Sonomagnetic Imaging and Sonomechanical Control of Biological Processes in Deep Tissues

项目总结/摘要 观察和操纵细胞功能的新方法彻底改变了我们对生物学的理解。 这种方法在历史上经历了多次范式转变，从胡克的显微镜和卡哈尔的 从神经元染色到基于绿色荧光蛋白（GFP）和基于视蛋白的现代荧光成像 光遗传学这些现代遗传编码方法，通过使用基于蛋白质的试剂来定义， 可以由细胞表达，提供关键能力，如细胞特异性靶向表达，续 在分裂细胞中生产，并与最先进的基因工程方法结合。然而，由于大多数 这些蛋白质工具依赖于光学相互作用，它们从根本上受到~ 1 mm穿透的限制。 光进入不透明组织的深度。随着研究对象从细胞培养和半透明的大小增加 生物体如C.从小型啮齿动物到人类，这种限制变得越来越多。 严重。为了克服这一技术挑战，我的目标是开发下一代方法， 基因编码并能与深层渗透的能量形式交流。特别是，我将 利用气体囊泡（GVs）的独特物理和生化特性，这是一类充满气体的蛋白质， 只在某些光合微生物中发现了纳米结构。在目标1中，提出了一种新的方法，“声磁 成像”（SMI），将开发，它利用GV的双重能力，以诱导磁对比度 共振成像（MRI）并与超声脉冲相互作用以选择性地擦除这种对比度。同时， 在目标2中将开发一种控制基因表达的新方法，声机械控制（SMC），其中 超声脉冲可以使GV塌陷，并触发信号通路，以高空间分辨率激活基因表达。 精确且低能量沉积。在目标3中，我将把这些新方法整合到工程任务中 时空可追踪和可控的哺乳动物肠道微生物。这些目标的实现将 建立一个平台，设计益生菌，可以监测其功能和外部控制， 临床医生在精确的位置和时间提供治疗。这些技术的发明， 将激发人们对其他需要灵敏成像和细胞控制的生物医学研究的广泛兴趣 在深层组织中发挥作用。该提案还描述了研究专业知识培训，会议出席情况 以及领导技能的获得，这将使我成为一个有竞争力的候选人， 一个独立的研究计划，在一个主要的研究机构，并刺激对我的长期进展 目标是发展成像和控制技术，以研究完整的生物系统。

Project Summary / Abstract New ways to observe and manipulate cellular function have revolutionized our understanding of biology. Such methods have undergone multiple paradigm shifts in history, from Hooke's microscope and Cajal's staining of neurons, to modern fluorescent imaging based on green fluorescent protein (GFP) and opsin-based optogenetics. These modern genetically encoded methods, defined by their use of protein-based agents that can be expressed by cells, provide key capabilities such as cell-specific targeted expression, continued production in dividing cells, and coupling with state-of-the-art genetic engineering methods. However, as most of these protein tools rely on optical interactions, they are fundamentally limited by the ~ 1 mm penetration depth of light into opaque tissue. As the objects of study increase in size from cell cultures and translucent organisms such as C. elegans, via small rodents, to human beings, this limitation becomes increasingly severe. To overcome this technological challenge, I aim to develop next-generation methods that are both genetically encoded and able to communicate with deeply penetrant forms of energy. In particular, I will leverage the unique physical and biochemical properties of gas vesicles (GVs), a class of gas-filled protein- only nanostructures discovered in certain photosynthetic microbes. In Aim 1, a new method, “sonomagnetic imaging” (SMI), will be developed, which takes advantage of GVs' dual ability to induce contrast for magnetic resonance imaging (MRI) and interact with ultrasound pulses for selective erasing of such contrast. In parallel, a new method to control gene expression, sonomechanical control (SMC), will be developed in Aim 2 wherein ultrasound pulses can collapse GVs and trigger signaling pathways to activate gene expression at high spatial precision and low energy deposition. In Aim 3, I will integrate these novel methods to the task of engineering spatiotemporally trackable and controllable mammalian gut microbes. The completion of these aims will establish a platform for designing probiotics that can be monitored for their function and controlled externally by clinicians to deliver therapies at precise locations and times. Furthermore, the invention of these technologies will stimulate broad interest in other biomedical research that requires sensitive imaging and control of cellular function in deep-lying tissues. The proposal also describes research expertise training, conference attendance and the acquisition of leadership skills that, altogether, will prepare me as a competitive candidate to establish an independent research program at a major research institute and stimulate advances towards my long-term goal of developing imaging and control technologies to study intact biological systems.