Lipid plasticity and its relevance for critical biological processes involving membrane reorganization

脂质可塑性及其与涉及膜重组的关键生物过程的相关性

• 批准号: 312634-2006
• 负责人: Lague, Patrick
• 金额: $ 1.46万
• 依托单位: Université Laval
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2007
• 资助国家: 加拿大
• 起止时间: 2007-01-01 至 2008-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=364606
• 关键词: Lipid; plasticity; its; relevance; critical

The cell membrane is of singular importance for life since it acts as a barrier to the cell environment and controls what goes in and what goes out. Moreover, membrane reorganization by fusion and fission is central to a number of biological processes, such as fertilization, viral infection, vesicle trafficking and cell division. Cell membranes are mainly composed of lipids, forming the framework of the membranes, and proteins, responsible for the biological activities, such as enzymatic processes. The phospholipids constitute the most important class of lipids found in Nature. These molecules are amphipatic, i.e. they have a hydrophilic part, commonly called the polar head, and a hydrophobic part composed of two aliphatic chains. When phospholipids are mixed with water in adequate concentrations, hydrophobic forces cause the aliphatic chains regroup together with the polar heads facing the water. Biological membranes are predominantly arranged as bilayers. Also, proteins with a hydrophobic nature bind to membranes. Recent work from our group shown that a peptide embedded in a bilayer has the ability to change the conformation or "shape" of the lipids. Based on this peptide-induced effect on the lipids, we then proposed the concept of "dynamically induced shape". This concept recognizes that the bilayer membrane is a conformationally plastic and dynamical environment that reacts in a complex way to the presence of impurities or a physical stress. The main objective of the proposed research program is to investigate membrane plasticity for two cases of high biological relevance, membrane fusion from viral infection and membrane fission by antimicrobial peptides. Complementary tools from structural bioinformatics will be used to achieve the goals of this innovative research program.

细胞膜对生命具有奇异的重要性，因为它是细胞环境的障碍，并控制了进水和外出。此外，通过融合和裂变进行的膜重组是许多生物学过程的核心，例如受精，病毒感染，囊泡运输和细胞分裂。细胞膜主要由脂质组成，形成膜的框架，以及负责生物学活性的蛋白质，例如酶促过程。磷脂构成自然界中发现的最重要的脂质类。这些分子是两亲的，即它们具有亲水性部分，通常称为极性头部，而疏水部分由两个脂肪族链组成。当磷脂与水中以足够浓度的水混合时，疏水力会导致脂肪族链与面向水的极头链再生。生物膜主要以双层形式排列。同样，具有疏水性质的蛋白质与膜结合。我们小组的最新工作表明，嵌入双层中的肽具有改变脂质构象或“形状”的能力。基于这种肽诱导的对脂质的影响，我们然后提出了“动态诱导形状”的概念。这个概念认识到双层膜是一种构象的塑性和动态环境，以复杂的方式对杂质或身体压力的存在做出反应。拟议的研究计划的主要目的是研究两种具有高生物学相关性的病例，病毒感染的膜融合和抗菌肽膜裂变的膜可塑性。结构生物信息学的互补工具将用于实现该创新研究计划的目标。