Expression of mRNA Encoding Voltage‐Dependent Ca Channels in Xenopus Oocytes:

We are studying electrically excitable Ca channels with an approach that combines nucleic acid molecular biology and membrane biophysics. Gurdon et al. first employed Xenopus oocytes as a system for heterologous expression of RNA. This system was later adapted for electrophysiological studies of ion channels by Barnard, Miledi, and their colleagues. Although other expression systems are being developed for membrane channels [Claudio et al. and Beam et al., this volume], the oocyte is now the most common, robust, and best-characterized system. Experiments in which channels are expressed by RNA injections in oocytes have at least three major goals.