Overview of Research Interests
Chromatin Programming and Transcription
Despite this exciting progress there remains much to be learned about how chromatin is programmed and how active or inactive domains are maintained. Our studies of the abundant nuclear enzyme poly(ADP-ribose) polymerase (PARP) and poly(ADP- ribose) glycohydrolase (PARG) demonstrated that it plays novel and previously unknown roles in many of these processes. Distributed evenly along chromatin PARP is responsible for rapid local chromatin decondensation (loosening), which is required for transcriptional activation of many genes within particular chromatin blocks. Previously we have demonstrated that poly(ADP-ribosyl)ation is also involved in heterochromatin formation, the initiation and maintenance of nucleoli and telomere metabolism. The presence of several PARP-related proteins in mammals complicates the analysis and interpretation of results. Fortunately, only a single PARP gene is present in the Drosophila genome, making this animal an invaluable model system to study PARP function. Using Drosophila we study the molecular mechanisms of PARP activation, its action on chromatin and the interaction of PARP with other components of the chromatin remodeling machinery and transcriptional apparatus.