Structural insights into PDZ-mediated interaction of NHERF2 and LPA(2), a cellular event implicated in CFTR channel regulation

Biochem Biophys Res Commun. 2014 Mar 28;446(1):399-403. doi: 10.1016/j.bbrc.2014.02.128. Epub 2014 Mar 12.

Abstract

The formation of CFTR-NHERF2-LPA2 macromolecular complex in airway epithelia regulates CFTR channel function and plays an important role in compartmentalized cAMP signaling. We previously have shown that disruption of the PDZ-mediated NHERF2-LPA2 interaction abolishes the LPA inhibitory effect and augments CFTR Cl(-) channel activity in vitro and in vivo. Here we report the first crystal structure of the NHERF2 PDZ1 domain in complex with the C-terminal LPA2 sequence. The structure reveals that the PDZ1-LPA2 binding specificity is achieved by numerous hydrogen bonds and hydrophobic contacts with the last four LPA2 residues contributing to specific interactions. Comparison of the PDZ1-LPA2 structure to the structure of PDZ1 in complex with a different peptide provides insights into the diverse nature of PDZ1 substrate recognition and suggests that the conformational flexibility in the ligand binding pocket is involved in determining the broad substrate specificity of PDZ1. In addition, the structure reveals a small surface pocket adjacent to the ligand-binding site, which may have therapeutic implications. This study provides an understanding of the structural basis for the PDZ-mediated NHERF2-LPA2 interaction that could prove valuable in selective drug design against CFTR-related human diseases.

Keywords: CFTR; Cystic fibrosis; LPA(2); NHERF2; Scaffold protein; X-ray crystallography.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amino Acid Sequence
  • Binding Sites
  • Crystallography, X-Ray
  • Cystic Fibrosis / drug therapy
  • Cystic Fibrosis / genetics
  • Cystic Fibrosis / metabolism
  • Cystic Fibrosis Transmembrane Conductance Regulator / chemistry*
  • Cystic Fibrosis Transmembrane Conductance Regulator / genetics
  • Cystic Fibrosis Transmembrane Conductance Regulator / metabolism*
  • Drug Design
  • Humans
  • Hydrogen Bonding
  • Hydrophobic and Hydrophilic Interactions
  • Ligands
  • Models, Molecular
  • Molecular Sequence Data
  • Multiprotein Complexes / chemistry
  • Multiprotein Complexes / genetics
  • Multiprotein Complexes / metabolism
  • PDZ Domains
  • Phosphoproteins / chemistry*
  • Phosphoproteins / genetics
  • Phosphoproteins / metabolism*
  • Protein Structure, Quaternary
  • Receptors, Lysophosphatidic Acid / chemistry*
  • Receptors, Lysophosphatidic Acid / genetics
  • Receptors, Lysophosphatidic Acid / metabolism*
  • Recombinant Proteins / chemistry
  • Recombinant Proteins / genetics
  • Recombinant Proteins / metabolism
  • Sequence Homology, Amino Acid
  • Sodium-Hydrogen Exchangers / chemistry*
  • Sodium-Hydrogen Exchangers / genetics
  • Sodium-Hydrogen Exchangers / metabolism*
  • Thiocyanates / metabolism

Substances

  • CFTR protein, human
  • Ligands
  • Multiprotein Complexes
  • Phosphoproteins
  • Receptors, Lysophosphatidic Acid
  • Recombinant Proteins
  • Sodium-Hydrogen Exchangers
  • Thiocyanates
  • sodium-hydrogen exchanger regulatory factor
  • Cystic Fibrosis Transmembrane Conductance Regulator
  • thiocyanate

Associated data

  • PDB/4P0C