3DD4

Structural Basis of KChIP4a Modulation of Kv4.3 Slow Inactivation


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 3 Å
  • R-Value Free: 0.299 
  • R-Value Work: 0.239 

wwPDB Validation 3D Report Full Report


This is version 1.1 of the entry. See complete history

Literature

Structural Insights into KChIP4a Modulation of Kv4.3 Inactivation.

Liang, P.Wang, H.Chen, H.Cui, Y.Gu, L.Chai, J.Wang, K.

(2009) J.Biol.Chem. 284: 4960-4967

  • DOI: 10.1074/jbc.M807704200

  • PubMed Abstract: 
  • Dynamic inactivation in Kv4 A-type K(+) current plays a critical role in regulating neuronal excitability by shaping action potential waveform and duration. Multifunctional auxiliary KChIP1-4 subunits, which share a high homology in their C-terminal ...

    Dynamic inactivation in Kv4 A-type K(+) current plays a critical role in regulating neuronal excitability by shaping action potential waveform and duration. Multifunctional auxiliary KChIP1-4 subunits, which share a high homology in their C-terminal core regions, exhibit distinctive modulation of inactivation and surface expression of pore-forming Kv4 subunits. However, the structural differences that underlie the functional diversity of Kv channel-interacting proteins (KChIPs) remain undetermined. Here we have described the crystal structure of KChIP4a at 3.0A resolution, which shows distinct N-terminal alpha-helices that differentiate it from other KChIPs. Biochemical experiments showed that competitive binding of the Kv4.3 N-terminal peptide to the hydrophobic groove of the core of KChIP4a causes the release of the KChIP4a N terminus that suppresses the inactivation of Kv4.3 channels. Electrophysiology experiments confirmed that the first N-terminal alpha-helix peptide (residues 1-34) of KChIP4a, either by itself or fused to N-terminal truncated Kv4.3, can confer slow inactivation. We propose that N-terminal binding of Kv4.3 to the core of KChIP4a mobilizes the KChIP4a N terminus, which serves as the slow inactivation gate.


    Organizational Affiliation

    Department of Neurobiology, Neuroscience Research Institute, Key Laboratory for Neuroscience of the Ministry of Education, Center for Protein Sciences, Peking University, 38 Xueyuan Road, Beijing 100083, China.




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
Kv channel-interacting protein 4
A
229Mus musculusMutation(s): 0 
Gene Names: Kcnip4 (Calp, Kchip4)
Find proteins for Q6PHZ8 (Mus musculus)
Go to UniProtKB:  Q6PHZ8
Small Molecules
Ligands 1 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
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 3 Å
  • R-Value Free: 0.299 
  • R-Value Work: 0.239 
  • Space Group: I 41
Unit Cell:
Length (Å)Angle (°)
a = 96.300α = 90.00
b = 96.300β = 90.00
c = 71.100γ = 90.00
Software Package:
Software NamePurpose
CrystalCleardata collection
CNSrefinement
DENZOdata reduction
SCALEPACKdata scaling
AMoREphasing

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History 

Deposition Data

Revision History 

  • Version 1.0: 2008-12-23
    Type: Initial release
  • Version 1.1: 2011-07-13
    Type: Derived calculations, Version format compliance