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Updated: Sep 15, 2025

Detection of Protein Ubiquitination Sites by Peptide Enrichment and Mass Spectrometry
Published on: March 23, 2020
Proteasome-derived peptides: separating the trash from the recycling
Anna Brennan1, Taylor R Church1, Seth S Margolis2
1Department of Biological Chemistry, The Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA.
Abstract:
The proteasome is an essential protein complex in all cells. Proteasomes have two main functions: protein degradation and peptide generation. While proteasome-dependent protein degradation removes proteins and is critical for cellular function, the newly generated proteasome-derived peptides, which range in size and sequence, are emerging as essential cellular effector molecules: they are expressed on MHC-I in the immune system, function as novel modulators of neuronal signaling, are involved in innate immunity and intracellular signaling, and can be metabolized further for important cellular processes. Here, we take a comprehensive look at the mechanics behind proteasome-mediated peptide generation; the function of proteasome-derived peptides in signaling and metabolism relevant to cellular biology, health, and disease; and the techniques enabling these studies.
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