2MAK

Solution structure of the STIM1 CC1-CC2 homodimer in complex with two Orai1 C-terminal domains.


Experimental Data Snapshot

  • Method: SOLUTION NMR
  • Conformers Calculated: 200 
  • Conformers Submitted: 20 
  • Selection Criteria: structures with the lowest energy 

wwPDB Validation 3D Report Full Report


This is version 1.0 of the entry. See complete history

Literature

STIM1/Orai1 coiled-coil interplay in the regulation of store-operated calcium entry.

Stathopulos, P.B.Schindl, R.Fahrner, M.Zheng, L.Gasmi-Seabrook, G.M.Muik, M.Romanin, C.Ikura, M.

(2013) Nat Commun 4: 2963-2963

  • DOI: 10.1038/ncomms3963
  • Primary Citation of Related Structures:  

  • PubMed Abstract: 
  • Orai1 calcium channels in the plasma membrane are activated by stromal interaction molecule-1 (STIM1), an endoplasmic reticulum calcium sensor, to mediate store-operated calcium entry (SOCE). The cytosolic region of STIM1 contains a long putative coi ...

    Orai1 calcium channels in the plasma membrane are activated by stromal interaction molecule-1 (STIM1), an endoplasmic reticulum calcium sensor, to mediate store-operated calcium entry (SOCE). The cytosolic region of STIM1 contains a long putative coiled-coil (CC)1 segment and shorter CC2 and CC3 domains. Here we present solution nuclear magnetic resonance structures of a trypsin-resistant CC1-CC2 fragment in the apo and Orai1-bound states. Each CC1-CC2 subunit forms a U-shaped structure that homodimerizes through antiparallel interactions between equivalent α-helices. The CC2:CC2' helix pair clamps two identical acidic Orai1 C-terminal helices at opposite ends of a hydrophobic/basic STIM-Orai association pocket. STIM1 mutants disrupting CC1:CC1' interactions attenuate, while variants promoting CC1 stability spontaneously activate Orai1 currents. CC2 mutations cause remarkable variability in Orai1 activation because of a dual function in binding Orai1 and autoinhibiting STIM1 oligomerization via interactions with CC3. We conclude that SOCE is activated through dynamic interplay between STIM1 and Orai1 helices.


    Organizational Affiliation

    University Health Network and Department of Medical Biophysics, Campbell Family Cancer Research Institute, Ontario Cancer Institute, University of Toronto, Room 4-804, MaRS TMDT, 101 College Street, Toronto, Ontario, Canada M5G 1L7.




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
Stromal interaction molecule 1
A, C
82Homo sapiensMutation(s): 0 
Gene Names: STIM1 (GOK)
Find proteins for Q13586 (Homo sapiens)
Go to Gene View: STIM1
Go to UniProtKB:  Q13586
Entity ID: 2
MoleculeChainsSequence LengthOrganismDetails
Calcium release-activated calcium channel protein 1
B, D
23Homo sapiensMutation(s): 0 
Gene Names: ORAI1 (CRACM1, TMEM142A)
Find proteins for Q96D31 (Homo sapiens)
Go to Gene View: ORAI1
Go to UniProtKB:  Q96D31
Experimental Data & Validation

Experimental Data

  • Method: SOLUTION NMR
  • Conformers Calculated: 200 
  • Conformers Submitted: 20 
  • Selection Criteria: structures with the lowest energy 

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History 

Deposition Data

Revision History 

  • Version 1.0: 2014-01-15
    Type: Initial release