Coronavirus RNA Synthesis Takes Place within Membrane-Bound Sites.
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ABSTRACT:
SUBMITTER: Doyle N
PROVIDER: S-EPMC8708976 | biostudies-literature |
REPOSITORIES: biostudies-literature
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Project description:Studies in epitranscriptomics indicates that RNA is modified by a variety of enzymes. Among these RNA modifications, A-to-I RNA editing occurs frequently in the mammalian transcriptome. These RNA editing sites can be detected directly from RNA-seq data by examining nucleotide changes from adenosine (A) to guanine (G), which substitutes for inosine (I). However, a careful investigation of such nucleotide changes must be conducted to distinguish sequencing errors and genomic mutations from the genuine editing sites. Building upon our recent introduction of an easy-to-use bioinformatics tool, RNAEditor, to detect RNA editing events from RNA-seq data, we examined the extent by which RNA editing events affects the binding of RNA-binding proteins (RBP). Through employing bioinformatic techniques, we uncover that RNA editing sites occur frequently in RBP-bound regions. Moreover, the presence of RNA editing sites are more frequent when RNA editing islands are examined, which are regions in which RNA editing sites are present in clusters. When the binding of one RBP, HuR, was quantified experimentally, its binding was reduced upon silencing of the RNA editing enzyme ADAR compared to the control—suggesting that the presence of RNA editing islands influences HuR binding to its target regions. These data indicate RNA editing as an important mediator of RBP-RNA interactions—a mechanism which likely constitutes an additional mode of post-transcription gene regulation in biological systems.
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