Class VI myosin moves processively along actin filaments backward with large steps
Class VI myosin moves processively along actin filaments backward with large steps
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DOI：
10.1006/bbrc.2001.6142
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发表时间：
2002-01-11
影响因子：
3.1
通讯作者：
Ikebe, M
中科院分区：
文献类型：
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作者：
Nishikawa, S;Homma, K;Ikebe, M
在肌球蛋白超家族中，VI类肌球蛋白使肌动蛋白丝向后移动。我们发现肌球蛋白VI在肌动蛋白丝上以大的（类似于36 nm）步长向后移动，然而它有一个极短的颈区。肌球蛋白V也以大的（类似于36 nm）步长向前移动，并且据信肌球蛋白V以其伸长的颈部结构域沿着肌动蛋白螺旋重复序列跨越，这对于肌球蛋白V以大步长向前移动是至关重要的。短颈肌球蛋白VI不能承受这种情况。我们通过电子显微镜发现，在ATP存在下，肌球蛋白VI以类似于36 nm的间隔与肌动蛋白丝协同结合，提出了一个假设，即肌球蛋白VI的结合引起肌动蛋白丝上的“热点”，吸引肌球蛋白头。肌球蛋白VI可以踩在肌动蛋白丝上的这些“热点”上，从而产生36 nm步长的进行性运动。(C)2002年，Elsevier Science。
Among a superfamily of myosin, class VI myosin moves actin filaments backwards. Here we show that myosin VI moves processively on actin filaments backwards with large (similar to36 nm) steps, nevertheless it has an extremely short neck domain. Myosin V also moves processively with large (similar to36 nm) steps and it is believed that myosin V strides along the actin helical repeat with its elongated neck domain that is critical for its processive movement with large steps. Myosin VI having a short neck cannot take this scenario. We found by electron microscopy that myosin VI cooperatively binds to an actin filament at similar to36 nm intervals in the presence of ATP, raising a hypothesis that the binding of myosin VI evokes "hot spots" on actin filaments that attract myosin heads. Myosin VI may step on these "hot spots" on actin filaments in every helical pitch, thus producing processive movement with 36 nm steps. (C) 2002 Elsevier Science.