University of Pittsburgh Department of Biological Sciences Presents:
- Friday Noon Seminar Series 2017-2018
- Graduate Student: Mitchell Ellison
- Arndt Lab
"Understanding the functions and recruitment of a key epigenetic regulator"
The transcription cycle is carried out by RNA polymerase II (Pol II) and occurs in three steps: initiation, elongation, and termination. At each step of this cycle regulation is imposed on Pol II. One way that Pol II is regulated in eukaryotes is by recruitment of regulatory proteins via modified histones. Histones package DNA into nucleosomes, the building blocks of chromatin. Histone modifications are found in stereotypical patterns at coding regions and in many cases, have been shown to affect transcription. One protein complex required for maintaining proper histone modification patterns is the polymerase associated factor 1 complex (Paf1C). Paf1C promotes a specific subset of histone modifications that are conserved from yeast to humans. I have investigated the effects of Paf1C loss on the Saccharomyces cerevisiae transcriptome using whole genome tiling arrays, RT-qPCR, and comparative bioinformatics analyses. I found that loss of one histone modification promoted by Paf1C, ubiquitylation of histone H2B, does not appear to cause the transcriptional changes I observe in paf1D. Conversely, loss of a tri-methylation mark on histone H3 does correlate with changes in transcription observed in paf1D. Additionally, in a separate project I have investigated an interaction between a member of the Paf1C (Cdc73) and a conserved histone chaperone and elongation factor (Spt6). I conducted in vitro binding assays to assess this interaction and found that a region of Spt6 termed the “Core” is binding to Cdc73 directly.
Friday, November 3, 2017
A219B Langley Hall
12:00 PM Seminar