Meeting Abstract

P1.134  Tuesday, Jan. 4  Microelectrode Electroporation of Fluorescent Dyes: Identification of Small Neurons and Muscle Cells SATTERLIE, R.A.*; EICHINGER, J.M.; TILLERY, J.; University of North Carolina Wilmington satterlier@uncw.edu

A commercial microelectrode electroporation system (Axoporator: Axon Instruments) is being used to inject fluorescent dyes into individual neurons and muscle cells in preparations in which the size and complexity of the neural tissue precludes standard intracellular injection of the dyes. The technique requires that the microelectrode be placed next to (or against) the desired cell type, with subsequent pulsing of appropriate currents much like the techniques of more wide-scale electroporation. Dyes used include Lucifer Yellow and carboxyfluorescein, but it is likely any charged dye can be used. We have injected neurons in cnidarians, ctenophores, molluscs, and hemichordates. In addition, we have used the technique to show that neurons and muscle cells in cubomedusae are not dye-coupled. We are currently using this technique to investigate the complex circuitry in cubomedusan and scyphomedusan rhopalia and in the nerve ring of cubomedusae. Preliminary evidence suggests that non-fluorescent markers, like Neurobiotin, can be used as well. This will allow marking of discrete cells for electron microscopic examination following reaction with electron dense chromagens. Microelectrode dye electroporation may be of use for marking cells in very small organisms, including larvae.