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Structural dynamics govern substrate recruitment and catalytic turnover in H/ACA RNP pseudouridylation.

ABSTRACT: H/ACA ribonucleoproteins catalyse the sequence-dependent pseudouridylation of ribosomal and spliceosomal RNAs. Here, we reconstitute site-specifically fluorophore labelled H/ACA complexes and analyse their structural dynamics using single-molecule FRET spectroscopy. Our results show that the guide RNA is distorted into a substrate-binding competent conformation by specific protein interactions. Analysis of the reaction pathway using atomic mutagenesis establishes a new model how individual protein domains contribute to catalysis. Taken together, these results identify and characterize individual roles for all accessory proteins on the assembly and function of H/ACA RNPs.

SUBMITTER: Schmidt A

PROVIDER: S-EPMC8354600 | biostudies-literature | 2021 Sep

REPOSITORIES: biostudies-literature

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Structural dynamics govern substrate recruitment and catalytic turnover in H/ACA RNP pseudouridylation.

Schmidt Andreas A Hanspach Gerd G Hengesbach Martin M

RNA biology 20201110 9

H/ACA ribonucleoproteins catalyse the sequence-dependent pseudouridylation of ribosomal and spliceosomal RNAs. Here, we reconstitute site-specifically fluorophore labelled H/ACA complexes and analyse their structural dynamics using single-molecule FRET spectroscopy. Our results show that the guide RNA is distorted into a substrate-binding competent conformation by specific protein interactions. Analysis of the reaction pathway using atomic mutagenesis establishes a new model how individual prote ...[more]

PMID: 33111609

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