Hedgehog acyltransferase : structure and function in health and disease

研究蛋白质和酶等生物分子如何在原子水平上发挥作用的能力，是我们理解生命的关键--例如，单个受精的卵细胞如何产生像人类一样的复杂的多器官有机体--也是更快、更有效地开发针对这些生物分子的药物的关键。然而，某些类型的生物分子，例如存在于生物膜内的蛋白质(称为“膜蛋白”)，对现代分析方法提出了巨大的挑战。在这里，我们建议结合多种新的方法来研究一种名为Hedgehog acylTransfer ase(HHAT)的膜蛋白的结构和功能，HHAT是生长和发育的关键调节因子，也与某些成人癌症的发生有关。由此产生的对HHAT的分子水平的了解将使人们能够努力在治疗上针对HHAT，并指导未来对其他类似挑战的膜蛋白的研究。HHAT调节细胞之间相互通信的“Hedgehog信号通路”。Hedgehog途径是动物生长和发育的关键，并因其在果蝇中的发现而得名，在果蝇中，破坏会导致幼虫发育成像刺猬一样的尖峰外观。在健康的成年人中，刺猬信号通常是关闭的，但在某些癌症患者中，它会重新激活。我们的研究将使用三种不同的、但相互补充的方法来解决了解HHAT如何发挥作用以及这如何影响刺猬信号的问题。我们将使用化学生物学来创造HHAT修饰的分子的变体，这将使我们能够了解这些分子如何与HHAT相互作用。同时，我们将使用最先进的结构生物学方法，使我们能够在原子水平上可视化HHAT的三维结构。最后，我们将利用这些新的见解来了解HHAT如何在细胞中发挥作用，并设计新的HHAT蛋白质，这些蛋白质改变了他们修改的分子的偏好。这些新的设计者将被用来理解HHAT如何调节细胞之间的通信距离和程度。这项研究将提供对HHAT和Hedgehog信号在发育和癌症等疾病中的作用的基本了解，并提供一种重要的手段来调节设计的“合成”生物系统中的细胞间通信。它还将提供3D结构信息，并确定分子可以与HHAT结合的区域，这将极大地加快药物发现工作。此外，这项工作将提供一个路线图，以指导未来针对其他相关膜蛋白的研究，这些蛋白是一系列疾病的靶标。

The ability to study how biological molecules, such as proteins and enzymes, function on an atomic level is key to our understanding of life - for example, how a single fertilised egg cell can give rise to a complex multi-organ organism like a human - and is also critical for faster and more effective development of medicines that target these biological molecules. However, certain types of biological molecules, such as proteins that exist inside biological membranes (termed 'membrane proteins'), present substantial challenges to modern methods of analysis. Here we propose to bring together multiple novel methods to study the structure and function of a membrane protein named 'Hedgehog acyltransferase' (HHAT), which is a key regulator of growth and development, and is also implicated in development of certain cancers in adults. The resulting molecular level understanding of HHAT will empower efforts to therapeutically target HHAT, and guide future studies of other similarly challenging membrane proteins.HHAT regulates the 'Hedgehog signalling pathway' that cells use to communicate with each other. The Hedgehog pathway is key to growth and development of animals, and was named after its discovery in fruit flies where disruption causes larvae to develop a spikey appearance like a hedgehog. Hedgehog signalling is generally turned off in healthy adults, but it is reactivated in certain cancers. Our research will approach the problem of understanding how HHAT functions and how this affects Hedgehog signalling using three distinct, but complimentary, approaches. We will use chemical biology to create variants of the molecules that HHAT modifies, which will allow us to understand how these molecules interact with HHAT. In parallel, we will use state-of-the-art structural biology methods to allow us to visualise the 3-dimensional architecture of HHAT at an atomic level. Finally, we will use these new insights to understand how HHAT works in cells, and to design new HHAT proteins that have altered preferences for the molecules they modify. These new designer HHAT's will be used to understand how HHAT regulates the distance and extent to which cells can communicate over.This research will provide fundamental understanding of the role of HHAT and Hedgehog signalling in development and in diseases such as cancer, and provide an important means to regulate cell-to-cell communication in designed 'synthetic' biological systems. It will also provide 3D structural information and identify regions where molecules can bind to HHAT, which will greatly accelerate drug discovery efforts. Further, this work will provide a roadmap to guide future studies against other related membrane proteins that are targets in a range of diseases.