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AMPK alters proteasome phosphorylation status and prevents persistent proteasome condensates

ABSTRACT: Proteasomes undergo dynamic nucleocytoplasmic translocation and phase transitions in response to glucose starvation. AMP-activated protein kinase (AMPK) is important for cytoplasmic proteasome condensate dissolution and proteasome nuclear reentry in budding yeast cells upon glucose refeeding of quiescent cells. This study demonstrates that AMPK interacts with proteasomes, and the AMPK pathway regulates proteasome phosphorylation status and condensate solubility during reversible proteasome condensate formation. AMPK and the PP1 phosphatase dynamically regulate phosphorylation of multiple proteasome subunits. Therefore, the regulation of proteasome phosphorylation by AMPK is likely to be central to proteasome biomolecular condensate formation and dissolution.

ORGANISM(S): Saccharomyces Cerevisiae

SUBMITTER: Mark Hochstrasser

PROVIDER: PXD065670 | iProX | Wed Jul 02 00:00:00 BST 2025

REPOSITORIES: iProX

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Selective microautophagy of proteasomes is initiated by ESCRT-0 and is promoted by proteasome ubiquitylation

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