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Non-native beta-sheet formation: insights into protein amyloidosis

Chinlin Guo·Herbert Levine·David A. Kessler
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Abstract

Protein amyloidosis is a cytopathological process characterized by the formation of highly beta-sheet-rich fibrils. How this process occurs and how to prevent/treat the associated diseases are not completely understood. Here, we carry out a theoretical investigation of sequence-independent beta-sheet formation, based on recent findings regarding the cooperativity of hydrogen-bond network formation. Our results strongly suggest that in vivo beta-sheet aggregation is induced by inter-sheet stacking dynamics. This leads to a prediction for the minimal length of susceptible polymer needed to form such an aggregate. Remarkably, the prediction corresponds quite well with the critical lengths detected in poly-glutamine-related diseases. Our work therefore provides a theoretical framework capable of understanding the underlying mechanism and shedding light on therapy strategies of protein amyloidosis.

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Chinlin Guo, Herbert Levine, David A. Kessler. 2002-03-08. Non-native beta-sheet formation: insights into protein amyloidosis. https://arxiv.org/abs/cond-mat/0203200

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