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: 10625436
• 负责人: Darius Ebrahimi-Fakhari
• 金额: $ 23.13万
• 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/10625436
• 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; Loss of Heterozygosity; 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; Vertebral column; Vesicle; Western Blotting; Wheelchairs; Work; Zebrafish; age related; axonal degeneration; 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.

遗传性痉挛截瘫(HSP)是一组80多种神经退行性疾病，其中 遗传性痉挛和相关残疾的常见原因。这份K08建议书侧重于原型 儿童过敏性紫斑狼疮由四个基因双等位功能丧失变异引起，这些基因编码 接头蛋白复合体4(AP-4)：AP4B1、AP4M1、AP4E1和AP4S1。进行性退行性变 皮质脊髓束导致大多数10岁前患有AP-4相关HSP轮椅的儿童依赖 好几年了。目前，还没有阻止疾病进展的治疗方法，也很少有已知的患者有 活到成年，突显了研究过敏性紫杉醇基础生物学的紧迫性。 AP-4复合体对于跨膜蛋白的细胞内运输至关重要，包括 自噬相关蛋白ATG9A。ATG9A的改变如何导致神经发育受损和 轴突变性和ATG9A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缺乏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的蛋白质运输。在初步实验中，我们系统地筛选出了 用基于细胞的表型分析测定ATG9A的ATG9A转运的分子调节剂 分布作为AP-4功能的替代。我们确定了ATG9A分布的几个调节子。我要测试一下 在AP-4-HSP来源的神经元中恢复ATG9A体外转运和功能的假说 患者和体内的ap4b1-/-斑马鱼模型。 本提案提出了一项为期五年的研究职业发展计划，重点是研究HSP中的AP-4 为了扩大对蛋白质运输和自噬在这一组中作用的理解的广度和深度 疾病。目标是建立一个跨组织的筛选平台，以识别和开发新的 治疗过敏性紫斑狼疮的蛋白质转运调节剂。 这位候选人目前是波士顿儿童医院神经科儿童神经科的住院医生。 医院和哈佛医学院。概述的提案建立在候选人之前对 蛋白质运输、自噬和神经退化，并整合了细胞生物学的新专业领域， 先进的显微镜，以及IPSC衍生的神经元和转基因斑马鱼来模拟人类 疾病。这些技能反映在他的指导团队中，该团队由主要导师穆斯塔法·沙欣博士和 由克雷格·布莱克斯通博士、托马斯·施瓦茨博士、安娜普娜·波杜里博士组成的科学咨询委员会 还有伦纳德·宗博士。拟议的实验和教学工作将为候选人提供一个独特的 一套跨学科的技能，使他能够过渡到作为一名该领域的内科科学家的独立 翻译神经科学在儿童期起病神经疾病中的作用。