A structural context for the mechanism of Uncoupling protein-1

解偶联蛋白-1 机制的结构背景

• 批准号: BB/S00940X/1
• 负责人: Paul Crichton
• 金额: $ 55.23万
• 依托单位: University of East Anglia
• 依托单位国家: 英国
• 项目类别: Research Grant
• 财政年份: 2019
• 资助国家: 英国
• 起止时间: 2019 至 无数据
• 项目状态: 已结题
• 来源: https://gtr.ukri.org/projects?ref=BB%2FS00940X%2F1
• 关键词: structural; context; mechanism; Uncoupling; protein

Most of the energy that we gain from the breakdown of sugars, fats and other food components is harnessed by mitochondria, the 'power plants' of our cells. However, the process of energy conversion is not 100% efficient. In specialised 'brown fat' cells of mammals, the process is pro-actively 'short circuited' to burn off calories as heat. These cells do this using a particular protein called uncoupling protein 1 (UCP1). Heat production using UCP1 is important for many mammals including livestock to survive cold temperatures, especially newborns. Though it is also beneficial for adult humans. Active brown fat tends to occur in leaner people who are less likely to develop age-related obesity, consistent with the tissue expending excess calories and improving health. UCP1 activity in brown fat helps remove glucose and fat from the blood, which can help combat diabetes. At present, obesity and related poor health conditions are growing as a major national and international problem for which a better understanding of metabolism is urgently needed.There is now significant scientific research worldwide into ways to encourage the development of brown fat as a viable means to increase calorie-expenditure to deliver better health. However, an important feature of brown fat is that UCP1 is not inherently active in the cells and must be specifically 'switched on' to burn calories for heat. This normally occurs through the action of regulator molecules that activate UCP1 in response to physiological stimuli such as cold temperatures. Therapeutic strategies to artificially activate UCP1 in the absence of physiological stimuli have the potential to greatly increase the capacity of the tissue to burn calories. Yet at present we do not know how UCP1 works nor how the regulator molecules interact with the protein to turn it on.UCP1 is a membrane protein, which are generally difficult to study due to their insoluble nature and instability when isolated. Recently, however, there have been some key advances in our understanding of how a membrane protein related to UCP1 works, which provides new opportunities to determine the molecular mechanism of UCP1. My investigations have provided new methods to purify and assess UCP1, which have revealed the basic functional unit of the protein and the associated lipid molecules that stabilise it. The work outlined here aims to capitalize on these advances and clarify the molecular nature of UCP1. The protein will be purified from natural sources (newborn lambs) as well as yeast that have been engineered to make it. Details on how regulator molecules interact with the isolated protein will be investigated using biophysical methods that monitor either the heat released from the binding event or the associated changes in the protein's stability that occurs. UCP1 will also be incorporated into artificial 'liposome' membranes, so that details on how regulators influence its activity can be assessed. Genetic methods will be used to alter key parts of the protein to help determine where activating molecules binds, as well as the function of the protein's other notable structural features. Additionally, experiments to crystallise UCP1 and use x-ray crystallography methods to gain a detailed picture of what the protein looks like will be carried out.These studies will provide valuable insight into the molecular process used by UCP1, which will advance our fundamental understanding of how membrane proteins work but also the way in which energy metabolism is controlled in cells. The details revealed may provide clues to identify other cellular components involved in UCP1's activation, and will also be invaluable to rationalise therapeutic strategies to activate energy expenditure pathways for targeting obesity and metabolic disease.

我们从糖、脂肪和其他食物成分的分解中获得的大部分能量都是由线粒体--我们细胞的“发电厂”--利用的。然而，能量转换的过程并不是100%有效的。在哺乳动物专门的“棕色脂肪”细胞中，这一过程是主动“短路”的，以燃烧热量的形式燃烧卡路里。这些细胞使用一种称为解偶联蛋白1（UCP 1）的特殊蛋白质来完成这一过程。利用UCP 1产生热量对于许多哺乳动物（包括牲畜）在寒冷的温度下生存非常重要，特别是新生儿。这对成年人也有好处。活跃的棕色脂肪倾向于出现在较瘦的人身上，他们不太可能患上与年龄相关的肥胖症，这与消耗多余热量和改善健康的组织一致。棕色脂肪中的UCP 1活性有助于从血液中清除葡萄糖和脂肪，这有助于对抗糖尿病。目前，肥胖症和相关的健康状况不佳正在成为一个主要的国家和国际问题，迫切需要更好地了解新陈代谢。目前，世界范围内有大量的科学研究，以鼓励棕色脂肪的发展，作为一种可行的手段，以增加热量消耗，以提供更好的健康。然而，棕色脂肪的一个重要特征是UCP 1在细胞中并不具有固有的活性，必须专门“打开”以燃烧热量。这通常通过调节分子的作用发生，调节分子响应生理刺激（如低温）激活UCP 1。在没有生理刺激的情况下人工激活UCP 1的治疗策略有可能大大增加组织燃烧卡路里的能力。然而，目前我们还不知道UCP 1是如何工作的，也不知道调节分子如何与蛋白质相互作用来打开它。UCP 1是一种膜蛋白，由于其不溶性和分离时的不稳定性，通常很难研究。然而，最近，在我们对UCP 1相关的膜蛋白如何工作的理解方面取得了一些关键进展，这为确定UCP 1的分子机制提供了新的机会。我的研究提供了新的方法来纯化和评估UCP 1，这揭示了蛋白质的基本功能单元和相关的脂质分子，稳定它。这里概述的工作旨在利用这些进展，并澄清UCP 1的分子性质。该蛋白质将从天然来源（新生羔羊）以及经过工程改造的酵母中纯化。关于调节分子如何与分离的蛋白质相互作用的细节将使用生物物理方法进行研究，这些方法监测结合事件释放的热量或发生的蛋白质稳定性的相关变化。UCP 1也将被整合到人工“脂质体”膜中，这样就可以评估调节剂如何影响其活性的细节。遗传方法将用于改变蛋白质的关键部分，以帮助确定激活分子结合的位置，以及蛋白质其他显著结构特征的功能。此外，将进行结晶UCP 1的实验，并使用X射线晶体学方法获得蛋白质外观的详细图像。这些研究将为UCP 1使用的分子过程提供有价值的见解，这将促进我们对膜蛋白如何工作的基本理解，以及细胞中能量代谢的控制方式。揭示的细节可能为识别参与UCP 1激活的其他细胞成分提供线索，并且对于合理化治疗策略以激活针对肥胖和代谢疾病的能量消耗途径也将是非常宝贵的。

项目成果

Activating ligands of Uncoupling protein 1 identified by rapid membrane protein thermostability shift analysis

通过快速膜蛋白热稳定性位移分析鉴定解偶联蛋白 1 的激活配体

• DOI: 10.1101/2022.02.03.478984
• 发表时间: 2022
• 作者: Cavalieri R

Activating ligands of Uncoupling protein 1 identified by rapid membrane protein thermostability shift analysis.

• DOI: 10.1016/j.molmet.2022.101526
• 发表时间: 2022-08
• 期刊: MOLECULAR METABOLISM
• 影响因子: 8.1
• 作者: Cavalieri, Riccardo;Hazebroek, Marlou Klein;Cotrim, Camila A.;Lee, Yang;Kunji, Edmund R. S.;Jastroch, Martin;Keipert, Susanne;Crichton, Paul G.
• 通讯作者: Crichton, Paul G.

Structural basis of purine nucleotide inhibition of human uncoupling protein 1.

• DOI: 10.1126/sciadv.adh4251
• 发表时间: 2023-06-02
• 期刊: SCIENCE ADVANCES
• 影响因子: 13.6
• 作者: Jones, Scott A.;Gogoi, Prerana;Ruprecht, Jonathan J.;King, Martin S.;Lee, Yang;Zogg, Thomas;Pardon, Els;Chand, Deepak;Steimle, Stefan;Copeman, Danielle M.;Cotrim, Camila A.;Steyaert, Jan;Crichton, Paul G.;Moiseenkova-Bell, Vera;Kunji, Edmund R. S.
• 通讯作者: Kunji, Edmund R. S.