Author ORCID Identifier
Year of Publication
Master of Science (MS)
Arts and Sciences
Dr. Samuel G. Awuah
RNR Polymerase I (RNA Pol I) is a “factory” that orchestrate the transcription of ribosomal rRNA for constructing ribosomes as a primary workshop for protein translation to sustain cell growth. Misregulation of RNA Pol I can cause uncontrolled cell proliferation, which leads to the development of cancer. Yeast (Saccharomyces cerevisiae) is a valuable model system to study RNA Pol I. Recently, the X-ray crystal structure of the yeast homologue of RNA Pol I was elucidated, offering the structural basis to selectively target this transcriptional machinery. The approach to selective RNA Pol I targeting was to disrupt the interaction between a specific transcription factor, RRN3 that bind distinct regions of RNA Pol I. For this purpose, a recombined plasmid was designed to carry human rDNA plus its promoter as target together with a selection marker gene. Therefore, this plasmid could not only introduce the target gene into the yeast (host), but also facilitate the passage of this target gene into a stable yeast strain. In this project, one uracil deficient yeast strain of YBR140C was transformed with the recombined yeast integrative plasmid of pHmrDNA-YIPlac211-TG1. This is a recombined plasmid containing not only the human rDNA but also the URA3 gene as a selection marker. PCR amplification of the human ribosomal DNA was indicative of successful integration of the human ribosomal DNA into the genome of the two yeast strains. Virtual screening using a library of 700 FDA-approved compounds was docked into the RRN3-RNA Pol I complex to identify small molecule disruptors of the RRN3-RNA Pol I as a selective strategy. Using growth assays, gel electrophoresis and transcriptional assays, we identified cerivastatin sodium as a lead virtual hit. The result implicates cerivastatin sodium as a selective RNA Pol I inhibitor worthy of further development with potential as targeted anticancer therapeutic.
Digital Object Identifier (DOI)
Starting Funding of Faculty at Department of Chemistry, University of Kentucky
Tan, Xiao, "DISCOVERY OF SELECTIVE PROBES TARGETING RNA POLYMERASE I" (2019). Theses and Dissertations--Chemistry. 113.