Cloning and characterization of the homolog of mammalian lipopolysaccharide-binding protein and bactericidal permeability-increasing protein in rainbow trout Oncorhynchus mykiss.
We cloned two cDNAs denoted as RT-LBP/BPI-1 and RT-LBP/BPI-2, respectively, which were derived from the mRNA of head kidney from rainbow trout. They showed structural homology with LPS-binding protein (LBP) and bactericidal/permeability-increasing protein (BPI) in mammals. The full-length cDNA of RT-LBP/BPI-1 and RT-LBP/BPI-2 is 1666 and 1741 bp, respectively. Both cDNAs encoded 473 aa residues, including the amino acids conserved in mammalian LBP and BPI proteins that were assumed to be involved in LPS binding. The overall coding sequence of RT-LBP/BPI-1 has 33% amino acid homology to human LBP and 34% to human BPI, and RT-LBP/BPI-2 has 32% amino acid homology to human LBP and 33% to human BPI. Three-dimensional structure analysis by three-dimensional/one-dimensional (3D-1D) methods also demonstrated that RT-LBP/BPI-1 and RT-LBP/BPI-2 proteins showed significant similarity to human BPI, having a boomerang shape with N-terminal and C-terminal barrels. Phylogenetic analysis showed that the LBP and BPI genes seemed to be established after the divergence of mammals from teleosts. These results suggested that RT-LBP/BPI-1 and RT-LBP/BPI-2 may be a putative ortholog for mammalian LBP and/or BPI genes. This is the first study to identify the LBP family genes from nonmammalian vertebrates.
Inagawa
Hiroyuki
H
Institute for Health Sciences, Tokushima Bunri University, Tokushima, Japan.
Honda
Teruko
T
Kohchi
Chie
C
Nishizawa
Takashi
T
Yoshiura
Yasutoshi
Y
Nakanishi
Teruyuki
T
Yokomizo
Yuichi
Y
Soma
Gen-Ichiro
G
D000209:Acute-Phase Proteins; D000595:Amino Acid Sequence; D000818:Animals; D023181:Antimicrobial Cationic Peptides; D001483:Base Sequence; D001798:Blood Proteins / Q000737:chemistry / Q000235:genetics*; D015139:Blotting, Southern; D002352:Carrier Proteins / Q000737:chemistry / Q000235:genetics*; D003001:Cloning, Molecular; D018076:DNA, Complementary / Q000302:isolation & purification; D008070:Lipopolysaccharides / Q000494:pharmacology; D008562:Membrane Glycoproteins; D008565:Membrane Proteins; D008969:Molecular Sequence Data; D017686:Oncorhynchus mykiss; D010802:Phylogeny; D000099231:Lipopolysaccharide-Binding Protein
D000209:Acute-Phase Proteins; D023181:Antimicrobial Cationic Peptides; D001798:Blood Proteins; D002352:Carrier Proteins; D018076:DNA, Complementary; D008070:Lipopolysaccharides; D008562:Membrane Glycoproteins; D008565:Membrane Proteins; D000099231:Lipopolysaccharide-Binding Protein; C021623:bactericidal permeability increasing protein