Post-transcriptional control of immunoglobulin expression

The early steps of gene expression, from transcription initiation and elongation to RNA processing and transcription termination, are now known to be intimately interconnected and interdependent events. In addition, each step has the potential to be regulated to affect the amount and type(s) of mRNA synthesized at specific times during development, in different tissues or in response to external signals. Therefore, a mechanistic understanding of the connections between the individual steps of gene expression is essential to fully understand regulation of gene expression. To address this, we will explore the mechanistic interconnections between RNA processing events (splicing and cleavage-polyadenylation) and transcription elongation and termination in the immunoglobulin M (1gM or p) gene. The p gene is an excellent system in which to address these questions since its expression is regulated during B lymphocyte maturation at multiple steps, including RNA splicing, cleavage- polyadenylation and transcription termination. In our ongoing studies of alternative RNA processing regulation in the p gene, we have generated an extensive collection of well- characterized modified genes and numerous reagents to analyze p gene expression. We have also generated microarray data from B cells before and after being stimulated to differentiate. In this proposal, we will utilize this unique set of resources to better understand the interconnections between RNA processing reactions and transcription elongation and how they are regulated. The specific aims of this grant are to (1) identify trans-regulators of p alternative RNA processing based microarray data and direct gene expression studies, (2) determine how RNA processing signals affect RNA polymerase II (pot II) elongation, using a combination of nuclear run-on and high-resolution chromatin immunoprecipitation (ChIP) assays and (3) characterize changes in factors associated with elongating p0111 over wild-type and modified p genes in B cells and plasma cells by high-resolution ChIP experiments. The broader impacts of this research include: the involvement of graduate, undergraduate, and, potentially, high school students in the research and their participation in scientific meetings; the majority of students associated with my lab have been female. The Pt of this grant continues to support science in the broader community by participating as a science fair judge, visiting high school classrooms and, as a part-time Associate Vice President for Research at the University of Kentucky and member of the KY Academy of Sciences, supports research in institutions across the state of KY. The data and resources generated from this project will be shared widely with the scientific community through national meeting presentations and publication.