ORCID
https://orcid.org/• https://orcid.org/0009-0000-3839-2271
Date of Award
2026
Document Type
Dissertation
Degree Name
Biological Sciences (Ph.D.)
Department
Biological Sciences
First Advisor
Ales Vancura
Second Advisor
Ivana Vancurova,
Third Advisor
Yan Zhu
Abstract
My dissertation includes two projects, centered on transcription regulation by checkpoint kinases of the DNA damage response (DDR). The first project focused on the role of checkpoint kinase Mec1p in transcription termination and regulation of the torpedo exonuclease Rat1p. Termination, closely linked with pre-mRNA 3’ processing, dissociates RNA polymerase II (RNAPII) from DNA and releases the nascent RNA transcript. Efficient termination is required for maintaining a pool of RNAPII that is available for re-entry into new transcription cycle. Previous results showed that inactivation of Mec1p in the absence of exogenous genotoxic stress downregulates the efficiency of transcription termination. This study reveals that Mec1p impacts transcription termination at two distinct steps. Mec1p promotes recruitment of Pcf11p, a subunit of the cleavage factor IA (CF IA) to 3’ ends of genes and regulates the activity of torpedo exonuclease Rat1p. Deletion of Mec1p or mutations that prevent activation of Mec1p partially suppress both transcription termination defects as well as rRNA and snoRNA processing defects in rat1-1 cells. These results suggest that the kinase activity of Mec1p downregulates Rat1p function.
Recommended Citation
Patel, Riddhi, "THE YEAST CHECKPOINT KINASE MEC1P FUNCTIONS IN TRANSCRIPTION TERMINATION BY FACILITATING RECRUITMENT OF PCF11P AND REGULATING THE TORPEDO EXONUCLEASE RAT1P" (2026). Theses and Dissertations. 1060.
https://scholar.stjohns.edu/theses_dissertations/1060