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Compaction of RNA Duplexes in the Cell*.

ABSTRACT: The structure and flexibility of RNA depends sensitively on the microenvironment. Using pulsed electron-electron double-resonance (PELDOR)/double electron-electron resonance (DEER) spectroscopy combined with advanced labeling techniques, we show that the structure of double-stranded RNA (dsRNA) changes upon internalization into Xenopus laevis oocytes. Compared to dilute solution, the dsRNA A-helix is more compact in cells. We recapitulate this compaction in a densely crowded protein solution. Atomic-resolution molecular dynamics simulations of dsRNA semi-quantitatively capture the compaction, and identify non-specific electrostatic interactions between proteins and dsRNA as a possible driver of this effect.

SUBMITTER: Collauto A

PROVIDER: S-EPMC7756485 | biostudies-literature | 2020 Dec

REPOSITORIES: biostudies-literature

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Compaction of RNA Duplexes in the Cell*.

Collauto Alberto A von Bülow Sören S Gophane Dnyaneshwar B DB Saha Subham S Stelzl Lukas S LS Hummer Gerhard G Sigurdsson Snorri T ST Prisner Thomas F TF

Angewandte Chemie (International ed. in English) 20201013 51

The structure and flexibility of RNA depends sensitively on the microenvironment. Using pulsed electron-electron double-resonance (PELDOR)/double electron-electron resonance (DEER) spectroscopy combined with advanced labeling techniques, we show that the structure of double-stranded RNA (dsRNA) changes upon internalization into Xenopus laevis oocytes. Compared to dilute solution, the dsRNA A-helix is more compact in cells. We recapitulate this compaction in a densely crowded protein solution. At ...[more]

PMID: 32804430

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