STRUCTURE & REGULATION OF TYPE 1 PROTEIN PHOSPHATASES

这项研究的总体目标是了解蛋白质的作用 激素信号转导机制中的磷酸酶。荷尔蒙 如肾上腺素和胰岛素通过以下方式引起其生理反应 改变细胞内关键调控蛋白的磷酸化状态 几乎可以肯定，磷蛋白和蛋白磷酸酶参与了 这些控件。这个项目研究的是蛋白质的主要类别之一 磷酸酶，1型磷酸酶，特别是两种特定的 称为ATP-镁依赖的磷酸酶和糖原结合的酶 磷酸酶。对这些酶的功能和调节的知识是 不完整。这两种酶似乎都是由多位点控制的。 它们的调节亚基的磷酸化。结构-功能研究 将旨在识别和理解个人的角色 磷酸化位点在两个调节之间的相互作用 监管和催化部件也将被寻求。方法将是 使用的包括定点突变和缺失突变。在……里面 此外，利用合成肽和特定的竞争研究 将使用抗体探针。荷尔蒙调节研究将是 受雇的。激素调节研究将利用横隔肌 系统和培养细胞，并将重点放在胰岛素和 肾上腺素。抑制物-2在哺乳动物培养细胞系中的表达 在个别磷酸化位点突变的G-亚基应该会有所帮助 探讨各部位的生理作用及其调节机制 荷尔蒙信号的传递。这次调查的成功将是 具有广泛的意义，因为这些磷酸酶被认为 调节多种代谢途径和其他细胞功能。

The overall objective of this research is to understand the role of protein phosphatases in the mechanisms of hormonal signal transduction. Hormones such as epinephrine and insulin elicit their physiological responses by altering the phosphorylation state of key regulatory intracellular phosphoproteins and protein phosphatases are almost certainly involved in these controls. This project addresses one of the main classes of protein phosphatases, the type 1 phosphatases, and in particular, two specific enzymes termed the ATP-Mg-dependent phosphatase and the glycogen-bound phosphatase. Knowledge of the function and regulation of these enzymes is incomplete. Both enzymes appear to be controlled by multisite phosphorylation of their regulatory subunits. Structure-function studies will be aimed at identifying and understanding the roles of the individual phosphorylation sites on the two regulatory for interactions between the regulatory and catalytic components will also be sought. Methods to be used include site-directed mutagenesis and deletion mutations. In addition, competition studies utilizing synthetic peptides and specific antibody probes will be employed. Hormonal regulation studies will be employed. Hormonal regulation studies will utilize diaphragm muscle systems and cultured cells and will focus on the action of insulin and epinephrine. Expression in mammalian cultured cell lines of inhibitor-2 and G-subunit mutated at the individual phosphorylation sites should help probe the physiological role of each site and the mechanisms mediating transmission of the hormone signals. Success in this investigation will be of widespread significance since these phosphatases are believed to regulate a variety of metabolic pathways and other cellular functions.