RNA Polymerase binding

*Constitutive or basal level transcription

Allosteric activation of RNA polymerase

Inhibition of transcription

DNA-protein interactions

Negative Control of the lac Operon

Proposed CAP-cAMP Activation of lac Transcription

S.R. Eddy (2001) Noncoding RNA genes and the modern RNA world, Nature Reviews Genetics, 2:919-929

Three major classes of RNA:

Transcription in Eukaryotes

Type Encodes Copies/genome % Total RNA

mRNA proteins Single or few 10%

tRNA functional RNA Few 20%

rRNA functional RNA Many 70%

But there are more!!!

Epitope Tagging of RNA Polymerase II

*Genetically “tag” Polymerase II subunit

*Grow cells in radioactively labeled amino acids

*Allow assembly of active polymerase

*Add antibody that binds epitope

*”Grab” antibody and what ever it is bound to

*SDS electrophoresis

Transcription*RNA polymerase II

Transcription*RNA polymerase II