My major research interest is the genetic control of morphogenesis at the interface between the cell and tissue levels. As a model system we have studied the Drosophila wing, which is covered with an array of distally pointing hairs. Some years ago we found hair polarity is controlled via regulating the subcellular location for initiation of the growth of the pupal prehair that gives rise to the adult hair. Distally pointing hairs form at the distal most region of the cell and grow in a distal direction. Mutations that alter polarity always alter the subcellular location for prehair initiation. We have identified and studied at the molecular and genetic levels a number of genes that comprise part of an intercellular signaling and intracellular signal transduction pathway (i.e. the frizzled pathway) that regulates the subcellular location for prehair initiation. A major goal of the lab is to elucidate the who (i.e. which genes and cells are important for sending, receiving and responding to the polarity signal), what (i.e what is the molecular nature of the signal and signal transduction machinery), when (i.e. when does the signaling take place), where (i.e. is there a special population of signaling cells and how does the signal spread across the tissue), and how (i.e. what are the cellular and biochemical mechanisms involved) of this system. Current efforts are primarily concentrated on the inturned-like genes. These genes function downstream of the frizzled-like genes and are required to link the localized accumulation of proteins such as Frizzled and Vang Gogh to the cytoskeleton.
We are also studying how cells insure the integrity of cellular extensions. The morphogenesis of epidermal hairs, arista laterals and sensory bristle shafts share many common features. The function of both the actin and microtubule cytoskeletons is essential for their morphogenesis and many mutations produce similar phenotypic effects in all three of these cell types. Mutations in the tricornered and furry genes result in the splitting of all three extensions and genetic experiments suggest these two genes function in a common pathway that insured extension integrity. We have shown that tricornered encodes the Drosphila NDR kinase and that furry encodes a large conserved protein. We plan to continue to study these genes and proteins and the splitting phenomenon at the cellular and molecular level. Current experiments are making important use of in vivo imaging approaches.
We are also interested in the morphogenesis of appendages and have begun to study this using both genetics and in vivo imaging approaches