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. 1987 Jan;83(1):53–57. doi: 10.1104/pp.83.1.53

Voltage-Dependent K+-Channel in Protoplasmic Droplets of Chara corallina1

A Single Channel Patch Clamp Study

Fabrice Homblé 1,2,2, Jack M Ferrier 1,2, Jack Dainty 1,2
PMCID: PMC1056298  PMID: 16665215

Abstract

Passive transport of potassium through the plasma membrane of a protoplasmic droplet isolated from large internodal cells of Chara corallina Klein ex Willd., em, R.D.W. has been investigated using the patchclamp technique. When the membrane is hyperpolarized the conductance of a single K+-channel is of the order of magnitude of 100 picoSiemens and is reduced by tetraethylammonium chloride. Its open time is voltage dependent. This voltage-dependent K+-channel displays rectifying properties. The channel density is about 0.1 channel per square micrometer of membrane. When the membrane is depolarized the conductance of a single channel is of the order of magnitude of 30 picoSiemens and is insensitive to tetraethylammonium chloride. These results suggest that K+-channels are incorporated in the plasma membrane during membranogenesis of a protoplasmic droplet. They constitute further evidence for the existence of voltage-dependent K+-channels in plant cells.

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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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