Publications & Reports

Super-resolution microscopy reveals arrangement of inner membrane protein complexes in mammalian mitochondria.

Palmer CS, Lou J, Kouskousis B, Pandzic E, Anderson AJ, Kang Y, Hinde E, Stojanovski D
Department of Biochemistry and Pharmacology and The Bio21 Molecular Science and Biotechnology Institute, The University of Melbourne, Parkville, Victoria, 3010, Australia.

Abstract

The mitochondrial inner membrane is a protein rich environment containing large multimeric complexes including complexes of the mitochondrial electron transport chain, mitochondrial translocases and quality control machineries. Although the inner membrane is highly proteinaceous, with 40-60% of all mitochondrial proteins localised to this compartment, little is known about the spatial distribution and organisation of complexes in this environment. We set out to survey the arrangement of inner membrane complexes using stochastic optical reconstruction microscopy (STORM). We show subunits of the TIM23 Complex, Tim23 and Tim44, and the Complex IV subunit COXIV form organised clusters and show distinct properties to the outer membrane protein Tom20. Density based cluster analysis indicated a bimodal distribution of Tim44 that is distinct from Tim23, suggesting distinct TIM23 subcomplexes. COXIV is arranged in larger clusters, that are disrupted upon disruption of Complex IV assembly. Thus, STORM super-resolution microscopy is a powerful approach to examine the nanoscale distribution of mitochondrial inner membrane complexes, providing a “visual” approach to obtaining pivotal information on how mitochondrial complexes exist in a cellular context.

Link to publisher’s web site

Publication

  • Journal: Journal of Cell Science
  • Published: 11/06/2021
  • Volume: 134
  • Issue: 13
  • Pagination: jcs252197

Author