Identification and characterization of a beta proteasome subunit cluster in the Japanese pufferfish (Fugu rubripes)

J Immunol. 2000 Oct 15;165(8):4446-52. doi: 10.4049/jimmunol.165.8.4446.

Abstract

The low molecular mass polypeptide (LMP2, LMP7, and MECL-1) genes code for beta-type subunits of the proteasome, a multimeric complex that degrades proteins into peptides as part of the MHC class I-mediated Ag-presenting pathway. These gene products are up-regulated in response to infection by IFN-gamma and replace the corresponding constitutively expressed subunits (X, Y, and Z) during the immune response. In humans, the LMP2 and LMP7 genes both reside within the class II region of the MHC (6p21.3), while MECL-1 is located at 16q22.1. In the present study, we have identified all three IFN-gamma-regulated beta-type proteasome subunits in Fugu, which are present as a cluster within the Fugu MHC class I region. We show that in this species, LMP7, LMP2, and MECL-1 are linked. Also within this cluster is an LMP2-like subunit (which seems specific to all teleosts tested to date) and a closely linked LMP7 pseudogene, indicating that within Fugu and potentially other teleosts, there has been an additional regional duplication involving these genes.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Cosmids / chemistry
  • Cosmids / isolation & purification
  • Cysteine Endopeptidases / chemistry*
  • Cysteine Endopeptidases / genetics*
  • Exons
  • Fishes, Poisonous
  • Genes
  • Humans
  • Introns
  • Major Histocompatibility Complex / genetics
  • Multienzyme Complexes / chemistry*
  • Multienzyme Complexes / genetics*
  • Multigene Family*
  • Phylogeny
  • Proteasome Endopeptidase Complex
  • Proteins / chemistry
  • Proteins / genetics
  • Viral Matrix Proteins / chemistry
  • Viral Matrix Proteins / genetics

Substances

  • EBV-associated membrane antigen, Epstein-Barr virus
  • Multienzyme Complexes
  • Proteins
  • Viral Matrix Proteins
  • Cysteine Endopeptidases
  • proteasome subunit Z
  • LMP7 protein
  • PSMB10 protein, human
  • Proteasome Endopeptidase Complex