The role of actin in cell homeostasis

所有生物体的细胞都接收到必须作出反应的信号。对于细胞来说，协调不同的信号传导途径是很重要的，这样它们才能发挥正确的功能。我实验室的研究使用一个简单的单细胞生物作为模型系统。在这种细胞类型和哺乳动物等更复杂的生物细胞中，许多过程都以同样的方式发生。我们对一种叫做肌动蛋白的蛋白质的功能特别感兴趣。肌动蛋白是细胞骨架（意思是细胞骨架）结构的一部分，它帮助赋予细胞形状。然而，与人类骨骼不同的是，肌动蛋白是动态的，并且不断地重新排列。我们认为，这种动态特性允许肌动蛋白作为细胞环境的传感器来评估能量水平和细胞是否处于压力下。如果环境是好的，那么细胞过程可以继续进行。如果肌动蛋白由于能量低或被氧化剂修饰而不能发挥作用，它可能导致细胞进入细胞死亡途径。虽然这是一个基本的细胞生物学问题，但了解细胞如何应对压力会影响我们对衰老以及神经变性和癌症等疾病的理解。

Cells of all organisms receive signals that must be responded to. It is important for cells to co-ordinate different signalling pathways so they can perform their correct functions. Research in my laboratory uses a simple one-celled organism as a model system. Many processes are known to happen in the same way in this cell-type and in cells of more complex organisms such as mammals. We are particularly interested in the function of one protein called actin. Actin is part of a structure called the cytoskeleton (meaning cell skeleton) that helps give a cell its shape. Unlike a human skeleton however, actin is dynamic and constantly rearranging. We propose that this dynamic quality allows actin to act as a sensor of the cell environment to assess energy levels and whether the cell is under stress. If the environment is good, then cell processes can go ahead. If actin cannot function due to low energy or because it is modified by oxidants it can cause cells to enter a cell death pathway. While this is a fundamental cell biology problem, knowing how cells respond to stress impacts on our understanding of ageing and on disorders including neurodegeneration and cancer.