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X-ray structures of isoforms of the actin-binding protein profilin that differ in their affinity for phosphatidylinositol phosphates.

ABSTRACT: We determined the structures of Acanthamoeba profilin I and profilin II by x-ray crystallography at resolutions of 2.0 and 2.8 A, respectively. The polypeptide folds and the actin-binding surfaces of the amoeba profilins are very similar to those of bovine and human profilins. The electrostatic potential surfaces of the two Acanthamoeba isoforms differ. Two areas of high positive potential on the surface of profilin II are candidate binding sites for phosphatidylinositol phosphates. The proximity of these sites to the actin binding site provides an explanation for the competition between actin and lipids for binding profilin.

SUBMITTER: Fedorov AA

PROVIDER: S-EPMC44661 | biostudies-other | 1994 Aug

REPOSITORIES: biostudies-other

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X-ray structures of isoforms of the actin-binding protein profilin that differ in their affinity for phosphatidylinositol phosphates.

Fedorov A A AA Magnus K A KA Graupe M H MH Lattman E E EE Pollard T D TD Almo S C SC

Proceedings of the National Academy of Sciences of the United States of America 19940801 18

We determined the structures of Acanthamoeba profilin I and profilin II by x-ray crystallography at resolutions of 2.0 and 2.8 A, respectively. The polypeptide folds and the actin-binding surfaces of the amoeba profilins are very similar to those of bovine and human profilins. The electrostatic potential surfaces of the two Acanthamoeba isoforms differ. Two areas of high positive potential on the surface of profilin II are candidate binding sites for phosphatidylinositol phosphates. The proximit ...[more]

PMID: 8078936

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