Summary for 6QC4
| Entry DOI | 10.2210/pdb6qc4/pdb |
| Related | 6q9b 6q9d 6q9e 6qa9 6qbx 6qc2 6qc3 |
| EMDB information | 4479 4480 4481 4482 4493 4494 4495 4496 |
| Descriptor | UQCRC1, Ubiquinol-cytochrome c reductase, complex III subunit X, NADH-ubiquinone oxidoreductase chain 3, ... (63 entities in total) |
| Functional Keywords | supercomplex, cellular respiration, mitochondria, electron transport |
| Biological source | Ovis aries More |
| Total number of polymer chains | 65 |
| Total formula weight | 1445953.26 |
| Authors | Letts, J.A.,Sazanov, L.A. (deposition date: 2018-12-26, release date: 2019-08-21, Last modification date: 2024-11-13) |
| Primary citation | Letts, J.A.,Fiedorczuk, K.,Degliesposti, G.,Skehel, M.,Sazanov, L.A. Structures of Respiratory Supercomplex I+III2Reveal Functional and Conformational Crosstalk. Mol.Cell, 75:1131-1146.e6, 2019 Cited by PubMed Abstract: The mitochondrial electron transport chain complexes are organized into supercomplexes (SCs) of defined stoichiometry, which have been proposed to regulate electron flux via substrate channeling. We demonstrate that CoQ trapping in the isolated SC I+III limits complex (C)I turnover, arguing against channeling. The SC structure, resolved at up to 3.8 Å in four distinct states, suggests that CoQ oxidation may be rate limiting because of unequal access of CoQ to the active sites of CIII. CI shows a transition between "closed" and "open" conformations, accompanied by the striking rotation of a key transmembrane helix. Furthermore, the state of CI affects the conformational flexibility within CIII, demonstrating crosstalk between the enzymes. CoQ was identified at only three of the four binding sites in CIII, suggesting that interaction with CI disrupts CIII symmetry in a functionally relevant manner. Together, these observations indicate a more nuanced functional role for the SCs. PubMed: 31492636DOI: 10.1016/j.molcel.2019.07.022 PDB entries with the same primary citation |
| Experimental method | ELECTRON MICROSCOPY (4.6 Å) |
Structure validation
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