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bioRxiv · 10.1101/2022.10.19.512876

ATP modulates self-perpetuating conformational conversion generating structurally distinct yeast prion amyloids that limit autocatalytic amplification

Mahapatra, S.·Sarbahi, A.·Punia, N.·Joshi, A.·Avni, A.·Walimbe, A.·Mukhopadhyay, S.
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Abstract

Prion-like self-perpetuating conformational conversion of proteins into amyloid aggregates is associated with both transmissible neurodegenerative diseases and non-Mendelian inheritance. Here, we demonstrate that ATP modulates the formation and dissolution of amyloids from a yeast prion domain (NM domain of Saccharomyces cerevisiae Sup35) and restricts autocatalytic amplification by controlling the amount of fragmentable and seeding-competent aggregates. ATP, at (high) physiological concentrations in the presence of Mg2+, kinetically accelerates NM aggregation. Interestingly, ATP also promotes phase-separation-mediated aggregation of a human protein harboring a yeast prion-like domain. We also show that ATP dose independently disaggregates preformed NM fibrils. Furthermore, high concentrations of ATP delimited the number of seeds by generating compact, ATP-bound NM fibrils that exhibited nominal fragmentation by either free ATP or Hsp104 disaggregase. Additionally, (low) pathological ATP concentrations restricted autocatalytic amplification by forming structurally distinct seeding-inefficient amyloids. Our results provide mechanistic underpinnings of concentration-dependent chemical chaperoning by ATP against prion-like transmissions.

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Mahapatra, S., Sarbahi, A., Punia, N., Joshi, A., Avni, A., Walimbe, A., Mukhopadhyay, S.. 2022-10-19. ATP modulates self-perpetuating conformational conversion generating structurally distinct yeast prion amyloids that limit autocatalytic amplification. https://doi.org/10.1101/2022.10.19.512876

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