Membrane depolarization activates the mitochondrial protease OMA1 by stimulating self-cleavage.
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ABSTRACT:
SUBMITTER: Zhang K
PROVIDER: S-EPMC4210089 | biostudies-other | 2014 May
REPOSITORIES: biostudies-other
Publications
Membrane depolarization activates the mitochondrial protease OMA1 by stimulating self-cleavage.
Zhang Kuan K Li Huihui H Song Zhiyin Z
EMBO reports 20140409 5
Mitochondrial inner membrane fusion depends on the dynamin-related GTPase OPA1 and the function of OPA1 is regulated by proteolytic cleavage. The mitochondrial proteases Yme1L and OMA1 cleave OPA1 at S2 and S1 sites, respectively. Here, we show that OMA1 is cleaved to a short form (S-OMA1) by itself upon mitochondrial membrane depolarization; S-OMA1 is degraded quickly but could be stabilized by CCCP treatment or Prohibitin knockdown in cells. In addition, OMA1 processing is positively correlate ...[more]
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