Identification and disruption of a plant shaker-like outward channel involved in K+ release into the xylem sap

Gaymard F., Pilot Gérarld, Lacombe Benoit, Bouchez D., Bruneau Denis, Boucherez J., Michaux-Ferrière Nicole, Thibaud Jean-Baptiste, Sentenac Hervé. 1998. Identification and disruption of a plant shaker-like outward channel involved in K+ release into the xylem sap. Cell, 94 : 647-655.

Autre titre : Identification et rupture chez les végétaux d'un canal sortant de type shaker qui est impliqué dans le largage d'ions K+ dans la sève du xylem

Résumé : SKOR, a K+ channel identified in Arabidopsis, displays the typical hydrophobic core of the Shaker channel superfamily, a cyclic nucleotide-binding domain, and an ankyrin domain. Expression in Xenopus oocytes identified SKOR as the first member of the Shaker family in plants to be endowed with outwardly rectifying properties. SKOR expression is localized in root stelar tissues. A knockout mutant shows both lower shoot K+ content and lower xylem sap K+ concentration, indicating that SKOR is involved in K+ release into the xylem sap toward the shoots. SKOR expression is strongly inhibited by the stress phytolhormone abscisic acid, supporting the hypothesis that control of K+ translocation toward the shoots is part of the plant response to water stress.

Mots-clés Agrovoc : Arabidopsis, canal intercellulaire, échange d'ion, structure cellulaire, xylème, cation, potassium, racine

Classification Agris : F60 - Physiologie et biochimie végétale

Auteurs et affiliations

• Gaymard F.
• Pilot Gérarld
• Lacombe Benoit
• Bouchez D.
• Bruneau Denis
• Boucherez J.
• Michaux-Ferrière Nicole, CIRAD-AMIS-BIOTROP (FRA)
• Thibaud Jean-Baptiste
• Sentenac Hervé

Source : Cirad - Agritrop (https://agritrop.cirad.fr/401204/)

Métriques

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