Article

Structure of the alpha-actinin rod: molecular basis for cross-linking of actin filaments.

Structural Biology Programme, European Molecular Biology Laboratory, Heidelberg, Germany.
Cell (Impact Factor: 33.12). 09/1999; 98(4):537-46.
Source: PubMed

ABSTRACT We have determined the crystal structure of the two central repeats in the alpha-actinin rod at 2.5 A resolution. The repeats are connected by a helical linker and form a symmetric, antiparallel dimer in which the repeats are aligned rather than staggered. Using this structure, which reveals the structural principle that governs the architecture of alpha-actinin, we have devised a plausible model of the entire alpha-actinin rod. The electrostatic properties explain how the two alpha-actinin subunits assemble in an antiparallel fashion, placing the actin-binding sites at both ends of the rod. This molecular architecture results in a protein that is able to form cross-links between actin filaments.

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