Killich T, Plath P J, Hass E C, Xiang W, Bultmann H, Rensing L, Vicker M G
Department of Biology, University of Bremen. FRG.
Biosystems. 1994;33(2):75-87. doi: 10.1016/0303-2647(94)90048-5.
We present evidence for a mechanism of eukaryotic cell movement. The pseudopodial dynamics and shape of Dictyostelium discoideum amoebae were investigated using computer-supported video microscopy. An examination of the cell periphery by the novel method of serial circular maps revealed explicit, classical wave patterns, which indicate the existence of intrinsic intracellular oscillations. The patterns are generated by the transit of self-organized, super-positioned, harmonic modes of rotating oscillatory waves (ROWS). These waves are probably associated with the dynamics of intracellular actin polymerisation and depolymerisation. A Karhunen-Loève expansion was conducted on one cell during 10 min of locomotion using points each 10 degrees around the cell's boundary. The results show that only 2-3 modes are necessary to describe the most essential features of cell movement and shape. Based on this analysis, a wave model was developed, which accurately simulates the dynamics of cell movement and shape during this time. The model was tested by reconstructing the cell's dynamical form by means of the Karhunen-Loève transform. No difference was detected between this reconstruction and the actual cell outline. Although cell movement and shape have hitherto been viewed as random, our results demonstrate that ROWS determine the spatio-temporal expression of pseudopodia, and consequently govern cell shape and movement, non-randomly.
我们提供了真核细胞运动机制的证据。利用计算机辅助视频显微镜研究了盘基网柄菌变形虫的伪足动力学和形状。通过串行圆形图的新方法对细胞周边进行检查，发现了明确的经典波型，这表明存在内在的细胞内振荡。这些波型是由自组织、叠加的旋转振荡波（ROWS）的谐波模式的传播产生的。这些波可能与细胞内肌动蛋白聚合和解聚的动力学有关。在一个细胞运动的10分钟内，使用围绕细胞边界每10度的点进行了卡尔胡宁-勒夫展开。结果表明，仅用2 - 3种模式就足以描述细胞运动和形状的最基本特征。基于此分析，开发了一个波模型，该模型准确地模拟了这段时间内细胞运动和形状的动力学。通过卡尔胡宁-勒夫变换重建细胞的动态形态对该模型进行了测试。在这种重建与实际细胞轮廓之间未检测到差异。尽管迄今为止细胞运动和形状被视为随机的，但我们的结果表明，ROWS非随机地决定了伪足的时空表达，从而控制细胞形状和运动。
