Chemical Tools for Probing Histone Deacetylase Multiprotein Complexes in Disease

开发新的化学工具和探针对于了解细胞中多方面蛋白质和酶的功能及其在疾病中的作用至关重要。许多酶催化对DNA和DNA相关蛋白质的化学修饰，调节哪些基因‘开启’和‘关闭’，通常被称为表观基因组。组蛋白脱乙酰酶(HDAC)是一类从DNA相关的组蛋白中去除乙酰基的酶。细胞中存在许多具有结构相似性的HDAC同工酶，这使得选择性地探测这些酶成为一个挑战。此外，相同的HDAC同工酶可以作为催化亚单位被结合到许多更大的多蛋白辅阻遏子复合体中，从而该复合体对于HDAC的不同生物学功能是必不可少的。HDAC活性异常与癌症和阿尔茨海默氏症等疾病有关，但目前的药物缺乏HDAC酶的选择性，并与衰弱的副作用有关。拟议的研究将提供新的化学工具，旨在调节具有多蛋白复合体选择性的HDAC酶。设计化合物选择性地针对特定的HDAC络合物是探索这类具有显著治疗潜力的络合物功能的一种新方法。这将通过三个目标来实现。目的一是制备双官能化弹头多肽，设计用于同时结合特定复合体中的两个酶位点。目标二集中于化合物的开发，以促进多蛋白复合体结构完整性和功能所需的亚单位酶的选择性降解。目的三扩展了目标二的方法，目的二是研究其他化合物的合成和验证，以降解具有复杂选择性的其他组蛋白脱乙酰酶。所开发的化学工具将在研究HDAC多蛋白复合体在疾病中的作用方面具有重要应用，这些工具还将用于未来治疗癌症等疾病的药物化合物的开发。

The development of new chemical tools and probes is vital to understanding the functions of multifaceted proteins and enzymes in the cell and their role in disease. Many enzymes catalyse chemical modifications to DNA and DNA associated proteins regulating which genes are 'switched on' and 'off', often termed the epigenome. Histone deacetylases (HDAC) are a class of enzyme that remove acetyl groups from DNA associated histone proteins. The presence of many HDAC isoenzymes in the cell, with structural similarity, makes probing these enzymes selectively a challenge. Further to this, the same HDAC isoenzyme can be incorporated as a catalytic sub-unit into a number of much larger multiprotein corepressor complexes, whereby the complex is essential to the distinct biological function of the HDAC. Abnormal HDAC activity is associated with diseases including cancer and Alzheimer's yet current drugs lack HDAC enzyme selectivity and are associated with debilitating side effects.The proposed research will deliver novel chemical tools designed to modulate HDAC enzymes with multiprotein complex selectivity. Designing compounds to selectively target a specific HDAC complex is a novel approach towards probing the function of such complexes with significant therapeutic potential. This will be achieved by three objectives. Objective one involves the preparation of dual functionalised warhead peptides designed to bind two enzymatic sites simultaneously in a specific complex. Objective two focuses on the development of compounds to facilitate selective degradation of a sub-unit enzyme required for multiprotein complex structural integrity and function. Objective three broadens on the approaches from objective two investigating the synthesis and validation of other compounds to degrade other histone deacetylase enzymes with complex selectivity. The chemical tools developed will have important applications in studying the roles of HDAC multiprotein complexes in disease, and the tools will also be used for future medicinal compound development to treat diseases such as cancer.