PRESSURE-JUMP STUDIES ON THE LENGTH-REGULATION KINETICS OF THE SELF-ASSEMBLY OF MYOSIN FROM VERTEBRATE SKELETAL-MUSCLE INTO THICK FILAMENT
PRESSURE-JUMP STUDIES ON THE LENGTH-REGULATION KINETICS OF THE SELF-ASSEMBLY OF MYOSIN FROM VERTEBRATE SKELETAL-MUSCLE INTO THICK FILAMENT
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DOI：
10.1042/bj1970309
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发表时间：
1981-01-01
影响因子：
4.1
通讯作者：
DAVIS, JS
中科院分区：
文献类型：
--
作者：
DAVIS, JS
兔肌球蛋白单体通过两步机制自组装成粗丝。首先，一对肌球蛋白单体反应形成平行二聚体；二聚体又以与细丝长度无关的速率添加到细丝末端。另一方面，解离反应的速率取决于长度。当长丝从裸露区长到其全长时，解离速率常数呈指数增加 500 倍。因此，灯丝的长度受到动力学控制；肌球蛋白以固定速率添加到丝中，而解离速率增加到建立平衡并且丝停止生长的点。讨论了该机制中隐含的结构含义。
The self-assembly of rabbit myosin monomer into thick filament occurs via a 2-step mechanism. At 1st a pair of myosin monomers reacts to form a parallel dimer; the dimer in turn adds to the filament ends at a rate that is independent of filament length. The rate of the dissociation reaction on the other hand is length-dependent. The off rate constant increased exponentially by a factor of 500 as the filament grows from the bare-zone out to its full length. The length of the filament is thus kinetically controlled; myosin is added to the filament at a fixed rate, whereas the dissociation rate increases to a point where equilibrium is established and the filament ceases to grow. The structural implications implicit in the mechanism are discussed.