Investigating the impact of lipid-protein interactions in membrane protein structure and conformational dynamics

研究脂质-蛋白质相互作用对膜蛋白结构和构象动力学的影响

• 批准号: 1817735
• 负责人: Linda Columbus
• 金额: $ 72.98万
• 依托单位: University of Virginia Main Campus
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2018
• 资助国家: 美国
• 起止时间: 2018-07-01 至 2023-06-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1817735&HistoricalAwards=false
• 关键词: Investigating; impact; lipid; protein; interactions

Membranes are the walls around cells and membrane proteins are the doors and the windows that allow passage of information and molecules across the wall. How do the walls (membrane) and windows (membrane protein) interact? Membranes are a complex mixture of lipids that interact directly with membrane proteins. The general principles of these interactions and how these interactions modulate membrane protein structure and function is largely unknown. In the last decade, there has been a surge of membrane protein structures that provide snapshots of what these proteins look like and provide a platform to hypothesize how these proteins carryout their functions. Often neglected in these hypotheses is the role of the lipid bilayer because of the lack of general principles describing lipid-protein interactions and straightforward experimental methods for determining these interactions. A systematic analysis of the impact of lipids on structure and conformational dynamics is needed and is provided in this project. The results of this research will impact many fields beyond molecular biophysics such as cell signaling and regulation, molecular assembly, and lipid metabolism and homeostasis. Through the research and educational goals of the project, the PI will impact the broader community by focusing on initiatives that (i) increase the participation of underrepresented groups in undergraduate STEM research and (ii) catalyze the use of effective and inclusive practices in undergraduate STEM education.To investigate general principles, two very different membrane proteins (both in structure and function) are investigated. The use of systematic variation of physical aspects of the membrane environment have been established to design experiments which address specific questions associated with lipid segregation and membrane mimic properties. Combined, the approaches, which utilize a variety of biophysical methods described in this project will determine if the lipid boundary is critical to membrane protein structure and function. The results of this research will provide a fundamental understanding and establish general principles for the role of lipid - protein interactions in (i) stabilizing membrane protein folds and (ii) facilitating conformational dynamics involved in catalysis. These results will impact the in vitro preparation of membrane proteins, the interpretation of membrane misfolding mutations, the assemblies of biomolecular complexes in the context of membranes, clustering in the membrane, and much more.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.

膜是细胞周围的壁，膜蛋白是允许信息和分子通过壁的门和窗户。壁（膜）和窗（膜蛋白）是如何相互作用的？膜是一种复杂的脂质混合物，直接与膜蛋白相互作用。这些相互作用的一般原理以及这些相互作用如何调节膜蛋白的结构和功能在很大程度上是未知的。在过去的十年里，有大量的膜蛋白结构提供了这些蛋白质看起来像什么的快照，并提供了一个平台来假设这些蛋白质是如何发挥其功能的。由于缺乏描述脂质-蛋白质相互作用的一般原理和确定这些相互作用的直接实验方法，在这些假设中经常被忽视的是脂质双分子层的作用。需要对脂类对结构和构象动力学的影响进行系统的分析，并在本项目中提供。这项研究的结果将影响分子生物物理学以外的许多领域，如细胞信号传导和调控、分子组装、脂质代谢和体内平衡。通过该项目的研究和教育目标，PI将通过关注以下举措来影响更广泛的社区：(i)增加代表性不足群体对本科STEM研究的参与；（ii）促进在本科STEM教育中使用有效和包容的实践。为了研究一般原理，研究了两种非常不同的膜蛋白（在结构和功能上）。利用膜环境物理方面的系统变化来设计实验，解决与脂质分离和膜模拟特性相关的具体问题。结合这些方法，利用本项目中描述的各种生物物理方法，将确定脂质边界是否对膜蛋白结构和功能至关重要。这项研究的结果将为脂质-蛋白质相互作用在(i)稳定膜蛋白折叠和（ii）促进催化过程中的构象动力学中的作用提供基本的理解和建立一般原理。这些结果将影响膜蛋白的体外制备，膜错误折叠突变的解释，膜环境下生物分子复合物的组装，膜中的聚类等等。该奖项反映了美国国家科学基金会的法定使命，并通过使用基金会的知识价值和更广泛的影响审查标准进行评估，被认为值得支持。

项目成果

Conformational dynamics of the membrane enzyme LspA upon antibiotic and substrate binding

• DOI: 10.1016/j.bpj.2022.04.038
• 发表时间: 2022-06-07
• 期刊: BIOPHYSICAL JOURNAL
• 影响因子: 3.4
• 作者: Caldwell, Tracy A.;Vickery, Owen N.;Columbus, Linda
• 通讯作者: Columbus, Linda

Solution NMR investigations of integral membrane proteins: Challenges and innovations

• DOI: 10.1016/j.sbi.2023.102654
• 发表时间: 2023-08-03
• 期刊: CURRENT OPINION IN STRUCTURAL BIOLOGY
• 影响因子: 6.8
• 作者: Necelis，Matthew;Mcdermott，Connor;Columbus，Linda
• 通讯作者: Columbus，Linda

The Fluidity of Phosphocholine and Maltoside Micelles and the Effect of CHAPS

磷酸胆碱和麦芽糖苷胶束的流动性及 CHAPS 的影响

• DOI: 10.1016/j.bpj.2019.03.019
• 发表时间: 2019
• 期刊: Biophysical Journal
• 影响因子: 3.4
• 作者: Kieber, Marissa;Ono, Tomihiro;Oliver, Ryan C.;Nyenhuis, Sarah B.;Tieleman, D. Peter;Columbus, Linda
• 通讯作者: Columbus, Linda