Puffing of aCSF alone never induced membrane voltage changes (data not shown).
The electrotonic coupling strength was assessed by the coupling coefficient (CC), defined as the ratio of membrane voltage changes between the postjunctional and prejunctional cells [9].
The input resistance was measured from the slope of the linear portion of the I/V relationship (Fig. 9B) obtained by plotting membrane voltage changes produced by steps of current (0.1 nA, 1s; Fig. 9A).
Since prestin is known to have both voltage-sensing and ion transporting capacities [20], [21], it may sense membrane voltage changes induced by kanamycin, a known ionophore allowing influx of cations [22], with conformational changes that facilitate anion transporting capacity of prestin.
These bound ions are responsible for ion channel opening and/or closing and thus for control of ion influx and efflux through the cell membrane, which leads to membrane voltage changes and specific proliferative response.
FRET-based GEVIs are stably expressed and well-tolerated by Arabidopsis and a recent study documents the successful use of Mermaid FRET sensors to monitor membrane voltage changes in response to exogenous application of potassium in a plant system [ 20].
