Mutations and modifications support a 'pitted-flexiball' model for alpha-crystallin.

R H Smulders; M A van Boekel; W W de Jong

doi:10.1016/s0141-8130(98)00016-6

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Mutations and modifications support a 'pitted-flexiball' model for alpha-crystallin.

R H Smulders·M A van Boekel·W W de Jong

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Abstract

alpha-Crystallin is renown for resisting crystallization and electron microscopic image analysis. The spatial conformation thus remaining elusive, the authors explored the structure and chaperone functioning by analyzing the effects of site-directed mutagenesis, the properties of naturally occurring aberrant forms of alpha-crystallin and the influence of chemical modifications. The authors observed that the globular multimeric structure, as well as the chaperoning capacity are remarkably tolerant towards changes and modifications in the primary structure. The essential features of the quaternary structure--globular shape, flexibility, highly polar exterior and accessible hydrophobic surface pockets--support a 'pitted-flexiball' model, which combines tetrameric subunit building blocks in an open micelle-like arrangement.

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Amino Acid Sequence Animals Binding Sites Cattle Crystallins Macromolecular Substances Models, Molecular Mole Rats Molecular Chaperones Molecular Sequence Data Mutagenesis, Site-Directed Mutation Protein Conformation Protein Processing, Post-Translational Rats Journal Article Research Support, Non-U.S. Gov't Research Support, U.S. Gov't, P.H.S.Review

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R H Smulders, M A van Boekel, W W de Jong. Mutations and modifications support a 'pitted-flexiball' model for alpha-crystallin.. https://doi.org/10.1016/s0141-8130(98)00016-6

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