Genomic Approaches to Studying Transcription in the Protozoan Model Tetrahymena Thermophila

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.