connecting mutations of the rna polymerase ii c-terminal domain to complex phenotypic changes using combined gene expression and network analyses连接突变的rna聚合酶ii c端域复杂表型变化使用基因表达和网络分析相结合.pdf

Connecting Mutations of the RNA Polymerase II C- Terminal Domain to Complex Phenotypic Changes Using Combined Gene Expression and Network Analyses 1 2 1 Carlyle Rogers *, Zhenhua Guo , John W. Stiller 1 Department of Biology, East Carolina University, Greenville, North Carolina, United States of America, 2 Kunming Institute of Botany, Chinese Academy of Sciences (CAS), Kunming, China Abstract The C-terminal domain (CTD) of the largest subunit in DNA-dependent RNA polymerase II (RNAP II) is essential for mRNA synthesis and processing, through coordination of an astounding array of protein-protein interactions. Not surprisingly, CTD mutations can have complex, pleiotropic impacts on phenotype. For example, insertions of five alanine residues between CTD diheptads in yeast, which alter the CTD’s overall tandem structure and physically separate core functional units, dramatically reduce growth rate and result in abnormally large cells that accumulate increased DNA content over time. Patterns by which specific CTD-protein interactions are disrupted by changes in CTD structure, as well as how downstream metabolic pathways are impacted, are difficult to target for direct experimental analyses. In an effort to connect an altered CTD to complex but quantifiable phenotypic changes, we applied network analyses of genes that are differentially expressed in our five alanine CTD mutant, combined with established genetic interactions from the Saccharomyces cerevisiae Genome Database (SGD). We were able to identify candidate genetic pathways, and several key genes, that could explain how this change in CTD structure leads to the specific phenotypic changes observed. These hypothetical networks identify links between CTD