alpha-Actinin links LPP, but not zyxin, to cadherin-based junctions

Biochem Biophys Res Commun. 2008 Jun 20;371(1):144-8. doi: 10.1016/j.bbrc.2008.04.018. Epub 2008 Apr 14.

Abstract

The actin regulator VASP localizes to cell-cell junctions and has been implicated in cell-cell adhesion. VASP is recruited to sites of actin dynamics by interactions with proline rich FPPPPP motifs. Zyxin and its relative LPP use FPPPPP motifs to recruit VASP to specific cellular locations, thus directing changes in actin dynamics. It has been proposed that zyxin and LPP localize to cell-cell junctions by binding alpha-actinin. However, the role of alpha-actinin in recruiting zyxin and LPP to cell-cell contacts has not been experimentally tested. Here we use zyxin and LPP fragments to demonstrate that the alpha-actinin binding site of both proteins independently targets to cell-cell junctions. While the alpha-actinin binding site is required for LPP localization and function at cell-cell contacts, zyxin localization and function at cell-cell contacts is independent of the alpha-actinin binding site. Perturbation of LPP function, but not that of zyxin, results in changes in anchoring of alpha-actinin to detergent-insoluble networks at cell-cell contacts.

Publication types

  • Research Support, N.I.H., Extramural

MeSH terms

  • Actinin / analysis
  • Actinin / metabolism*
  • Amino Acid Motifs
  • Animals
  • Binding Sites
  • Cadherins / metabolism*
  • Cell Adhesion Molecules / metabolism
  • Cytoskeletal Proteins / analysis
  • Cytoskeletal Proteins / genetics
  • Cytoskeletal Proteins / metabolism*
  • Dogs
  • Intercellular Junctions / chemistry
  • Intercellular Junctions / metabolism*
  • Microfilament Proteins / metabolism
  • Phosphoproteins / metabolism

Substances

  • Cadherins
  • Cell Adhesion Molecules
  • Cytoskeletal Proteins
  • Microfilament Proteins
  • Phosphoproteins
  • vasodilator-stimulated phosphoprotein
  • Actinin