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 磷酸酶在激素信号转导机制中的作用。 激素 例如肾上腺素和胰岛素引起它们生理反应， 改变细胞内关键调节因子的磷酸化状态 磷蛋白和蛋白磷酸酶几乎肯定参与了 这些控制。 该项目涉及蛋白质的主要类别之一 磷酸酶，1型磷酸酶，特别是两种特异性磷酸酶， 被称为ATP-Mg依赖性磷酸酶和糖原结合型磷酸酶的酶 磷酸酶。 这些酶的功能和调节的知识是 不完整 这两种酶似乎都受多位点控制， 其调节亚基的磷酸化。 结构-功能研究 将旨在确定和理解个人的角色 磷酸化位点上的两个调控之间的相互作用， 还将寻求监管和催化成分。 方法的 使用的突变包括定点诱变和缺失突变。 在 此外，利用合成肽和特异性 将使用抗体探针。 激素调节研究将是 就业。 激素调节研究将利用膈肌 系统和培养的细胞，并将重点放在胰岛素的作用， 肾上腺素 抑制因子-2在哺乳动物培养细胞系中的表达 在磷酸化位点发生突变的G亚基 探讨每个部位的生理作用和介导机制 激素信号的传递。 这次调查的成功 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.