Evidence for polyamine channels in protoplasts and vacuoles of Arabidopsis thaliana cells.

The presence of ion channels permeable to polyamines in the plasma membrane and tonoplast of Arabidopsis thaliana cultured cells was investigated by means of the patch-clamp technique in the whole-cell configuration. Evidence is shown for channels, activated by depolarizations in protoplasts and by hyperpolarizations in vacuoles, with slow time course of activation, permeable to putrescine, spermidine and spermine.