Reconstitution of an electrogenic auxin transport activity mediated by Arabidopsis thaliana plasma membrane proteins

FEBS Letters

Gibrat, Rémy¹  Espuna, Meriam¹  Szponarski, Wojciech¹  Doumas, Patrick¹  Guibal, Olivier¹  Rossignol, Michel¹ 

[1] Biochimie et Physiologie Moléculaire des Plantes, INRA/ENSA-M/CNRS URA 2133, place Viala, 34060 Montpellier Cedex, France

关键词: Auxin transport;    Efflux carrier;    Plasma membrane;    Protein reconstitution;    Diffusion potential;    Fluorescent probe;    Arabidopsis thaliana;    ETH;    N;    N′-diheptyl-N;    N′;    5;    5-tetramethyl-3;    7-dioxanonanediamide;    IAA;    indole-3-acetic acid;    ICA;    indole-3-carboxylic acid;    NPA;    naphtylphthalamic acid;   

DOI  :  10.1016/S0014-5793(99)00200-8

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

Plasma membrane proteins from Arabidopsis thaliana leaves were reconstituted into proteoliposomes and a K⁺ diffusion potential was generated. The resulting ionic fluxes, determined in the presence of the plant hormone auxin (indole-3 acetic acid), showed an additional electrogenic and saturable component, with a K _M of 6 μM. This flux was neither detected in liposomes in the presence of indole-3 acetic acid, nor in proteoliposomes in the presence of an inactive auxin analog and was completely inhibited by 3 μM naphtylphthalamic acid, a specific inhibitor of the auxin efflux carrier. The efficiency of the reconstituted carrier and the mechanism of its regulation by naphtylphthalamic acid are discussed.

【 授权许可】

Unknown