Structure of the Dimerization and Beta-Catenin-Binding Region of Alpha-Catenin

Mol Cell. 2000 Mar;5(3):533-43. doi: 10.1016/s1097-2765(00)80447-5.

Abstract

In adherens junctions, alpha-catenin links the cadherin-beta-catenin complex to the actin-based cytoskeleton. alpha-catenin is a homodimer in solution, but forms a 1:1 heterodimer with beta-catenin. The crystal structure of the alpha-catenin dimerization domain, residues 82-279, shows that alpha-catenin dimerizes through formation of a four-helix bundle in which two antiparallel helices are contributed by each protomer. A slightly larger fragment, comprising residues 57-264, binds to beta-catenin. A chimera consisting of the alpha-catenin-binding region of beta-catenin linked to the amino terminus of alpha-catenin 57-264 behaves as a monomer in solution, as expected, since beta-catenin binding disrupts the alpha-catenin dimer. The crystal structure of this chimera reveals the interaction between alpha- and beta-catenin, and provides a basis for understanding adherens junction assembly.

Publication types

  • Comparative Study
  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, Non-P.H.S.
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Amino Acid Sequence
  • Binding Sites
  • Conserved Sequence
  • Crystallography
  • Cytoskeletal Proteins / chemistry*
  • Dimerization
  • Intercellular Junctions / chemistry
  • Intercellular Junctions / ultrastructure
  • Models, Molecular
  • Molecular Sequence Data
  • Protein Binding
  • Sequence Homology, Amino Acid
  • Trans-Activators*
  • Vinculin / chemistry
  • alpha Catenin
  • beta Catenin

Substances

  • Cytoskeletal Proteins
  • Trans-Activators
  • alpha Catenin
  • beta Catenin
  • Vinculin

Associated data

  • PDB/1DOV
  • PDB/1DOW