pH control of the plant outwardly‐rectifying potassium channel SKOR

FEBS Letters

Sentenac, Hervé¹  Pilot, Guillaume¹  Gaymard, Frédéric¹  Lacombe, Benoît¹  Thibaud, Jean-Baptiste¹ 

[1] Biochimie et Physiologie Moléculaire des Plantes, UMR 5004 Agro-M/CNRS/INRA/UM2, Place Viala, 34060 Montpellier Cedex 1, France

关键词: K+ channel;    pH;    Xenopus oocyte;    Patch clamp;    Arabidopsis thaliana;   

DOI  :  10.1016/S0014-5793(00)01093-0

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

SKOR, an Arabidopsis depolarisation-activated K⁺-selective channel, was expressed in Xenopus oocytes, and external and internal pH effects were analysed. Internal pH was manipulated by injections of alkaline or acidic solutions or by acid load from acetate-containing medium. An internal pH decrease from 7.4 to 7.2 induced a strong (ca. 80%) voltage-independent decrease of the macroscopic SKOR current, the macroscopic gating parameters and the single channel conductance remained unchanged. An external acidification from 7.4 to 6.4 had similar effects. It is proposed that pH changes regulate the number of channels available for activation. Sensitivity of SKOR activity to pH in the physiological range suggests that internal and external pH play a role in the regulation of K⁺ secretion into the xylem sap.

【 授权许可】

Unknown