A Low-Cost Electroporator for Genetically Modifying Social Amoeba Dictyostelium Discoideum

Abstract

The social amoeba Dictyostelium discoideum is a commonly used eukaryotic model organism for the study of cell division, chemotaxis, differentiation, phagocytosis, and other cellular processes. Electroporation is an effective and efficient method for delivering plasmid DNA into D. discoideum, an invaluable tool for studying intracellular processes. The technology is readily available but often prohibitively expensive. Although several custom-built electroporation devices have been developed, none deliver the specific 8.5kV/cm exponentially decaying waveform required for D. discoideum transformation. The present study examined whether a simple, inexpensive device can be built to produce this waveform through a simple resistor-capacitor (RC) circuit. A pulse generator RC circuit was built incorporating inexpensive electronic components and a 3D printed cuvette chamber. All four possible combinations of custom-built and commercial pulse generators and custom-built and commercial cuvette chambers were used to transform D. discoideum cells with a plasmid encoding green fluorescent protein (GFP). There were no significant differences in the number of surviving cells immediately following or 24 hours post-transformation between the systems. All combinations of custom-built and commercial systems achieved comparably high transformation efficiency shown by percent of cells expressing GFP six days after the transformation. Since the waveform-specific electroporation system we present here can be built by non-experts with easily obtainable materials and 3D printing, we envision this device to benefit investigators in areas with low research budgets and educators in multiple STEM fields.