Oculomotor axon guidance in normal and abnormal development

动眼神经轴突引导正常和异常发育

• 批准号: 9294745
• 负责人: Mary Catherine Whitman
• 金额: $ 21.61万
• 依托单位: BOSTON CHILDREN'S HOSPITAL
• 依托单位国家: 美国
• 财政年份: 2017
• 资助国家: 美国
• 起止时间: 2017-07-01 至 2020-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/9294745
• 关键词: AMD3100; Address; Advisory Committees; Affect; Area; Axon; Biological; Biological Assay; Boston; Brain Stem; CXCL12 gene; CXCR4 Receptors; CXCR4 gene; Candidate Disease Gene; Categories; Cell Nucleus; Cell Surface Receptors; Cephalic; Childhood; Clinical; Collaborations; Complex; Culture Media; Data; Defect; Development; Diagnosis; Disease; Dorsal; Ear; Embryo; Environment; Eye; Eye Movements; Fiber; Fibrosis; Genes; Genetic; Genetic Transcription; Goals; Growth; Growth Factor Receptors; Human; Image; Individual; Institutes; Ion Channel; Knockout Mice; Knowledge; Lead; Ligands; Massachusetts; Mentors; Mentorship; Midbrain structure; Molecular; Motor; Motor Neurons; Mus; Mutation; Natural regeneration; Nerve; Neurodegenerative Disorders; Neurodevelopmental Disorder; Neurotransmitter Receptor; Ocular Motility Disorders; Ocular orbit; Oculomotor nerve structure; Ophthalmologist; Ophthalmoplegia; Paralysed; Pathogenicity; Pathway interactions; Patients; Pattern; Pediatric Hospitals; Productivity; Program Development; Ptosis; Research; Resources; Role; SECTM1 gene; Scientist; Series; Signal Pathway; Signal Transduction; Slice; Strabismus; Synapses; System; Testing; Time; Training; Training Programs; Trigeminal System; Validation; Variant; Vision; axon growth; axon guidance; base; career; career development; chemokine receptor; cohort; genetic pedigree; genome sequencing; improved; in vitro Assay; in vivo; inhibitor/antagonist; medical schools; meetings; mouse model; nerve supply; novel; oculomotor; orbit muscle; programs; receptor; research and development; screening; small molecule inhibitor; software development; whole genome

This proposal describes a 3-year training program for the development of an academic career focused on understanding the molecular mechanisms of strabismus and ocular motility disorders. I am a pediatric ophthalmologist at Boston Children's Hospital (BCH) and Harvard Medical School (HMS), currently training in the Harvard Vision Clinical Scientist Development Program (K12). I wish to continue my research and career development to prepare for an independent research career. My long-term goals include understanding the molecular basis of complex strabismus, elucidating fundamental mechanisms of axon guidance, and ultimately devising new treatments for strabismus and ocular motility disorders, such as aberrant regeneration. The proposed research program focuses on identifying new molecular pathways important for axon guidance of the oculomotor nerve and additional genetic causes of Congenital Fibrosis of the Extraocular Muscles (CFEOM). Dr. Elizabeth Engle will serve as mentor. She is a world expert on the development of the oculomotor system and has a proven track record of productivity and mentorship. An advisory committee including David Hunter, Daniel MacArthur, and Larry Benowitz will guide my research and career development. The project will take place in the rich research environment of BCH, with access to the resources of HMS, Massachusetts Eye and Ear Infirmary, and the Broad Institute. There are extensive opportunities to attend and present at lab meetings, departmental seminars, national meetings, and didactic courses. The first experimental approach uses a novel midbrain-orbit embryonic slice assay I developed, in which the developing oculomotor nerve is time-lapse imaged as it grows towards the orbit. To identify signaling pathways important in oculomotor growth and guidance the cultures are treated with small molecule inhibitors of cell- surface receptors. Candidate receptors will be chosen based on transcriptional profiling of motor neurons at E10.5 and E11.5 (unpublished data). The role of molecules that perturb guidance in the slice assay will be defined in vivo by examining mouse models for axon guidance defects and aberrant innervation. Proof of concept has been established using an inhibitor of CXCR4 signaling, AMD3100. Preliminary data in vivo confirms oculomotor axon growth dorsally rather than ventrally, and this pathway will be further examined. The second approach seeks to relate these findings to human disorders of ocular motility, particularly CFEOM. Whole genome sequencing (WGS) is underway on 48 pedigrees with genetically unsolved CFEOM, and will be analyzed in collaboration with Daniel MacArthur's team at the Broad Institute. Variants in pathways that perturb axon guidance in the slice assay will be prioritized in the analysis. Conversely, variants identified in the WGS will be tested in the slice assay to help determine pathogenicity. Through these approaches, we will identify new pathways important in axon guidance, opening new areas of research. The proposal addresses an understudied area of clinical need while preparing me for a successful career as a clinician-scientist.

该提案描述了一个为期3年的培训计划，以发展学术生涯为重点， 了解斜视和眼球运动障碍的分子机制。我是一名儿科医生 波士顿儿童医院（BCH）和哈佛医学院（HMS）的眼科医生，目前正在接受 哈佛视觉临床科学家发展计划（K12）。我希望继续我的研究和事业 为独立的研究生涯做准备。我的长期目标包括了解 复杂性斜视的分子基础，阐明轴突导向的基本机制，并最终 为斜视和眼球运动障碍（如异常再生）设计新的治疗方法。 拟议的研究计划的重点是确定新的分子途径重要的轴突指导 眼外肌先天性纤维化的其他遗传原因 （CFEOM）。伊丽莎白·恩格尔博士将担任导师。她是一位世界级的专家， 我们拥有一套专业的培训系统，并在生产力和指导方面有良好的记录。一个咨询委员会 包括大卫亨特、丹尼尔麦克阿瑟和拉里本诺维茨将指导我的研究和职业发展。 该项目将在BCH丰富的研究环境中进行，可以访问HMS的资源， 马萨诸塞州眼耳医院和布罗德研究所。有大量的机会参加， 出席实验室会议，部门研讨会，国家会议和教学课程。 第一种实验方法使用了我开发的一种新颖的中脑-眼眶胚胎切片测定法， 发育中的眼神经在向眼眶生长时被延时成像。来识别信号通路 在眼的生长和引导中重要的是，用细胞的小分子抑制剂处理培养物， 表面受体候选受体将基于运动神经元的转录谱来选择， E10.5和E11.5（未发表的数据）。在切片测定中干扰引导的分子的作用将是 通过检查轴突导向缺陷和异常神经支配的小鼠模型在体内定义。证明 已经使用CXCR 4信号传导抑制剂AMD 3100建立了概念。体内初步数据 证实了眼神经轴突的生长是从背侧而不是腹侧，这一途径将被进一步研究。 第二种方法试图将这些发现与人类的眼球运动障碍联系起来， CFEOM。全基因组测序（WGS）正在对48个遗传学上未解决的CFEOM家系进行， 并将与布罗德研究所的丹尼尔麦克阿瑟团队合作进行分析。途径中的变体 在切片测定中扰乱轴突引导的那些将在分析中优先考虑。相反地， WGS将在切片测定中进行测试以帮助确定致病性。通过这些方法，我们将 确定轴突指导中重要的新途径，开辟新的研究领域。该提案针对一个 在为我作为一名临床科学家的成功职业生涯做准备的同时，我对临床需求的研究不足。