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Interpreting reverse transcriptase termination and mutation events for greater insight into the chemical probing of RNA

ABSTRACT: Chemical probing has the power to provide insight into RNA conformation in vivo and in vitro, but interpreting the results depends on methods to detect the chemically modified nucleotides. Traditionally, the presence of modified bases was inferred from their ability to halt reverse transcriptase during primer extension and the locations of termination sites observed by electrophoresis or sequencing. More recently, modification-induced mutations have been used as a readout for chemical probing data. Given variable propensity for mismatch incorporation and read-through with different reverse transcriptases, we examined how termination and mutation events compare to each other in the same chemical probing experiments. We found that mutations and terminations induced by dimethyl sulfate probing are both specific for methylated bases, but these two measures have surprisingly little correlation and represent largely non-overlapping indicators of chemical modification data. We also show that specific biases for modified bases depend partly on local sequence context, and that different reverse transcriptases show different biases toward reading a modification as a stop or a mutation. These results support approaches that incorporate analysis of both termination and mutation events into RNA probing experiments.

ORGANISM(S): Mus musculus

PROVIDER: GSE97609 | GEO | 2017/09/26

SECONDARY ACCESSION(S): PRJNA382421

REPOSITORIES: GEO

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Anomalous reverse transcription through chemical modifications in polyadenosine stretches

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Mus musculus

Project description:Interpreting reverse transcriptase termination and mutation events for greater insight into the chemical probing of RNA

| PRJNA382421 | ENA

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2016-02-09 | E-GEOD-67667 | biostudies-arrayexpress

Chemical modifications mark alternatively spliced and actively degrading messenger RNAs in Arabidopsis and humans

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