Biological Assembly 1  

 3D View: Structure | Ligand Interaction

Global Symmetry: Cyclic - C2  (3D View)
Global Stoichiometry: Hetero 20-mer - A8B8C2D2 Pseudo Symmetry: Asymmetric - C1 
Pseudo Stoichiometry: Hetero 20-mer - A8B4C3D2E2F1 

Biological assembly 1 assigned by authors.

Biological Assembly Evidence: gel filtration

Macromolecule Content

• Total Structure Weight: 453.38 kDa 
• Atom Count: 29867 
• Residue Count: 3645 
• Unique protein chains: 5

6WDO

Cryo-EM structure of mitochondrial calcium uniporter holocomplex in high Ca2+

• DOI: 10.2210/pdb6WDO/pdb
• EMDataResource: EMD-21643

• Classification: MEMBRANE PROTEIN
• Organism(s): Homo sapiens
• Expression System: Homo sapiens
• Mutation(s): No 


• Deposited: 2020-04-01 Released: 2020-05-27 
• Deposition Author(s): Feng, L., Zhang, J., Fan, M.

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Experimental Data Snapshot

• Method: ELECTRON MICROSCOPY
• Resolution: 3.60 Å
• Aggregation State: PARTICLE 
• Reconstruction Method: SINGLE PARTICLE 

Literature

Structure and mechanism of the mitochondrial Ca2+uniporter holocomplex.

Fan, M., Zhang, J., Tsai, C.W., Orlando, B.J., Rodriguez, M., Xu, Y., Liao, M., Tsai, M.F., Feng, L.

(2020) Nature 582: 129-133

• PubMed: 32494073 
• DOI: 10.1038/s41586-020-2309-6
• Primary Citation of Related Structures:  
  6WDN, 6WDO


• PubMed Abstract: 
  

Mitochondria take up Ca ²⁺ through the mitochondrial calcium uniporter complex to regulate energy production, cytosolic Ca ²⁺ signalling and cell death ^1,2 . In mammals, the uniporter complex (uniplex) contains four core components: the pore-forming MCU protein, the gatekeepers MICU1 and MICU2, and an auxiliary subunit, EMRE, essential for Ca ²⁺ transport ^3-8 . To prevent detrimental Ca ²⁺ overload, the activity of MCU must be tightly regulated by MICUs, which sense changes in cytosolic Ca ²⁺ concentrations to switch MCU on and off ^9,10 . Here we report cryo-electron microscopic structures of the human mitochondrial calcium uniporter holocomplex in inhibited and Ca ²⁺ -activated states. These structures define the architecture of this multicomponent Ca ²⁺ -uptake machinery and reveal the gating mechanism by which MICUs control uniporter activity. Our work provides a framework for understanding regulated Ca ²⁺ uptake in mitochondria, and could suggest ways of modulating uniporter activity to treat diseases related to mitochondrial Ca ²⁺ overload.

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Organizational Affiliation: 

Department of Molecular and Cellular Physiology, Stanford University School of Medicine, Stanford, CA, USA. [e-mail].

Macromolecules

Entity ID: 1
Molecule	Chains	Sequence Length	Organism	Details	Image
Calcium uniporter protein, mitochondrial	A, E, G, I, M, O	273	Homo sapiens	Mutation(s): 0  Gene Names: MCU, C10orf42, CCDC109A
Membrane protein Mpstruc	Group:  TRANSMEMBRANE PROTEINS: ALPHA-HELICAL		Sub Group:  Channels: Calcium Ion-Selective	Protein:  mitochondrial calcium uniporter holocomplex, low Ca2+
Find proteins for Q8NE86 (Homo sapiens) Explore Q8NE86  Go to UniProtKB:  Q8NE86
NIH Common Fund Data Resources
PHAROS  Q8NE86 GTEx  ENSG00000156026

Entity ID: 2
Molecule	Chains	Sequence Length	Organism	Details	Image
Essential MCU regulator, mitochondrial	B, D, F, H, J, L, N, P	53	Homo sapiens	Mutation(s): 0  Gene Names: SMDT1, C22orf32, EMRE
Membrane protein Mpstruc	Group:  TRANSMEMBRANE PROTEINS: ALPHA-HELICAL		Sub Group:  Channels: Calcium Ion-Selective	Protein:  mitochondrial calcium uniporter holocomplex, low Ca2+
Find proteins for Q9H4I9 (Homo sapiens) Explore Q9H4I9  Go to UniProtKB:  Q9H4I9
NIH Common Fund Data Resources
PHAROS  Q9H4I9 GTEx  ENSG00000183172

Entity ID: 3
Molecule	Chains	Sequence Length	Organism	Details	Image
Calcium uniporter protein, mitochondrial	C, K	268	Homo sapiens	Mutation(s): 0  Gene Names: MCU, C10orf42, CCDC109A
Membrane protein Mpstruc	Group:  TRANSMEMBRANE PROTEINS: ALPHA-HELICAL		Sub Group:  Channels: Calcium Ion-Selective	Protein:  mitochondrial calcium uniporter holocomplex, low Ca2+
Find proteins for Q8NE86 (Homo sapiens) Explore Q8NE86  Go to UniProtKB:  Q8NE86
NIH Common Fund Data Resources
PHAROS  Q8NE86 GTEx  ENSG00000156026

Entity ID: 4
Molecule	Chains	Sequence Length	Organism	Details	Image
Calcium uptake protein 1, mitochondrial	Q, S	339	Homo sapiens	Mutation(s): 0  Gene Names: MICU1, CALC, CBARA1
Membrane protein Mpstruc	Group:  TRANSMEMBRANE PROTEINS: ALPHA-HELICAL		Sub Group:  Channels: Calcium Ion-Selective	Protein:  mitochondrial calcium uniporter holocomplex, low Ca2+
Find proteins for Q9BPX6 (Homo sapiens) Explore Q9BPX6  Go to UniProtKB:  Q9BPX6
NIH Common Fund Data Resources
PHAROS  Q9BPX6 GTEx  ENSG00000107745

Entity ID: 5
Molecule	Chains	Sequence Length	Organism	Details	Image
Calcium uptake protein 2, mitochondrial	R, T	310	Homo sapiens	Mutation(s): 0  Gene Names: MICU2, EFHA1
Membrane protein Mpstruc	Group:  TRANSMEMBRANE PROTEINS: ALPHA-HELICAL		Sub Group:  Channels: Calcium Ion-Selective	Protein:  mitochondrial calcium uniporter holocomplex, low Ca2+
Find proteins for Q8IYU8 (Homo sapiens) Explore Q8IYU8  Go to UniProtKB:  Q8IYU8
NIH Common Fund Data Resources
PHAROS  Q8IYU8 GTEx  ENSG00000165487

Small Molecules

Ligands 1 Unique
ID	Chains	Name / Formula / InChI Key	2D Diagram
CA	A, I	CALCIUM ION Ca BHPQYMZQTOCNFJ-UHFFFAOYSA-N

Experimental Data & Validation

Experimental Data

• Method: ELECTRON MICROSCOPY
• Resolution: 3.60 Å
• Aggregation State: PARTICLE 
• Reconstruction Method: SINGLE PARTICLE 

Structure Validation

Entry History 

Deposition Data

• Deposited Date: 2020-04-01 
• Released Date: 2020-05-27 
Deposition Author(s): Feng, L., Zhang, J., Fan, M.

Revision History 

• Version 1.0: 2020-05-27
  Type: Initial release
  
• Version 1.1: 2020-06-17
  Changes: Database references