2LKO

Structural Basis of Phosphoinositide Binding to Kindlin-2 Pleckstrin Homology Domain in Regulating Integrin Activation


Experimental Data Snapshot

  • Method: SOLUTION NMR
  • Conformers Calculated: 100 
  • Conformers Submitted: 20 
  • Selection Criteria: structures with the lowest energy 

wwPDB Validation 3D Report Full Report


This is version 1.1 of the entry. See complete history

Literature

Structural basis of phosphoinositide binding to kindlin-2 protein pleckstrin homology domain in regulating integrin activation.

Liu, J.Fukuda, K.Xu, Z.Ma, Y.Q.Hirbawi, J.Mao, X.Wu, C.Plow, E.F.Qin, J.

(2011) J.Biol.Chem. 286: 43334-43342

  • DOI: 10.1074/jbc.M111.295352

  • PubMed Abstract: 
  • Kindlins are a subclass of FERM-containing proteins that have recently emerged as key regulators of integrin receptor activation and signaling. As compared with the conventional FERM domain, the kindlin FERM domain contains an inserted pleckstrin hom ...

    Kindlins are a subclass of FERM-containing proteins that have recently emerged as key regulators of integrin receptor activation and signaling. As compared with the conventional FERM domain, the kindlin FERM domain contains an inserted pleckstrin homology (PH) domain that recognizes membrane phosphoinositides, including phosphatidylinositol 4,5-bisphosphate (PIP2) and phosphatidylinositol 3,4,5-trisphosphate (PIP3). Using NMR spectroscopy, we show that PIP3 site-specifically binds to kindlin-2 PH with substantial chemical shift changes that are much larger than PIP2. This suggests an enhanced association of kindlin-2 with membrane as mediated by PIP3 upon its conversion from PIP2 by phosphoinositide-3 kinase, a known regulator of integrin activation. We determined the NMR structure of the kindlin-2 PH domain bound to the head group of PIP3, inositol 1,3,4,5-tetraphosphate (IP4). The structure reveals a canonical PH domain fold, yet with a distinct IP4 binding pocket that appears highly conserved for the kindlin family members. Functional experiments demonstrate that although wild type kindlin-2 is capable of cooperating with integrin activator talin to induce synergistic integrin α(IIb)β(3) activation, this ability is significantly impaired for a phosphoinositide binding-defective kindlin-2 mutant. These results define a specific PIP3 recognition mode for the kindlin PH domain. Moreover, they shed light upon a mechanism as to how the PH domain mediates membrane engagement of kindlin-2 to promote its binding to integrin and cooperation with talin for regulation of integrin activation.


    Organizational Affiliation

    Department of Molecular Cardiology, Lerner Research Institute, Cleveland Clinic, Cleveland, Ohio 44195, USA.




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
Fermitin family homolog 2
A
138Homo sapiensGene Names: FERMT2 (KIND2, MIG2, PLEKHC1)
Find proteins for Q96AC1 (Homo sapiens)
Go to Gene View: FERMT2
Go to UniProtKB:  Q96AC1
Small Molecules
Ligands 1 Unique
IDChainsName / Formula / InChI Key2D Diagram3D Interactions
4IP
Query on 4IP

Download SDF File 
Download CCD File 
A
INOSITOL-(1,3,4,5)-TETRAKISPHOSPHATE
C6 H16 O18 P4
CIPFCGZLFXVXBG-CNWJWELYSA-N
 Ligand Interaction
External Ligand Annotations 
IDBinding Affinity (Sequence Identity %)
4IPKd: 2120 nM PDBBIND
Experimental Data & Validation

Experimental Data

  • Method: SOLUTION NMR
  • Conformers Calculated: 100 
  • Conformers Submitted: 20 
  • Selection Criteria: structures with the lowest energy 
  • Olderado: 2LKO Olderado

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History 

Deposition Data

Revision History 

  • Version 1.0: 2011-10-26
    Type: Initial release
  • Version 1.1: 2011-12-28
    Type: Database references