7UTJ

Cryogenic electron microscopy 3D map of F-actin bound by human dimeric alpha-catenin

Summary for 7UTJ

• Entry DOI: 10.2210/pdb7utj/pdb
• EMDB information: 26748 26772
• Descriptor: Actin, alpha skeletal muscle, Catenin alpha-1, ADENOSINE-5'-DIPHOSPHATE, ... (5 entities in total)
• Functional Keywords: alpha-catenin, f-actin, f-actin binding protein, cell-cell junction, cell adhesion
• Biological source: Oryctolagus cuniculus (rabbit); More
• Total number of polymer chains: 12
• Total formula weight: 844665.06

Authors

Rangarajan, E.S.,Smith, E.W.,Izard, T. (deposition date: 2022-04-27, release date: 2023-03-08, Last modification date: 2023-03-29)

Primary citation

Rangarajan, E.S.,Smith, E.W.,Izard, T.
Distinct inter-domain interactions of dimeric versus monomeric alpha-catenin link cell junctions to filaments.
Commun Biol, 6:276-276, 2023

PubMed Abstract: Attachment between cells is crucial for almost all aspects of the life of cells. These inter-cell adhesions are mediated by the binding of transmembrane cadherin receptors of one cell to cadherins of a neighboring cell. Inside the cell, cadherin binds β-catenin, which interacts with α-catenin. The transitioning of cells between migration and adhesion is modulated by α-catenin, which links cell junctions and the plasma membrane to the actin cytoskeleton. At cell junctions, a single β-catenin/α-catenin heterodimer slips along filamentous actin in the direction of cytoskeletal tension which unfolds clustered heterodimers to form catch bonds with F-actin. Outside cell junctions, α-catenin dimerizes and links the plasma membrane to F-actin. Under cytoskeletal tension, α-catenin unfolds and forms an asymmetric catch bond with F-actin. To understand the mechanism of this important α-catenin function, we determined the 2.7 Å cryogenic electron microscopy (cryoEM) structures of filamentous actin alone and bound to human dimeric α-catenin. Our structures provide mechanistic insights into the role of the α-catenin interdomain interactions in directing α-catenin function and suggest a bivalent mechanism. Further, our cryoEM structure of human monomeric α-catenin provides mechanistic insights into α-catenin autoinhibition. Collectively, our structures capture the initial α-catenin interaction with F-actin before the sensing of force, which is a crucial event in cell adhesion and human disease.

PubMed: 36928388
DOI: 10.1038/s42003-023-04610-x

Experimental method

ELECTRON MICROSCOPY (2.77 Å)