Johnson L N, O'Reilly M
Laboratory of Molecular Biophysics, University of Oxford, UK.
Curr Opin Struct Biol. 1996 Dec;6(6):762-9. doi: 10.1016/s0959-440x(96)80005-4.
The two examples of phospho and dephospho proteins for which structural data were previously available (glycogen phosphorylase and isocitrate dehydrogenase) demonstrated two different mechanisms for control. In glycogen phosphorylase, activation by phosphorylation results in long-range allosteric changes. In isocitrate dehydrogenase, inhibition by phosphorylation is achieved by an electrostatic blocking mechanism with no conformational changes. During the past year, the structures of the phospho and dephospho forms of two more proteins, the cell cycle protein kinase CDK2 and yeast glycogen phosphorylase, have been determined. The new results highlight the importance of the phosphoamino acids both in the organization of local regions of protein structure through phosphate-arginine interactions and in the promotion of long-range conformational responses.
先前已有结构数据的磷酸化和去磷酸化蛋白的两个例子（糖原磷酸化酶和异柠檬酸脱氢酶）展示了两种不同的调控机制。在糖原磷酸化酶中，磷酸化激活导致长程别构变化。在异柠檬酸脱氢酶中，磷酸化抑制是通过静电阻断机制实现的，没有构象变化。在过去的一年里，又有两种蛋白——细胞周期蛋白激酶CDK2和酵母糖原磷酸化酶的磷酸化和去磷酸化形式的结构被确定。新的结果突出了磷酸化氨基酸在通过磷酸-精氨酸相互作用组织蛋白质结构的局部区域以及促进长程构象反应方面的重要性。
