Ion channels in plants.

  title={Ion channels in plants.},
  author={Rainer Hedrich},
  journal={Physiological reviews},
  volume={92 4},
  • R. Hedrich
  • Published 1 October 2012
  • Biology
  • Physiological reviews
Since the first recordings of single potassium channel activities in the plasma membrane of guard cells more than 25 years ago, patch-clamp studies discovered a variety of ion channels in all cell types and plant species under inspection. Their properties differed in a cell type- and cell membrane-dependent manner. Guard cells, for which the existence of plant potassium channels was initially documented, advanced to a versatile model system for studying plant ion channel structure, function… 

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The plant vacuole plays a fundamental role in cell homeostasis. The successful application of patch-clamp technique on isolated vacuoles allows the determination of the functional characteristics of

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Results indicate that the cytosolic C-terminus is involved in the voltage-dependent gating mechanism of QUAC1, which regulates voltage dependencies and activation–deactivation kinetics in anion transporters in plants.

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The Arabidopsis guard cell outward potassium channel GORK is regulated by CPK33

A functional screen in Xenopus oocytes was launched to identify CPKs able to regulate the three main guard cell Shaker channels KAT1, KAT2, and GORK and indicates that GORK activity is enhanced by CPK33 and unaffected by a nonfunctional CPK 33 (CPK33‐K102M).

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The finding that the rice TPC1, just like those from the model plant Arabidopsis and even animal cells, is localized and active in lyso-vacuolar membranes associates this cation channel species with endomembrane function.

The K+ channel KZM2 is involved in stomatal movement by modulating inward K+ currents in maize guard cells

The presented results demonstrate that KZM2 functions as a negative regulator to modulate the Kin channels in maize guard cells and may form heteromeric Kin channel and control stomatal opening in maize.

Tale of tail current.

    S. Kodirov
    Progress in biophysics and molecular biology
  • 2019

Update on Genetic Identities of Plant Calcium Channels Plant Calcium-Permeable Channels 1

The electrophysiological approach has seen a relatively small band of laboratories overcome the technical barriers presented by plant cells to reveal distribution and regulatory properties of plasma membrane and endomembrane channels.

Guard cells in fern stomata are connected by plasmodesmata, but control cytosolic Ca2+ levels autonomously.

The symplastic connections between f Fern guard cells in mature stomata indicate that the biophysical mechanisms that control stomatal movements differ between ferns and seed plants.

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Insight is provided into the current state of the plant ion channel field and new approaches with patch-clamping plant cells and transporters are introduced.

Inward rectifier potassium channels in plants differ from their animal counterparts in response to voltage and channel modulators

It is concluded that the inward rectification of the currents mediated by the KAT1 gene product, or the related endogenous channels of plant cells, results from voltage-modulated structural changes within the channel proteins.

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Distinct potassium, anion, and calcium channels in the plasma membrane and vacuolar membrane of plant cells have been identified and characterized by patch clamping. Primarily owing to advances in

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Structure and function of potassium channels in plants: some inferences about the molecular origin of inward rectification in KAT1 channels (Review)

It is proposed here that in plant-inward rectifiers an inward movement of S4 leads to channel opening and that the difference between it and outward-rectifying channels resides in the mechanism that couples gating charge displacement with pore opening.

Two types of anion channel currents in guard cells with distinct voltage regulation.

    J. SchroederB. Keller
    Proceedings of the National Academy of Sciences of the United States of America
  • 1992
It is shown here that two highly distinct types of depolarization-activated anion currents operate in the plasma membrane of Vicia faba guard cells, and it is hypothesized that S-type anion channels may provide a central molecular mechanism for control of stomatal closing, which is accompanied by long-term anion efflux anddepolarization.

Expression of an inward-rectifying potassium channel by the Arabidopsis KAT1 cDNA.

It is shown that a single messenger RNA transcript from the Arabidopsis thaliana KAT1 complementary DNA confers the functional expression of a hyperpolarization-activated K+ channel in Xenopus oocytes.

Cloning and electrophysiological analysis of KST1, an inward rectifying K+ channel expressed in potato guard cells.

The molecular cloning and characterization of a voltage‐dependent K+ channel (KST1) from potato guard cells and related studies on potato guard cell protoplasts confirmed the biophysical characteristics of the kst1 gene product (Kst1) in the heterologous expression system.

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A cation-selective channel was observed, which showed a high selectivity for K+, with a permeability ratio PK+/PNa+ of 11:1 and a single-channel conductance of 37 pS in symmetrical 225 mM KC1 solutions, which is estimated to contribute significantly to the uptake and release of K+ by guard cells during stomatal movement.