DEFINING THE COMPLEXITIES OF MEF2 FUNCTION AND REGULATION IN DROSOPHILA

The development of cardiac and somatic muscle is coordinated by many factors that are highly conserved across species. Mutations in the coding or regulatory sequences of a gene can alter the structure, function or levels of expression of the protein it encodes. We have identified the genetic mechanism underlying the temperature sensitive mutation in MEF2 (myocyte enhancer factor 2), which is required for the differentiation of all muscle lineages. In addition, we have identified a regulatory element upstream of the Mef2 gene that directs its expression from stage fourteen through the end of embryogenesis which is activated by the NK-homeobox transcription factor Tinman and the GATA transcription factor Pannier. Additionally, we have found that Tinman and Pannier work in collaboration with MEF2 to activate the entire cardiac program. Finally, we have purified cardiac cells from Drosophila embryos and have paired-end sequenced their mRNA in order to identify novel factors that contribute to heart development.National Institutes of HealthBiologyDoctoralUniversity of New Mexico. Biology Dept.Cripps, Richard M.Stricker, Stephen A.Adema, CoenraadHathaway, Helen J