The overarching question that defines the research interests of my laboratory is how cells progressively acquire and maintain their unique identity during early vertebrate embryonic development. We wish to understand the continuous interplay between the cell-cell interactions, gene regulation, and environmental effects that mediate the process by which embryonic cells adopt and maintain a specific fate.
Our focus in on the nervous system and on understanding the molecular mechanisms by which the profound cellular diversity present in the brain and spinal cord is generated. Of particular interest is the process by which neural cells acquire a specific neurotransmitter phenotype that allows the cell to become part of a functional network of neuronal signaling. Also of interest is the early and often continuing, plasticity of this cell fate--and the limits to this plasticity when the embryo is challenged with environmental perturbations such as mercury exposure.
Because of the large embryos, external fertilization, easy access to the presumptive nervous system at early stages, and the well developed embryology and molecular biology, we employ the amphibian Xenopus laevis as the model organism for our experiments. More recently we have begun experiments with planaria as well. Our efforts have focused on the areas outlined below.