Homologues of epigenetic pyrimidines and their effect on transcription with bacterial RNA polymerase
The research team led by Michal Hocek from IOCB Prague in collaboration with the group of Libor Krásný from the Institute of Microbiology investigated the modified DNA template transcription efficiency using bacterial RNA polymerase.
The major epigenetic modification of eukaryotic genomic DNA is 5-methylcytosine, and it is an important regulator of gene expression. The scientists designed and synthesized several homologues of epigenetic pyrimidine nucleotides and their corresponding nucleoside triphosphates (dNXTPs). The modified dNXTPs served as substrates for PCR synthesis of modified DNA templates, which enabled studying the transcription with bacterial RNA polymerase. The 5-ethyluracil-bearing templates stimulated the transcription the most leading to a 200% yield compared to natural thymine.
The results indicate that bacterial RNA polymerase can cope with dramatically altered DNA templates, and modified pyrimidine nucleotides could potentially play roles as artificial epigenetic DNA nucleobases.
