3ISW

Crystal structure of filamin-A immunoglobulin-like repeat 21 bound to an N-terminal peptide of CFTR


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.8 Å
  • R-Value Free: 0.298 
  • R-Value Work: 0.263 

wwPDB Validation 3D Report Full Report


This is version 1.1 of the entry. See complete history

Literature

Biochemical basis of the interaction between cystic fibrosis transmembrane conductance regulator and immunoglobulin-like repeats of filamin.

Smith, L.Page, R.C.Xu, Z.Kohli, E.Litman, P.Nix, J.C.Ithychanda, S.S.Liu, J.Qin, J.Misra, S.Liedtke, C.M.

(2010) J.Biol.Chem. 285: 17166-17176

  • DOI: 10.1074/jbc.M109.080911

  • PubMed Abstract: 
  • Mutations in the chloride channel cystic fibrosis transmembrane regulator (CFTR) cause cystic fibrosis, a genetic disorder characterized by defects in CFTR biosynthesis, localization to the cell surface, or activation by regulatory factors. It was di ...

    Mutations in the chloride channel cystic fibrosis transmembrane regulator (CFTR) cause cystic fibrosis, a genetic disorder characterized by defects in CFTR biosynthesis, localization to the cell surface, or activation by regulatory factors. It was discovered recently that surface localization of CFTR is stabilized by an interaction between the CFTR N terminus and the multidomain cytoskeletal protein filamin. The details of the CFTR-filamin interaction, however, are unclear. Using x-ray crystallography, we show how the CFTR N terminus binds to immunoglobulin-like repeat 21 of filamin A (FlnA-Ig21). CFTR binds to beta-strands C and D of FlnA-Ig21 using backbone-backbone hydrogen bonds, a linchpin serine residue, and hydrophobic side-chain packing. We use NMR to determine that the CFTR N terminus also binds to several other immunoglobulin-like repeats from filamin A in vitro. Our structural data explain why the cystic fibrosis-causing S13F mutation disrupts CFTR-filamin interaction. We show that FlnA-Ig repeats transfected into cultured Calu-3 cells disrupt CFTR-filamin interaction and reduce surface levels of CFTR. Our findings suggest that filamin A stabilizes surface CFTR by anchoring it to the actin cytoskeleton through interactions with multiple filamin Ig repeats. Such an interaction mode may allow filamins to cluster multiple CFTR molecules and to promote colocalization of CFTR and other filamin-binding proteins in the apical plasma membrane of epithelial cells.


    Organizational Affiliation

    Department of Pediatrics at Rainbow Babies and Children's Hospital and of Physiology and Biophysics, Case Western Reserve University, Willard Alan Bernbaum Center for Cystic Fibrosis Research, Cleveland, Ohio 44106, USA.




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
Filamin-A
A, B
99Homo sapiensMutation(s): 0 
Gene Names: FLNA (FLN, FLN1)
Find proteins for P21333 (Homo sapiens)
Go to Gene View: FLNA
Go to UniProtKB:  P21333
Entity ID: 2
MoleculeChainsSequence LengthOrganismDetails
Cystic fibrosis transmembrane conductance regulator
C
18Homo sapiensMutation(s): 1 
Gene Names: CFTR (ABCC7)
Find proteins for P13569 (Homo sapiens)
Go to Gene View: CFTR
Go to UniProtKB:  P13569
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.8 Å
  • R-Value Free: 0.298 
  • R-Value Work: 0.263 
  • Space Group: P 65 2 2
Unit Cell:
Length (Å)Angle (°)
a = 74.152α = 90.00
b = 74.152β = 90.00
c = 289.063γ = 120.00
Software Package:
Software NamePurpose
REFMACrefinement
PHASERphasing
PDB_EXTRACTdata extraction
d*TREKdata scaling
d*TREKdata reduction

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History 

Deposition Data

Revision History 

  • Version 1.0: 2010-04-07
    Type: Initial release
  • Version 1.1: 2011-07-13
    Type: Version format compliance