The primary level at which gene expression is regulated in all celltypes, is transcription of the information stored in DNA into an RNA precursor.
All steps are the target of the regulatory mechanisms in both prokaryotes and eukaryotes.
A lot has been learned about mechanisms governing initiation and elongation of transcription by eukaryotic RNA polymerases, but little is known about termination. Termination of transcription prevents adjacent transcriptional units from interfering with each other in tandemly arranged genes and provides a means of regulating the expression oncogenes, retroviral genes, Immunoglobulin genes and a number of other cellular genes. The main research focus in my laboratory is on molecular mechanisms of transcription elongation and termination by eukaryotic RNA polymerases in Saccharomyces cerevisiae combining biochemical and genetic approaches. I have identified and characterized the structure of the Pol I transcription terminator in S. cerevisiae and showed that termination of Pol I transcription requires the protein Reb1p as transacting factor. I transcription termination using polymerase walking experiments, heteroduplex experiments and incorporation of nucleotide analogs.