An Investigation Into The Role Of Cfia 3' End Processing Complex In The Termination And Initiation/reinitiation Of Transcription

AN INVESTIGATION INTO THE ROLE OF CFIA 3' END PROCESSING COMPLEX INTHE TERMINATION AND INITIATION/REINITIATION OF TRANSCRIPTIONbyNADRA Al-HUSINIMay 2014Advisor: Dr. Athar AnsariMajor: Biology Degree: Doctor of PhilosophyIn budding yeast, as in higher eukaryotes, transcription of protein coding genes isexecuted by a highly specialized, conserved polymerase called RNA polymerase II(RNAPII). The transcription cycle of RNAPII has four major steps: initiation, elongation,termination, and reinitiation. The successful accomplishment of each of these stepsrequires a number of accessory factors. Many of these factors operate at multiple stepsin the transcription cycle. The major focus of this study was to examine the function ofClp1, which is an RNA processing factor operating at the 3′ end of genes, in thetranscription cycle. Clp1 is one of the four subunits of the CFIA 3′ end processingcomplex. It is the least investigated CFIA subunit. The role of the other three subunits ofthe CFIA complex in 3' end processing and termination of transcription is welldocumented. Here we investigate the role of Clp1 in the initiation as well as the termination oftranscription. We used a temperature-sensitive mutant of Clp1 to assess its function.We demonstrated a direct role for this factor in the termination of transcription of CHA1. We used three different approaches; TRO assay, RNAPII-ChIP assay, and strand