8GZU

Cryo-EM structure of Tetrahymena thermophila respiratory Megacomplex MC (IV2+I+III2+II)2

This is a non-PDB format compatible entry.

Summary for 8GZU

• Entry DOI: 10.2210/pdb8gzu/pdb
• EMDB information: 34403 34404 34405
• Descriptor: Transmembrane protein, putative, COXTT10, Ymf65, ... (164 entities in total)
• Functional Keywords: electron transport chain, supercomplex, membrane protein, tetrahymena thermophila, electron transport
• Biological source: Tetrahymena thermophila SB210; More
• Total number of polymer chains: 436
• Total formula weight: 11803642.70

Authors

Wu, M.C.,Hu, Y.Q.,Han, F.Z.,Zhou, L. (deposition date: 2022-09-27, release date: 2023-06-14, Last modification date: 2024-10-16)

Primary citation

Han, F.,Hu, Y.,Wu, M.,He, Z.,Tian, H.,Zhou, L.
Structures of Tetrahymena thermophila respiratory megacomplexes on the tubular mitochondrial cristae.
Nat Commun, 14:2542-2542, 2023

PubMed Abstract: Tetrahymena thermophila, a classic ciliate model organism, has been shown to possess tubular mitochondrial cristae and highly divergent electron transport chain involving four transmembrane protein complexes (I-IV). Here we report cryo-EM structures of its ~8 MDa megacomplex IV+ (I + III+ II), as well as a ~ 10.6 MDa megacomplex (IV + I + III+ II) at lower resolution. In megacomplex IV+ (I + III+ II), each CIV protomer associates one copy of supercomplex I + III and one copy of CII, forming a half ring-shaped architecture that adapts to the membrane curvature of mitochondrial cristae. Megacomplex (IV+ I + III+ II) defines the relative position between neighbouring half rings and maintains the proximity between CIV and CIII cytochrome c binding sites. Our findings expand the current understanding of divergence in eukaryotic electron transport chain organization and how it is related to mitochondrial morphology.

PubMed: 37248254
DOI: 10.1038/s41467-023-38158-5

Experimental method

ELECTRON MICROSCOPY (4.18 Å)