Mechanisms of Morphogen Transport and Interpretation in Early Embryos

早期胚胎中形态发生素运输和解释的机制

• 批准号: 10257934
• 负责人: Nathan Dale Lord
• 金额: $ 24.9万
• 依托单位: UNIVERSITY OF PITTSBURGH AT PITTSBURGH
• 依托单位国家: 美国
• 财政年份: 2020
• 资助国家: 美国
• 起止时间: 2020-11-01 至 2023-10-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/10257934
• 关键词: Adopted; Advisory Committees; Award; Biochemical; Biology; Biophysics; Cell Differentiation process; Cells; Congenital Abnormality; Core Facility; Developmental Biology; Diffuse; Diffusion; Dose; Embryo; Embryology; Embryonic Development; Endoderm; Exposure to; Feedback; Freedom; Gene Expression; Gene Expression Profile; Genes; Genetic; Genetic Enhancer Element; Genetic Transcription; Germ Layers; Goals; Grant; Human; In Vitro; Individual; Instruction; International; Joints; Ligands; Malignant Neoplasms; Measures; Medicine; Mentors; Mentorship; Mesoderm; Modeling; Molecular and Cellular Biology; Nodal; Noise; Optics; Organoids; Outcome; Pathway interactions; Pattern; Play; Positioning Attribute; Probability; Production; Randomized; Research; Role; Running; SET gene; Schedule; Series; Signal Transduction; Signaling Molecule; Source; Specific qualifier value; Strabismus; Students; Testing; Textbooks; Time; Tissue Engineering; Tissues; Training; Work; Writing; Zebrafish; base; blastocyst; blastomere structure; career; cell fate specification; cell motility; cofactor; experience; experimental study; gastrulation; graduate student; improved; in vivo; inhibitor/antagonist; meetings; member; morphogens; mutant; nodal protein; optogenetics; predictive modeling; programs; quantitative imaging; regenerative; response; skills; source localization; transcriptomics; vertebrate embryos

PROJECT ABSTRACT The long-term goal of this project is to understand how embryos accurately transmit instructions to their constituent cells. This proposal focuses on signaling by Nodal, a model morphogen that induces endoderm and mesoderm formation in early vertebrate embryos. Genetic and biochemical studies demonstrate that target cells select fates based on their position a gradient of Nodal signaling activity. However, the mechanisms of gradient formation and signal interpretation remain unclear. The proposed experiments will test competing mechanisms for the spatial spread of signaling from an endogenous Nodal source (Aim 1), and explain how similar signaling levels can specify more than one cell fate (Aim 2). These studies will be carried out in zebrafish to take advantage of its unique genetic and optical tractability. This work will resolve controversies concerning the role of diffusion in transporting endogenous Nodal ligands (K99), explore whether stochastic noise in Nodal signaling influences germ layer specification in a vertebrate embryo (K99, R00) and identify new Nodal-dependent gene expression programs (R00). Clarifying how Nodal signaling functions in vivo may also have implications for medicine, as misregulation of Nodal signaling can drive birth defects and cancer in humans. Finally, understanding the mechanisms that allow Nodal signals to transmit precise instructions will inform tissue engineering and regenerative biology, as Nodal is used to control cell differentiation in vitro. My career goal is to run an academic lab that studies how developing embryos achieve precise patterning in the face of unexpected perturbations. The proposed experiments will give me the experience in embryology, zebrafish genetics and optogenetics required for this goal. I have developed a detailed training plan with my mentor, Dr. Alexander Schier, to help me transition to independence. I will meet regularly with Dr. Schier to discuss research progress, strategies for grant writing, student mentorship and lab management. To practice my mentorship skills, I will oversee the work of a graduate student. To broaden my scientific network, I will present my work at two international meetings per year and participate in joint lab meetings with the Megason, Zon and Ramanathan groups at Harvard. To seek out additional mentorship, I assembled a K99 advisory committee consisting of Dr. Adam Cohen, Dr. Allon Klein, and Dr. Sean Megason. Their expertise in optogenetics, single-cell transcriptomics and quantitative imaging will help me to execute my research plan on the proposed schedule. As a member of the Harvard Department of Molecular and Cellular Biology, I will have access to leaders in developmental biology, biophysics and genetics, as well as cutting-edge core facilities. The Pathway to Independence Award will provide the time and freedom required to initiate an ambitious research program on the mechanisms of robust patterning in developing embryos.

项目摘要 该项目的长期目标是了解胚胎如何准确地传输指令 组成细胞。该提案的重点是Nodal的信号传导，Nodal是一种模型形态，可诱导内胚层和 早期脊椎动物胚胎中的中胚层形成。遗传和生化研究表明靶标 细胞根据其位置选择命运是节点信号活性的梯度。但是，机制 梯度形成和信号解释尚不清楚。拟议的实验将测试竞争 从内源性淋巴结源（AIM 1）的信号传导空间传播的机制（AIM 1），并解释如何 相似的信号水平可以指定多个细胞命运（AIM 2）。这些研究将在 斑马鱼利用其独特的遗传和光学障碍。这项工作将解决争议 关于扩散在运输内源性淋巴结配体（K99）中的作用（K99），探索是否随机 淋巴结信号中的噪声会影响脊椎动物胚胎（K99，R00）中的细菌层规范并识别新的 结节依赖性基因表达程序（R00）。阐明淋巴结信号在体内的功能也可能 对医学有影响，因为淋巴结信号传导的正调会导致先天缺陷和癌症 人类。最后，了解允许节点信号传输精确指示的机制将 告知组织工程和再生生物学，因为节点用于在体外控制细胞分化。 我的职业目标是运行一个学术实验室，研究开发胚胎如何实现精确图案 意外扰动的面孔。拟议的实验将为我提供胚胎学的经验， 该目标需要斑马鱼遗传学和光遗传学。我已经制定了一个详细的培训计划 导师亚历山大·席尔（Alexander Schier）博士帮助我过渡到独立。我将定期与Schier博士见面 讨论研究进度，授予写作策略，学生指导和实验室管理。练习 我的指导能力，我将监督研究生的工作。为了扩大我的科学网络，我将 每年在两次国际会议上介绍我的工作，并参加与Megason的联合实验室会议 哈佛大学的Zon和Ramanathan组。为了寻求其他指导，我集会了K99咨询 由亚当·科恩（Adam Cohen）博士，阿隆·克莱因（Allon Klein）博士和肖恩·梅加森（Sean Megason）博士组成的委员会。他们的专业知识 光遗传学，单细胞转录组学和定量成像将帮助我执行我的研究计划 拟议的时间表。作为哈佛分子和细胞生物学系的成员，我将拥有 进入发育生物学，生物物理学和遗传学以及尖端核心设施的领导者。 获得独立奖的途径将为发起雄心勃勃的时间和自由 研究计划在开发胚胎中鲁棒图案的机制。