期刊名称：Proceedings of the National Academy of Sciences
印刷版ISSN：0027-8424
电子版ISSN：1091-6490
出版年度：2022
卷号：119
期号：34
DOI：10.1073/pnas.2206240119
语种：English
出版社：The National Academy of Sciences of the United States of America
摘要：Significance
We have investigated the usefulness of de novo designed miniproteins, 35 to 48 amino acid residues in length, for the inhibition of protein fibrils associated with numerous neurodegenerative diseases. From known atomic structures of fibrils of tau, alpha-synuclein, and amyloid-beta, we designed miniproteins to cap the growing tips of fibrils, halting further growth. We find the miniproteins halt protein aggregation into fibrils and halt the ability of fibrils to induce or “seed” fibril growth in other cells. A miniprotein that inhibits aggregation of its target protein is specific and does not inhibit aggregation of other proteins. An advantage of miniproteins as eventual therapeutics is that they can be genetically encoded and possibly delivered to diseased brains by viral vectors.
Neurodegenerative diseases are characterized by the pathologic accumulation of aggregated proteins. Known as amyloid, these fibrillar aggregates include proteins such as tau and amyloid-β (Aβ) in Alzheimer’s disease (AD) and alpha-synuclein (αSyn) in Parkinson’s disease (PD). The development and spread of amyloid fibrils within the brain correlates with disease onset and progression, and inhibiting amyloid formation is a possible route toward therapeutic development. Recent advances have enabled the determination of amyloid fibril structures to atomic-level resolution, improving the possibility of structure-based inhibitor design. In this work, we use these amyloid structures to design inhibitors that bind to the ends of fibrils, “capping” them so as to prevent further growth. Using de novo protein design, we develop a library of miniprotein inhibitors of 35 to 48 residues that target the amyloid structures of tau, Aβ, and αSyn. Biophysical characterization of top in silico designed inhibitors shows they form stable folds, have no sequence similarity to naturally occurring proteins, and specifically prevent the aggregation of their targeted amyloid-prone proteins in vitro. The inhibitors also prevent the seeded aggregation and toxicity of fibrils in cells. In vivo evaluation reveals their ability to reduce aggregation and rescue motor deficits in
Caenorhabditis elegans models of PD and AD.
