Biological Assembly 1  

 3D View: Structure | Ligand Interaction

Global Symmetry: Cyclic - C4  (3D View)
Global Stoichiometry: Homo 4-mer - A4 

Biological assembly 1 assigned by authors.

Biological Assembly Evidence: cross-linking

Macromolecule Content

• Total Structure Weight: 164.55 kDa 
• Atom Count: 7251 
• Residue Count: 900 
• Unique protein chains: 1

6DNF

Cryo-EM structure of the mitochondrial calcium uniporter MCU from the fungus Cyphellophora europaea

• DOI: 10.2210/pdb6DNF/pdb
• EMDataResource: EMD-7971

• Classification: MEMBRANE PROTEIN
• Organism(s): Cyphellophora europaea CBS 101466
• Expression System: Komagataella pastoris
• Mutation(s): No 


• Deposited: 2018-06-06 Released: 2018-07-11 
• Deposition Author(s): Long, S.B., Baradaran, R., Wang, C.
• Funding Organization(s): National Institutes of Health/National Institute of General Medical Sciences (NIH/NIGMS)

---

Experimental Data Snapshot

• Method: ELECTRON MICROSCOPY
• Resolution: 3.20 Å
• Aggregation State: PARTICLE 
• Reconstruction Method: SINGLE PARTICLE 

Literature

Cryo-EM structures of fungal and metazoan mitochondrial calcium uniporters.

Baradaran, R., Wang, C., Siliciano, A.F., Long, S.B.

(2018) Nature 559: 580-584

• PubMed: 29995857 
• DOI: 10.1038/s41586-018-0331-8
• Primary Citation of Related Structures:  
  6DNF


• PubMed Abstract: 
  

The mitochondrial calcium uniporter (MCU) is a highly selective calcium channel and a major route of calcium entry into mitochondria. How the channel catalyses ion permeation and achieves ion selectivity are not well understood, partly because MCU is thought to have a distinct architecture in comparison to other cellular channels. Here we report cryo-electron microscopy reconstructions of MCU channels from zebrafish and Cyphellophora europaea at 8.5 Å and 3.2 Å resolutions, respectively. In contrast to a previous report of pentameric stoichiometry for MCU, both channels are tetramers. The atomic model of C. europaea MCU shows that a conserved WDXXEP signature sequence forms the selectivity filter, in which calcium ions are arranged in single file. Coiled-coil legs connect the pore to N-terminal domains in the mitochondrial matrix. In C. europaea MCU, the N-terminal domains assemble as a dimer of dimers; in zebrafish MCU, they form an asymmetric crescent. The structures define principles that underlie ion permeation and calcium selectivity in this unusual channel.

---

Organizational Affiliation: 

Structural Biology Program, Memorial Sloan Kettering Cancer Center, New York, NY, USA. [e-mail].

Macromolecules

Entity ID: 1
Molecule	Chains	Sequence Length	Organism	Details	Image
Mitochondrial calcium uniporter MCU	A, B, C, D	352	Cyphellophora europaea CBS 101466	Mutation(s): 0  Gene Names: HMPREF1541_00236
Find proteins for W2SDE2 (Cyphellophora europaea CBS 101466) Explore W2SDE2  Go to UniProtKB:  W2SDE2

Small Molecules

Ligands 2 Unique
ID	Chains	Name / Formula / InChI Key	2D Diagram
DGG	A, B, C, D	1-[GLYCEROLYLPHOSPHONYL]-2-[8-(2-HEXYL-CYCLOPROPYL)-OCTANAL-1-YL]-3-[HEXADECANAL-1-YL]-GLYCEROL C39 H75 O10 P JWIOKCJPLNKYBQ-JIZALCTLSA-N
CA	A, B	CALCIUM ION Ca BHPQYMZQTOCNFJ-UHFFFAOYSA-N

Experimental Data & Validation

Experimental Data

• Method: ELECTRON MICROSCOPY
• Resolution: 3.20 Å
• Aggregation State: PARTICLE 
• Reconstruction Method: SINGLE PARTICLE 

Structure Validation

Entry History & Funding Information

Deposition Data

• Deposited Date: 2018-06-06 
• Released Date: 2018-07-11 
Deposition Author(s): Long, S.B., Baradaran, R., Wang, C.

---

Funding Organization	Location	Grant Number
National Institutes of Health/National Institute of General Medical Sciences (NIH/NIGMS)	United States	R01GM094273

Revision History 

• Version 1.0: 2018-07-11
  Type: Initial release
  
• Version 1.1: 2018-07-25
  Changes: Data collection, Database references
• Version 1.2: 2018-08-08
  Changes: Data collection, Database references
• Version 1.3: 2020-01-08
  Changes: Author supporting evidence