The functions of the RNA polymerase II CTD in transcription and RNA processing
type: CreativeWork
description: RNA polymerase II (RNAP II), transcribing messenger RNAs (mRNAs), small nuclear RNAs (snRNAs), and non-coding RNAs (ncRNAs), is composed of 12 subunits. Rpb1, the largest subunit with catalytic polymerase activity, possesses a unique c-terminal domain (CTD) that consists of tandem heptad repeats with the consensus sequence of Tyr-Ser-Pro-Thr-Ser-Pro-Ser (Y1S2P3T4S5P6S7). Somewhat reflecting the complexity of the organism, the number of repeats varies, from 26 in yeast to 52 in vertebrates. The CTD, intensively phosphorylated during transcription, serves a means to coordinate transcription and RNA processing- capping, splicing, and 3' end formation. For example, Ser 5, phosphorylated in the start of transcription, promotes the recruitment of capping enzyme, and Ser 2 phosphorylation facilitates RNA 3' end formation and transcription termination by acting as a landing pad for Pcf11. Detailed introduction is described in Chapter 1. Because of the importance of the CTD in these events, I created an Rpb1 conditional knock-out DT40 cell line (DT40-Rpb1) to further study the CTD with an initial focus on Thr 4, the function of which was unclear. Using DT40-Rpb1 system, we found that Thr 4 was phosphorylated in yeast, fly, chicken, and human cells, and cyclin-dependent kinase (CDK9) was likely the kinase to carry out this phosphorylation. We further provide evidence that Thr 4 functions in histone mRNA 3' end formation (presented mostly in chapter 2 of this thesis). Chapter 3 mainly describes the studies regarding Ser 2, Ser 5, and Ser 7. Based on the DT40-Rpb1 cell line, I created stable cell lines expressing an Rpb1 carrying a CTD with Ser 2, Ser 5, or Ser 7 mutated to alanine, and investigated the phenotypes of these cells. We found that cells expressing an Rpb1 with S2A or S5A mutation were defective in transcription and RNA processing. Contrary to previous findings, we found Ser 7 was not involved in snRNA expression and 3' end processing. In fact, no phenotypes associa…
abstract: RNA polymerase II (RNAP II), transcribing messenger RNAs (mRNAs), small nuclear RNAs (snRNAs), and non-coding RNAs (ncRNAs), is composed of 12 subunits. Rpb1, the largest subunit with catalytic polymerase activity, possesses a unique c-terminal domain (CTD) that consists of tandem heptad repeats with the consensus sequence of Tyr-Ser-Pro-Thr-Ser-Pro-Ser (Y1S2P3T4S5P6S7). Somewhat reflecting the complexity of the organism, the number of repeats varies, from 26 in yeast to 52 in vertebrates. The CTD, intensively phosphorylated during transcription, serves a means to coordinate transcription and RNA processing- capping, splicing, and 3' end formation. For example, Ser 5, phosphorylated in the start of transcription, promotes the recruitment of capping enzyme, and Ser 2 phosphorylation facilitates RNA 3' end formation and transcription termination by acting as a landing pad for Pcf11. Detailed introduction is described in Chapter 1. Because of the importance of the CTD in these events, I created an Rpb1 conditional knock-out DT40 cell line (DT40-Rpb1) to further study the CTD with an initial focus on Thr 4, the function of which was unclear. Using DT40-Rpb1 system, we found that Thr 4 was phosphorylated in yeast, fly, chicken, and human cells, and cyclin-dependent kinase (CDK9) was likely the kinase to carry out this phosphorylation. We further provide evidence that Thr 4 functions in histone mRNA 3' end formation (presented mostly in chapter 2 of this thesis). Chapter 3 mainly describes the studies regarding Ser 2, Ser 5, and Ser 7. Based on the DT40-Rpb1 cell line, I created stable cell lines expressing an Rpb1 carrying a CTD with Ser 2, Ser 5, or Ser 7 mutated to alanine, and investigated the phenotypes of these cells. We found that cells expressing an Rpb1 with S2A or S5A mutation were defective in transcription and RNA processing. Contrary to previous findings, we found Ser 7 was not involved in snRNA expression and 3' end processing. In fact, no phenotypes associa…
author: Hsin, Jing-Ping
language: English
keywords: Molecular biology, Cytology
date published: 2013
date modified: 2026-07-24T01:44:34Z
provider: Columbia University
publisher: Networked Digital Library of Theses and Dissertations
type: WebPage
source organization: Columbia University

PropertyValue
property ID: DOI
value: 10.7916/D8GH9H96