REGULATION OF DICTYOSTELIUM MYOSIN BY PHOSPHORYLATION

通过磷酸化调节盘基网柄肌球蛋白

• 批准号: 2184055
• 负责人: James Spudich
• 金额: $ 22.63万
• 依托单位: STANFORD UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 1991
• 资助国家: 美国
• 起止时间: 1991-07-01 至 1996-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/2184055
• 关键词: Dictyostelium; adenosine triphosphate; biological signal transduction; cell cell interaction; cell cycle; cell motility; cytoskeleton; electroporation; enzyme mechanism; liquid chromatography; molecular genetics; morphology; myosins; nucleic acid sequence; phosphoprotein phosphatase; phosphorylation; polymerase chain reaction; protein biosynthesis; protein kinase; protein structure function

Interaction of the molecular motor myosin with actin drives muscle contraction and various changes in cell shape and movements that are fundamental to the biology of nonmuscle eukaryotic cells. Essential to the function of myosin in nonmuscle cells is the regulation of its assembly into filaments and higher order structures such as the contractile ring, the assembly of which is spatially and temporally controlled. Little is known about the molecular basis of such spatial and temporal control but phosphorylation of the myosin molecule appears to play a key role. Light chain phosphorylation may regulate myosin filament assembly in some systems, but may primarily control the motor function of myosin. Heavy chain phosphorylation may be primarily involved in regulation of myosin filament assembly. The specific aim of this proposal is to study the roles of myosin phosphorylation in Dictyostelium, an organism that allows the convergence of biochemical, molecular genetic, and physiological approaches. It therefore offers a unique opportunity to investigate the molecular basis of how a cell moves, divides, and changes shape in response to cellular and developmental signals. The experimental plan for the next five year period can be divided into three parts: 1. Biochemical, structural, and molecular genetic studies on the kinases and phosphatases that are responsible for the control of Dictyostelium myosin phosphorylations. 2. Biochemical and structural studies on the effects of these phosphorylations on the functions of purified myosin. 3. Characterization of the effects of phosphorylation on the in vivo behavior and function of the myosin. The latter is made possible by recent applications of sophisticated molecular genetic techniques to Dictyostelium.

分子运动肌球蛋白与肌动蛋白的相互作用驱动肌肉 收缩以及细胞形状和运动的各种变化 非肌肉真核细胞生物学的基础。必不可少的 非肌肉细胞中肌球蛋白的功能是调节其组装 分解成细丝和更高阶的结构，例如收缩环， 其组装在空间和时间上受到控制。小的是 已知这种空间和时间控制的分子基础，但是 肌球蛋白分子的磷酸化似乎起着关键作用。 光 链磷酸化可能调节某些肌球蛋白丝的组装 系统，但可能主要控制肌球蛋白的运动功能。 重的 链磷酸化可能主要参与肌球蛋白的调节 灯丝组件。 该提案的具体目的是研究角色 盘基网柄菌中肌球蛋白磷酸化的作用，盘基网柄菌是一种允许 生物化学、分子遗传学和生理学的融合 接近。 因此，它提供了一个独特的机会来调查 细胞如何移动、分裂和改变形状的分子基础 细胞和发育信号。 下一步的实验计划 五年时间可分为三个部分： 1. 激酶的生化、结构和分子遗传学研究 和负责控制盘基网柄菌的磷酸酶 肌球蛋白磷酸化。 2. 这些影响的生化和结构研究 磷酸化对纯化肌球蛋白功能的影响。 3. 磷酸化对体内影响的表征 肌球蛋白的行为和功能。 后者是通过最近复杂的应用而成为可能的 分子遗传学技术 盘基网柄菌。