Iimashimizu M.,National Cancer Iinstitute |
Shimamoto N.,Kyoto Sangyo University |
Oshima T.,Nara Institute of Science and Technology |
Kashlev M.,National Cancer Iinstitute
Transcription | Year: 2014
Regulation of transcription elongation via pausing of RNA polymerase has multiple physiological roles. The pausing mechanism depends on the sequence heterogeneity of the DNA being transcribed, as well as on certain interactions of polymerase with specific DNA sequences. Iin order to describe the mechanism of regulation, we introduce the concept of heterogeneity into the previously proposed alternative models of elongation, power stroke and Brownian ratchet. Wwe also discuss molecular origins and physiological significances of the heterogeneity. © 2014 Landes Bioscience.
Baranello L.,National Cancer Iinstitute |
Kouzine F.,National Cancer Iinstitute |
Levens D.,National Cancer Iinstitute
Transcription | Year: 2013
Chromatin is dynamically changing its structure to accommodate and control DNA-dependent processes inside of eukaryotic cells. These changes are necessarily linked to changes of DNA topology, which might itself serve as a regulatory signal to be detected by proteins. Thus, DNA Topoisomerases may contribute to the regulation of many events occurring during the transcription cycle. Iin this review we will focus on DNA Topoisomerase functions in transcription, with particular emphasis on the multiplicity of tasks beyond their widely appreciated role in solving topological problems associated with transcription elongation. © 2013 Landes Bioscience.