鉴定脱落酸结合蛋白的受体功能

The purpose of this project is focused on the indentification of ABA receptor by using the responses of protoplast and mitochondria to ABA as the model systems. With the experiments of barley alerone protoplasts, we found that ABA induced an increase of intracellular calcium concentration, but anti-ABA binding protein antibodies cannot block this process. The main reason is that the ABA-binding protein we used in the experiment doesn't work as cell membrane-bound ABA receptor. Alternatively, we studied the action of ABA in maize mitochondria instead, and found that ABA and its analogs (RCA7a & RCA7b) all induced the increase of membrane fluicity and NAD+-isocitrate dehydragenase (ICDH) activity. Furthermore, anti-ABA binding protein antibodies showed an great effect on blocking the increase of ICDH activity induced by ABA. Above results demonstrated that the ABA-binding protein we used has the property of intracellular ABA receptor located on mitochondria. We suggest that mitochondria could be an valuable subcellular system for the study of ABA signaling.

以大麦糊粉细胞原生质体对脱落酸的响应为模式系统，检测识别脱落酸结合蛋白的抗体和抗脱落酸单克隆抗体的独特型抗体，以及脱落酸结合蛋白对该系统中脱落酸效应的影响，鉴定脱落酸结合蛋白的受体功能，并探测大麦糊粉原生质体质膜上存在的脱落酸受体。本项目将为研究脱落酸信号的感受与转导提供有效的模式和方法，促进脱落酸作用机理的研究。