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Small heat shock proteins operate as molecular chaperones in the mitochondrial intermembrane space

ABSTRACT: Mitochondria are complex organelles with different compartments, each harboring their own protein quality control factors. While the chaperones of the mitochondrial matrix have been well characterized, it is poorly understood which chaperones protect the mitochondrial intermembrane space. We show that cytosolic small heat shock proteins are imported under basal conditions into the mitochondrial intermembrane space, where they operate as molecular chaperones. To identify chaperone substrates with MS/MS, we used a molecular trap variant of HSPB1/Hsp27 (S135F mutant). Through affinity-enrichment co-immunoprecipitation we identified significantly enriched substrates versus GFP-negative control.

INSTRUMENT(S): Q Exactive

ORGANISM(S): Homo Sapiens (human)

TISSUE(S): Cell Culture

SUBMITTER: Sara Dufour

LAB HEAD: Vincent Timmerman

PROVIDER: PXD038275 | Pride | 2022-12-12

REPOSITORIES: Pride

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			Action	DRS
	E12153_2p_5898_HSPB_B1_S135F_Ctrl1.raw	Raw
	E12165_2p_5898_HSPB_GFP_Ctrl1.raw	Raw
	E12193_2p_5898_HSPB_B1_S135F_Ctrl2.raw	Raw
	E12205_2p_5898_HSPB_GFP_Ctrl2.raw	Raw
	E12245_2p_5898_HSPB_B1_S135F_Ctrl3.raw	Raw

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