De Michelis M. I., Rasi-Caldogno F., Pugliarello M. C., Olivari C.
Istituto Botanico, Universita di Genova, corso Dogali 1/C, 16136 Genova, Italy (M.I.D.M.).
Plant Physiol. 1996 Mar;110(3):957-964. doi: 10.1104/pp.110.3.957.
A radioimmunoassay using antibodies raised against bovine serum albumin-conjugated fusicoccin (FC) was applied to measure FC bound to the plasma membrane (PM) isolated from seedlings of radish (Raphanus sativus L.) and of Arabidopsis thaliana treated in vivo plus or minus the toxin. FC bound to the PM from seedlings treated with 5 [mu]M FC was 2-fold (radish) to 7-fold (A. thaliana) higher than the binding capacity of control PM. FC binding depended on the duration of the in vivo treatment but was unaffected by cycloheximide. When FC binding and the PM H+-ATPase activity were compared under different conditions (in vivo or in vitro treatment of different lengths or with different concentrations of FC), a strict linear relation between FC binding and the activation of the PM H+-ATPase was observed in both plant materials under all the conditions tested. Comparison between the maximum binding capacity and the amount of H+-ATPase observed in PM from the two plant materials suggest a one-to-one stoichiometry between the FC receptor and the PM H+-ATPase.
使用针对牛血清白蛋白偶联的壳梭孢菌素（FC）产生的抗体进行放射免疫测定，以测量与从萝卜（Raphanus sativus L.）和拟南芥幼苗体内处理过毒素（加或不加毒素）后分离的质膜（PM）结合的FC。与用5 μM FC处理的幼苗的质膜结合的FC比对照质膜的结合能力高2倍（萝卜）至7倍（拟南芥）。FC结合取决于体内处理的持续时间，但不受环己酰亚胺的影响。当在不同条件下（不同长度或不同浓度FC的体内或体外处理）比较FC结合和质膜H⁺-ATP酶活性时，在所有测试条件下，两种植物材料中均观察到FC结合与质膜H⁺-ATP酶激活之间存在严格的线性关系。两种植物材料的质膜中观察到的最大结合能力与H⁺-ATP酶量之间的比较表明，FC受体与质膜H⁺-ATP酶之间存在一对一的化学计量关系。
