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. 1987 Jun;84(2):433–437. doi: 10.1104/pp.84.2.433

A Tight-Seal Whole Cell Study of the Voltage-Dependent Gating Mechanism of K+-Channels of Protoplasmic Droplets of Chara corallina1

Fabrice Homblé 1,2
PMCID: PMC1056597  PMID: 16665457

Abstract

The biophysical properties of voltage-dependent K+-channels of protoplasmic droplets of Chara corallina Klein ex Willd., em, R.D.W. were investigated using the tight-seal whole cell method. Two potassium currents were observed in voltage-clamp mode and they can be used to explain the transient membrane potential time course observed in current-clamp mode. The K+-channels are identified by the effect of tetraethylammonium chloride which blocks both currents. A two-state, constant dipole moment model is used to fit the voltage-conductance curve. From this model the minimum equivalent gating charge involved in the gating mechanism of K+-channels of Chara can be estimated.

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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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