Proteasomes are regulated by interferon gamma: implications for antigen processing.
Class I major histocompatibility complex (MHC) molecules present antigenic peptides of cytoplasmic origin to T cells. As the lengths of these peptides seem restricted to eight or nine amino acids, an unusual proteolytic system must play a role in antigen processing. Proteasomes, a major extralysosomal proteolytic system, are responsible for the degradation of cytoplasmic proteins. We demonstrate that several proteasomal subunits, including MHC-encoded subunits, are regulated by interferon gamma. These data and the finding that MHC-encoded and other interferon gamma-regulated proteasomal subunits are uniquely associated with proteasomes strongly suggest that the immune system has recruited proteasomes for antigen processing.
Yang
Y
Y
Department of Immunology, Scripps Research Institute, La Jolla, CA 92037.
Waters
J B
JB
Früh
K
K
Peterson
P A
PA
D000818:Animals; D000941:Antigens / Q000378:metabolism*; D002451:Cell Compartmentation; D003546:Cysteine Endopeptidases / Q000737:chemistry / Q000378:metabolism*; D015180:Electrophoresis, Gel, Two-Dimensional; D006367:HeLa Cells; D006801:Humans; D007371:Interferon-gamma / Q000502:physiology*; D007526:Isoelectric Point; D046911:Macromolecular Substances; D008285:Major Histocompatibility Complex; D051379:Mice; D008970:Molecular Weight; D009097:Multienzyme Complexes / Q000737:chemistry / Q000378:metabolism*; D046988:Proteasome Endopeptidase Complex
D000941:Antigens; D046911:Macromolecular Substances; D009097:Multienzyme Complexes; D007371:Interferon-gamma; D003546:Cysteine Endopeptidases; D046988:Proteasome Endopeptidase Complex