Desiphering the structural origins of functional multimodality in bacterial mechanosensitive ion channels

解析细菌机械敏感离子通道功能多模态的结构起源

• 批准号: BB/S018069/2
• 负责人: Christos Pliotas
• 金额: $ 7.04万
• 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: 2023
• 资助国家: 英国
• 起止时间: 2023 至 无数据
• 项目状态: 未结题
• 来源: https://gtr.ukri.org/projects?ref=BB%2FS018069%2F2
• 关键词: Desiphering; structural; origins; functional; multimodality

Ion channels are central to life sciences due to direct involvement in signal transduction, aging, cancer and neurodegeneration. Despite progress in the fundamental understanding of the structure and function of specific membrane proteins (Nobel Prizes in Chemistry 1988, 1997, 2003 and 2012), this has only been the tip of the iceberg. There is now an immediate need for the development of novel triggers to control pores in the cell membrane of deadly pathogens and tackle antimicrobial resistance, the most common cause of death worldwide. We anticipate to achieve that by exploiting an ancient and ubiquitous mechanism of ion channel regulation named mechanosensation. The latter is the ability of membrane proteins to sense tension changes occurring within the lipid membrane and respond to these by altering their structure and function. This proposal aims to gain a fundamental understanding of mechanosensation and decipher the molecular basis of its co-existence with other forms of ion channel regulation. To this end, we will dissect the individual steps that form its molecular basis and identify the common, but essential structural elements responsible to transduce pressure-sensing abilities to channels. The fundamental aspect of the underlying impact of the lipid membrane in ion channel regulation along with the physiological role of the functional versatility of pressure sensitive channels will be elucidated. To this end, we will identify the unique structural features which allow functional multimodality of mechanosensitive channels and their ability to respond to other stimuli, such as ions, pH or specific molecules, in addition to mechanical triggers. Within the project we will develop and follow an integrated multidisciplinary approach in order to establish a link between mechanical-activation and ligand-gating. The proposed studies will involve using a suite of state-of-the-art structural (Cryo Electron Microscopy and X -Ray crystallography), biochemical (Protein Purification), biophysical (Electron Paramagnetic Resonance spectroscopy and Electrophysiology) and sophisticated computational methods (Molecular Dynamics) to address questions pertaining to the mechanism and regulation of distinct members of the bacterial mechanosensitive ion channel family at a molecular level.Collectively, we anticipate to translate forces within the membrane participating in the mechanical activation of channels into specific molecular stimuli, which would mimic mechanotransduction. Similar to optogenetics, a field which has massively evolved over the last years and is based on the interaction of proteins with the ancient physical property of light, pressure sensing, one of nature's most fundamental regulatory mechanisms, would enable a radically novel field to emerge.

离子通道由于直接参与信号转导、衰老、癌症和神经退行性变而在生命科学中处于中心地位。尽管在对特定膜蛋白的结构和功能的基本理解方面取得了进展（诺贝尔化学奖1988年，1997年，2003年和2012年），但这只是冰山一角。现在迫切需要开发新的触发器来控制致命病原体细胞膜中的孔，并解决全球最常见的死亡原因-抗菌素耐药性。我们期望通过利用一种古老而普遍存在的离子通道调节机制来实现这一目标，该机制称为机械感觉。后者是膜蛋白感知脂质膜内发生的张力变化并通过改变其结构和功能对其作出反应的能力。该提案旨在获得对机械感觉的基本理解，并破译其与其他形式的离子通道调节共存的分子基础。为此，我们将剖析构成其分子基础的各个步骤，并确定负责将压力传感能力转换到通道的常见但重要的结构元件。脂质膜在离子通道调节中的潜在影响的基本方面沿着压力敏感通道的功能多样性的生理作用将被阐明。为此，我们将确定独特的结构特征，使功能的多模态的机械敏感通道和他们的能力，以响应其他刺激，如离子，pH值或特定的分子，除了机械触发器。在该项目中，我们将开发和遵循一个综合的多学科方法，以建立机械激活和配体门控之间的联系。拟议的研究将涉及使用一套最先进的结构（低温电子显微镜和X射线晶体学），生物化学（蛋白质纯化），生物物理（电子顺磁共振光谱学和电生理学）和复杂的计算方法（分子动力学）为了解决与细菌机械敏感离子通道家族的不同成员在分子水平上的机制和调节有关的问题，总的来说，我们期望将参与通道机械激活的膜内的力转化为特定的分子刺激，这将模拟机械转导。与光遗传学类似，光遗传学是一个在过去几年中大规模发展的领域，它基于蛋白质与光的古老物理性质的相互作用，压力传感是自然界最基本的调节机制之一，将使一个全新的领域出现。

项目成果

Membrane force reception: mechanosensation in G protein-coupled receptors and tools to address it

• DOI: 10.1016/j.cophys.2023.100689
• 发表时间: 2023-07-06
• 期刊: CURRENT OPINION IN PHYSIOLOGY
• 影响因子: 2.5
• 作者: Hardman，Katie;Goldman，Adrian;Pliotas，Christos
• 通讯作者: Pliotas，Christos

Darobactin B Stabilises a Lateral-Closed Conformation of the BAM Complex in E. coli Cells

Darobactin B 稳定大肠杆菌细胞中 BAM 复合物的横向闭合构象

• DOI: 10.1002/ange.202218783
• 发表时间: 2023
• 期刊: Angewandte Chemie
• 作者: Haysom S