5KUI

Human mitochondrial calcium uniporter (residues 72-189) crystal structure with calcium.


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.70 Å
  • R-Value Free: 0.299 
  • R-Value Work: 0.273 
  • R-Value Observed: 0.280 

wwPDB Validation   3D Report Full Report


This is version 1.3 of the entry. See complete history


Literature

Structural Insights into Mitochondrial Calcium Uniporter Regulation by Divalent Cations.

Lee, S.K.Shanmughapriya, S.Mok, M.C.Dong, Z.Tomar, D.Carvalho, E.Rajan, S.Junop, M.S.Madesh, M.Stathopulos, P.B.

(2016) Cell Chem Biol 23: 1157-1169

  • DOI: 10.1016/j.chembiol.2016.07.012
  • Primary Citation of Related Structures:  
    5KUE, 5KUG, 5KUI, 5KUJ

  • PubMed Abstract: 
  • Calcium (Ca(2+)) flux into the matrix is tightly controlled by the mitochondrial Ca(2+) uniporter (MCU) due to vital roles in cell death and bioenergetics. However, the precise atomic mechanisms of MCU regulation remain unclear. Here, we solved the crystal structure of the N-terminal matrix domain of human MCU, revealing a β-grasp-like fold with a cluster of negatively charged residues that interacts with divalent cations ...

    Calcium (Ca(2+)) flux into the matrix is tightly controlled by the mitochondrial Ca(2+) uniporter (MCU) due to vital roles in cell death and bioenergetics. However, the precise atomic mechanisms of MCU regulation remain unclear. Here, we solved the crystal structure of the N-terminal matrix domain of human MCU, revealing a β-grasp-like fold with a cluster of negatively charged residues that interacts with divalent cations. Binding of Ca(2+) or Mg(2+) destabilizes and shifts the self-association equilibrium of the domain toward monomer. Mutational disruption of the acidic face weakens oligomerization of the isolated matrix domain and full-length human protein similar to cation binding and markedly decreases MCU activity. Moreover, mitochondrial Mg(2+) loading or blockade of mitochondrial Ca(2+) extrusion suppresses MCU Ca(2+)-uptake rates. Collectively, our data reveal that the β-grasp-like matrix region harbors an MCU-regulating acidic patch that inhibits human MCU activity in response to Mg(2+) and Ca(2+) binding.


    Organizational Affiliation

    Department of Physiology and Pharmacology, Schulich School of Medicine and Dentistry, Western University, London, ON, Canada, N6A 5C1.



Macromolecules
Find similar proteins by:  (by identity cutoff)  |  3D Structure
Entity ID: 1
MoleculeChainsSequence LengthOrganismDetailsImage
Calcium uniporter protein, mitochondrialA124Homo sapiensMutation(s): 0 
Gene Names: MCUC10orf42CCDC109A
UniProt & NIH Common Fund Data Resources
Find proteins for Q8NE86 (Homo sapiens)
Explore Q8NE86 
Go to UniProtKB:  Q8NE86
PHAROS:  Q8NE86
Protein Feature View
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  • Reference Sequence
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.70 Å
  • R-Value Free: 0.299 
  • R-Value Work: 0.273 
  • R-Value Observed: 0.280 
  • Space Group: P 65
Unit Cell:
Length ( Å )Angle ( ˚ )
a = 51.28α = 90
b = 51.28β = 90
c = 71.71γ = 120
Software Package:
Software NamePurpose
iMOSFLMdata reduction
PHENIXphasing
PHENIXmodel building
PHENIXrefinement

Structure Validation

View Full Validation Report




Entry History & Funding Information

Deposition Data


Funding OrganizationLocationGrant Number
Natural Sciences and Engineering Research Council (NSERC, Canada)Canada05239

Revision History  (Full details and data files)

  • Version 1.0: 2016-09-07
    Type: Initial release
  • Version 1.1: 2016-10-05
    Changes: Database references
  • Version 1.2: 2017-09-20
    Changes: Author supporting evidence, Derived calculations
  • Version 1.3: 2020-01-08
    Changes: Author supporting evidence