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bioRxiv · 10.1101/850263

G-Quadruplexes Act as Sequence Dependent Chaperones via Protein Oligomerization

Begeman, A.·Litberg, T. J.·Bourne, J.·Xuan, Z.·Horowitz, S.
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Abstract

Maintaining proteome health is important for cell survival. Nucleic acids possess the ability to prevent aggregation up to 300-fold more efficiently than traditional chaperone proteins. In this study, we explore the sequence specificity of the chaperone activity of nucleic acids. Evaluating over 500 nucleic acid sequences effects on aggregation, we demonstrate that the holdase chaperone effect of nucleic acids is highly sequence dependent. Quadruplexes are found to have especially potent effects on aggregation with many different proteins via quadruplex:protein oligomerization. These observations contextualize recent reports of quadruplexes playing important roles in aggregation-related diseases, such as Fragile X and Amyotrophic lateral sclerosis (ALS).

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Begeman, A., Litberg, T. J., Bourne, J., Xuan, Z., Horowitz, S.. 2019-11-21. G-Quadruplexes Act as Sequence Dependent Chaperones via Protein Oligomerization. https://doi.org/10.1101/850263

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