Electroporative uptake of propidium iodide increases when actin networks are chemically disrupted.
Uptake of propidium iodide to control cells and cells with disrupted actin during electroporation is a temperature dependent process, however, the temperature dependence is stronger for control cells.
Activation energy barrier of electroporation is reduced when the actin networks are disrupted.
The observed reduction in activation energy barrier is possibly due to altered cell membrane mechanical properties.
Transient physical disruption of cell membranes by electric pulses (or electroporation) has significance in biomedical and biological applications requiring the delivery of exogenous (bio)molecules to living cells. We demonstrate that actin networks regulate the cell membrane permeability during electroporation. Disruption of actin networks results in increased uptake of membrane-impermeable molecules such as propidium iodide during electroporation. Our experiments at different temperatures ranging from 11 °C to 37 °C show that molecular uptake during electroporation increases with temperature. Furthermore, by examining the temperature-dependent kinetics of propidium iodide uptake, we infer that the activation energy barrier of electroporation is lowered when the actin networks are disrupted. Our numerical calculations of transmembrane voltage show that the reduced activation energy barrier for the cells with disrupted actin is not a consequence of the changes in transmembrane voltage associated with changes in the cell shape due to the disruption of actin, indicating that this could be due to changes in membrane mechanical properties. Our results suggest that the current theoretical models of electroporation should be advanced further by including the contributions of the cytoskeletal networks on the cell membrane permeability during the delivery of exogenous materials.
Temperature dependent kinetics of electroporation
© 2020 The Author(s). Published by Elsevier B.V.