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20S proteasome digestion of HeLa cell extracts

ABSTRACT: The 20S proteasome is responsible for the catalytic activity of all proteasome complexes. Structural constraints mean that only unfolded, extended polypeptide chains may enter the catalytic core of the 20S proteasome. Here we conducted a comprehensive analysis of the 20S CP substrates in-vitro. We revealed that the 20S CP substrates are highly structually disordered. The 20S proteasome substrate group, termed 20S-IDPome are characterized by having significantly more protein binding partners, more post-translational modification sites and are highly enriched for RNA binding proteins. Remarkably, we found that low complexity proteins with prion-like domain which interact with GR or PR di-peptide repeats are the most preferential 20S proteasome substrates. Our finding suggests roles of the 20S proteasome in gene transcription and formation of phase-separated granules.

INSTRUMENT(S): Q Exactive

ORGANISM(S): Homo Sapiens (human)

TISSUE(S): Cell Culture

SUBMITTER: Nadav Myers

LAB HEAD: Yosef Shaul

PROVIDER: PXD010132 | Pride | 2018-07-30

REPOSITORIES: Pride

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The Disordered Landscape of the 20S Proteasome Substrates Reveals Tight Association with Phase Separated Granules.

Myers Nadav N Olender Tsviya T Savidor Alon A Levin Yishai Y Reuven Nina N Shaul Yosef Y

Proteomics 20180808 21-22

Proteasomal degradation is the main route of regulated proteostasis. The 20S proteasome is the core particle (CP) responsible for the catalytic activity of all proteasome complexes. Structural constraints mean that only unfolded, extended polypeptide chains may enter the catalytic core of the 20S proteasome. It has been previously shown that the 20S CP is active in degradation of certain intrinsically disordered proteins (IDP) lacking structural constrains. Here, a comprehensive analysis of the ...[more]

PMID: 30039638

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