Structure and function of chromatin remodelling ATPase's and their dysfunction in in human disease.

真核生物的基因组与组蛋白相关，形成一种称为染色质的DNA蛋白复合物。染色质结构的调控提供了真核生物调控DNA获取的一种手段。实现这一目标的一种方法涉及到一个大家庭分子运动蛋白的作用，即染色质重塑atp酶。电子显微镜的最新进展为获得这些运动蛋白如何与染色质相互作用的重要新见解提供了机会。在这个建议中，我们将应用先进的电子显微镜和图像处理以及其他互补技术来研究这些运动蛋白在重新配置染色质时如何改变形状。这将为调控基因获取的过程提供新的见解。最近发现，编码这些运动蛋白的基因在癌细胞中经常发生改变。我们注意到，这些改变反复发生在几个不同亚型运动蛋白的相似位置。在一些先天性疾病中也发现了相关的改变。因此，我们将系统地描述这些变化如何影响马达的工作方式，并确定马达活动的哪个阶段被阻断。我们还将产生细胞系，使我们能够研究编码运动蛋白的基因缺失与在癌症中观察到的重复改变之间的差异。我们将发现，当运动基因的改变拷贝被移除时，细胞是否能够正常运作。如果是这样的话，阻断改变的运动基因，让细胞继续使用它们通常保留的运动基因的正常拷贝，可能会提供一种治疗病人的方法。该提案将产生一个知识平台，从中可以设计出针对缺陷电机的新方法。

The genomes of eukaryotes are associated with histone proteins to form a DNA protein complex called chromatin. The regulation of chromatin structure provides one means by which eukaryotic organisms regulated access to DNA. One means by which this is achieved involves the action of an extended family molecular motor proteins, known as chromatin remodelling ATPases. Recent advances to electron microscopy provide an opportunity to gain major new insights into how these motor proteins interact with chromatin. In this proposal we will apply advanced electron microscopy and image processing together with other complementary techniques to study how the shape of these motor proteins changes as they act to reconfigure chromatin. This will provide new insight into the process by which access to genes is regulated. It has recently become apparent that the genes that encode these motor proteins are often altered in cancer cells. We have noticed that these alterations repeatedly occur at a similar position on several different subtypes of motor proteins. Related alterations are also detected in some congenital diseases. As a result, we will systematically characterise how these alterations affect the way the motors work and determine which stage in the motors activity is blocked. We will also generate cell lines that will enable us to study the difference in between the loss of genes that encode motor proteins and the repeated alterations that are observed in cancers. We will find out whether cells are able to function normally when an altered copy of the motor gene is removed. If this is the case, blocking the altered motor and letting the cells carry on using the normal copy of the motor gene they typically retain may provide a way of treating patients. The proposal will generate a platform of knowledge from which new ways to target the defective motors can be devised.