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Proteasome resides in and dismantles plant heat stress granules constitutively

ABSTRACT: Stress granules (SGs) are conserved reversible cytoplasmic condensates enriched with aggregation-prone proteins assembled in response to various stresses. Defects in disassembly have been associated with various neuro- and muscular degenerative diseases in humans. Plants appear to have efficient approaches to avoid the pathological conversion of SGs. However, how plants regulate SG dynamics is unclear. Here we show increase in either temperature or duration of heat stress reduces the molecular mobility of SG marker protein and suppresses SG clearance. Proteomics analysis and FRAP assays demonstrated 20S and 26S proteasomes as stable “core” components of SGs recruited early during the heat stress. Strikingly, while heat stress inhibits the activity of the overall proteasomes, it induces dramatic ubiquitylation of SG components and enhances the activities of SG-resident proteasomes, which degrade SG components even during the assembly phase. Their proteolytic activities enable the timely disassembly of SGs and secure the survival of plant cells during the recovery from heat stress.

INSTRUMENT(S): Orbitrap Fusion Lumos

ORGANISM(S): Arabidopsis Thaliana (mouse-ear Cress)

TISSUE(S): Root

SUBMITTER: Zhouli Xie

LAB HEAD: Wei Wang

PROVIDER: PXD044922 | Pride | 2024-08-22

REPOSITORIES: Pride

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	anti-47B_Col.CK.P.1.raw	Raw
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	anti-47B_Col.CK.P.2.raw	Raw
	anti-47B_Col.CK.P.2.xlsx	Xlsx
	anti-47B_Col.CK.P.3.raw	Raw

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