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RNA-DNA differences are generated in human cells within seconds after RNA exits polymerase II.

ABSTRACT: RNA sequences are expected to be identical to their corresponding DNA sequences. Here, we found all 12 types of RNA-DNA sequence differences (RDDs) in nascent RNA. Our results show that RDDs begin to occur in RNA chains ~55 nt from the RNA polymerase II (Pol II) active site. These RDDs occur so soon after transcription that they are incompatible with known deaminase-mediated RNA-editing mechanisms. Moreover, the 55 nt delay in appearance indicates that they do not arise during RNA synthesis by Pol II or as a direct consequence of modified base incorporation. Preliminary data suggest that RDD and R-loop formations may be coupled. These findings identify sequence substitution as an early step in cotranscriptional RNA processing.

SUBMITTER: Wang IX

PROVIDER: S-EPMC4918108 | biostudies-literature | 2014 Mar

REPOSITORIES: biostudies-literature

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RNA-DNA differences are generated in human cells within seconds after RNA exits polymerase II.

Wang Isabel X IX Core Leighton J LJ Kwak Hojoong H Brady Lauren L Bruzel Alan A McDaniel Lee L Richards Allison L AL Wu Ming M Grunseich Christopher C Lis John T JT Cheung Vivian G VG

Cell reports 20140220 5

RNA sequences are expected to be identical to their corresponding DNA sequences. Here, we found all 12 types of RNA-DNA sequence differences (RDDs) in nascent RNA. Our results show that RDDs begin to occur in RNA chains ~55 nt from the RNA polymerase II (Pol II) active site. These RDDs occur so soon after transcription that they are incompatible with known deaminase-mediated RNA-editing mechanisms. Moreover, the 55 nt delay in appearance indicates that they do not arise during RNA synthesis by P ...[more]

PMID: 24561252

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