4UMO

Crystal Structure of the Kv7.1 proximal C-terminal Domain in Complex with Calmodulin


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 3 Å
  • R-Value Free: 0.247 
  • R-Value Work: 0.213 

wwPDB Validation 3D Report Full Report


This is version 1.1 of the entry. See complete history

Literature

Structural Basis of a Kv7.1 Potassium Channel Gating Module: Studies of the Intracellular C-Terminal Domain in Complex with Calmodulin

Sachyani, D.Dvir, M.Strulovich, R.Tria, G.Tobelaim, W.Peretz, A.Pongs, O.Svergun, D.Attali, B.Hirsch, J.A.

(2014) Structure 22: 1582

  • DOI: 10.1016/j.str.2014.07.016
  • Primary Citation of Related Structures:  

  • PubMed Abstract: 
  • Kv7 channels tune neuronal and cardiomyocyte excitability. In addition to the channel membrane domain, they also have a unique intracellular C-terminal (CT) domain, bound constitutively to calmodulin (CaM). This CT domain regulates gating and tetrame ...

    Kv7 channels tune neuronal and cardiomyocyte excitability. In addition to the channel membrane domain, they also have a unique intracellular C-terminal (CT) domain, bound constitutively to calmodulin (CaM). This CT domain regulates gating and tetramerization. We investigated the structure of the membrane proximal CT module in complex with CaM by X-ray crystallography. The results show how the CaM intimately hugs a two-helical bundle, explaining many channelopathic mutations. Structure-based mutagenesis of this module in the context of concatemeric tetramer channels and functional analysis along with in vitro data lead us to propose that one CaM binds to one individual protomer, without crosslinking subunits and that this configuration is required for proper channel expression and function. Molecular modeling of the CT/CaM complex in conjunction with small-angle X-ray scattering suggests that the membrane proximal region, having a rigid lever arm, is a critical gating regulator.



Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
POTASSIUM VOLTAGE-GATED CHANNEL SUBFAMILY KQT MEMBER 1
A, B
112Homo sapiensMutation(s): 2 
Gene Names: KCNQ1 (KCNA8, KCNA9, KVLQT1)
Find proteins for P51787 (Homo sapiens)
Go to Gene View: KCNQ1
Go to UniProtKB:  P51787
Entity ID: 2
MoleculeChainsSequence LengthOrganismDetails
CALMODULIN
C, D
149Homo sapiensMutation(s): 0 
Gene Names: CALM1 (CALM, CAM, CAM1)
Find proteins for P0DP23 (Homo sapiens)
Go to Gene View: CALM1
Go to UniProtKB:  P0DP23
Small Molecules
Ligands 3 Unique
IDChainsName / Formula / InChI Key2D Diagram3D Interactions
K
Query on K

Download SDF File 
Download CCD File 
A, B, C
POTASSIUM ION
K
NPYPAHLBTDXSSS-UHFFFAOYSA-N
 Ligand Interaction
SCN
Query on SCN

Download SDF File 
Download CCD File 
A
THIOCYANATE ION
C N S
ZMZDMBWJUHKJPS-UHFFFAOYSA-M
 Ligand Interaction
CA
Query on CA

Download SDF File 
Download CCD File 
C, D
CALCIUM ION
Ca
BHPQYMZQTOCNFJ-UHFFFAOYSA-N
 Ligand Interaction
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 3 Å
  • R-Value Free: 0.247 
  • R-Value Work: 0.213 
  • Space Group: P 65
Unit Cell:
Length (Å)Angle (°)
a = 151.760α = 90.00
b = 151.760β = 90.00
c = 56.091γ = 120.00
Software Package:
Software NamePurpose
PHENIXrefinement
HKL-2000data scaling
HKL-2000data reduction

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History 

Deposition Data

Revision History 

  • Version 1.0: 2014-11-05
    Type: Initial release
  • Version 1.1: 2014-12-17
    Type: Database references