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The novel mitochondrial matrix protease Ste23 is required for efficient presequence degradation and processing.

ABSTRACT: Approximately 70% of mitochondrial precursor proteins are imported from the cytosol via N-terminal presequences, which are cleaved upon exposure to the mitochondrial processing protease MPP in the matrix. Cleaved presequence peptides then need to be efficiently degraded, and impairment of this clearance step, for example, by amyloid ? peptides, causes feedback inhibition of MPP, leading ultimately to accumulation of immature precursor proteins within mitochondria. Degradation of mitochondrial peptides is performed by Cym1 in yeast and its homologue, PreP, in humans. Here we identify the novel mitochondrial matrix protease Ste23 in yeast, a homologue of human insulin-degrading enzyme, which is required for efficient peptide degradation. Ste23 and Cym1 tightly cooperate to ensure the correct functioning of the essential presequence processing machinery.

SUBMITTER: Taskin AA

PROVIDER: S-EPMC5391191 | biostudies-literature | 2017 Apr

REPOSITORIES: biostudies-literature

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The novel mitochondrial matrix protease Ste23 is required for efficient presequence degradation and processing.

Taskin Asli Aras AA Kücükköse Cansu C Burger Nils N Mossmann Dirk D Meisinger Chris C Vögtle F-Nora FN

Molecular biology of the cell 20170222 8

Approximately 70% of mitochondrial precursor proteins are imported from the cytosol via N-terminal presequences, which are cleaved upon exposure to the mitochondrial processing protease MPP in the matrix. Cleaved presequence peptides then need to be efficiently degraded, and impairment of this clearance step, for example, by amyloid β peptides, causes feedback inhibition of MPP, leading ultimately to accumulation of immature precursor proteins within mitochondria. Degradation of mitochondrial pe ...[more]

PMID: 28228553

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