ROLE OF PHOSPHORYLATION AS A REGULATORY MECHANISM IN MUSCLE CONTRACTION

依赖磷酸化的肌球蛋白连接的机制 对平滑肌和非肌肉肌球蛋白的调节正在进行 调查过了。这涉及几种方法：(1)测量 动力学循环中不同步骤的速率常数 蛋白水解剂重链肌球蛋白(HMM)对镁三磷酸腺苷的水解作用 肌球蛋白亚片段，在肌动蛋白存在和不存在的情况下； 以胞浆肌球蛋白和肌球蛋白为原料制备HMM 它们的动力学性质的表征，以及(3)In的使用 体外运动系统如何量化运动速度 肌球蛋白包衣微珠的稳定性受多种因素的影响。我们是 还研究了钙调蛋白的作用机制，一种可能的 与肌动蛋白细丝相关的调节蛋白。

The mechanism of the phosphorylation-dependent myosin-linked regulation of smooth muscle and nonmuscle myosins is being investigated. This involves several approaches: (1) measurement of rate constants for various steps in the kinetic cycle for the hydrolysis of MgATP by heavy meromyosin (HMM), the proteolytic subfragment of myosin, in the presence and absence of actin; (2) preparation of HMM from cytoplasmic myosins and characterization of their kinetic properties, and (3) use of an in vitro motility system to quantitate how the velocity of movement of myosin-coated beads is affected by various factors. We are also studying the mechanism of action of caldesmon, a possible regulatory protein associated with actin filaments.