Multiple snapshots of the dynamics of supramolecular systems

(1)多镜头脉冲激光显微镜一个显微镜系统已经开发出来，允许顺序捕获的四个图像由微秒间隔。该系统是基于一个多帧条纹相机和多拍脉冲激光。(2)细胞电穿孔和细胞电变形在上述脉冲激光作用下，研究了海胆卵和巨脂质体的电穿孔。主要的发现是膜电导局部增加了10 S/cm ^2，电池阳极和阴极之间的电导明显不对称。我们还发现，细胞和脂质体在电场下变形，其方向取决于细胞内和细胞外电导的比例。(3)多视图显微镜已经开发了一种简单的设备，其允许投影不同种类的显微图像（例如，透射和荧光、不同波长的荧光、荧光的偏振分量）。(4)分子取向的测定利用上述（3），测定了肌动蛋白单体和肌动蛋白丝的取向.与肌球蛋白相互作用后的方向变化被发现是小的。通过将微丝中荧光团的数目减少到一个或两个，我们已经能够定量地检测滑动肌动蛋白丝的轴向旋转。(5)受精过程的分析使用（3），在卵子或精子中的多个受精过程中，形态学、细胞内钙浓度、细胞内pH、突起形成（卵子微绒毛或精子顶体）的变化在空间和时间上相关。

(1) Multi-shot pulsed laser microscopeA microscope system has been developed that allows sequential capturing of four images separated by microsecond intervals. The system is based on a multi-frame streak camera and a multi-shot pulsed laser.(2) Cell electroporation and cell electrodeformationUnder the pulsed laser above, electroporation of sea urchin eggs and of giant liposomes was investigated. The major findings were a localized increase in the membrane conductance in the order of 10 S/cm^2, and a marked asymmetry in the conductance between the anode and cathode sides of the cell. We have also found that cells and liposomes are deformed under an electric field and that its direction depends on the ratio of the intracellular and extracellular conductances.(3) Multiview microscopyA simple device has been developed that allows projection of differnt kinds of microscopic images (e.g., transmission and fluorescence, fluorescence at different wavelengths, polarized components of fluorescence) on a single video camera simultaneously and continuously.(4) Measurements of molecular orientationsUsing (3) above, orientations of actin monomers in and actin filament were determined. The change in orientation upon interaction with myosin was found to be small. By decreasing the number of fluorophores in a filament to one or two, we have been able to detect quantitatively the aial rotation of a sliding actin filament.(5) Analysis of fertilization processesUsing (3), multiple fertilization processes in an egg or sperm, the changes in morphology, intracellular calcium concentration, intracellular pH,protrusion formation (egg microvilli or sperm acrosome) have been correlated spatially and temporally.