title: Characterization of complement 1q binding protein of tiger shrimp, Penaeus monodon, and its C1q binding activity.
abstract: The receptor for the globular heads of C1q, C1qBP/gC1qR/p33, is a multicompartmental, multifunctional cellular protein with an important role in infection and in inflammation. In the present study, we identified and characterized the complement component 1q subcomponent binding protein (C1qBP) from the tiger shrimp Penaeus monodon (designated as PmC1qBP). The open reading frame of PmC1qBP encodes 262 amino acid residues with a conserved MAM33 domain, an arginine-glycine-aspartate cell adhesion motif, and a mitochondrial targeting sequence in the first 53 amino acids. PmC1qBP shares 32%-81% similarity with known C1qBPs and clusters with lobster gC1qR under phylogenetic analysis. The temporal PmC1qBP mRNA expression in the hepatopancreas was significantly enhanced at 9 h after Vibrio vulnificus challenge. The native PmC1qBP was expressed in the gills, hepatopancreas, ovaries, and intestines as a precursor (38 kDa) and the active peptide (35 kDa). The recombinant PmC1qBP protein was expressed in Escherichia coli BL21, and was purified using nickel-nitrilotriacetic acid agarose. A complement 1q binding assay indicated that the rC1qBP protein competitively binds to C1q in mouse serum. The data reveal that PmC1qBP is not only involved in shrimp immune responses to pathogenic infections, but also cross-binding to the mouse C1q.
authors.affiliation: Key Laboratory of South China Sea Fishery Resources Exploitation & Utilization, Ministry of Agriculture, The South China Sea Fisheries Research Institute, Chinese Academy of Fishery Sciences, Guangzhou 510300, PR China.
authors.forename: Lishi
authors.initials: L
authors.lastname: Yang
authors.forename: Xianjun
authors.initials: X
authors.lastname: Liu
authors.forename: Wenjing
authors.initials: W
authors.lastname: Liu
authors.forename: Xiaolan
authors.initials: X
authors.lastname: Li
authors.forename: Lihua
authors.initials: L
authors.lastname: Qiu
authors.forename: Jianhua
authors.initials: J
authors.lastname: Huang
authors.forename: Shigui
authors.initials: S
authors.lastname: Jiang
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D060829:Arthropod Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D001483:Base Sequence; D015153:Blotting, Western; D003001:Cloning, Molecular; D015922:Complement C1q / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D004926:Escherichia coli / Q000235:genetics; D051379:Mice; D008969:Molecular Sequence Data; D033561:Penaeidae / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D010802:Phylogeny; D060888:Real-Time Polymerase Chain Reaction; D011994:Recombinant Proteins / Q000235:genetics / Q000378:metabolism; D016415:Sequence Alignment / Q000662:veterinary; D014733:Vibrio / Q000276:immunology / Q000502:physiology
chemical_list: D060829:Arthropod Proteins; D011994:Recombinant Proteins; D015922:Complement C1q