title: A novel C-type lectin in the black tiger shrimp Penaeus monodon functions as a pattern recognition receptor by binding and causing bacterial agglutination.
abstract: C-type lectins are pattern recognition proteins that play important roles in innate immunity in invertebrates by mediating the recognition of pathogens. In this study, a novel C-type lectin gene, PmCLec, was cloned and characterized from the black tiger shrimp Penaeus monodon. The open reading frame of PmCLec is 657 bp in length. It encodes a predicted protein of 218 amino acids with a calculated molecular mass and an isoelectric point of 24086 Da and 4.67, respectively. Sequence analysis of PmCLec showed similarity to members of the C-type lectin gene superfamily. The deduced protein contains a single carbohydrate recognition domain (CRD) and four conserved cysteine residues (Cys58, Cys126, Cys141, Cys149) that are involved in the formation of disulfide bridges. PmCLec transcripts are expressed in various tiger shrimp tissues, with the highest expression in the lymphoid organ. RNAi-mediated silencing of PmCLec resulted in higher cumulative mortality of knockdown shrimp after Vibrio harveyi infection compared to the control groups. Recombinant PmCLec was successfully expressed in the E. coli system. In the presence of Ca2+, purified rPmCLec protein binds and agglutinates Gram-positive bacteria (Staphylococcus aureus, S. hemolyticus), but only slightly binds and agglutinates E. coli and could not bind to the Gram-negative bacteria Bacillus megaterium and Vibrio harveyi. These results suggest that PmCLec functions as a pattern recognition receptor that is implicated in shrimp innate immunity.
authors.affiliation: Department of Biochemistry, Faculty of Science, Kasetsart University, 50 Ngamwongwan Road, Bangkok 10900, Thailand. Electronic address: ratree.w@ku.ac.th.
authors.forename: Ratree
authors.initials: R
authors.lastname: Wongpanya
authors.affiliation: Department of Biochemistry, Faculty of Science, Kasetsart University, 50 Ngamwongwan Road, Bangkok 10900, Thailand.
authors.forename: Panjana
authors.initials: P
authors.lastname: Sengprasert
authors.affiliation: Aquatic Molecular Genetics and Biotechnology Laboratory, Agricultural Biotechnology Research Unit, National Center for Genetic Engineering and Biotechnology (BIOTEC), National Science and Technology Development Agency, Pathum Thani 12120, Thailand.
authors.forename: Piti
authors.initials: P
authors.lastname: Amparyup
authors.affiliation: Center of Excellence for Molecular Biology and Genomics of Shrimp, Department of Biochemistry, Faculty of Science, Chulalongkorn University, 254 Phayathai Road, Bangkok 10330, Thailand.
authors.forename: Anchalee
authors.initials: A
authors.lastname: Tassanakajon
mesh_terms: D000371:Agglutination / Q000235:genetics / Q000276:immunology*; D000595:Amino Acid Sequence; D000818:Animals; D000900:Anti-Bacterial Agents / Q000494:pharmacology; D060829:Arthropod Proteins / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism; D001483:Base Sequence; D003001:Cloning, Molecular; D018076:DNA, Complementary / Q000235:genetics / Q000378:metabolism; D004926:Escherichia coli / Q000235:genetics; D006090:Gram-Negative Bacteria / Q000187:drug effects; D006094:Gram-Positive Bacteria / Q000187:drug effects; D007113:Immunity, Innate; D037181:Lectins, C-Type / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism*; D033561:Penaeidae / Q000235:genetics* / Q000276:immunology* / Q000382:microbiology; D010802:Phylogeny; D010843:Pichia / Q000187:drug effects; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D051192:Receptors, Pattern Recognition / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D011994:Recombinant Proteins / Q000235:genetics / Q000378:metabolism; D017386:Sequence Homology, Amino Acid
chemical_list: D000900:Anti-Bacterial Agents; D060829:Arthropod Proteins; D018076:DNA, Complementary; D037181:Lectins, C-Type; D012333:RNA, Messenger; D051192:Receptors, Pattern Recognition; D011994:Recombinant Proteins
keywords: C-type lectin; Innate immunity; Pattern recognition receptor; Penaeus monodon