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TIM29 is a subunit of the human carrier translocase required for protein transport.

ABSTRACT: Hydrophobic inner mitochondrial membrane proteins with internal targeting signals, such as the metabolite carriers, use the carrier translocase (TIM22 complex) for transport into the inner membrane. Defects in this transport pathway have been associated with neurodegenerative disorders. While the TIM22 complex is well studied in baker's yeast, very little is known about the mammalian TIM22 complex. Using immunoprecipitation, we purified the human carrier translocase and identified a mitochondrial inner membrane protein TIM29 as a novel component, specific to metazoa. We show that TIM29 is a constituent of the 440 kDa TIM22 complex and interacts with oxidized TIM22. Our analyses demonstrate that TIM29 is required for the structural integrity of the TIM22 complex and for import of substrate proteins by the carrier translocase.

SUBMITTER: Callegari S

PROVIDER: S-EPMC5215392 | biostudies-literature | 2016 Dec

REPOSITORIES: biostudies-literature

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TIM29 is a subunit of the human carrier translocase required for protein transport.

Callegari Sylvie S Richter Frank F Chojnacka Katarzyna K Jans Daniel C DC Lorenzi Isotta I Pacheu-Grau David D Jakobs Stefan S Lenz Christof C Urlaub Henning H Dudek Jan J Chacinska Agnieszka A Rehling Peter P

FEBS letters 20161026 23

Hydrophobic inner mitochondrial membrane proteins with internal targeting signals, such as the metabolite carriers, use the carrier translocase (TIM22 complex) for transport into the inner membrane. Defects in this transport pathway have been associated with neurodegenerative disorders. While the TIM22 complex is well studied in baker's yeast, very little is known about the mammalian TIM22 complex. Using immunoprecipitation, we purified the human carrier translocase and identified a mitochondria ...[more]

PMID: 27718247

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