Molecular basis of the dynamic structure of the TIM23 complex in the mitochondrial intermembrane space

Rakhi Bajaj, Lukasz Jaremko, Mariusz Jaremko, Stefan Becker, Markus Zweckstetter*

*Corresponding author for this work

Research output: Contribution to journalArticlepeer-review

20 Scopus citations


The presequence translocase TIM23 is a highly dynamic complex in which its subunits can adopt multiple conformations and undergo association-dissociation to facilitate import of proteins into mitochondria. Despite the importance of protein-protein interactions in TIM23, little is known about the molecular details of these processes. Using nuclear magnetic resonance spectroscopy, we characterized the dynamic interaction network of the intermembrane space domains of Tim23, Tim21, Tim50, and Tom22 at single-residue level. We show that Tim23IMS contains multiple sites to efficiently interact with the intermembrane space domain of Tim21 and to bind to Tim21, Tim50, and Tom22. In addition, we reveal the atomic details of the dynamic Tim23IMS-Tim21IMS complex. The combined data support a central role of the intermembrane space domain of Tim23 in the formation and regulation of the presequence translocase.

Original languageEnglish (US)
Pages (from-to)1501-1511
Number of pages11
Issue number10
StatePublished - Oct 7 2014

ASJC Scopus subject areas

  • Molecular Biology
  • Structural Biology
  • Medicine(all)

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