MEDIC - MicroED Imaging Center at UCLA

加州大学洛杉矶分校的医疗-微ED成像中心 项目摘要 我们建议在加州大学洛杉矶分校建立一个全国性的资源，用于发展、培训和传播 先进的电子衍射技术。低温电子显微镜(CryoEM)方法有望带来新的生命 高通量的大分子结构测定。低温电子显微镜克服了X射线的根本障碍 大分子络合物的衍射法测定：生长X射线级晶体。幸运的是， 微晶电子衍射(MicroED)的出现促进了蛋白质新结构的确定 在原子分辨率下从消失的小晶体。MicroED利用电子之间的强相互作用 和纳米级的三维晶体，并利用新兴的低温电磁仪器耦合 建立了结晶学方法。我们率先开发了MicroED，以实现里程碑式的发现，即我们 从小于波长的晶体中以原子分辨率确定以前未知的蛋白质结构 可见光。这些技术进步，加上先进的低温EM的更大可用性 仪器的出现为进一步改进高通量结构测定提供了机会。这个 发展新的、更有效的微电子能谱结构测定方法开辟了新的途径 用于全面探索仍达不到标准的复杂大分子结构 方法：研究方法。这些系统包括生长小的、脆弱的或不完美的晶体的大分子络合物。我们的 对MicroED的技术开发提出了四个方面的创新：(1)改进的样本 筛选和制备，(2)新的精制和阶段化方法，(2)论证了 对天然产物和小分子进行微电子衍射，以及(4)设计用于结构研究的新硬件 实时动态。与这些类型的组件相关的生物医学问题是广泛和有影响的 生物医学，既通过对疾病的基本了解，也通过启用新的治疗平台。 我们的关键人员团队汇集了来自各种形式的低温电子显微镜、结晶学、 生物化学、分子生物学和计算，以帮助开发下一代MicroED工具。这 工作将由全国各地的专家组领导的项目来提供信息，这些项目构成了 重大的结构性挑战。我们共同提出了一种资源，可以使纳米晶学和 面向非专家的MicroED常规方法。广泛的用户培训和社区参与将进一步 传播MicroED技术，并将新结构公之于众。

MEDIC – MicroED Imaging Center at UCLA Project Summary We are proposing to establish a national resource at UCLA for the development, training and dissemination of advanced electron diffraction technologies. Cryo-electron microscopy (cryoEM) methods promise new life to high-throughput macromolecular structure determination. CryoEM overcomes the fundamental barrier to X-ray diffraction determination of macromolecular complexes: growing X-ray grade crystals. Fortunately, the emergence of microcrystal electron diffraction (MicroED) facilitates the determination of new protein structures at atomic resolution from vanishingly small crystals. MicroED exploits the strong interaction between electrons and nano-scale three-dimensional crystals and takes advantage of emerging cryoEM instrumentation coupled to established crystallographic methods. We pioneered MicroED to achieve milestone discoveries, namely we determined previously unknown protein structures at atomic resolution from crystals smaller than the wavelength of visible light. These technological advances, coupled with the greater availability of advanced cryoEM instruments, present an opportunity for further improvement of high-throughput structure determination. The development of new and more efficient approaches to structure determination by MicroED opens new avenues for comprehensive exploration of complex macromolecular structures that remain out of reach for standard methods. These systems include macromolecular complexes that grow small, fragile, or imperfect crystals. Our proposed innovations to technology development in MicroED are in four categories: (1) improved sample screening and preparation, (2) novel refinement and phasing methods, (2) demonstrating the applicability of MicroED to natural products and small molecules, and (4) engineering new hardware for investigating structure dynamics in real time. The biomedical problems associated with these types of assemblies are broad and impact biomedicine, both through the basic understanding of disease and through enabling new therapeutic platforms. Our group of key personnel brings together expertise from all modalities of cryoEM, crystallography, biochemistry, molecular biology, and computation to help develop the next generation of MicroED tools. This effort will be informed by projects led by expert groups around the country working on projects that pose significant structural challenges. Together, we propose a resource that can make nanocrystallography and MicroED routine methodologies for non-experts. Extensive user training and community engagement will further disseminate the MicroED technology and bring new structures to light.