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Signal recognition initiates reorganization of the presequence translocase during protein import.

ABSTRACT: The mitochondrial presequence translocase interacts with presequence-containing precursors at the intermembrane space (IMS) side of the inner membrane to mediate their translocation into the matrix. Little is known as too how these matrix-targeting signals activate the translocase in order to initiate precursor transport. Therefore, we analysed how signal recognition by the presequence translocase initiates reorganization among Tim-proteins during import. Our analyses revealed that the presequence receptor Tim50 interacts with Tim21 in a signal-sensitive manner in a process that involves the IMS-domain of the Tim23 channel. The signal-driven release of Tim21 from Tim50 promotes recruitment of Pam17 and thus triggers formation of the motor-associated form of the TIM23 complex required for matrix transport.

SUBMITTER: Lytovchenko O

PROVIDER: S-EPMC3604718 | biostudies-literature | 2013 Mar

REPOSITORIES: biostudies-literature

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Signal recognition initiates reorganization of the presequence translocase during protein import.

Lytovchenko Oleksandr O Melin Jonathan J Schulz Christian C Kilisch Markus M Hutu Dana P DP Rehling Peter P

The EMBO journal 20130212 6

The mitochondrial presequence translocase interacts with presequence-containing precursors at the intermembrane space (IMS) side of the inner membrane to mediate their translocation into the matrix. Little is known as too how these matrix-targeting signals activate the translocase in order to initiate precursor transport. Therefore, we analysed how signal recognition by the presequence translocase initiates reorganization among Tim-proteins during import. Our analyses revealed that the presequen ...[more]

PMID: 23403928

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