title: Identification and characterization of two LBP/BPI genes involved in innate immunity from Hyriopsis cumingii.
abstract: Lipopolysaccharide-binding protein and bactericidal permeability-increasing protein (LBP/BPI) play crucial role in modulating cellular signals in response to Gram-negative bacteria infection. In the present study, two isoforms of LBP/BPI genes, designated as HcLBP/BPI1 and HcLBP/BPI2, respectively, were cloned from the mussel Hyriopsis cumingii by RACE approach. The full-length cDNA sequences of HcLBP/BPI1 and HcLBP/BPI2 were 1887 and 2227 bp and encoded two secreted proteins of 501 and 518 amino acid residues, respectively. The deduced amino acid of HcLBP/BPI1 and HcLBP/BPI2 contained several conserved domains, such as signal peptide, two BPI/LBP and one central domain. Phylogentic analysis further supported that HcLBP/BPI1 and HcLBP/BPI2 belonged to new members of invertebrate LBP/BPI family. The mRNA transcripts of HcLBP/BPI1 and HcLBP/BPI2 were ubiquitously expressed in all examined tissues, and the expression level of HcLBP/BPI1 was higher than that of HcLBP/BPI2. The mRNA expression of HcLBP/BPI1 in hepatopancreas and hemocytes was significantly up-regulate after Aeromonas hydrophila and LPS challenge, and HcLBP/BPI2 in hepatopancreas was only up-regulated at 6 and 12 h after LPS challenge and at 12 h after A. hydrophila challenge. In addition, the recombinant HcLBP/BPIs displayed antibacterial activity against Gram-negative bacteria, and the antibacterial index of HcLBP/BPI1 was higher than that of HcLBP/BPI2. These results indicated that HcLBP/BPI1 and HcLBP/BPI2 probably played distinct roles in bacterial mediating immune response in Mollusca.
authors.affiliation: School of Life Sciences, Nanchang University, Nanchang 330031, China.
authors.forename: Baoqing
authors.initials: B
authors.lastname: Hu
authors.affiliation: School of Life Sciences, Nanchang University, Nanchang 330031, China. Electronic address: cgwen@ncu.edu.cn.
authors.forename: Chungen
authors.initials: C
authors.lastname: Wen
authors.affiliation: College of Jiangxi Biotech Vocational, Nanchang 330200, China. Electronic address: zhming1970@aliyun.com.
authors.forename: Ming
authors.initials: M
authors.lastname: Zhang
authors.affiliation: School of Life Sciences, Nanchang University, Nanchang 330031, China.
authors.forename: Shaoqing
authors.initials: S
authors.lastname: Jian
authors.affiliation: School of Life Sciences, Nanchang University, Nanchang 330031, China.
authors.forename: Gang
authors.initials: G
authors.lastname: Yang
mesh_terms: D000209:Acute-Phase Proteins / Q000235:genetics* / Q000276:immunology; D016980:Aeromonas hydrophila / Q000502:physiology; D000595:Amino Acid Sequence; D000818:Animals; D023181:Antimicrobial Cationic Peptides / Q000235:genetics* / Q000276:immunology; D001483:Base Sequence; D001798:Blood Proteins / Q000235:genetics* / Q000276:immunology; D002352:Carrier Proteins / Q000235:genetics* / Q000276:immunology; D003001:Cloning, Molecular; D018076:DNA, Complementary / Q000235:genetics / Q000378:metabolism; D005786:Gene Expression Regulation / Q000187:drug effects / Q000235:genetics; D007113:Immunity, Innate / Q000235:genetics*; D008070:Lipopolysaccharides / Q000494:pharmacology; D008562:Membrane Glycoproteins / Q000235:genetics* / Q000276:immunology; D010802:Phylogeny; D020033:Protein Isoforms / Q000235:genetics; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D016415:Sequence Alignment; D049876:Unionidae / Q000145:classification / Q000235:genetics* / Q000276:immunology* / Q000382:microbiology; D000099231:Lipopolysaccharide-Binding Protein
chemical_list: D000209:Acute-Phase Proteins; D023181:Antimicrobial Cationic Peptides; D001798:Blood Proteins; D002352:Carrier Proteins; D018076:DNA, Complementary; D008070:Lipopolysaccharides; D008562:Membrane Glycoproteins; D020033:Protein Isoforms; D012333:RNA, Messenger; D000099231:Lipopolysaccharide-Binding Protein; C021623:bactericidal permeability increasing protein
keywords: Antibacterial activity; Expression pattern; Hyriopsis cumingii; LBP/BPI; Molecular clone