6XQN

Structure of a mitochondrial calcium uniporter holocomplex (MICU1, MICU2, MCU, EMRE) in low Ca2+


Experimental Data Snapshot

  • Method: ELECTRON MICROSCOPY
  • Resolution: 3.30 Å
  • Aggregation State: PARTICLE 
  • Reconstruction Method: SINGLE PARTICLE 

wwPDB Validation   3D Report Full Report


This is version 1.3 of the entry. See complete history


Literature

Structures reveal gatekeeping of the mitochondrial Ca 2+ uniporter by MICU1-MICU2.

Wang, C.Jacewicz, A.Delgado, B.D.Baradaran, R.Long, S.B.

(2020) Elife 9

  • DOI: https://doi.org/10.7554/eLife.59991
  • Primary Citation of Related Structures:  
    6XQN, 6XQO

  • PubMed Abstract: 

    The mitochondrial calcium uniporter is a Ca 2+ -gated ion channel complex that controls mitochondrial Ca 2+ entry and regulates cell metabolism. MCU and EMRE form the channel while Ca 2+ -dependent regulation is conferred by MICU1 and MICU2 through an enigmatic process. We present a cryo-EM structure of an MCU-EMRE-MICU1-MICU2 holocomplex comprising MCU and EMRE subunits from the beetle Tribolium castaneum in complex with a human MICU1-MICU2 heterodimer at 3.3 Å resolution. With analogy to how neuronal channels are blocked by protein toxins, a uniporter interaction domain on MICU1 binds to a channel receptor site comprising MCU and EMRE subunits to inhibit ion flow under resting Ca 2+ conditions. A Ca 2+ -bound structure of MICU1-MICU2 at 3.1 Å resolution indicates how Ca 2+ -dependent changes enable dynamic response to cytosolic Ca 2+ signals.


  • Organizational Affiliation

    Structural Biology Program, Memorial Sloan Kettering Cancer Center, New York, United States.


Macromolecules
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Entity ID: 1
MoleculeChains Sequence LengthOrganismDetailsImage
Protein EMRE homolog, mitochondrial-like ProteinA [auth E],
D [auth G],
F [auth H]
70Tribolium castaneumMutation(s): 0 
Gene Names: TcasGA2_TC012057
Membrane Entity: Yes 
UniProt
Find proteins for D6X268 (Tribolium castaneum)
Explore D6X268 
Go to UniProtKB:  D6X268
Entity Groups  
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UniProt GroupD6X268
Sequence Annotations
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  • Reference Sequence
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Entity ID: 2
MoleculeChains Sequence LengthOrganismDetailsImage
Calcium uniporter proteinB [auth A],
C [auth B],
E [auth C],
G [auth D]
203Tribolium castaneumMutation(s): 0 
Gene Names: TcasGA2_TC013837
Membrane Entity: Yes 
UniProt
Find proteins for D6WIX5 (Tribolium castaneum)
Explore D6WIX5 
Go to UniProtKB:  D6WIX5
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UniProt GroupD6WIX5
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  • Reference Sequence
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Entity ID: 3
MoleculeChains Sequence LengthOrganismDetailsImage
Calcium uptake protein 1, mitochondrialH [auth I]394Homo sapiensMutation(s): 0 
Gene Names: MICU1CALCCBARA1
Membrane Entity: Yes 
UniProt & NIH Common Fund Data Resources
Find proteins for Q9BPX6 (Homo sapiens)
Explore Q9BPX6 
Go to UniProtKB:  Q9BPX6
GTEx:  ENSG00000107745 
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UniProt GroupQ9BPX6
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Entity ID: 4
MoleculeChains Sequence LengthOrganismDetailsImage
Calcium uptake protein 2, mitochondrialI [auth J]383Homo sapiensMutation(s): 0 
Gene Names: MICU2EFHA1
Membrane Entity: Yes 
UniProt & NIH Common Fund Data Resources
Find proteins for Q8IYU8 (Homo sapiens)
Explore Q8IYU8 
Go to UniProtKB:  Q8IYU8
PHAROS:  Q8IYU8
GTEx:  ENSG00000165487 
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UniProt GroupQ8IYU8
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  • Reference Sequence
Small Molecules
Ligands 1 Unique
IDChains Name / Formula / InChI Key2D Diagram3D Interactions
CA
Query on CA

Download Ideal Coordinates CCD File 
J [auth B]CALCIUM ION
Ca
BHPQYMZQTOCNFJ-UHFFFAOYSA-N
Experimental Data & Validation

Experimental Data

  • Method: ELECTRON MICROSCOPY
  • Resolution: 3.30 Å
  • Aggregation State: PARTICLE 
  • Reconstruction Method: SINGLE PARTICLE 
EM Software:
TaskSoftware PackageVersion
RECONSTRUCTIONRELION3.0
MODEL REFINEMENTPHENIX1.17.1-3660

Structure Validation

View Full Validation Report



Entry History & Funding Information

Deposition Data


Funding OrganizationLocationGrant Number
National Institutes of Health/National Institute of General Medical Sciences (NIH/NIGMS)United StatesR35GM131921
National Institutes of Health/National Cancer Institute (NIH/NCI)United StatesP30CA008748

Revision History  (Full details and data files)

  • Version 1.0: 2020-07-29
    Type: Initial release
  • Version 1.1: 2020-08-05
    Changes: Database references
  • Version 1.2: 2020-09-30
    Changes: Database references
  • Version 1.3: 2024-03-06
    Changes: Data collection, Database references