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Pam17 and Tim44 act sequentially in protein import into the mitochondrial matrix.

ABSTRACT: Import of proteins into the matrix is driven by the Tim23 presequence translocase-associated import motor PAM. The core component of PAM is the mitochondrial chaperone mtHsp70, which ensures efficient translocation of proteins across the inner membrane through interactions with the J-protein complex Pam16-Pam18 (Tim16-Tim14) and its cochaperone Tim44. The recently identified non-essential Pam17 is a further member of PAM. Genetic and biochemical analyses reveal synthetic interactions between PAM17 and TIM44. Pam17 is involved in an early stage of protein translocation whereas Tim44 assists in a later step of transport, suggesting that both proteins can cooperate in a complementary manner in protein import.

SUBMITTER: Schiller D

PROVIDER: S-EPMC3353651 | biostudies-literature | 2009 Nov

REPOSITORIES: biostudies-literature

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Pam17 and Tim44 act sequentially in protein import into the mitochondrial matrix.

Schiller Dirk D

The international journal of biochemistry & cell biology 20090703 11

Import of proteins into the matrix is driven by the Tim23 presequence translocase-associated import motor PAM. The core component of PAM is the mitochondrial chaperone mtHsp70, which ensures efficient translocation of proteins across the inner membrane through interactions with the J-protein complex Pam16-Pam18 (Tim16-Tim14) and its cochaperone Tim44. The recently identified non-essential Pam17 is a further member of PAM. Genetic and biochemical analyses reveal synthetic interactions between PAM ...[more]

PMID: 19577659

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