We primarily use the chicken embryo as a model organism, and approach research questions from the dual perspective of how individual molecules function and how their functions integrate into molecular networks.
One present research emphasis is concerned with understanding epithelial to mesenchymal transition (EMT) during gastrulation. EMT is a fundamental biological process necessary for elaboration of the vertebrate body plan and for organ formation. Aspects of the EMT program are misregulated and/or co-opted in numerous human diseases. During gastrulation, epithelial cells of the epiblast undergo a “classical EMT” to form the mesoderm. Movement of cells from the epithelial epiblast through EMT in the primitive streak to the mesoderm requires less than two hours and corresponds to the upregulation and downregulation of more than 1500 genes that drive complex changes in cell fate and behavior. Studies in the lab seek to understand how transcriptional pathways activated during gastrulation regulate the cell biology of EMT.
Another long standing research focus is to understand how signaling pathways control heart muscle cell development, from the emergence of premyocardial cells during gastrulation to formation of the primitive heart tube. BMP and FGF signaling are well-known regulators cardiogenesis that play an important role in allocating cells to two molecularly distinct regions known as the first and second heart fields. Combining experimental embryology, transcriptional profiling and bioinformatics, studies are investigating how BMP and FGF signaling drive both distinct and overlapping regulatory programs across the heart forming regions of the embryo.
Our laboratory also hosts the GEISHA in situ hybridization database and website (http://geisha.arizona.edu), an NIH funded repository of gene expression information for the chicken embryo. This freely accessible database houses close to 35,000 images showing mRNA expression patterns for several thousand developmentally regulated genes.
I am a member of the Molecular Cardiovascular Research Program (MCRP) and the Bio5 Institute.