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Switching transcription with bacterial RNA polymerase through photocaging, photorelease and phosphorylation reactions in the major groove of DNA.

ABSTRACT: We report proof of principle biomimetic switching of transcription in vitro through non-natural chemical reactions in the major groove of DNA templates. Photocaged DNA templates containing nitrobenzyl-protected 5-hydroxymethyluracil or - cytosine permitted no transcription with E. coli RNA polymerase (OFF state). Their irradiation with 400 nm light resulted in DNA templates containing hydroxymethylpyrimidines, which switched transcription ON with a higher yield (250-350%) compared to non-modified DNA. Phosphorylation of templates containing 5-hydroxymethyluracil (but not 5-hydroxymethylcytosine) then turned transcription OFF again. It is the first step towards artificial bioorthogonal chemical epigenetics.

SUBMITTER: Vanikova Z

PROVIDER: S-EPMC6457204 | biostudies-literature | 2019 Apr

REPOSITORIES: biostudies-literature

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Switching transcription with bacterial RNA polymerase through photocaging, photorelease and phosphorylation reactions in the major groove of DNA.

Vaníková Zuzana Z Janoušková Martina M Kambová Milada M Krásný Libor L Hocek Michal M

Chemical science 20190304 14

We report proof of principle biomimetic switching of transcription <i>in vitro</i> through non-natural chemical reactions in the major groove of DNA templates. Photocaged DNA templates containing nitrobenzyl-protected 5-hydroxymethyluracil or - cytosine permitted no transcription with <i>E. coli</i> RNA polymerase (OFF state). Their irradiation with 400 nm light resulted in DNA templates containing hydroxymethylpyrimidines, which switched transcription ON with a higher yield (250-350%) compared ...[more]

PMID: 31015933

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