Analysis of cell division and tissue biogenesis in situ

对于一个受精卵成为一个人，或任何其他多细胞生物体，许多细胞分裂必须发生。 细胞分裂是细胞生长，复制其DNA，将副本放置在细胞的两端，并在中间收缩的一系列事件。 我们专注于了解细胞是如何被夹成两半的。 这项工作是通过一种叫做收缩环的结构来完成的，它像一个钱包一样运作，使用与驱动肌肉收缩相同的细胞化学物质。大多数关于细胞分裂的研究都是在早期胚胎、酵母和生长在玻璃或塑料上的培养细胞上进行的。通过这个项目，我们将努力了解像皮肤这样的完整组织内细胞分裂的特殊要求。我们在一种流行的实验室蠕虫体内使用了一个简单的系统：一种由3个细胞组成的单层组织，在几个小时内变成22个细胞。我们可以拍摄这些细胞分裂的影片，并测量细胞被一分为二时随着时间的推移的形状。我们将测量我们看到的形状变化，并将这些事件与其他细胞类型（如早期胚胎）中类似的细胞收缩进行比较。我们还可以从这个细胞层中去除特定蛋白质（细胞化学物质）的功能，并观察细胞分裂如何受到影响。 我们预计，在组织的背景下，细胞分裂将有不同的要求，比孤立的细胞和早期胚胎。因此，在这个项目中进行的工作将帮助我们了解我们体内细胞分裂的真正机制。

For a single fertilized egg to become a person, or any other multicellular organism, many cell divisions must occur. Cell division is the set of events by which a cell grows, copies its DNA, places the copies at two ends of the cell, and pinches in the middle. We are focused on understanding how the cell is pinched in half. This job is accomplished with a structure called the contractile ring, which operates like a purse string, using the same cellular chemicals that drive muscle contraction. Most of the work on cell division has been done with early embryos, yeasts and cultured cells that live on glass or plastic. With this project, we will work to understand the special requirements of cell division within an intact tissue like your skin. We are using a simple system inside a popular laboratory worm: a tissue composed of a single layer of just 3 cells, which become 22 cells over a few hours. We can make movies of these cells dividing and measure the shape of a cell over time as it is pinched in two. We will measure the shape changes we see and compare these events to the analogous cell pinching in other cell types like early embryos. We can also remove function of specific proteins (cellular chemicals) from this cell layer and see how cell division is affected. We expect that cell division in the context of a tissue will have different requirements than that in isolated cells and early embryos. Therefore, the work undertaken in this project will help us understand the true mechanism of cell division within our bodies.