Aspects of plant plasmalemma charging induced by external electric field pulses.

The charging of the plasmalemma is a necessary condition for permeabilization of the plasma membrane (electroporation) in response to external electric field exposure. Common theories explain this permeabilization by formation of pores in the lipid bilayer. Using pulsed laser fluorescence microscopy, we measured the charging process of the membrane during the application of an external electric field with a temporal resolution of 5 ns.

A patch clamp study on the electro-permeabilization of higher plant cells: Supra-physiological voltages induce a high-conductance, K+ selective state of the plasma membrane.

Permeabilization of biological membranes by pulsed electric fields ("electroporation") is frequently used as a tool in biotechnology. However, the electrical properties of cellular membranes at supra-physiological voltages are still a topic of intensive research efforts. Here, the patch clamp technique in the whole cell and the outside out configuration was employed to monitor current-voltage relations of protoplasts derived from the tobacco culture cell line "Bright yellow-2".

Transmembrane potential measurements on plant cells using the voltage-sensitive dye ANNINE-6.

The charging of the plasma membrane is a necessary condition for the generation of an electric-field-induced permeability increase of the plasmalemma, which is usually explained by the creation and the growth of aqueous pores. For cells suspended in physiological buffers, the time domain of membrane charging is in the submicrosecond range. Systematic measurements using Nicotiana tabacum L.

Nanosecond electric pulses trigger actin responses in plant cells.

We have analyzed the cellular effects of nanosecond pulsed electrical fields on plant cells using fluorescently tagged marker lines in the tobacco cell line BY-2 and confocal laser scanning microscopy. We observe a disintegration of the cytoskeleton in the cell cortex, followed by contraction of actin filaments towards the nucleus, and disintegration of the nuclear envelope. These responses are accompanied by irreversible permeabilization of the plasma membrane manifest as uptake of Trypan Blue.