Single cell wound generates electric current circuit and cell membrane potential variations that requires calcium influx

Abstract

Breaching of the cell membrane is one of the earliest and most common causes of cell injury, tissue damage, and disease. If the compromise in cell membrane is not repaired quickly, irreversible cell damage, cell death and defective organ functions will result. It is therefore fundamentally important to efficiently repair damage to the cell membrane. While the molecular aspects of single cell wound healing are starting to be deciphered, its bio-physical counterpart has been poorly investigated. Using Xenopus laevis oocytes as a model for single cell wound healing, we describe the temporal and spatial dynamics of the wound electric current circuitry and the temporal dynamics of cell membrane potential variation. In addition, we show the role of calcium influx in controlling electric current circuitry and cell membrane potential variations. (i) Upon wounding a single cell: an inward electric current appears at the wound center while an outward electric current is observed at its sides, illustrating the wound electric current circuitry; the cell membrane is depolarized; calcium flows into the cell. (ii) During cell membrane re-sealing: the wound center current density is maintained for a few minutes before decreasing; the cell membrane gradually re-polarizes; calcium flow into the cell drops. (iii) In conclusion, calcium influx is required for the formation and maintenance of the wound electric current circuitry, for cell membrane re-polarization and for wound healing.