Cell Rep. 2024 Feb 21. pii: S2211-1247(24)00100-1. [Epub ahead of print]43(3): 113772
Patrick Horten,
Kuo Song,
Joshua Garlich,
Robert Hardt,
Lilia Colina-Tenorio,
Susanne E Horvath,
Uwe Schulte,
Bernd Fakler,
Martin van der Laan,
Thomas Becker,
Rosemary A Stuart,
Nikolaus Pfanner,
Heike Rampelt.
The mitochondrial inner membrane plays central roles in bioenergetics and metabolism and contains several established membrane protein complexes. Here, we report the identification of a mega-complex of the inner membrane, termed mitochondrial multifunctional assembly (MIMAS). Its large size of 3 MDa explains why MIMAS has escaped detection in the analysis of mitochondria so far. MIMAS combines proteins of diverse functions from respiratory chain assembly to metabolite transport, dehydrogenases, and lipid biosynthesis but not the large established supercomplexes of the respiratory chain, ATP synthase, or prohibitin scaffold. MIMAS integrity depends on the non-bilayer phospholipid phosphatidylethanolamine, in contrast to respiratory supercomplexes whose stability depends on cardiolipin. Our findings suggest that MIMAS forms a protein-lipid mega-assembly in the mitochondrial inner membrane that integrates respiratory biogenesis and metabolic processes in a multifunctional platform.
Keywords: CP: Metabolism; CP: Molecular biology; membrane protein complex; metabolism; metabolite carriers; mitochondria; phosphatidylethanolamine; phospholipids; protein assembly; respiratory chain