4IGG

Full-length human alpha-catenin crystal structure

Summary for 4IGG

• Entry DOI: 10.2210/pdb4igg/pdb
• Related: 4ehp
• Descriptor: Catenin alpha-1, PHOSPHATE ION (2 entities in total)
• Functional Keywords: asymmetric dimer, adherens junctions, f-actin binding, cell adhesion
• Biological source: Homo sapiens (human)
• Cellular location: Cytoplasm, cytoskeleton: P35221
• Total number of polymer chains: 2
• Total formula weight: 184605.91

Authors

Izard, T.,Rangarajan, E.S. (deposition date: 2012-12-17, release date: 2012-12-26, Last modification date: 2024-02-28)

Primary citation

Rangarajan, E.S.,Izard, T.
Dimer asymmetry defines alpha-catenin interactions.
Nat.Struct.Mol.Biol., 20:188-193, 2013

PubMed Abstract: The F-actin-binding cytoskeletal protein α-catenin interacts with β-catenin-cadherin complexes and stabilizes cell-cell junctions. The β-catenin-α-catenin complex cannot bind F-actin, whereas interactions of α-catenin with the cytoskeletal protein vinculin appear to be necessary to stabilize adherens junctions. Here we report the crystal structure of nearly full-length human α-catenin at 3.7-Å resolution. α-catenin forms an asymmetric dimer where the four-helix bundle domains of each subunit engage in distinct intermolecular interactions. This results in a left handshake-like dimer, wherein the two subunits have remarkably different conformations. The crystal structure explains why dimeric α-catenin has a higher affinity for F-actin than does monomeric α-catenin, why the β-catenin-α-catenin complex does not bind F-actin, how activated vinculin links the cadherin-catenin complex to the cytoskeleton and why α-catenin but not inactive vinculin can bind F-actin.

PubMed: 23292143
DOI: 10.1038/nsmb.2479

Experimental method

X-RAY DIFFRACTION (3.66 Å)