Control of Pre-mRNA Metabolism in Drosophila

University Of North Carolina At Chapel Hill, Chapel Hill NC

Investigators

Abstract

This project addresses the role of the Drosophila melanogaster gene called suppressor of sable, su(s),in the control of pre-mRNA metabolism. Recent studies from this laboratory indicate that the su(s)gene product, Su(s), associates with a hypophosphorylated form of RNA polymerse II (RNAP II) and performs a novel function in regulating both transcription and an early step in pre-mRNA processing. The project has three main objectives. The first is to gain a better understanding of how Su(s) regulates RNA production. Northern blot and RT-PCR analyses will be used to examine the effect of su(s) mutations on the synthesis and processing of transcripts from genes that have been defined in previous studies as probable targets of Su(s)-mediated regulation. Drosophila genome microarrays will be used to examine the global effect of su(s) mutations on gene expression in embryos and to identify new genes that are regulated by Su(s).The second objective is to investigate the interactions of Su(s) with other proteins and with specific regions of genes. Polytene chromosomes will be probed simultaneously with a polyclonal antibody that recognizes Su(s) and one of several different monoclonal antibodies that recognize specific phosphorylated forms of RNAP II. The chromatin immunoprecipitation (ChIP) technique will be used to examine the distribution of Su(s) and different phosphorylated forms of RNA polymerase II in specific regions of genes. The third objective is to characterize functional domains of Su(s) through in vivo analysis of su(s) transgenes with alterations at specific sites in the coding region. Many cellular processes once thought to be distinct events, separated by time and distance, are now believed to occur at the same time and in the same place, catalyzed by molecular complexes with at least some shared components. This analysis of such a pair of processes, transcription and transcript processing, promises to provide novel insights into the mechanisms used to integrate various metabolic events in higher organisms.