Crystal structure of the alpha-actinin rod reveals an extensive torsional twist.
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.
Ylänne
J
J
European Molecular Biology Laboratory, EMBL, Structural and Computational Biology Programme, Meyerhofstrasse 1, D-69117, Heidelberg, Germany. ylanne@embl-heidelberg.de
Scheffzek
K
K
Young
P
P
Saraste
M
M
D000185:Actinin / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism; D000595:Amino Acid Sequence; D018360:Crystallography, X-Ray; D019281:Dimerization; D004926:Escherichia coli / Q000235:genetics; D006801:Humans; D008958:Models, Molecular; D008969:Molecular Sequence Data; D011487:Protein Conformation; D011994:Recombinant Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism
D011994:Recombinant Proteins; D000185:Actinin