CAREER: Evolution and Constraint of the RNA Polymerase II C-terminal Domain

East Carolina University, Greenville NC

Investigators

Abstract

The strongly conserved C-terminal domain (CTD) of the largest subunit of DNA-dependent RNA polymerase II (RPB1) is essential for mRNA synthesis and is present in all animals, plants and fungi that have been examined. In many groups of organisms, however, the RPB1 C-terminus displays no evidence of sequence elements known to be necessary for CTD function. The implication of these differences for RNA pol II transcription is unclear. This research is aimed at examining the significance of evolutionary changes in RPB1 C-terminal sequences from a functional perspective. Specifically, questions to be investigated are, 1) when in the course of eukaryotic evolution did the CTD become fully integrated into the RNA pol II transcription machine, and 2) which components of that integrated machine enhanced control over mRNA synthesis sufficiently to allow for the emergence of developmentally complex organisms? Special focus will be placed on investigating the molecular biology of red algae, both because they are intermediate in developmental complexity between unicellular protistan groups and more complex multicellular model organisms, and because of their inferred evolutionary history based on RNA polymerase gene sequences. In conjunction with this investigation, a new research-based course for upper division undergraduate and graduate students will be developed, permitting direct participation in the exploration of the molecular biology of diverse eukaryotic organisms. This course also will serve as a springboard for attracting students toward more intensive undergraduate projects relating to the research goals outlined. In addition, it will provide the infrastructure for a summer outreach program that will afford area high school students and teachers a hands-on introduction to basic molecular and evolutionary research.