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Mitochondrial Lon protease is a gatekeeper for proteins newly imported into the matrix.

ABSTRACT: Human ATP-dependent Lon protease (LONP1) forms homohexameric, ring-shaped complexes. Depletion of LONP1 causes aggregation of a broad range of proteins in the mitochondrial matrix and decreases the levels of their soluble forms. The ATP hydrolysis activity, but not protease activity, of LONP1 is critical for its chaperone-like anti-aggregation activity. LONP1 forms a complex with the import machinery and an incoming protein, and protein aggregation is linked with matrix protein import. LONP1 also contributes to the degradation of imported, aberrant, unprocessed proteins using its protease activity. Taken together, our results show that LONP1 functions as a gatekeeper for specific proteins imported into the mitochondrial matrix.

SUBMITTER: Matsushima Y

PROVIDER: S-EPMC8368198 | biostudies-literature | 2021 Aug

REPOSITORIES: biostudies-literature

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Mitochondrial Lon protease is a gatekeeper for proteins newly imported into the matrix.

Matsushima Yuichi Y Takahashi Kazuya K Yue Song S Fujiyoshi Yuki Y Yoshioka Hideaki H Aihara Masamune M Setoyama Daiki D Uchiumi Takeshi T Fukuchi Satoshi S Kang Dongchon D

Communications biology 20210816 1

Human ATP-dependent Lon protease (LONP1) forms homohexameric, ring-shaped complexes. Depletion of LONP1 causes aggregation of a broad range of proteins in the mitochondrial matrix and decreases the levels of their soluble forms. The ATP hydrolysis activity, but not protease activity, of LONP1 is critical for its chaperone-like anti-aggregation activity. LONP1 forms a complex with the import machinery and an incoming protein, and protein aggregation is linked with matrix protein import. LONP1 als ...[more]

PMID: 34400774

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Lon protease: a novel mitochondrial matrix protein in the interconnection between drug-induced mitochondrial dysfunction and endoplasmic reticulum stress.

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