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PubMed · 8925896

The spectrin repeat folds into a three-helix bundle in solution.

J Pascual·M Pfuhl·G Rivas·A Pastore·M Saraste
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Abstract

Spectrin, a major component of the membrane skeleton, is mainly composed of tandemly repeated segments of approx. 106 amino acids. We have undertaken the determination of the three-dimensional structure of a chicken brain alpha-spectrin repeat by heteronuclear multidimensional NMR. Sedimentation equilibrium demonstrates that this repeat is monomeric at the concentration used for NMR (1 mM). Its secondary structure was identified using a collection of sequential and medium range NOEs, chemical shifts, HN-Halpha coupling constants, and relaxation measurements. These data unequivocally demonstrate the presence of three long helices connected by two loops. A set of interhelical NOEs indicates that the helices assemble into a triple helical structure. Our results provide experimental evidence supporting the triple-helical bundle proposed by modelling.

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Amino Acid SequenceAnimalsBrainChickensCloning, MolecularMagnetic Resonance SpectroscopyModels, StructuralMolecular Sequence DataMolecular WeightPolymerase Chain ReactionProtein FoldingProtein Structure, SecondaryRecombinant ProteinsSpectrinJournal ArticleResearch Support, Non-U.S. Gov't

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J Pascual, M Pfuhl, G Rivas, A Pastore, M Saraste. 1996-04-01. The spectrin repeat folds into a three-helix bundle in solution.. https://doi.org/10.1016/0014-5793(96)00251-7

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