REGULATION OF CYTOKINESIS IN BUDDING YEAST

胞质分裂是有丝分裂的关键步骤，是有丝分裂的基础 对于真核生物的生长和发展以及对 病理性疾病，如癌症。胞质分裂也是一个重要的 胚胎不对称的产生机制。因此，理解 胞质分裂的机制和调控可能具有广泛的医学意义。 这意味着什么。在动物细胞中，已知胞质分裂依赖于 基于肌动球蛋白的收缩环。我们的长期目标是了解 收缩环的组装和功能的时空调节。这 知识也可以促进对其他肌动球蛋白依赖细胞的研究 细胞移动和荷包伤口愈合等过程。我们有 最近在萌芽酵母中发现了一种基于肌动球蛋白的环结构，并 展示了它在胞质分裂过程中的关键作用。这一发现提供了一种 学习这一基本过程的独特机会结合使用 酵母菌的遗传、生化和视频显微镜方法。 具体地说，李博士将研究肌动蛋白和肌球蛋白II的机制 肌动球蛋白在收缩环组装过程中的定位调节 环的收缩，以及环的解体机制 收缩。第二个目标是了解胞质分裂是如何与 后期纺锤体动力学，因为这样的协调对 成功地将遗传物质分割到子代细胞。我们已经这么做了 发现了几种结构蛋白和信号蛋白，它们在 肌动球蛋白环的活性，以及可能是 对于胞质分裂与其他后期事件的协调很重要。我们 将进行进一步的遗传和生化分析以确定它们的 作用机制。因为这些蛋白质中的大多数都有哺乳动物的同源物， 我们的发现应该有助于在其他真核生物中研究类似的过程 有机体。

Cytokinesis is a crucial step in mitotic cell division which is the basis for the growth and development of eukaryotic organisms as well as for pathological conditions such as cancer. Cytokinesis is also an important mechanism for the generation of embryonic asymmetry. Therefore, understanding the mechanism and regulation of cytokinesis is likely to have broad medical implications. In animal cells, cytokinesis is known to be dependent on an actomyosin-based contractile ring. Our long term goal is to understand the spatial and temporal regulation of contratile ring assembly and function. This knowledge could also facilitate studies of other actomyosin-dependent cellular processes, such as cell locomotion and purse-string wound healing. We have recently identified an actomyosin-based ring structure in budding yeast and demonstrated its critical function during cyokinesis. This finding provides a unique opportunity for studyinh this fundamental process using a combination of genetic, biochemical and video microscopy approaches in yeast. Specifically, Dr. Li will investigate the mechanism of actin and myosin II localization during contractile ring assembly, the regulation of actomyosin ring contraction, as well as the mechanism of ring disassembly during contraction. A second goal is to understand how cytokinesis is coordinated with anaphase spindle dynamics, because such coordination is important for the successful partitioning of genetic material to progeny cells. We have already identified several structural and signaling proteins that play crucial roles in the actomyosin ring activities, and checkpoint proteins that are likely to be important for the coordination of cytokinesis with other anaphase events. We will carry out further genetic and biochemical analysis to determine their mechanism of function. Because most of these proteins have mammalian homologs, our findings should facilitate studies of similar processes in other eukaryotic organisms.