Emily published her first paper on the discovery of bidirectional promoters in 2021 and has since been trying to figure out how they are controlled. This recent work was published in Nucleic Acids Research today. Emily shows that different types of transcriptional regulator can impact divergent transcription from bidirectional promoters in varying ways. Frequently, activation of one mRNA in a divergent pair causes down regulation of the other. This can be due to RNA polymerase competition, or a direct impact of activator binding, depending on the regulator involved. Emily also shows that gene expression noise, from bidirectional promoters, is impacted by such RNA polymerase competition.
Ksenia’s PhD work has now been published in Nucleic Acids Research. Her paper shows that the Multiple Antibiotic Resistance Activator protein, a transcription factor also known as MarA, distorts DNA base pairing, at positions either side of its DNA target, upon binding the double helix. Ksenia discovered that this DNA distortion can activate transcription if it coincides with the position at which RNA polymerase initiates unwinding of promoters to begin transcription.