Nudel and FAK as antagonizing strength modulators of nascent adhesions through paxillin

PLoS Biol. 2009 May 12;7(5):e1000116. doi: 10.1371/journal.pbio.1000116. Epub 2009 May 26.

Abstract

Adhesion and detachment are coordinated critical steps during cell migration. Conceptually, efficient migration requires both effective stabilization of membrane protrusions at the leading edge via nascent adhesions and their successful persistence during retraction of the trailing side via disruption of focal adhesions. As nascent adhesions are much smaller in size than focal adhesions, they are expected to exhibit a stronger adhesivity in order to achieve the coordination between cell front and back. Here, we show that Nudel knockdown by interference RNA (RNAi) resulted in cell edge shrinkage due to poor adhesions of membrane protrusions. Nudel bound to paxillin, a scaffold protein of focal contacts, and colocalized with it in areas of active membrane protrusions, presumably at nascent adhesions. The Nudel-paxillin interaction was disrupted by focal adhesion kinase (FAK) in a paxillin-binding-dependent manner. Forced localization of Nudel in all focal contacts by fusing it to paxillin markedly strengthened their adhesivity, whereas overexpression of structurally activated FAK or any paxillin-binding FAK mutant lacking the N-terminal autoinhibitory domain caused cell edge shrinkage. These results suggest a novel mechanism for selective reinforcement of nascent adhesions via interplays of Nudel and FAK with paxillin to facilitate cell migration.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Carrier Proteins / genetics
  • Carrier Proteins / metabolism*
  • Cell Adhesion*
  • Cell Line
  • Cell Movement
  • Epithelial Cells / metabolism
  • Focal Adhesion Kinase 1 / genetics
  • Focal Adhesion Kinase 1 / metabolism*
  • Gene Expression Regulation*
  • HeLa Cells
  • Humans
  • Kidney / cytology
  • Microscopy, Confocal / methods
  • Mutation
  • Paxillin / genetics
  • Paxillin / metabolism*
  • RNA Interference
  • Time Factors
  • Urinary Bladder / cytology

Substances

  • Carrier Proteins
  • NDEL1 protein, human
  • Paxillin
  • Focal Adhesion Kinase 1
  • PTK2 protein, human