高,细胞质中大量的钙离子结合蛋白得以激活。在植物中已发现多种钙离子结合 蛋白,其中包括钙调素和钙依赖型蛋白激酶。钙离子与钙调蛋白结合后形成的复 合物通过结合并激活它的靶蛋白将信息进行传导。随着钙离子通道的开放,钙离 子沿着电化学梯度迅速内流很快就会耗尽胞内和胞外钙库。为了信号传导的继 续,钙离子的储存必须通过依赖钙离子泵的主动运输重新建立。 Cytosolic calcium, [Ca2+] is one of the most important second messengers in plant cell signal transduction. The plant signals thought to be transduced through [Ca2+ include red light, blue light, temperature, touch, wind, gravity, hormones, fungal elicitors, and mineral nutrition. The resting concentrations of cytosolic Ca2+ is around 10-7-10-6mol L-1. The cell wall, vacuole and rough ER constitute large stores of Ca2+ with concentrations typically four to five orders of magnitude higher than cytosal levels. Calcium channels and calcium pumps embedded in the plasma membrane and membrane of ER and vacuole. Numerous Ca2+-binding proteins in the cytosal are thus activated by temporary increases in intracellular calcium concentration through the opening of these calcium channels. A number of Ca2+- binding proteins have been identified in plants including calmodulin and Ca2+-dependent calmodulin-like domain protein kinases(CDPKs). The Ca2-+/calmodulin complex transduces the Ca2+ signal by binding to and activating target proteins. With the opening of calcium channels, the immediate influx of Ca2+ down its electrochemical gradient can rapidly exhaust extracellular and intracellular stores. Before signal transduction can continue, intracellular stores of calcium must be reestablished through ATP-dependent active transport 叶绿信 ATP CaN+ ATP 冠 ※ H 细质藕 钙调素 钙调素是在动植物细胞中都能表达的钙离子结合蛋白。它能结合和调节很多种不 同的靶蛋白,从而参与多种不同的细胞活动的调节。钙调素有四个钙离子结合位 点。与钙离子结合后,钙调素发生构像改变,使得富含蛋氨酸,亮氨酸,苯丙氨高，细胞质中大量的钙离子结合蛋白得以激活。在植物中已发现多种钙离子结合 蛋白，其中包括钙调素和钙依赖型蛋白激酶。钙离子与钙调蛋白结合后形成的复 合物通过结合并激活它的靶蛋白将信息进行传导。随着钙离子通道的开放，钙离 子沿着电化学梯度迅速内流很快就会耗尽胞内和胞外钙库。为了信号传导的继 续，钙离子的储存必须通过依赖钙离子泵的主动运输重新建立。 Cytosolic calcium, [Ca2+] is one of the most important second messengers in plant cell signal transduction. The plant signals thought to be transduced through [Ca2+] include red light, blue light，temperature，touch, wind, gravity, hormones、 fungal elicitors, and mineral nutrition. The resting concentrations of cytosolic Ca2+ is around 10-7～10-6mol·L-1. The cell wall, vacuole and rough ER constitute large stores of Ca2+ with concentrations typically four to five orders of magnitude higher than cytosal levels. Calcium channels and calcium pumps embedded in the plasma membrane, and membrane of ER and vacuole. Numerous Ca2+-binding proteins in the cytosal are thus activated by temporary increases in intracellular calcium concentration through the opening of these calcium channels. A number of Ca2+- binding proteins have been identified in plants including calmodulin and Ca2+-dependent calmodulin-like domain protein kinases (CDPKs). The Ca2+/calmodulin complex transduces the Ca2+ signal by binding to and activating target proteins. With the opening of calcium channels, the immediate influx of Ca2+ down its electrochemical gradient can rapidly exhaust extracellular and intracellular stores. Before signal transduction can continue, intracellular stores of calcium must be reestablished through ATP-dependent active transport. 钙调素 钙调素是在动植物细胞中都能表达的钙离子结合蛋白。它能结合和调节很多种不 同的靶蛋白，从而参与多种不同的细胞活动的调节。钙调素有四个钙离子结合位 点。与钙离子结合后，钙调素发生构像改变，使得富含蛋氨酸，亮氨酸，苯丙氨