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bioRxiv · 10.1101/2021.10.23.465590

A Prion that regulates genome diversification

Byers, J. S.·Futia, R. A.·Elgort, A. V.·Lozanoski, T. M.·Garcia, D. M.·Jarosz, D. F.
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Abstract

Epigenetic mechanisms mediate diverse gene expression programs in growth and development. Here we report a protein-based epigenetic element, a prion, formed by the conserved DNA helicase Mph1/FANCM. [MIX+] is a cytoplasmically inherited state with propagation driven by the non-amyloid prion templating of Mph1. [MIX+] provides resistance to DNA damage, a gain-of-function trait that requires helicase activity. [MIX+] reduces mitotic mutation rates, but promotes meiotic crossovers, driving measurable phenotypic diversification in wild outcrosses. Remarkably, [MIX+] can be induced by DNA-damaging stresses in which it is beneficial. Thus, [MIX+] fuels a quasi-Lamarckian form of inheritance that promotes survival of the current generation and diversification of the next.

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Byers, J. S., Futia, R. A., Elgort, A. V., Lozanoski, T. M., Garcia, D. M., Jarosz, D. F.. 2021-10-24. A Prion that regulates genome diversification. https://doi.org/10.1101/2021.10.23.465590

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