CA2+-Mediated Signal Transduction in Plants

一个新的钙离子依赖性蛋白激酶家族，称为CDPKs， 最近被发现。 CDPK是独一无二的，因为它们有一个 具有连接到Ca2+结合的激酶结构域的新结构 类似于钙调素的结构域。 一个重要的长期目标是 了解CDPKs在Ca2+介导的信号中的功能 转导途径。 模式植物系统拟南芥已经被 为此目的而选择。 该提案的基础是， 确定Ca2+如何调节CDPK活性。 生物化学和 分子遗传学方法将用于测试一个模型， 被称为“CaMK II的流线型版本”。 大肠杆菌表达 已经开发了系统来为此提供功能酶 目的. 将采用两种方法来调查 特异性CDPK同种型的生物学功能：1）同种型AK1 和突变的"不受调控"的AK1，将过度表达， 在转基因植物中， 它在体内的活性。 2)AK1的细胞内定位将是 决心提供关于其体内潜力的信息 印刷受体.

A new family of Ca2+-dependent protein kinases, called CDPKs, has recently been discovered. CDPKs are unique because they have a novel structure with a kinase domain joined to a Ca2+-binding domain similar to calmodulin. An important long term goal is to understand the function of CDPKs in Ca2+-mediated signal transduction pathways. The model plant system Arabidopsis has been chosen for this purpose. The foundation of the proposal is to determine how Ca2+ regulates CDPK activity. A biochemical and molecular genetic approach will be used to test a model referred to as a "stream-lined version of CaMK II". An E. coli. expression system has been developed to provide functional enzyme for this purpose. Two approaches will be pursued to investigate the biological functions of a specific CDPK isoform: 1) Isoform AK1 and a mutant "unregulated" version of AK1, will be over-expressed in transgenic plants to examine the effects of altering the balance of its activity in vivo. 2) AK1's intracellular location will be determined to provide information on its potential in vivo substrates.