Cell motility within a cell mass

我们目前研究的长期目标是了解细胞在三维多细胞团块中运动的机制。这种运动比一个孤立的细胞在平面基质上的迁移要复杂得多，因为团块内的细胞必须相互获得牵引力，并且在团块内部和通过团块时也要为自己扫清道路。我们使用延时3D显微镜研究这种“3D细胞运动”，这使我们能够在很长一段时间内观察活体标本的运动。目前的研究主要集中在肌球蛋白II分子在模式生物盘基骨菌的多细胞团体内的细胞运动中的作用。使用gfp标记的肌凝蛋白II，我们已经证明细胞后部的收缩伴随着细胞后部肌凝蛋白的特征重新分布。我们还表明，当检查某些肌凝蛋白突变体时，这种肌凝蛋白的重新分布是异常的，并且后缩回也随之受到影响。这些结果首次证明了肌球蛋白II在细胞后缩回中的特定功能作用。

The long term objective of our current research is to understand the mechanisms by which cells move within a three-dimensional, multicellular mass. This movement is more complex than migration of an isolated cell on a flat substrate, because cells within a mass must gain traction on each other and also clear paths for themselves within and through the cell mass. We study such "3D cell motion" using time-lapse 3D microscopy which permits us to observe locomotion in living specimens over extended time periods. Current research focuses on the role of the myosin II molecule in cell motility within the multicellular mass of the model organism Dictyostelium. Using a GFP-tagged mysoin II, we have shown that retraction of the cell rear is accompanied by a characteristic redistribution of the myosin at the cell rear. We have also shown that that this redistribution of myosin is abberant when certain myosin mutants are examined, and that rear retraction is also concomitantly affected. These results are the first to demonstrate a specific functional role for myosin II in rear retraction of a cell.