Molecular mechanisms of RNA polymerase--the F/E (RPB4/7) complex is required for high processivity in vitro.
Transcription elongation in vitro is affected by the interactions between RNA polymerase (RNAP) subunits and the nucleic acid scaffold of the ternary elongation complex (TEC, RNAP-DNA-RNA). We have investigated the role of the RNAP subunits F/E (homologous to eukaryotic RPB4/7) during transcription elongation and termination using a wholly recombinant archaeal RNAP and synthetic nucleic acid scaffolds. The F/E complex greatly stimulates the processivity of RNAP, it enhances the formation of full length products, reduces pausing, and increases transcription termination facilitated by weak termination signals. Mutant variants of F/E that are defective in RNA binding show that these activities correlate with the nucleic acid binding properties of F/E. However, a second RNA-binding independent component also contributes to the stimulatory activities of F/E. In summary, our results suggest that interactions between RNAP subunits F/E and the RNA transcript are pivotal to the molecular mechanisms of RNAP during transcription elongation and termination.
Hirtreiter
Angela
A
Division of Biosciences, Institute for Structural and Molecular Biology, University College London, Darwin Building, Gower Street, London WC1E 6BT, UK.
Grohmann
Dina
D
Werner
Finn
F
D019843:Archaeal Proteins / Q000737:chemistry / Q000378:metabolism*; D004247:DNA / Q000378:metabolism; D012321:DNA-Directed RNA Polymerases / Q000737:chemistry / Q000378:metabolism*; D011072:Poly U / Q000737:chemistry; D021122:Protein Subunits / Q000737:chemistry / Q000378:metabolism; D014158:Transcription, Genetic
D019843:Archaeal Proteins; D021122:Protein Subunits; D011072:Poly U; D004247:DNA; D012321:DNA-Directed RNA Polymerases