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. 1992 Nov;100(3):1137–1141. doi: 10.1104/pp.100.3.1137

Characterization of Vacuolar Malate and K+ Channels under Physiological Conditions 1

Omar Pantoja 1,2,2, Angie Gelli 1,2, Eduardo Blumwald 1,2
PMCID: PMC1075757  PMID: 16653096

Abstract

Patch-clamp techniques were employed to study the electrical properties of vacuoles from sugar beet (Beta vulgaris) cell suspensions at physiological concentrations of cytoplasmic Ca2+. Vacuoles exposed to K+ malate revealed the activation of instantaneous and time-dependent outward currents by positive membrane potentials. Negative potentials induced only instantaneous inward currents. The time-dependent outward currents were 10 times more selective for malate than for K+ and were completely blocked by zinc. Vacuoles exposed to KCl developed instantaneous currents when polarized to positive or negative membrane potentials. The time-dependent outward channels could serve as the route for the movement of malate into the vacuole, whereas K+ could move through the time-independent inward and outward channels.

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Selected References

These references are in PubMed. This may not be the complete list of references from this article.

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