Development of a Translational Research Platform to Understand and treat Defective Protein Trafficking in Childhood-Onset Hereditary Spastic Paraplegia

开发转化研究平台以了解和治疗儿童遗传性痉挛性截瘫中的缺陷蛋白贩运

• 批准号: 10284159
• 负责人: Darius Ebrahimi-Fakhari
• 金额: $ 19.6万
• 依托单位: BOSTON CHILDREN'S HOSPITAL
• 依托单位国家: 美国
• 财政年份: 2021
• 资助国家: 美国
• 起止时间: 2021-07-01 至 2026-04-30
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10284159
• 关键词: 10 year old; Adaptor Protein Complex Subunits; Adaptor Signaling Protein; Address; Adult; Advisory Committees; Affect; Autophagocytosis; Autophagosome; Axon; Behavior assessment; Biological Assay; Biology; Boston; Brain; CRISPR/Cas technology; Cells; Cellular biology; Child; Childhood; Complex; Corticospinal Tracts; Development; Disease; Disease Progression; Disease model; Fibroblasts; Fluorescence; Foundations; Future; Genes; Genetic Engineering; Genetic Models; Goals; Hereditary Spastic Paraplegia; Human; Image; Immunohistochemistry; Impairment; In Vitro; Individual; Induced pluripotent stem cell derived neurons; Inherited; Integral Membrane Protein; Label; Larva; Lead; LysoTracker; Lysosomes; Measures; Mediating; Mentors; Microscopy; Modeling; Morphology; Motor; Motor Neurons; Nerve Degeneration; Neurites; Neurodegenerative Disorders; Neurology; Neurons; Pathway interactions; Patients; Pediatric Hospitals; Pediatric Neurology; Phenotype; Physicians; Positioning Attribute; Program Development; Proteins; Research; Role; Scientist; Simvastatin; Spinal; Stains; Starvation; Survival Analysis; TFAP2A gene; Testing; Training; Transcription Factor AP-1; Translational Research; Variant; Vesicle; Western Blotting; Wheelchairs; Work; Zebrafish; age related; axonal degeneration; base; behavior test; career; career development; disability; experimental study; human disease; human model; in vivo; induced pluripotent stem cell; knock-down; loss of function; medical schools; molecular phenotype; motor deficit; nervous system disorder; neurodevelopment; neuronal cell body; novel; protein complex; protein phosphatase inhibitor-2; protein transport; restoration; screening; skills; small molecule; spasticity; trafficking; trans-Golgi Network; translational neuroscience; translational pipeline

The hereditary spastic paraplegias (HSP) are a group of over 80 neurodegenerative conditions and the most common cause of inherited spasticity and associated disability. This K08 proposal focuses on prototypical forms of HSP in children caused by biallelic loss-of-function variants in four genes that encode subunits of the adaptor protein complex 4 (AP-4): AP4B1, AP4M1, AP4E1, and AP4S1. Progressive degeneration of the cortico-spinal tracts renders most children with AP-4-associated HSP wheelchair-dependent by the age of 10 years. Currently, there are no therapies that halt disease progression, and few patients are known to have survived into adulthood, highlighting the urgency for research into the fundamental biology of HSP. The AP-4 complex is crucial for the intracellular trafficking of transmembrane proteins, including the autophagy-related protein ATG9A. How altered trafficking of ATG9A leads to impaired neurodevelopment and axonal degeneration and how ATG9A distribution can be restored is currently unknown. In this proposal, I will address this unmet question by developing neuronal models of AP-4 deficiency and testing novel modulators of AP-4-dependent protein trafficking. In preliminary experiments, we have systematically screened small molecule modulators of ATG9A trafficking using a cell-based phenotypic assay that measures ATG9A distribution as a surrogate of AP-4 function. We identified several modulators of ATG9A distribution. I will test the hypothesis that these restore trafficking and function of ATG9A in vitro in neurons derived from AP-4-HSP patients and in vivo in an ap4b1-/- zebrafish model. This proposal presents a five-year research career development program focused on the study of AP-4 in HSP to expand the breadth and depth of understanding the role of protein trafficking and autophagy in this group of diseases. The goal is the establishment of a cross-organismal screening platform to identify and develop novel modulators of protein trafficking for the treatment of HSP. The candidate is currently a resident in Child Neurology at the Department of Neurology at Boston Children's Hospital and Harvard Medical School. The outlined proposal builds on the candidate's previous research on protein trafficking, autophagy and neurodegeneration and integrates new domains of expertise in cell biology, advanced microscopy, and iPSC-derived neurons and genetically-engineered zebrafish to model human diseases. These skills are reflected in his mentoring team consisting of primary mentor, Dr. Mustafa Sahin, and a scientific advisory committee consisting of Dr. Craig Blackstone, Dr. Thomas Schwarz, Dr. Annapurna Poduri and Dr. Leonard Zon. The proposed experiments and didactic work will position the candidate with a unique set of cross-disciplinary skills that will enable his transition to independence as a physician-scientist in the field of translational neuroscience in childhood-onset neurological diseases.

遗传性痉挛性截瘫（HSP）是一组超过80种神经退行性疾病， 遗传性痉挛和相关残疾的常见原因。本K 08提案侧重于原型 儿童中HSP的形式是由编码HSP亚单位的四个基因中的双等位基因功能丧失变体引起的。 衔接蛋白复合物4（AP-4）：AP 4 B1、AP 4 M1、AP 4 E1和AP 4S 1。进行性变性 皮质脊髓束使大多数患有AP-4相关HSP的儿童在10岁时依赖轮椅 年目前，没有阻止疾病进展的疗法，并且已知很少有患者具有 存活到成年，突出了对HSP基础生物学研究的紧迫性。 AP-4复合物对于跨膜蛋白的细胞内运输至关重要，包括 自噬相关蛋白ATG 9A。ATG 9A的改变如何导致神经发育受损， 轴突变性和ATG 9A分布如何恢复目前尚不清楚。在这份提案中，我将 通过开发AP-4缺陷的神经元模型和测试新的调节剂来解决这个未解决的问题 依赖AP-4的蛋白运输。在初步实验中，我们系统地筛选了小 使用测量ATG 9A的基于细胞的表型测定的ATG 9A运输的分子调节剂 作为AP-4功能的替代物。我们鉴定了几种ATG 9A分布的调节剂。我将测试 假设这些物质在体外恢复了来源于AP-4-HSP的神经元中ATG 9A的运输和功能 患者和在体内在AP 4 B1-/-斑马鱼模型中。 该提案提出了一个为期五年的研究职业发展计划，重点是HSP中AP-4的研究 扩大理解蛋白质运输和自噬在这组中的作用的广度和深度。 疾病目标是建立一个跨生物体筛选平台，以识别和开发新的 用于治疗HSP的蛋白质运输调节剂。 候选人目前是波士顿儿童医院神经病学系儿童神经病学的住院医师。 医院和哈佛医学院。概述的建议建立在候选人以前的研究基础上， 蛋白质运输，自噬和神经变性，并整合了细胞生物学的新领域的专业知识， 先进的显微镜，iPSC衍生的神经元和基因工程改造的斑马鱼，以模拟人类 疾病这些技能反映在他的指导团队中，该团队由主要导师Mustafa Sahin博士和 一个科学顾问委员会，由克雷格黑石博士、托马斯施瓦茨博士、安娜普尔纳·波杜里博士 和伦纳德·佐恩医生拟议的实验和教学工作将定位候选人与一个独特的 一套跨学科的技能，这将使他过渡到独立作为一个物理学家，科学家在该领域 儿童期神经系统疾病的转化神经科学。