The LIM protein Ajuba is recruited to cadherin-dependent cell junctions through an association with alpha-catenin

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Updated: Aug 8, 2026

Bead Aggregation Assays for the Characterization of Putative Cell Adhesion Molecules
08:15

Bead Aggregation Assays for the Characterization of Putative Cell Adhesion Molecules

Published on: October 17, 2014

Helene Marie1, Stephen J Pratt, Martha Betson

  • 1Medical Research Council Laboratory for Molecular Cell Biology and Department of Physiology, University College London, Gower Street, United Kingdom.

The Journal of Biological Chemistry
|November 6, 2002
PubMed

Insights

The LIM domain protein Ajuba is recruited to cell adhesion complexes, interacting with alpha-catenin and F-actin. Ajuba is crucial for stable cell-cell junctions in keratinocytes, impacting cell adhesion.

Area of Science:

  • Cell Biology
  • Molecular Biology
  • Biochemistry

Background:

  • Cell-cell adhesion is vital for tissue organization, influencing cell growth, fate, and polarity.
  • The molecular mechanisms governing cell junction formation and function are not fully elucidated.
  • LIM domain proteins are implicated in cell fate and growth, with roles at cell-cell contacts still under investigation.

Purpose of the Study:

  • To investigate the role of the LIM domain protein Ajuba at cadherin-dependent cell-cell adhesive complexes.
  • To determine how Ajuba is recruited to cell junctions and its interaction partners.
  • To understand Ajuba's function in cell-cell adhesion.

Main Methods:

  • Immunofluorescence microscopy to visualize Ajuba localization in primary keratinocytes.
  • Co-immunoprecipitation assays to identify Ajuba's interaction partners.
  • Analysis of keratinocytes from Ajuba null mice to assess junctional integrity.

Main Results:

  • Ajuba is recruited in a regulated manner to cadherin-dependent cell-cell adhesive complexes.
  • Ajuba interacts with alpha-catenin and F-actin at these complexes.
  • Alpha-catenin is essential for efficient Ajuba recruitment to cell junctions.
  • Ajuba null keratinocytes display defects in cell-cell junction formation, stability, and function.

Conclusions:

  • Ajuba is identified as a novel component of cadherin-mediated cell-cell junctions.
  • Ajuba likely bridges cadherin complexes to the actin cytoskeleton.
  • Ajuba plays a significant role in the formation and/or stabilization of cell-cell adhesion.

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