Study plasma membrane nanodomains with quantitative super-resolution approaches

质膜是细胞内部和细胞外环境之间的物理屏障，允许独立的生命过程在没有细胞的情况下进行。膜受体负责调节细胞的命运和对外界刺激的反应。细胞膜上的信号传导是器官内细胞协调生长和分化的基础，在过去的40年里，科学家们获得了大量关于细胞膜组织的信息。最初被认为是含有随机分布的脂质和蛋白质的被动屏障，现在看来它们的组织更加复杂且受到严格的调控。在这些膜双分子层的平面内，精细平台的横向分离负责控制基本的细胞机制，包括受体信号传导、营养物质的摄取、免疫系统的调节等等。这些结构的表征由于缺乏能够测量其尺寸（在纳米范围内）和动态特性的方法而受到阻碍。我们的研究计划旨在解决这些基本问题。在我的实验室里，我们已经实施了新的尖端成像技术，称为超分辨率显微镜，能够以高时间分辨率（毫秒范围的十分之一）分辨纳米尺度的结构。在NSERC的支持下，我们的目标有三个方面：1）实现基于超分辨率显微镜的定量工具，以确定膜组件的纳米级组织; 2）通过氦束显微镜在细胞膜图像的背景下研究纳米结构域定位，以及3）创建细胞膜的邻近图。分辨率成像将成为生物学家和生物药理学家的主要工具，以更详细地了解我们的细胞在分子水平上如何发挥作用。我们将利用这些方法，进一步扩大他们的能力，并将其与创造性的生物化学方法相结合，以培养我们机构未来的科学家，并利用这些强大的工具来研究未回答的生物学问题。

The plasma membrane is a physical barrier between the cell interior and extracellular milieu, allowing independent vital processes to be carried out without the cells. Membrane receptors are responsible from regulating cell's fate and responses to external stimuli. Signal transduction across the plasma membrane is primordial to the coordinated growth, differentiation of cells within organs.In the last 40 years, scientists have obtained a great deal of information on the organization of the cell's membrane. Initially thought to be passive barrier containing randomly distributed lipids and proteins, it appears now that their organization is more complex and tightly regulated. Within the plane of these membrane bilayers, lateral segregations of fine platform are responsible for the control of fundamental cellular mechanisms, including receptor signaling, uptake of nutrients, regulation of the immune system and more.The characterization of these structures has been stymied by a lack of methodologies capable of measuring their size (in the nanometer range) and dynamic properties. It has then been also impossible to really clarify how membrane nanodomains are regulating cell signaling.Our research program is designed to address these fundamental questions. In my laboratory, we have already implemented new cutting-edge imaging techniques known as super-resolution microscopy, capable of resolving nanometer scale structures at high temporal resolution (10th of millisecond range). With the support of NSERC, our objectives are 3 folds: 1) to implement quantitative tools based on super-resolution microscopy to define the nanoscale organization of membrane components; 2) to investigate nanodomains localization in the context of the cell membrane image by helium beam microscopy and 3) to create a proximity map of the cell membrane.Super-resolution imaging will become a major tool for biologists and biophysicists to understand, with greater details, how our cells function at the molecular level. We will make use of these approaches, further expand their capabilities and combine them with creative biochemical approaches to train future scientists in our institution and make use of these powerful tool to investigate unanswered biological questions.