Uchida G, Chinzei T, Matsuura H
Research Center for Advanced Science and Technology, University of Tokyo, Komaba 4-6-1, Meguro, Tokyo, 153-8904, Japan.
Biochem Biophys Res Commun. 1999 Apr 2;257(1):223-7. doi: 10.1006/bbrc.1999.0444.
We have visualized bundles of the actin filaments of a Characean internodal cell and investigated the sliding motion of organelles with myosin on the bundles. The investigation revealed that a power spectrum of the sliding velocity time series of the organelle has two remarkable peaks near 4 and 7.5 Hz. This suggests that myosin molecules attached to the organelle not independently but cooperatively produce the sliding force. Moreover, we have found that some organelles move in the opposite direction of their sliding motion for several hundred milliseconds along the bundles. The fluctuation analysis of that motion showed that a power spectrum profile of the reverse velocity time series almost agreed with that of the sliding velocity time series. This result suggests that the dynamics of the reverse motion is the same as that of the sliding motion.
我们已经观察到轮藻节间细胞中肌动蛋白丝束，并研究了细胞器在这些丝束上与肌球蛋白的滑动运动。研究揭示了细胞器滑动速度时间序列的功率谱在4赫兹和7.5赫兹附近有两个显著峰值。这表明附着在细胞器上的肌球蛋白分子不是独立产生而是协同产生滑动力。此外，我们发现一些细胞器会沿着丝束在其滑动运动的相反方向移动数百毫秒。对该运动的涨落分析表明，反向速度时间序列的功率谱轮廓与滑动速度时间序列的几乎一致。这一结果表明反向运动的动力学与滑动运动的动力学相同。
