Editors' ChoiceTranscription

Topo IIβ Gets to Work

Science's STKE  27 Jun 2006:
Vol. 2006, Issue 341, pp. tw218
DOI: 10.1126/stke.3412006tw218

DNA topoisomerases regulate conformational changes in DNA topology by catalyzing DNA strand breakage and rejoining. Topoisomerase IIβ (Topo IIβ) alters DNA conformation near gene promoters and associates with sequence-specific transcription factors and chromatin modifying and remodeling factors. Ju et al. now show that DNA Topo IIβ generates double-strand breaks at transcriptional promoters when these genes are activated in a signal-dependent manner. Subsequently, DNA repair enzymes are activated and there is a resultant exchange in histone composition and local chromatin structure.

B.-G. Ju, V. V. Lunyak, V. Perissi, I. Garcia-Bassets, D. W. Rose, C. K. Glass, M. G. Rosenfeld, A topoisomerase IIβ-mediated dsDNA break required for regulated transcription. Science 312, 1798-1802 (2006). [Abstract] [Full Text]

J.-F. Haince, M. Rouleau, G. G. Poirier, Gene expression needs a break to unwind before carrying on. Science 312, 1752-1753 (2006). [Summary] [Full Text]