MHC class I genes of the channel catfish: sequence analysis and expression

Immunogenetics. 1999 Apr;49(4):303-11. doi: 10.1007/s002510050497.

Abstract

Four cDNAs encoding the major histocompatibility complex (MHC) class I alpha chain were isolated from a channel catfish clonal B-cell cDNA library. Sequence analysis suggests these cDNAs represent three different MHC class I loci. All cDNAs encoded conserved residues characteristic of the MHC class I alpha chain: namely, those involved in peptide binding, salt bridges, disulfide bond formation, and glycosylation. Southern blot analyses of individual outbred and second-generation gynogenetic fish indicated the existence of both polygenic and polymorphic loci. Northern blot studies demonstrated that catfish B, T, and macrophage cell lines transcribed markedly higher levels of class I alpha and beta2-microglobulin (beta2m) mRNA than fibroblast cell lines. In addition, immunoprecipitation data showed that a 41 000 Mr glycoprotein (presumably class I alpha) was associated with beta2m on the surface of catfish B cells. This latter finding is the first direct evidence for the cell surface association of beta2m with the MHC class I alpha chain on teleost cells and supports the notion that functional MHC class I proteins exist in teleosts.

Publication types

  • Research Support, U.S. Gov't, Non-P.H.S.
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Amino Acid Sequence
  • Animals
  • Base Sequence
  • DNA, Complementary
  • Gene Expression
  • Genes, MHC Class I*
  • Ictaluridae / genetics*
  • Ictaluridae / immunology
  • Molecular Sequence Data
  • Multigene Family
  • Polymorphism, Genetic
  • RNA, Messenger
  • Sequence Analysis, DNA
  • Sequence Homology, Nucleic Acid
  • beta 2-Microglobulin / genetics

Substances

  • DNA, Complementary
  • RNA, Messenger
  • beta 2-Microglobulin

Associated data

  • GENBANK/AF053546
  • GENBANK/AF053547
  • GENBANK/AF053548
  • GENBANK/AF053549