An antigenic peptide produced by peptide splicing in the proteasome

N Vigneron, V Stroobant, J Chapiro, A Ooms… - Science, 2004 - science.org
N Vigneron, V Stroobant, J Chapiro, A Ooms, G Degiovanni, S Morel, P van der Bruggen
Science, 2004science.org
CD8 T lymphocytes recognize peptides of 8 to 10 amino acids presented by class I
molecules of the major histocompatibility complex. Here, CD8 T lymphocytes were found to
recognize a nonameric peptide on melanoma cells that comprises two noncontiguous
segments of melanocytic glycoprotein gp100PMEL17. The production of this peptide
involves the excision of four amino acids and splicing of the fragments. This process was
reproduced in vitro by incubating a precursor peptide of 13 amino acids with highly purified …
CD8 T lymphocytes recognize peptides of 8 to 10 amino acids presented by class I molecules of the major histocompatibility complex. Here, CD8 T lymphocytes were found to recognize a nonameric peptide on melanoma cells that comprises two noncontiguous segments of melanocytic glycoprotein gp100PMEL17. The production of this peptide involves the excision of four amino acids and splicing of the fragments. This process was reproduced in vitro by incubating a precursor peptide of 13 amino acids with highly purified proteasomes. Splicing appears to occur by transpeptidation involving an acyl-enzyme intermediate. Our results reveal an unanticipated aspect of the proteasome function of producing antigenic peptides.
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