title: The unique functions of tissue-specific proteasomes.
abstract: The 26S proteasome is the main protease in eukaryotes. Proteolysis occurs within the cylindrical 20S proteasome that is constitutively expressed in most tissues. However, three tissue-specific versions of the 20S proteasome have been discovered to date. The immunoproteasome is optimized to process antigens and it directs the differentiation of T helper (Th) cells. The thymoproteasome is selectively expressed in cortical epithelial cells of the thymus where it plays an essential role in the positive selection of T lymphocytes. Finally, the spermatoproteasome is found in the testes where it is required during spermatogenesis. Here, we outline how tissue-specific proteasomes adapt to functional needs in their respective tissues and how their selective inhibition may be used to interfere with autoimmune diseases and cancer.
authors.affiliation: Division of Immunology, Department of Biology, University of Konstanz, D-78457 Konstanz, Germany.
authors.forename: Andrea
authors.initials: A
authors.lastname: Kniepert
authors.affiliation: Division of Immunology, Department of Biology, University of Konstanz, D-78457 Konstanz, Germany; Biotechnology Institute Thurgau at the University of Konstanz, CH-8280 Kreuzlingen, Switzerland. Electronic address: Marcus.Groettrup@uni-konstanz.de.
authors.forename: Marcus
authors.initials: M
authors.lastname: Groettrup
mesh_terms: D000818:Animals; D017951:Antigen Presentation; D019843:Archaeal Proteins / Q000737:chemistry / Q000502:physiology; D001327:Autoimmune Diseases / Q000201:enzymology; D001426:Bacterial Proteins / Q000737:chemistry / Q000502:physiology; D002454:Cell Differentiation; D006801:Humans; D009928:Organ Specificity; D046988:Proteasome Endopeptidase Complex / Q000737:chemistry / Q000502:physiology*; D020836:Protein Structure, Quaternary; D059748:Proteolysis; D057149:Ubiquitinated Proteins / Q000378:metabolism
chemical_list: D019843:Archaeal Proteins; D001426:Bacterial Proteins; D057149:Ubiquitinated Proteins; D046988:Proteasome Endopeptidase Complex
keywords: antigen presentation; immunoproteasome; spermatoproteasome; thymoproteasome; ubiquitin