David Epel Websites: Epel Lab Sea Urchin Embryology Virtual Urchin
Recently Epel has turned his attention to how development takes place in the marine environment, especially how embryos resist the effects of such environmental stresses as ultraviolet radiation, pathogens and natural and man-made toxins. Epel's group is looking at these questions from a cellular and molecular viewpoint, and finding unsuspected and novel adaptation that permit embryo survival in these potentially harsh environments. As regards protection from toxins, Epel's lab is focusing on the role of multidrug transporters in protecting embryos (and adults) from the adverse effects of natural and man-introduced toxins on developmental processes. Their work on protection from pathogens focuses on the role of symbiotic bacteria in protecting eggs from other microbes and fungi. Finally, their work on protection from UV damage is focused on the role of "sunscreens," natural pigments that are concentrated in eggs, to protect them from the harmful effects of ultraviolet radiation. Professor Epel has been a Guggenheim Fellow, and is a Fellow of the American Association for the Advancement of Science. Past members of his research group have joined the faculties of the University of California at San Diego, Vanderbilt University, Case-Western Reserve University, the University of Texas at Austin, the University of Munich, and the University of Wisconsin at Madison. Selected Publications Eufemia, N., et al. 2002. Algal products as naturally occurring substrates for p-glycoprotein in Mytilus californianus. Marine Biology. 140(2):343-353.Epel, D. and T. Smital. 2001. Multidrug/multixenobiotic transporters and their significance with respect to environmental levels of pharmaceuticals and personal care products. In: Pharmaceuticals and Personal Care Products in the Environment: Scientific and Regulatory Issues ed. by C. Daughton and R. Ternes Washington, D.C.: American Chemical Society, pp. 244-263. Kurelec, B, et al. 2000. Multixenobiotic resistance, P-glycoprotein, and chemosensitizers. Ecotoxicology. 9(5):307-327. Eufemia, N.A. and D. Epel. 2000. Induction of the multixenobiotic defense mechanism (MXR), P-glycoprotein, in the mussel Mytilus californianus as a general cellular response to environmental stresses. Aquatic Toxicology. 49(1/2):89-100. Kuo, R.C., et al. 2000. NO is a necessary and sufficient requirement of egg activation at fertilization. Nature. 406:633-636. Epel, D., et al.. 1999. Development in the floating world: defenses of eggs and embryos against damage from UV radiation. American Zoologist. 39:271-279. Minier, C., N. Eufemia, and D. Epel. 1999. The multi-xenobiotic resistance phenotype as a tool to biomonitor the environment. Biomarkers. 4(6):442-454. Kaufman, M., et al. 1998. Bacterial symbionts colonize the accessory nidamental gland of the squid Loligo opalescens via horizontal transmission. Biological Bulletin. 194:36-43. Epel, D. 1998. Use of multidrug transporters as first lines of defense against toxins in aquatic organisms. Comparative Biochemistry and Physiology A. 120:23-28. Epel, D. 1997. Activation of sperm and egg during fertilization. In: Handbook of Physiology, Section 14, Cell Physiology ed. by J.F. Hoffman and J.D. Jamieson. New York: Oxford University Press, pp.859-884. Epel, D. 1977. The program of fertilization. Scientific American. 237:128-139. |
David Epel earned his Ph.D. at the University of California at Berkeley. Using gametes from sea urchins, which are easily fertilized in vitro, his laboratory has provided important insights on how development is initiated at fertilization. Of special interest is the dormant metabolism of the egg, and how the activity of these cells is radically altered in the process of fertilization. Epel's research has shown that the change that initiates egg development is a transient rise in free calcium and a permanent increase in intracellular pH. They are currently investigating how contact between sperm and egg induces these changes and especially how the rise in calcium and pH are responsible for initiating new cell activity. Current work focuses on the novel idea that the primary consequence of sperm-egg contact is stimulation of nitric oxide synthase and the formation of nitric oxide which then leads to the calcium increase. This research has provided one of the most detailed descriptions of a developmental program, has relevance to assisted reproduction technology in humans and even has relevance to improvement of animal cloning.