Crystal structure of the nonerythroid alpha-spectrin tetramerization site reveals differences between erythroid and nonerythroid spectrin tetramer formation.

ABSTRACT: We have solved the crystal structure of a segment of nonerythroid alpha-spectrin (alphaII) consisting of the first 147 residues to a resolution of 2.3 A. We find that the structure of this segment is generally similar to a corresponding segment from erythroid alpha-spectrin (alphaI) but exhibits unique differences with functional significance. Specific features include the following: (i) an irregular and frayed first helix (Helix C'); (ii) a helical conformation in the junction region connecting Helix C' with the first structural domain (D1); (iii) a long A(1)B(1) loop in D1; and (iv) specific inter-helix hydrogen bonds/salt bridges that stabilize D1. Our findings suggest that the hydrogen bond networks contribute to structural domain stability, and thus rigidity, in alphaII, and the lack

SUBMITTER: Mehboob S 

PROVIDER: S-EPMC2863205 | biostudies-literature | 2010 May

REPOSITORIES: biostudies-literature