Stored elastic energy powers the 60-microm extension of the Limulus polyphemus sperm actin bundle.
Stored elastic energy powers the 60-microm extension of the Limulus polyphemus sperm actin bundle.
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储存的弹性能量为鲎精子肌动蛋白束的 60 微米延伸提供动力。
DOI：
10.1083/jcb.200304006
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发表时间：
2003
期刊：
影响因子：
--
通讯作者：
Matsudaira,Paul
中科院分区：
文献类型：
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作者：
Shin,JenniferH;Mahadevan,L;Waller,GuillerminaS;Langsetmo,Knut;Matsudaira,Paul
在顶体反应的5秒内，一束60 μm长的肌动蛋白丝从卷曲的构象中拉直并从细胞中伸出。为了确定这种运动的动力，我们研究了化学和机械能的可能来源，并表明线圈释放了~ 10−13J的储存机械应变能，而钙结合产生的化学能为~ 10−15J。这些测量表明，卷曲的肌动蛋白束通过一种基于弹簧的机制延伸，这与众所周知的聚合或肌球蛋白驱动的过程明显不同，并且钙启动但不为反应提供动力。
During the 5 s of the acrosome reaction ofLimulus polyphemussperm, a 60-μm-long bundle of scruin-decorated actin filaments straightens from a coiled conformation and extends from the cell. To identify the motive force for this movement, we examined the possible sources of chemical and mechanical energy and show that the coil releases ∼10−13J of stored mechanical strain energy, whereas chemical energy derived from calcium binding is ∼10−15J. These measurements indicate that the coiled actin bundle extends by a spring-based mechanism, which is distinctly different from the better known polymerization or myosin-driven processes, and that calcium initiates but does not power the reaction.