My laboratory studies the mechanisms and effects of calcium signals in polarized epithelia. One aspect of our work is to define how calcium signals are differentially regulated in the nucleus and cytoplasm. This involves identification of distinct calcium stores and release mechanisms in the nucleus, and we are examining whether and how these are activated selectively by growth factors. The second aspect of our work is to examine how calcium waves and other calcium signals regulate secretion in polarized epithelia. Calcium waves preferentially begin in, the apical region of most secretory epithelia, and we are in the process of defining the mechanisms responsible for this. We also are using an adenoviral antisense approach to understand the relative roles of each IP3 receptor isoform in regulating calcium signaling and secretion in vitro and in vivo. Another major focus is to examine intercellular communication of second messenger signals and to establish the mechanism by which gap junctions act in coordinating intercellular spread of Ca2+ waves in isolated pairs and triplets of cells.
Specialized Terms: Mechanisms and effects of calcium signals in polarized epithelia; Effect of spatial organization of calcium signals on organ function regulation; Factors that organize Ca2+ waves in hepatocytes; Organization and effects of Ca2+ waves in cholangiocytes; Mechanisms and effects of Ca2+ signals in the nucleus
Cell Nucleus; Cell Biology; Digestive System Diseases; Liver; Calcium Signaling; Hepatocytes