9723965 Cordon The long term objective of this research is to understand the structure and function of the repetitive C-terminal domain (CTD) of RNA polymerase II. Our recent studies have shown that the CTD interacts with a novel set of CTD-binding proteins (CBPs). These proteins are related to a set of serine/arginine-rich proteins (SR proteins) that have been shown to be involved in processing pre-mRNA. In addition to specific domains that interact with the CTD, CBPs have conserved domains suggesting interations with other SR proteins and with RNA. We have identified CBPs in mouse, rat, human, and yeast cells. The objective of this research is to determine whether the CTD and the CTD-binding protein Nrd1 play a role in pre-mRNA processing in the yeast Saccharomyces cerevisiae. Specifically we will examine yeast cells expressing mutant forms of the CTD or of the CTD-binding protein Nrd1 for defects in pre-mRNA splicing, in cleavage and polyadenylation, and in transcription elongation. We will also test mammalian CBPs for their ability to complement a yeast NRD1 deletion mutation. These functional studies are designed to test our general hypothesis that the CTD links transcription and pre-mRNA processing in vivo. The construction of genetic and biochemical tools to study post-initiation CTD function in yeast will lay a foundation for more detailed mechanistic studies of both yeast and mammalian CTD-binding proteins and their interaction with phosphorylated forms of RNA polymerase II during transcription elongation. %%% The long term objective of the proposed study is to understand the structure and function of the repetitive C-terminal domain (CTD) of RNA polymerase II. These functional studies are designed to test our general hypothesis that the CTD links transcription and pre-mRNA processing in vivo. The construction of genetic and biochemical tools to study post-initiation CTD function in yeast will lay a foundation for more detailed mechanistic studies of both yeast and mammal ian CTD-binding proteins. ***
