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Open data
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Basic information
Entry | Database: EMDB / ID: EMD-12706 | |||||||||
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Title | Murine CIII2 focus-refined from supercomplex CICIII2 | |||||||||
![]() | murine CIII2 focus-refined from CICIII2 | |||||||||
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Function / homology | ![]() subthalamus development / pons development / Respiratory electron transport / cerebellar Purkinje cell layer development / pyramidal neuron development / response to mercury ion / mitochondrial respiratory chain complex III assembly / thalamus development / response to cobalamin / Mitochondrial protein degradation ...subthalamus development / pons development / Respiratory electron transport / cerebellar Purkinje cell layer development / pyramidal neuron development / response to mercury ion / mitochondrial respiratory chain complex III assembly / thalamus development / response to cobalamin / Mitochondrial protein degradation / : / : / response to alkaloid / quinol-cytochrome-c reductase / response to copper ion / response to glucagon / cellular respiration / ubiquinol-cytochrome-c reductase activity / midbrain development / hypothalamus development / mitochondrial electron transport, ubiquinol to cytochrome c / response to hyperoxia / animal organ regeneration / electron transport coupled proton transport / response to cadmium ion / respiratory electron transport chain / response to hormone / response to activity / hippocampus development / response to calcium ion / mitochondrial membrane / response to toxic substance / metalloendopeptidase activity / 2 iron, 2 sulfur cluster binding / myelin sheath / response to ethanol / oxidoreductase activity / response to hypoxia / mitochondrial inner membrane / response to xenobiotic stimulus / ubiquitin protein ligase binding / heme binding / protein-containing complex binding / protein-containing complex / mitochondrion / proteolysis / nucleoplasm / membrane / metal ion binding Similarity search - Function | |||||||||
Biological species | ![]() ![]() ![]() ![]() | |||||||||
Method | single particle reconstruction / cryo EM / Resolution: 2.6 Å | |||||||||
![]() | Vercellino I / Sazanov LA | |||||||||
Funding support | ![]()
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![]() | ![]() Title: Structure and assembly of the mammalian mitochondrial supercomplex CIIICIV. Authors: Irene Vercellino / Leonid A Sazanov / ![]() Abstract: The enzymes of the mitochondrial electron transport chain are key players of cell metabolism. Despite being active when isolated, in vivo they associate into supercomplexes, whose precise role is ...The enzymes of the mitochondrial electron transport chain are key players of cell metabolism. Despite being active when isolated, in vivo they associate into supercomplexes, whose precise role is debated. Supercomplexes CIIICIV (refs. ), CICIII (ref. ) and CICIIICIV (respirasome) exist in mammals, but in contrast to CICIII and the respirasome, to date the only known eukaryotic structures of CIIICIV come from Saccharomyces cerevisiae and plants, which have different organization. Here we present the first, to our knowledge, structures of mammalian (mouse and ovine) CIIICIV and its assembly intermediates, in different conformations. We describe the assembly of CIIICIV from the CIII precursor to the final CIIICIV conformation, driven by the insertion of the N terminus of the assembly factor SCAF1 (ref. ) deep into CIII, while its C terminus is integrated into CIV. Our structures (which include CICIII and the respirasome) also confirm that SCAF1 is exclusively required for the assembly of CIIICIV and has no role in the assembly of the respirasome. We show that CIII is asymmetric due to the presence of only one copy of subunit 9, which straddles both monomers and prevents the attachment of a second copy of SCAF1 to CIII, explaining the presence of one copy of CIV in CIIICIV in mammals. Finally, we show that CIII and CIV gain catalytic advantage when assembled into the supercomplex and propose a role for CIIICIV in fine tuning the efficiency of electron transfer in the electron transport chain. | |||||||||
History |
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Structure visualization
Movie |
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Structure viewer | EM map: ![]() ![]() ![]() |
Supplemental images |
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Downloads & links
-EMDB archive
Map data | ![]() | 71.6 MB | ![]() | |
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Header (meta data) | ![]() ![]() | 28.4 KB 28.4 KB | Display Display | ![]() |
FSC (resolution estimation) | ![]() | 18.6 KB | Display | ![]() |
Images | ![]() | 156.1 KB | ||
Archive directory | ![]() ![]() | HTTPS FTP |
-Related structure data
Related structure data | ![]() 7o3hMC ![]() 7o37C ![]() 7o3cC ![]() 7o3eC M: atomic model generated by this map C: citing same article ( |
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Similar structure data |
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Links
EMDB pages | ![]() ![]() |
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Related items in Molecule of the Month |
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Map
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Annotation | murine CIII2 focus-refined from CICIII2 | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
Voxel size | X=Y=Z: 0.49981 Å | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
Density |
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Symmetry | Space group: 1 | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
Details | EMDB XML:
CCP4 map header:
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-Supplemental data
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Sample components
+Entire : Murine complex CIII2 focus-refined from supercomplex CICIII2
+Supramolecule #1: Murine complex CIII2 focus-refined from supercomplex CICIII2
+Macromolecule #1: Cytochrome b-c1 complex subunit 1, mitochondrial
+Macromolecule #2: Cytochrome b-c1 complex subunit 2, mitochondrial
+Macromolecule #3: Cytochrome b
+Macromolecule #4: Cytochrome c1, heme protein, mitochondrial
+Macromolecule #5: Cytochrome b-c1 complex subunit Rieske, mitochondrial
+Macromolecule #6: Cytochrome b-c1 complex subunit 7
+Macromolecule #7: Cytochrome b-c1 complex subunit 8
+Macromolecule #8: Cytochrome b-c1 complex subunit 6, mitochondrial
+Macromolecule #9: Cytochrome b-c1 complex subunit 9
+Macromolecule #10: Cytochrome b-c1 complex subunit 10
+Macromolecule #11: Cytochrome b-c1 complex subunit 9
+Macromolecule #12: 1,2-Distearoyl-sn-glycerophosphoethanolamine
+Macromolecule #13: CARDIOLIPIN
+Macromolecule #14: PROTOPORPHYRIN IX CONTAINING FE
+Macromolecule #15: HEME C
+Macromolecule #16: FE2/S2 (INORGANIC) CLUSTER
+Macromolecule #17: 1,2-DIACYL-SN-GLYCERO-3-PHOSPHOCHOLINE
-Experimental details
-Structure determination
Method | cryo EM |
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![]() | single particle reconstruction |
Aggregation state | particle |
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Sample preparation
Concentration | 4 mg/mL | |||||||||||||||
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Buffer | pH: 7.7 Component:
Details: CHAPS was added only upon freezing | |||||||||||||||
Grid | Model: Quantifoil R0.6/1 / Material: COPPER / Mesh: 300 / Support film - Material: CARBON / Support film - topology: CONTINUOUS / Support film - Film thickness: 1.0 nm / Pretreatment - Type: GLOW DISCHARGE | |||||||||||||||
Vitrification | Cryogen name: ETHANE / Chamber humidity: 100 % / Chamber temperature: 277 K / Instrument: FEI VITROBOT MARK IV |
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Electron microscopy
Microscope | FEI TITAN KRIOS |
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Image recording | Film or detector model: FEI FALCON III (4k x 4k) / Detector mode: INTEGRATING / Number grids imaged: 1 / Number real images: 7245 / Average exposure time: 1.17 sec. / Average electron dose: 90.66 e/Å2 |
Electron beam | Acceleration voltage: 300 kV / Electron source: ![]() |
Electron optics | C2 aperture diameter: 50.0 µm / Calibrated defocus max: 2.7 µm / Calibrated defocus min: 0.2 µm / Illumination mode: FLOOD BEAM / Imaging mode: BRIGHT FIELD / Cs: 2.7 mm / Nominal defocus max: 1.6 µm / Nominal defocus min: 0.4 µm / Nominal magnification: 75000 |
Sample stage | Specimen holder model: FEI TITAN KRIOS AUTOGRID HOLDER / Cooling holder cryogen: NITROGEN |
Experimental equipment | ![]() Model: Titan Krios / Image courtesy: FEI Company |