5E1J

Structure of voltage-gated two-pore channel TPC1 from Arabidopsis thaliana


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 3.308 Å
  • R-Value Free: 0.332 
  • R-Value Work: 0.325 

wwPDB Validation 3D Report Full Report


This is version 1.4 of the entry. See complete history

Literature

Structure of the voltage-gated two-pore channel TPC1 from Arabidopsis thaliana.

Guo, J.Zeng, W.Chen, Q.Lee, C.Chen, L.Yang, Y.Cang, C.Ren, D.Jiang, Y.

(2016) Nature 531: 196-201

  • DOI: 10.1038/nature16446

  • PubMed Abstract: 
  • Two-pore channels (TPCs) contain two copies of a Shaker-like six-transmembrane (6-TM) domain in each subunit and are ubiquitously expressed in both animals and plants as organellar cation channels. Here we present the crystal structure of a vacuolar ...

    Two-pore channels (TPCs) contain two copies of a Shaker-like six-transmembrane (6-TM) domain in each subunit and are ubiquitously expressed in both animals and plants as organellar cation channels. Here we present the crystal structure of a vacuolar two-pore channel from Arabidopsis thaliana, AtTPC1, which functions as a homodimer. AtTPC1 activation requires both voltage and cytosolic Ca(2+). Ca(2+) binding to the cytosolic EF-hand domain triggers conformational changes coupled to the pair of pore-lining inner helices from the first 6-TM domains, whereas membrane potential only activates the second voltage-sensing domain, the conformational changes of which are coupled to the pair of inner helices from the second 6-TM domains. Luminal Ca(2+) or Ba(2+) can modulate voltage activation by stabilizing the second voltage-sensing domain in the resting state and shift voltage activation towards more positive potentials. Our Ba(2+)-bound AtTPC1 structure reveals a voltage sensor in the resting state, providing hitherto unseen structural insight into the general voltage-gating mechanism among voltage-gated channels.


    Organizational Affiliation

    Department of Physiology, University of Texas Southwestern Medical Center, Dallas, Texas 75390-9040, USA.




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
Two pore calcium channel protein 1
A
741Arabidopsis thalianaMutation(s): 0 
Gene Names: TPC1 (CCH1, FOU2)
Membrane protein
mpstruct
Group: 
TRANSMEMBRANE PROTEINS: ALPHA-HELICAL
Sub Group: 
Channels: Potassium, Sodium, & Proton Ion-Selective
Protein: 
Two-pore channel TPC1
Find proteins for Q94KI8 (Arabidopsis thaliana)
Go to UniProtKB:  Q94KI8
Small Molecules
Ligands 2 Unique
IDChainsName / Formula / InChI Key2D Diagram3D Interactions
CA
Query on CA

Download SDF File 
Download CCD File 
A
CALCIUM ION
Ca
BHPQYMZQTOCNFJ-UHFFFAOYSA-N
 Ligand Interaction
BA
Query on BA

Download SDF File 
Download CCD File 
A
BARIUM ION
Ba
XDFCIPNJCBUZJN-UHFFFAOYSA-N
 Ligand Interaction
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 3.308 Å
  • R-Value Free: 0.332 
  • R-Value Work: 0.325 
  • Space Group: C 2 2 21
Unit Cell:
Length (Å)Angle (°)
a = 88.430α = 90.00
b = 158.850β = 90.00
c = 217.240γ = 90.00
Software Package:
Software NamePurpose
HKL-2000data scaling
SHARPphasing
PHENIXrefinement

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History & Funding Information

Deposition Data


Funding OrganizationLocationGrant Number
Howard Hughes Medical InstituteUnited States--
National Institutes of Health/National Institute of General Medical SciencesUnited StatesGM079179
Welch FoundationUnited StatesI-1578

Revision History 

  • Version 1.0: 2015-12-16
    Type: Initial release
  • Version 1.1: 2016-01-06
    Type: Database references
  • Version 1.2: 2016-03-23
    Type: Database references
  • Version 1.3: 2017-09-06
    Type: Author supporting evidence, Database references, Derived calculations
  • Version 1.4: 2017-11-22
    Type: Refinement description