The LBP/BPI multigenic family in invertebrates: Evolutionary history and evidences of specialization in mollusks

Dev Comp Immunol. 2016 Apr:57:20-30. doi: 10.1016/j.dci.2015.11.006. Epub 2015 Dec 1.

Abstract

LBPs (lipopolysaccharide binding proteins) and BPIs (bactericidal permeability increasing proteins) are important proteins involved in defense against bacterial pathogens. We recently discovered a novel biocidal activity of a LBP/BPI from the gastropod Biomphalaria glabrata and demonstrated its role in parental immune protection of eggs, highlighting the importance of LBP/BPIs in invertebrate immunity. Here we characterize four additional LBP/BPI from B. glabrata, presenting conserved sequence architecture and exon-intron structure. Searches of invertebrate genomes revealed that existence of LBP/BPIs is not a conserved feature since they are absent from phyla such as arthropods and platyhelminths. Analyses of LBP/BPI transcripts from selected mollusk species showed recent parallel duplications in some species, including B. glabrata. In this snail species, LBP/BPI members vary in their expression tissue localization as well as their change in expression levels after immune challenges (Gram-negative bacterium; Gram-positive bacterium or yeast). These results, together with the predicted protein features provide evidences of functional specialization of LBP/BPI family members in molluscs.

Keywords: Antimicrobial protein; Biomphalaria glabrata; Invertebrate immunity; LBP/BPI.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Acute-Phase Proteins / genetics
  • Acute-Phase Proteins / metabolism*
  • Animals
  • Antimicrobial Cationic Peptides / genetics
  • Antimicrobial Cationic Peptides / metabolism*
  • Bacterial Infections / immunology*
  • Biological Evolution
  • Blood Proteins / genetics
  • Blood Proteins / metabolism*
  • Carrier Proteins / genetics
  • Carrier Proteins / metabolism*
  • Conserved Sequence
  • Gene Duplication
  • Immunity
  • Invertebrates
  • Membrane Glycoproteins / genetics
  • Membrane Glycoproteins / metabolism*
  • Mycoses / immunology*
  • Organ Specificity
  • Snails / immunology*
  • Species Specificity
  • Transcriptome

Substances

  • Acute-Phase Proteins
  • Antimicrobial Cationic Peptides
  • Blood Proteins
  • Carrier Proteins
  • Membrane Glycoproteins
  • bactericidal permeability increasing protein
  • lipopolysaccharide-binding protein