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PubMed · 11062501

Two new proteases in the MHC class I processing pathway.

L Stoltze·M Schirle·G Schwarz·C Schröter·M W Thompson·L B Hersh·H Kalbacher·S Stevanovic·H G Rammensee·H Schild
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Abstract

The proteasome generates exact major histocompatibility complex (MHC) class I ligands as well as NH2-terminal-extended precursor peptides. The proteases responsible for the final NH2-terminal trimming of the precursor peptides had, until now, not been determined. By using specific selective criteria we purified two cytosolic proteolytic activities, puromycin-sensitive aminopeptidase and bleomycin hydrolase. These proteases could remove NH2-terminal amino acids from the vesicular stomatitis virus nucleoprotein cytotoxic T cell epitope 52-59 (RGYVYQGL) resulting, in combination with proteasomes, in the generation of the correct epitope. Our data provide evidence for the existence of redundant systems acting downstream of the proteasome in the antigen-processing pathway for MHC class I molecules.

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Amino Acid Chloromethyl KetonesAmino Acid SequenceAminopeptidasesAnimalsAntigens, ViralCell LineCysteine EndopeptidasesEndopeptidasesEpitopesHistocompatibility Antigens Class IHumansLigandsMiceMolecular Sequence DataMultienzyme ComplexesNucleocapsidNucleocapsid ProteinsProteasome Endopeptidase ComplexProtein Processing, Post-TranslationalVesicular stomatitis Indiana virusJournal ArticleResearch Support, Non-U.S. Gov'tResearch Support, U.S. Gov't, P.H.S.

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L Stoltze, M Schirle, G Schwarz, C Schröter, M W Thompson, L B Hersh, H Kalbacher, S Stevanovic, H G Rammensee, H Schild. 2000. Two new proteases in the MHC class I processing pathway.. https://doi.org/10.1038/80852

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