Input-output relationship in galvanotactic response of Dictyostelium cells
Input-output relationship in galvanotactic response of Dictyostelium cells
复制标题
竹荪细胞振荡响应中的输入输出关系
DOI：
10.1016/j.biosystems.2006.06.008
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发表时间：
2007-04-01
期刊：
影响因子：
1.6
通讯作者：
Ueda, Masahiro
中科院分区：
文献类型：
--
作者：
Sato, Masayuki J.;Ueda, Michihito;Ueda, Masahiro
在直流电场作用下，盘状骨细胞向阴极迁移。为了确定细胞电激反应的输入-输出关系，我们开发了一种实验仪器，该仪器可以高度再现施加于细胞的电信号，并定量分析运动反应。在没有电场的情况下，细胞向各个方向随机移动。在施加电场时，细胞的迁移速度比没有电场时快1.3倍左右。在0.25至10 V/cm的电场强度下，观察到电场对细胞迁移的动力学效应。细胞迁移方向随场强正方向向阴极倾斜，呈现出剂量依赖性的电激反应。对电场强度与定向运动关系的定量分析表明，细胞的偏态运动取决于电场强度的平方，这可以用一个简单的现象学方程来描述。趋流的阈值强度在0.25 ~ 1 V/cm之间。流控效率在2.6 V/cm时达到一半最大值，对应于10 μ m宽的圆形电池的阴极和阳极方向之间约8 mV的电压差。在此基础上，讨论了盘齿柱细胞趋流的可能机制。这一实验系统的发展，加上其对细胞内信号分子的良好微观可及性，使得盘基骨柱细胞作为一种模式生物有吸引力，用于阐明负责细胞运动及其调节的信号系统中的随机过程。2006爱思唯尔爱尔兰有限公司版权所有。
Under a direct current electric field, Dictyostelium cells exhibit migration towards the cathode. To determine the input-output relationship of the cell's galvanotactic response, we developed an experimental instrument in which electric signals applied to the cells are highly reproducible and the motile response are analyzed quantitatively. With no electric field, the cells moved randomly in all directions. Upon applying an electric field, cell migration speeds became about 1.3 times faster than those in the absence of an electric field. Such kinetic effects of electric fields on the migration were observed for cells stimulated between 0.25 and 10 V/cm of the field strength. The directions of cell migrations were biased toward the cathode in a positive manner with field strength, showing galvanotactic response in a dose-dependent manner. Quantitative analysis of the relationship between field strengths and directional movements revealed that the biased movements of the cells depend on the square of electric field strength, which can be described by one simple phenomenological equation. The threshold strength for the galvanotaxis was between 0.25 and I V/cm. Galvanotactic efficiency reached to half-maximum at 2.6 V/cm, which corresponds to an approximate 8 mV voltage difference between the cathode and anode direction of 10 mu m wide, round cells. Based on these results, possible mechanisms of galvanotaxis in Dictyostelium cells were discussed. This development of experimental system, together with its good microscopic accessibility for intracellular signaling molecules, makes Dictyostelium cells attractive as a model organism for elucidating stochastic processes in the signaling systems responsible for cell motility and its regulations. (c) 2006 Elsevier Ireland Ltd. All rights reserved.