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MitoCPR - a surveillance pathway that protects mitochondria in response to mitochondrial import stress [human]

ABSTRACT: Mitochondrial functions are essential for cell viability and rely on protein import into the organelle. Physiological perturbations and disease conditions can lead to mitochondrial import defect. We find that in budding yeast, mitochondrial import defects result in activation of a surveillance mechanism, which we termed mitoCPR. The mitoCPR is aimed at ameliorating mitochondrial import and protecting mitochondria during import stress. This is mediated by the mitoCPR effector, Cis1, which associates with mitochondria to reduce the accumulation of mitochondrial preproteins at the organelle's surface. Clearance of preproteins depends on the AAA-ATPase Msp1 and the proteasome, suggesting that Cis1 facilitates the degradation of unimported proteins that accumulate at the mitochondrial surface. We further show that mitoCPR is critical for maintaining mitochondrial functions during mitochondrial import stress and provide evidence that it is an ancient, conserved mitochondrial protection mechanism.

ORGANISM(S): Homo sapiens

PROVIDER: GSE96726 | GEO | 2019/03/16

REPOSITORIES: GEO

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mitoCPR - a surveillance pathway that protects mitochondria in response to mitochondrial import stress

Project description:Mitochondrial functions are essential for cell viability and rely on protein import into the organelle. Various disease and stress conditions can lead to mitochondrial import defects. We find that inhibition of mitochondrial import in budding yeast activates a surveillance mechanism, mitoCPR, that is aimed at ameliorating mitochondrial import and protecting mitochondria during import stress. mitoCPR induces expression of Cis1 which associates with the mitochondrial translocase to reduce the accumulation of mitochondrial precursor proteins at the organelle surface. Clearance of precursor proteins depends on the Cis1 interacting AAA+ ATPase Msp1 and the proteasome suggesting that Cis1 facilitates degradation of un-imported proteins at the mitochondrial surface.

2018-04-20 | GSE107784 | GEO

mitoCPR - a surveillance pathway that protects mitochondria in response to mitochondrial import stress [yeast]

Project description:Mitochondrial functions are essential for cell viability and rely on protein import into the organelle. Physiological perturbations and disease conditions can lead to mitochondrial import defect. We find that in budding yeast, mitochondrial import defects result in activation of a surveillance mechanism, which we termed mitoCPR. The mitoCPR is aimed at ameliorating mitochondrial import and protecting mitochondria during import stress. This is mediated by the mitoCPR effector, Cis1, which associates with mitochondria to reduce the accumulation of mitochondrial preproteins at the organelle's surface. Clearance of preproteins depends on the AAA-ATPase Msp1 and the proteasome, suggesting that Cis1 facilitates the degradation of unimported proteins that accumulate at the mitochondrial surface. We further show that mitoCPR is critical for maintaining mitochondrial functions during mitochondrial import stress and provide evidence that it is an ancient, conserved mitochondrial protection mechanism.

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mitoCPR - a surveillance pathway that protects mitochondria in response to mitochondrial import stress

Project description:mitoCPR - a surveillance pathway that protects mitochondria in response to mitochondrial import stress

| PRJNA421360 | ENA

mitoCPR - a surveillance pathway that protects mitochondria in response to mitochondrial import stress

Project description:mitoCPR - a surveillance pathway that protects mitochondria in response to mitochondrial import stress

| PRJNA379466 | ENA

Mitochondrial protein import stress augments alpha-synuclein aggregation and neurodegeneration independent of bioenergetics

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