John Gerhart

John Gerhart is Professor Emeritus of Cell Biology at the University of California, Berkeley, in the Department of BIO. His research focuses on the early development of the amphibian Xenopus laevis, particularly the development of Spemann's organizer, which induces most dorsal and anterior structures of the embryonic body axis. He also studies cortical rotation, a 30° shift of the surface layer of the single-celled egg relative to the cytoplasmic core during the first cell cycle after fertilization. The direction of rotation is predictive of the site from which the organizer and dorsal structures develop. If rotation is blocked, the egg forms no organizer and develops as a radially symmetric embryo. His work explores the mechanisms of microtubule-mediated transport and the role of beta-catenin in organizer formation.