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bioRxiv · 10.1101/2024.08.11.607499

Nonequilibrium phases of a biomolecular condensate facilitated by enzyme activity

Coupe, S. T.·Fakhri, N.
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Abstract

Biomolecular condensates represent a frontier in cellular organization, existing as dynamic materials driven out of equilibrium by active cellular processes. Here we explore active mechanisms of condensate regulation by examining the interplay between DEAD-box helicase activity and RNA base-pairing interactions within ribonucleoprotein condensates. We demonstrate how the ATP-dependent activity of DEAD-box helicases--a key class of enzymes in condensate regulation--acts as a nonequilibrium driver of condensate properties through the continuous remodeling of RNA interactions. By combining the LAF-1 DEAD-box helicase with a designer RNA hairpin concatemer, we unveil a complex landscape of dynamic behaviors, including time-dependent alterations in RNA partitioning, evolving condensate morphologies, and shifting condensate dynamics. Importantly, we reveal an antagonistic relationship between RNA secondary structure and helicase activity which promotes condensate homogeneity via a nonequilibrium steady state. By elucidating these nonequilibrium mechanisms, we gain a deeper understanding of cellular organization and expand the potential for active synthetic condensate systems.

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Coupe, S. T., Fakhri, N.. 2024-08-11. Nonequilibrium phases of a biomolecular condensate facilitated by enzyme activity. https://doi.org/10.1101/2024.08.11.607499

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