Michelle Arbeitman Assistant Professor Molecular & Computational Biology College of Letters Arts & Sciences

Education:
BA 1990 Molecular Cell Biology - University of California, Berkeley
PhD 1998 Developmental Biology - Stanford University, Stanford, California

Postdoctoral Research Fellowship:
1998 - 2003 Stanford University, California

Started at USC: 2003

Research Topics: Developmental Biology, Cellular Neurobiology, Bioinformatics

Research Description

A central question in biology is how do the well-studied genetic regulatory hierarchies coordinate the differentiation of tissues and maintain the differentiated state at a genome wide level. The research in my lab has focused on this question using the sex determination hierarchy in Drosophila as a model. Two central questions have been addressed at a genome-wide level: how is the sex-specific potential for courtship behavior built into the nervous system and how does the sex-specific deployment of a regulatory hierarchy act on a molecular level to generate and maintain aspects of sex-specific differences in adults.

In Drosophila, all aspects of sexual differentiation are under the control of the sex determination hierarchy. This includes differentiation of all sex-specific somatic tissues and all aspects of male courtship behavior. In adults, sex-specific somatic differences include differences in internal and external genitalia, pigmentation, pheromonal profiles, and behavior. Sex-specific courtship behavior in Drosophila consists of a sequence-dependent series of actions (following, tapping, singing, licking) performed by the male towards the female, which ultimately may result in copulation, or rejection of the male by the female.

Using cDNA microarray tools and the wealth of mutants available in the Drosophila sex determination hierarchy, we have identified many new candidates downstream of this regulatory hierarchy. These results can further our understanding of this regulatory network, by identifying the molecular components that are required to both build into the CNS the potential for courtship behavior and those required for the differentiation and maintenance of adult sex-specific differences in tissues required for reproductive behaviors. Furthermore, these genomic studies provide insight into how well-studied regulatory pathways function at a genome-wide level. Ongoing research in the lab includes additional genomic and computational analyses of the sex hierarchy, as well as molecular-genetic analyses of the genes that function in a sex-specific manner in the nervous system and other tissues of the adult.