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R-Loop Formation In Trans at an AGGAG Repeat.

ABSTRACT: Formation of RNA-DNA hybrid, or R-loop, was studied in vitro by transcribing an AGGAG repeat with T7 RNA polymerase. When ribonuclease T1 was present, R-loop formation in cis was diminished, indicating that the transcript was separated from the template and reassociated with it. The transcript was found to form an R-loop in trans with DNA comprising the AGGAG repeat, when the DNA was supercoiled. Results of chemical modification indicated that the duplex opened at the AGGAG repeat under negative supercoiling.

SUBMITTER: Toriumi K

PROVIDER: S-EPMC3770058 | biostudies-literature | 2013

REPOSITORIES: biostudies-literature

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R-Loop Formation In Trans at an AGGAG Repeat.

Toriumi Kazuya K Tsukahara Takuma T Hanai Ryo R

Journal of nucleic acids 20130826

Formation of RNA-DNA hybrid, or R-loop, was studied in vitro by transcribing an AGGAG repeat with T7 RNA polymerase. When ribonuclease T1 was present, R-loop formation in cis was diminished, indicating that the transcript was separated from the template and reassociated with it. The transcript was found to form an R-loop in trans with DNA comprising the AGGAG repeat, when the DNA was supercoiled. Results of chemical modification indicated that the duplex opened at the AGGAG repeat under negative ...[more]

PMID: 24066229

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