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Updated: Jun 21, 2026

Assessment of Submitochondrial Protein Localization in Budding Yeast Saccharomyces cerevisiae
Published on: July 19, 2021
Pam17 and Tim44 act sequentially in protein import into the mitochondrial matrix
1Department of Biochemistry, University of Wisconsin-Madison, Madison, WI 53706, USA. schiller@biochem.uni-frankfurt.de
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.
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