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MitoStores: Chaperone-controlled protein granules store mitochondrial precursors in the cytosol - Data Set 1: Global Proteome TMT

ABSTRACT: Hundreds of mitochondrial precursor proteins are synthesized in the cytosol and imported into mitochondria in a post-translational reaction. The early stages in mitochondrial protein targeting are poorly understood. Here we show that in baker’s yeast, the cytosol has the capacity to transiently store matrix-destined precursors in dedicated deposits which we named MitoStores. MitoStores are strongly induced when the import into mitochondria is competitively inhibited by clogging the mitochondrial import sites, but also found under physiological conditions when cells grow on non-fermentable carbon sources. MitoStores contain a specific subset of nuclear encoded mitochondrial proteins, in particular those with N-terminal mitochondrial targeting sequences. The cytosolic heat shock proteins Hsp42 and Hsp104 control MitoStore formation, thereby suppressing the toxic potential of accumulating mitochondrial precursor proteins. Thus, the cytosolic protein quality system plays an active role during early stages in mitochondrial protein targeting by the coordinated localized sequestration of mitochondrial precursor proteins.

INSTRUMENT(S): Q Exactive

ORGANISM(S): Saccharomyces Cerevisiae (baker's Yeast)

SUBMITTER: Markus Räschle

LAB HEAD: Markus Räschle

PROVIDER: PXD035760 | Pride | 2023-01-17

REPOSITORIES: Pride

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			Action	DRS
	20191210_HF1_MaRa_SA_C0025_P0057B_DeltaRPN4_TMT10plex_SCX_REP01_F1.raw	Raw
	20191210_HF1_MaRa_SA_C0025_P0057B_DeltaRPN4_TMT10plex_SCX_REP01_F2.raw	Raw
	20191210_HF1_MaRa_SA_C0025_P0057B_DeltaRPN4_TMT10plex_SCX_REP01_F3.raw	Raw
	20191210_HF1_MaRa_SA_C0025_P0057B_DeltaRPN4_TMT10plex_SCX_REP02_F1.raw	Raw
	20191210_HF1_MaRa_SA_C0025_P0057B_DeltaRPN4_TMT10plex_SCX_REP02_F2.raw	Raw

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Mitoprotein-induced stress launches a global transcriptional fail-safe program

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