Unravelling the biological function of heparan sulphate domain structure by three-dimensional analysis

通过三维分析揭示硫酸乙酰肝素结构域的生物学功能

• 批准号: BB/G006768/1
• 负责人: Andrew Almond
• 金额: $ 50.4万
• 依托单位: University of Manchester
• 依托单位国家: 英国
• 项目类别: Research Grant
• 财政年份: 2009
• 资助国家: 英国
• 起止时间: 2009 至 无数据
• 项目状态: 已结题
• 来源: https://gtr.ukri.org/projects?ref=BB%2FG006768%2F1
• 关键词: Unravelling; biological; function; heparan; sulphate

This study aims to unravel some of the mysteries surrounding the large polymeric molecules called glycosaminoglycans, which have played a crucial part in the evolution of multicellular animals from single-celled organisms. In the mammal, glycosaminoglycans fill the space between cells, bonding them together, conferring strength to organs, joints and skin, while allowing cells to grow and change. Considering their omnipresence in the body it is not surprising that they have many different functions in mammals. However, within the glycosaminoglycan family, distinct members can be identified with slight differences in their chemical structure and question that remains is how these chemical differences lead to the observed diverse biology. For example, hyaluronan lubricates joints and fills the eyeballs, chondroitin sulphate is an essential constituent of joint linings and brain, dermatan sulphate gives elasticity to heart valves and heparan sulphate (sometimes called heparin) is found on the walls of arteries and commonly used as an anticoagulant during surgery. The overall aim of our research, including the project described here, is to investigate the, as yet, poorly understood relationship between structure and function in glycosaminoglycans, by providing detailed microscopic molecular three-dimensional information using techniques that we have perfected over the last 10 years. Of the glycosaminoglycans, heparan sulphate has been found to have the most complicated and diverse set of chemical decorations. In fact, it has been found to possess a molecular barcode, which is imprinted along its length and is encoded by the sulphate chemistry and other modifications. This barcode is read by cells, it is hypothesised, which use it as a signal to change their behaviour, suggesting that exciting new biological insights and medical therapies are possible if we can understand the nature of this molecular barcode and its reader. Our investigations have led to a hypothesis that the heparan sulphate barcode is encoded in the local chain flexibility, in which variable rigid sections are separated by flexible hinges. We aim to test this hypothesis by using a molecular microscope (nuclear magnetic resonance), which can, in principle, determine the shape of the heparan sulphate chain along its length and also its flexibility. However, while there are currently good molecular microscopy techniques for proteins (such as x-ray crystallography), the flexibility of heparan sulphate means that established techniques cannot be used, a key reason that heparan sulphate local flexibility has not been investigated in detail. Fortunately, we have recently pioneered a novel set of techniques that can unravel the three-dimensional shape and flexibility of glycosaminoglycans. By applying these technological advances to heparan sulphate, we aim to uncover its molecular shape and flexibility. This will help unravel the exact nature of the molecular barcode and hence explain how it interacts with cells and other molecules in the body. The knowledge gained will help us to uncover new biology, such as understanding how cells assemble themselves, treat diseases that result from incorrect functioning of glycosaminoglycans, and allow progress in tissue engineering and regenerative medicine. Such information can also drive the development of novel chemical mimetics that are urgently needed in the clinic (annual revenues from sales of heparin total many billions of dollars).

这项研究旨在揭开糖胺聚糖这一大聚合分子的一些谜团，这种大分子在从单细胞生物进化为多细胞动物的过程中发挥了至关重要的作用。在哺乳动物中，糖胺聚糖填充细胞之间的空间，将它们粘合在一起，赋予器官、关节和皮肤力量，同时允许细胞生长和变化。考虑到它们在体内无处不在，它们在哺乳动物中具有许多不同的功能也就不足为奇了。然而，在糖胺聚糖家族中，可以通过化学结构的细微差异来识别不同的成员，剩下的问题是这些化学差异如何导致观察到的多样化生物学。例如，透明质酸润滑关节并填充眼球，硫酸软骨素是关节内膜和大脑的重要成分，硫酸皮肤素赋予心脏瓣膜弹性，硫酸乙酰肝素（有时称为肝素）存在于动脉壁上，通常在手术期间用作抗凝剂。我们研究的总体目标，包括这里描述的项目，是通过使用我们在过去 10 年中完善的技术提供详细的微观分子三维信息，来研究迄今为止人们知之甚少的糖胺聚糖结构和功能之间的关系。在糖胺聚糖中，硫酸乙酰肝素被发现具有最复杂和多样化的化学修饰。事实上，人们发现它具有分子条形码，该条形码沿其长度印记，并由硫酸盐化学和其他修饰编码。假设细胞可以读取该条形码，细胞将其用作改变其行为的信号，这表明如果我们能够了解该分子条形码及其读取器的性质，则令人兴奋的新生物学见解和医学疗法是可能的。我们的研究得出了一个假设，即硫酸乙酰肝素条形码是在局部链柔性中编码的，其中可变的刚性部分由柔性铰链分开。我们的目标是通过使用分子显微镜（核磁共振）来测试这一假设，原则上，分子显微镜可以确定硫酸乙酰肝素链沿其长度的形状及其柔韧性。然而，虽然目前有很好的蛋白质分子显微镜技术（例如X射线晶体学），但硫酸乙酰肝素的灵活性意味着现有技术无法使用，这是硫酸乙酰肝素局部灵活性尚未得到详细研究的一个关键原因。幸运的是，我们最近开创了一套新颖的技术，可以解开糖胺聚糖的三维形状和灵活性。通过将这些技术进步应用于硫酸乙酰肝素，我们的目标是揭示其分子形状和灵活性。这将有助于揭示分子条形码的确切性质，从而解释它如何与体内的细胞和其他分子相互作用。获得的知识将帮助我们发现新的生物学，例如了解细胞如何自我组装，治疗因糖胺聚糖功能不正确而导致的疾病，并促进组织工程和再生医学的进步。这些信息还可以推动临床急需的新型化学模拟物的开发（肝素的年销售收入总计数十亿美元）。

项目成果

Dependence of pyranose ring puckering on anomeric configuration: methyl idopyranosides.

• DOI: 10.1021/jp303183y
• 发表时间: 2012-06-07
• 期刊: JOURNAL OF PHYSICAL CHEMISTRY B
• 影响因子: 3.3
• 作者: Sattelle, Benedict M.;Bose-Basu, Bidisha;Tessier, Matthew;Woods, Robert J.;Serianni, Anthony S.;Almond, Andrew
• 通讯作者: Almond, Andrew

Proteoglycans and their heterogeneous glycosaminoglycans at the atomic scale.

蛋白聚糖及其在原子量表处的异质糖胺聚糖。

• DOI: 10.1021/bm5018386
• 发表时间: 2015-03-09
• 期刊: BIOMACROMOLECULES
• 影响因子: 6.2
• 作者: Sattelle, Benedict M.;Shakeri, Javad;Cliff, Matthew J.;Almond, Andrew
• 通讯作者: Almond, Andrew