Understanding the contribution of inositol phosphate signalling to class-1 HDAC complex function

“组蛋白去乙酰化酶”（HDAC）存在于身体的所有细胞中。它们的功能是关闭基因，并确保它们保持“关闭”状态。在很多方面，关闭一个基因和打开一个基因一样重要。HDAC酶代表了一个令人兴奋的医疗机会，因为它们是“可药物化的”。抑制HDAC活性的药物已经被用作临床抗癌药物，并在实验室中用于治疗痴呆和抗炎的有益作用。因此，有一个令人信服的应用，以及学术动机，研究他们的生理作用，以评估其潜在的药理学靶点。我们使用一种叫做“x射线晶体学”的技术，它使我们能够在分子水平上确定HDAC酶的形状和结构。一旦我们确定了它们的形状，就可以让我们了解hdac与其他蛋白质和小分子（如肌醇磷酸（IP））结合的方式。我们最近在体外（即在试管中）表明，hdac的酶活性依赖于IP的结合。根据这一发现，本项目的目的是了解IP对细胞和小鼠中HDAC功能的重要性。为此，我们有三个主要目标：1)我们计划生成具有低、中、高水平IP的细胞，并测试这些细胞是否与HDAC活性水平相关。2)在细胞中，hdac与其他蛋白质相互作用形成多蛋白质“复合物”。对IP最敏感的复合体称为MIDAC，它由三种结合在一起的蛋白质（HDAC1， DNTTIP1和MIDEAS）组成。为了了解IP对HDAC配合物的调控，我们计划用x射线晶体学来解决MIDAC的结构。3) MIDAC在细胞中的作用是完全未知的，因此我们的目的是表征MIDAC的生理活性，使用缺乏该复合体三成员之一的细胞，DNTTIP1。通过了解HDAC复合物功能的分子基础，我们可以利用这些知识来设计新的药物来防止它们起作用。阻止hdac发挥作用的能力对包括癫痫、双相情感障碍和阿尔茨海默病在内的许多疾病都有有益的影响，使它们成为很好的药物靶点。

'Histone deacetylase' (HDAC) enzymes are present in all cells of the body. Their function is to switch genes 'off', and make sure they stay 'off'. In many respects shutting a gene down is every bit as important as switching a gene on. HDAC enzymes represent an exciting medical opportunity because they are 'druggable'. Already, drugs which inhibit HDAC activity are being used in the clinic as anti-cancer agents, and in the laboratory for their beneficial effects on dementia and anti-inflammatory properties. There is therefore a compelling applied, as well as academic, motivation for studying their physiological roles in order to assess their potential as pharmacological targets. We use a technique called 'X-ray crystallography' which allows us to determine the shape and structure of HDAC enzymes at a molecular level. Once we have determined their shape it allows us to understand the way that HDACs bind to other proteins and small molecules such as inositol phosphate (IP). We recently showed in vitro (i.e. in a test tube) that the enzymatic activity of HDACs was dependent upon the binding of IP. Following on from this discovery, the purpose of this project is to understand the importance of IP to HDAC function in cells and in mice. To do this we have three main objectives: 1) We plan to generate cells with low, medium and high levels of IP and test whether these correlate with level of HDAC activity. 2) In cells, HDACs interact with other proteins to form a multi-protein 'complex'. The complex most sensitive to the presence of IP is called, MIDAC and it consists of three proteins bound together (HDAC1, DNTTIP1 and MIDEAS). To understand the regulation of HDAC complexes by IP we plan to solve the structure of MIDAC using X-ray crystallography. 3) The role of MIDAC in cells is completely unknown and so we aim characterize the physiological activity of MIDAC, using cells lacking one of the three members of the complex, DNTTIP1. By understanding the molecular basis of HDAC complex function we can use that knowledge to design new drugs to prevent them from working. The ability to stop HDACs from working has beneficial effects on a wide-range of diseases, including epiplepsy, bipolar dissorder and Alzheimer's disease, making them excellent drug targets.