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Modulation of RNA Condensation by the DEAD-Box Protein eIF4A.

ABSTRACT: Stress granules are condensates of non-translating mRNAs and proteins involved in the stress response and neurodegenerative diseases. Stress granules form in part through intermolecular RNA-RNA interactions, and to better understand how RNA-based condensation occurs, we demonstrate that RNA is effectively recruited to the surfaces of RNA or RNP condensates in vitro. We demonstrate that, through ATP-dependent RNA binding, the DEAD-box protein eIF4A reduces RNA condensation in vitro and limits stress granule formation in cells. This defines a function for eIF4A to limit intermolecular RNA-RNA interactions in cells. These results establish an important role for eIF4A, and potentially other DEAD-box proteins, as ATP-dependent RNA chaperones that limit the condensation of RNA, analogous to the function of proteins like HSP70 in combatting protein aggregates.

SUBMITTER: Tauber D

PROVIDER: S-EPMC7194247 | biostudies-literature | 2020 Feb

REPOSITORIES: biostudies-literature

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Modulation of RNA Condensation by the DEAD-Box Protein eIF4A.

Tauber Devin D Tauber Gabriel G Khong Anthony A Van Treeck Briana B Pelletier Jerry J Parker Roy R

Cell 20200109 3

Stress granules are condensates of non-translating mRNAs and proteins involved in the stress response and neurodegenerative diseases. Stress granules form in part through intermolecular RNA-RNA interactions, and to better understand how RNA-based condensation occurs, we demonstrate that RNA is effectively recruited to the surfaces of RNA or RNP condensates in vitro. We demonstrate that, through ATP-dependent RNA binding, the DEAD-box protein eIF4A reduces RNA condensation in vitro and limits str ...[more]

PMID: 31928844

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