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Updated: Aug 4, 2026

Magnetic Tweezers for the Measurement of Twist and Torque
Published on: May 19, 2014
Crystal structure of the alpha-actinin rod reveals an extensive torsional twist
J Ylänne1, K Scheffzek, P Young
1European Molecular Biology Laboratory, EMBL, Structural and Computational Biology Programme, Meyerhofstrasse 1, D-69117, Heidelberg, Germany. ylanne@embl-heidelberg.de
Background:
Alpha-actinin is a ubiquitously expressed protein found in numerous actin structures. It consists of an N-terminal actin binding domain, a central rod domain, and a C-terminal domain and functions as a homodimer to cross-link actin filaments. The rod domain determines the distance between cross-linked actin filaments and also serves as an interaction site for several cytoskeletal and signaling proteins.
Results:
We report here the crystal structure of the alpha-actinin rod. The structure is a twisted antiparallel dimer that contains a conserved acidic surface.
Conclusions:
The novel features revealed by the structure allow prediction of the orientation of parallel and antiparallel cross-linked actin filaments in relation to alpha-actinin. The conserved acidic surface is a possible interaction site for several cytoplasmic tails of transmembrane proteins involved in the recruitment of alpha-actinin to the plasma membrane.
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