Dear all,

I have been trying to perform targeted gene disruption by homologous recombination in AX4 cells using electroporation with no success. The conditions for electroporation differ in almost every protocol I have laid hands on. This is probably owing to the different apparatus being used. We use a BIO-RAD gene pulser with the following conditions; 1 kV, 3 uF and 200 ohms. We use 0.4 cm cuvettes. Specific questions are, what conditions have been used successfully using this type of apparatus? Is a resistor necessary? Is it better to perform a single pulse or an additional pulse? I welcome any suggestions. Thank you and happy holidays.

William S. Swatson
Graduate Student
Department of Biological Sciences
University of Missouri, Columbia