CAREER: Discrepancies in raft size between cellular and model membranes: Solid-state NMR measurements of protein effect on lipid raft size

在这个由化学系实验物理化学项目资助的职业奖项中，梅根·斯宾塞教授建议研究膜蛋白在调节细胞膜中脂筏大小方面的作用。脂筏被认为在膜上蛋白质的组织中发挥重要作用，通过隔离特定的膜蛋白而避开其他蛋白来积极协调蛋白质-蛋白质的相互作用。为了测量木筏的大小，她将开发一种基于扩散的技术，将固态核磁共振光谱与磁共振成像(MRI)相结合，能够测量小至200纳米的木筏。脂筏中脂类的表观扩散受脂筏边界的约束，通过测定脂筏的最大均方根位移来测量筏子的大小。这项拟议的工作将发展固体核磁共振光谱作为研究膜筏的生物物理工具，并加深我们对脂筏在调节蛋白质功能中的作用以及蛋白质在调节脂筏形成中的作用的理解。关于脂筏-蛋白质相互作用的详细信息将有助于医学研究人员更好地了解与脂筏相关的疾病，如病毒感染和Pron疾病。斯宾塞教授将为二年级本科生开发一门一学分的实验室实用技术课程，重点是实验室文化、良好的笔记本保存和实验计划。为了练习这些技能，学生们将设计在地球磁场核磁共振中进行的实验。早期接触研究会增加理科专业学生的留存率，特别是那些代表性不足的人群，这门课程让二年级学生为来年夏天的研究工作做好准备。

In this CAREER award, funded by the Experimental Physical Chemistry Program of the Division of Chemistry, Professor Megan Spence proposes to study the role of membrane proteins in modulating the size of lipid rafts in the cell membrane. Lipid rafts are hypothesized to play an important role in the organization of proteins in the membrane, actively orchestrating protein-protein interactions by sequestering particular membrane proteins while shunning others. To measure the size of the rafts, she will develop a diffusion-based technique combining solid-state NMR spectroscopy with magnetic resonance imaging (MRI), capable of measuring rafts as small as 200 nm. The apparent diffusion of lipids in a raft is constrained by the lipid raft boundaries, and the size of the rafts will be measured by determining the maximum root-mean-square displacement of the lipids. The proposed work will develop solid-state NMR spectroscopy as a biophysical tool for the study of membrane rafts, and further our understanding of the role of lipid rafts in modulating protein function and the role of proteins in modulating lipid raft formation. Detailed information about lipid raft-protein interactions will help medical researchers better understand raft-related diseases like viral infection and prion diseases. Professor Spence will develop a one-credit practical laboratory techniques class for second year undergraduate students, focusing on laboratory culture, good notebook keeping, and planning of experiments. To practice these skills, students will design experiments to be carried out in an Earth's-field MRI. Early exposure to research increases the retention of science majors, particularly those of underrepresented populations, and this course poises sophomores for research work in the following summer.