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The mitochondrial TMEM177 associates with COX20 during COX2 biogenesis.

ABSTRACT: The three mitochondrial-encoded proteins, COX1, COX2, and COX3, form the core of the cytochrome c oxidase. Upon synthesis, COX2 engages with COX20 in the inner mitochondrial membrane, a scaffold protein that recruits metallochaperones for copper delivery to the CuA-Site of COX2. Here we identified the human protein, TMEM177 as a constituent of the COX20 interaction network. Loss or increase in the amount of TMEM177 affects COX20 abundance leading to reduced or increased COX20 levels respectively. TMEM177 associates with newly synthesized COX2 and SCO2 in a COX20-dependent manner. Our data shows that by unbalancing the amount of TMEM177, newly synthesized COX2 accumulates in a COX20-associated state. We conclude that TMEM177 promotes assembly of COX2 at the level of CuA-site formation.

SUBMITTER: Lorenzi I

PROVIDER: S-EPMC5764226 | biostudies-literature | 2018 Feb

REPOSITORIES: biostudies-literature

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The mitochondrial TMEM177 associates with COX20 during COX2 biogenesis.

Lorenzi Isotta I Oeljeklaus Silke S Aich Abhishek A Ronsör Christin C Callegari Sylvie S Dudek Jan J Warscheid Bettina B Dennerlein Sven S Rehling Peter P

Biochimica et biophysica acta. Molecular cell research 20171116 2

The three mitochondrial-encoded proteins, COX1, COX2, and COX3, form the core of the cytochrome c oxidase. Upon synthesis, COX2 engages with COX20 in the inner mitochondrial membrane, a scaffold protein that recruits metallochaperones for copper delivery to the Cu<sub>A</sub>-Site of COX2. Here we identified the human protein, TMEM177 as a constituent of the COX20 interaction network. Loss or increase in the amount of TMEM177 affects COX20 abundance leading to reduced or increased COX20 levels r ...[more]

PMID: 29154948

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Dataset Information

The mitochondrial TMEM177 associates with COX20 during COX2 biogenesis.

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The mitochondrial TMEM177 associates with COX20 during COX2 biogenesis.

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