University, 1, Wenyuan Road, Nanjing 210046, PR China. Electronic address: renqian0402@126.com.
authors.forename: Qian
authors.initials: Q
authors.lastname: Ren
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D060829:Arthropod Proteins / Q000737:chemistry / Q000235:genetics / Q000276:immunology*; D001419:Bacteria / Q000276:immunology; D001483:Base Sequence; D003386:Brachyura / Q000235:genetics / Q000276:immunology* / Q000821:virology; D018076:DNA, Complementary / Q000235:genetics / Q000378:metabolism; D005786:Gene Expression Regulation; D043143:Hepatopancreas / Q000276:immunology / Q000378:metabolism; D007113:Immunity, Innate / Q000276:immunology*; D037181:Lectins, C-Type / Q000737:chemistry / Q000235:genetics* / Q000276:immunology* / Q000378:metabolism; D008070:Lipopolysaccharides / Q000008:administration & dosage; D008969:Molecular Sequence Data; D010457:Peptidoglycan / Q000008:administration & dosage; D010802:Phylogeny; D060888:Real-Time Polymerase Chain Reaction; D016415:Sequence Alignment
chemical_list: D060829:Arthropod Proteins; D018076:DNA, Complementary; D037181:Lectins, C-Type; D008070:Lipopolysaccharides; D010457:Peptidoglycan
keywords: C-type lectin; Eriocheir sinensis; Innate immunity; Pattern recognition receptor