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: 10517288
• 负责人: Nathan Dale Lord
• 金额: $ 23.65万
• 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/10517288
• 关键词: Adopted; Advisory Committees; Award; Biochemical; Biophysics; Cell Differentiation process; Cells; Communication; 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; blastocyst; blastomere structure; career; cell fate specification; cell motility; cofactor; embryo cell; experience; experimental study; gastrulation; graduate student; improved; in vivo; inhibitor; meetings; member; migration; morphogens; mutant; nodal protein; optogenetics; predictive modeling; programs; quantitative imaging; regenerative biology; response; skills; source localization; transcriptomics; transmission process; 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将指令传递给他们的大脑。 组成细胞该提议集中于Nodal的信号传导，Nodal是诱导内胚层和 早期脊椎动物胚胎中胚层的形成。遗传和生物化学研究表明， 细胞选择命运的基础上，他们的位置梯度的Nodal信号传导活动。然而， 梯度形成和信号解释仍不清楚。拟议的实验将测试竞争 内源性Nodal信号源的空间传播机制（Aim 1），并解释如何 相似的信号传导水平可以指定一种以上的细胞命运（Aim2）。这些研究将在 斑马鱼利用其独特的遗传和光学可追踪性。这项工作将解决争议 关于扩散在转运内源性Nodal配体（K99）中的作用，探讨是否随机 Nodal信号中的噪声影响脊椎动物胚胎（K99，R00）的胚层特化，并识别新的 节点依赖性基因表达程序（R00）。阐明Nodal信号在体内的功能也可能 对医学有影响，因为Nodal信号传导的失调可以导致出生缺陷和癌症， 人类最后，了解Nodal信号传输精确指令的机制将有助于 通知组织工程和再生生物学，因为Nodal用于控制体外细胞分化。 我的职业目标是管理一个学术实验室，研究发育中的胚胎如何在发育过程中实现精确的模式化。 面对意想不到的干扰。这些实验将给我带来胚胎学方面的经验， 斑马鱼遗传学和光遗传学是实现这一目标所必需的。我已经制定了详细的培训计划， 导师亚历山大希耶博士帮助我过渡到独立。我将定期与希耶博士会面， 讨论研究进展、申请资助的策略、学生指导和实验室管理。练习 我的指导技能，我将监督一个研究生的工作。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， 哈佛的Zon和Ramanathan小组。为了寻求更多的指导，我召集了一个K99咨询公司， 委员会由Adam Cohen博士、Allon Klein博士和Sean Megason博士组成。方面的专门知识 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一员， 接触发育生物学、生物物理学和遗传学领域的领导者，以及尖端的核心设施。 独立之路奖将提供启动雄心勃勃的计划所需的时间和自由。 研究计划的机制，强大的图案在发展中的胚胎。