Shoji Osawa, PhD
Education and Training
1979: Ph.D., Tokyo Metropolitan University
Areas of Interest
My overall research interest is to study the regulatory mechanisms of signal transduction by G protein-coupled receptors using the visual system as a model. Two types of photoreceptor cells, rods and cones, mediate the response to light in the mammalian retina. Rods are responsible for vision in dim light. Cones are specialized to detect red, blue or green light through the presence of distinct light-absorbing opsins. Electrophysiological studies have determined that the response to light is more rapid in cones and that they terminate more quickly than rods. The reasons for these differences are not well understood. Most of our knowledge of phototransduction in mammals is derived from studies of the rod cells, because most mammalian retinas are 90 to 95% rods.