Dynamics of RNA polymerase II and elongation factor Spt4/5 recruitment during activator-dependent transcription

Abstract

The synthesis of a eukaryotic messenger RNA molecule involves the association of RNA polymerase and dozens of accessory proteins on DNA. We used differently colored fluorescent dyes to tag DNA, RNA polymerase II, and the elongation factor Spt4/5 in yeast nuclear extract, and then observed the assembly and dynamics of individual molecules of the proteins with single DNA molecules by microscopy. The observations quantitatively define an overall pathway by which transcription complexes form and evolve in response to an activator protein. They suggest how molecular complex dynamics may be tuned to optimize efficient RNA production.