Genomic Approaches to Studying Transcription in the Protozoan Model Tetrahymena Thermophila

<p>This aim of this research is to increase understanding on the process of transcription regulation using the model organism Tetrahymena thermophila. In the first aim of this research, I used the proteomic approach of affinity purification followed by mass spectrometry (AP-MS) in order to establish the conserved protein Anqa1 as a member of a MuvB-like complex in Tetrahymena. AP-MS identified high confidence interactions with Lin9 and RebL1, reinforcing the idea that these three proteins represent the core of a putative MuvB complex. AP-MS revealed interactions with other proteins such as the transcription factor MybL1, suggesting a potential formation of the activator MMB complex in Tetrahymena as seen in the interaction between MuvB and B-MYB in mammals. As part of this aim I also used Chromatin Immunoprecipitation followed by high-throughput sequencing (ChIP-Seq) to detect Anqa1 binding sites and provide insight to its function, which helped discover a potential role of Anqa1 in transcription regulation. In the second aim of this research, to assist in the future characterization of the Mediator subunit Med31, I engineered a functional Med31-BirA* strain of Tetrahymena towards proximity labelling of Mediator associated proteins.</p>