Chardès Claire, Clement Raphael, Blanc Olivier, Lenne Pierre-François
CNRS, Institut de Biologie du Développement de Marseille, Aix-Marseille Université.
CNRS, Institut de Biologie du Développement de Marseille, Aix-Marseille Université;
J Vis Exp. 2018 Nov 2(141). doi: 10.3791/57900.
Morphogenesis requires coordination between genetic patterning and mechanical forces to robustly shape the cells and tissues. Hence, a challenge to understand morphogenetic processes is to directly measure cellular forces and mechanical properties in vivo during embryogenesis. Here, we present a setup of optical tweezers coupled to a light sheet microscope, which allows to directly apply forces on cell-cell contacts of the early Drosophila embryo, while imaging at a speed of several frames per second. This technique has the advantage that it does not require the injection of beads into the embryo, usually used as intermediate probes on which optical forces are exerted. We detail step by step the implementation of the setup, and propose tools to extract mechanical information from the experiments. By monitoring the displacements of cell-cell contacts in real time, one can perform tension measurements and investigate cell contacts' rheology.
形态发生需要遗传模式和机械力之间的协调，以稳健地塑造细胞和组织。因此，理解形态发生过程的一个挑战是在胚胎发育过程中直接测量体内的细胞力和机械特性。在这里，我们展示了一种与光片显微镜耦合的光镊装置，它可以在以每秒几帧的速度成像的同时，直接对早期果蝇胚胎的细胞间接触施加力。该技术的优点是不需要将通常用作施加光力的中间探针的珠子注射到胚胎中。我们逐步详细介绍了该装置的实现，并提出了从实验中提取机械信息的工具。通过实时监测细胞间接触的位移，可以进行张力测量并研究细胞接触的流变学。
