Proteasomal cleavage of substrate

Stable Identifier
Reaction [omitted]
Homo sapiens
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The 26S proteasome complex consists of the 20S catalytic core particle which harbours the proteolytically active sites and the regulatory 19S particle which is responsible for substrate interaction. This process generates a vast number (perhaps hundreds) of different peptides, depending on the length and sequence of the substrate protein. Only a small fraction of these peptides (nearly 10%) form the exact length to be presented by class I MHC; most (approximately 70%) are too short to bind. The remaining proteasome products (10-20%) are N-terminally extended precursors that require additional cleavage by cytosolic aminopeptidases for presentation by MHC class I molecules.

Literature References
PubMed ID Title Journal Year
11350924 26S proteasomes and immunoproteasomes produce mainly N-extended versions of an antigenic peptide

Rock, KL, Hilton, C, Kisselev, AF, Cascio, P, Goldberg, AL

EMBO J 2001
15224091 Generation of major histocompatibility complex class I antigens: functional interplay between proteasomes and TPPII

Kloetzel, PM

Nat Immunol 2004
15224092 Post-proteasomal antigen processing for major histocompatibility complex class I presentation

Rock, KL, Goldberg, AL, York, IA

Nat Immunol 2004
9380723 Two distinct proteolytic processes in the generation of a major histocompatibility complex class I-presented peptide

Rock, KL, Goldberg, A, Akopian, T, Craiu, A

Proc Natl Acad Sci U S A 1997
15571818 The proteasome and MHC class I antigen processing

Kloetzel, PM

Biochim Biophys Acta 2004
14734113 Proteasome and peptidase function in MHC-class-I-mediated antigen presentation

Ossendorp, F, Kloetzel, PM

Curr Opin Immunol 2004
Catalyst Activity

endopeptidase activity of 26S proteasome [cytosol]

Orthologous Events
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