Differential expression and ligand binding indicate alternative functions for zebrafish polymeric immunoglobulin receptor (pIgR) and a family of pIgR-like (PIGRL) proteins

Immunogenetics. 2014 Apr;66(4):267-79. doi: 10.1007/s00251-014-0759-4. Epub 2014 Jan 28.

Abstract

The polymeric immunoglobulin (Ig) receptor (pIgR) is an integral transmembrane glycoprotein that plays an important role in the mammalian immune response by transporting soluble polymeric Igs across mucosal epithelial cells. Single pIgR genes, which are expressed in lymphoid organs including mucosal tissues, have been identified in several teleost species. A single pigr gene has been identified on zebrafish chromosome 2 along with a large multigene family consisting of 29 pigr-like (PIGRL) genes. Full-length transcripts from ten different PIGRL genes that encode secreted and putative inhibitory membrane-bound receptors have been characterized. Although PIGRL and pigr transcripts are detected in immune tissues, only PIGRL transcripts can be detected in lymphoid and myeloid cells. In contrast to pIgR which binds Igs, certain PIGRL proteins bind phospholipids. PIGRL transcript levels are increased after infection with Streptococcus iniae, suggesting a role for PIGRL genes during bacterial challenge. Transcript levels of PIGRL genes are decreased after infection with Snakehead rhabdovirus, suggesting that viral infection may suppress PIGRL function.

Publication types

  • Research Support, N.I.H., Extramural

MeSH terms

  • Amino Acid Sequence
  • Animals
  • Chromosome Mapping
  • Conserved Sequence
  • Evolution, Molecular
  • Fishes / genetics
  • Fishes / immunology
  • Gene Expression
  • Humans
  • Immunity, Innate / genetics
  • Ligands
  • Mammals / genetics
  • Mammals / immunology
  • Molecular Sequence Data
  • Multigene Family
  • Phospholipids / metabolism
  • Phylogeny
  • Protein Binding
  • Protein Structure, Tertiary
  • Receptors, Polymeric Immunoglobulin / chemistry
  • Receptors, Polymeric Immunoglobulin / genetics*
  • Receptors, Polymeric Immunoglobulin / metabolism*
  • Rhabdoviridae Infections / genetics
  • Rhabdoviridae Infections / immunology
  • Rhabdoviridae Infections / metabolism
  • Sequence Homology, Amino Acid
  • Streptococcal Infections / genetics
  • Streptococcal Infections / immunology
  • Streptococcal Infections / metabolism
  • Zebrafish / genetics*
  • Zebrafish / immunology*
  • Zebrafish / metabolism
  • Zebrafish Proteins / genetics*
  • Zebrafish Proteins / immunology*
  • Zebrafish Proteins / metabolism

Substances

  • Ligands
  • Phospholipids
  • Receptors, Polymeric Immunoglobulin
  • Zebrafish Proteins