The role of the protocadherin gene cluster in neurodevelopment and the implications for neurodevelopmental disorders

原钙粘蛋白基因簇在神经发育中的作用及其对神经发育障碍的影响

• 批准号: 10808516
• 负责人: Erin Flaherty
• 金额: $ 13.17万
• 依托单位: COLUMBIA UNIVERSITY HEALTH SCIENCES
• 依托单位国家: 美国
• 财政年份: 2023
• 资助国家: 美国
• 起止时间: 2023-09-05 至 2025-08-31
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10808516
• 关键词: Address; Award; Behavior; Biological; Biophysics; Brain; Cell Nucleus; Cell membrane; Cells; Cellular Assay; Chromatin; Complex; Cytoplasm; Data; Development; Dimerization; Disease; Disease model; Etiology; Evaluation; Event; Faculty; Feedback; Foundations; GTP-Binding Proteins; Gene Cluster; Gene Expression; Genes; Genetic; Genetic Transcription; Goals; Human; In Vitro; Individual; Institution; Integral Membrane Protein; Knowledge; Laboratories; Learning; Link; Lymphocyte; Mammals; Mediating; Membrane; Mentors; Mentorship; Microfilaments; Modeling; Molecular; Movement; Mus; Needs Assessment; Neurites; Neurodevelopmental Disorder; Neurons; Nuclear; Organoids; Patients; Phase; Positioning Attribute; Postdoctoral Fellow; Process; Protein Isoforms; Proteins; Research; Role; Schizophrenia; Scientist; Series; Signal Pathway; Signal Transduction; Single Nucleotide Polymorphism; Sister; Structure; Surface; Synapses; Synaptic Transmission; Techniques; Tertiary Protein Structure; Testing; Training; Transcriptional Regulation; Variant; Vertebrates; WNT Signaling Pathway; Work; autism spectrum disorder; axon guidance; gene function; genetic approach; in vivo; in vivo Model; induced pluripotent stem cell; insight; membrane biogenesis; neural; neural circuit; neurodevelopment; neuronal circuitry; neuropsychiatric disorder; notch protein; novel; proband; protein function; screening; synaptogenesis

PROJECT SUMMARY During development, individual neurons extend highly branched neurites that innervate the surrounding territory with minimal overlap. In mammals, the clustered protocadherins (Pcdh) provide each neuron with a unique cell specific identity required for self-identification and self-avoidance in the brain. Individual PCDHa/b/g protein isoforms cis-dimerize, and engage in homophilic trans interactions to create a lattice-like structure at contacting membrane surfaces, providing the diversity required for self-recognition. Deletion of Pcdh genes in mice results in deficits in neuronal wiring and altered behaviors. Biophysical and structural data, cellular assays, and functional studies support a model in which perfect homophilic matching of PCDH isoforms leads to the assembly of an extended PCDH lattice structure on sister neurites, triggering intracellular signaling, and a series of yet to be identified steps leading to self-avoidance. Many neuronal transmembrane proteins execute neurodevelopmental processes through both nuclear and membrane associated signaling mechanisms; however, the mechanisms regulating PCDH mediated self-avoidance remain unknown. My recent work in the Maniatis lab has demonstrated that the PCDHa/g intracellular domain (ICDs) are required for interactions with protein partners at the membrane (e.g. WAVE complex and WNT signaling modulators) and in the nucleus (e.g. chromatin and transcriptional regulators). In the nucleus, the PCDH-ICD interacts with and may regulate the expression of genes involved in axon guidance, synapse formation and participate in an auto-regulatory feedback loop. During the K99 phase, I will leverage these preliminary findings to assess the need for each downstream signaling mechanism for proper self-avoidance in vitro (Aim 1) and in vivo (Aim 2). During the independent R00 phase, I will implement knowledge and techniques acquired in the mentored phase to investigate whether PCDH SNVs from ASD cases disrupt the identified downstream signaling mechanisms, proper self-avoidance and neural circuitry during development (Aim 3). Understanding the mechanisms of self-avoidance is a fundamental step toward revealing how neural circuits are formed during development in vertebrates and could have important implications for neurodevelopmental disorders. The work described in the mentored portion of this proposal will be conducted under the mentorship of Dr. Maniatis, who has a strong record of mentoring postdoctoral research scientists who have transitioned into their own laboratories. Ultimately, this award will allow me to accomplish three broad training goals including; (1) learning to address biological questions using in vivo models, (2) developing and extending my knowledge of molecular and genetic approaches to probe gene function, and (3) expanding on my background in iPSC based disease modeling by probing PCDH function in cortical organoids. Achieving these goals and training will provide me with the strong foundation required to pursue a faculty position at a research institution where I can integrate in vitro and in vivo approaches to investigate novel questions in the field of neurodevelopment.

项目摘要 在发育过程中，单个神经元延伸出高度分支的神经突， 领土重叠最少。在哺乳动物中，成簇的原钙粘蛋白（Pcdh）为每个神经元提供了一个 大脑中自我识别和自我回避所需的独特细胞特异性身份。单个多氯二苯甲烷a/B/g 蛋白质异构体顺式二聚化，并参与同亲性反式相互作用，以产生晶格状结构， 接触膜表面，提供自我识别所需的多样性。Pcdh基因的缺失 小鼠导致神经元布线缺陷和行为改变。生物物理和结构数据，细胞 分析和功能研究支持一种模型，其中PCDH同种型的完美同型匹配导致 延伸的PCDH晶格结构在姐妹神经突上的组装，触发细胞内信号传导，以及 一系列尚未确定的步骤导致自我回避。许多神经元跨膜蛋白执行 通过核和膜相关信号机制的神经发育过程; 然而，调节PCDH介导的自我回避的机制仍然未知。 我最近在Maniatis实验室的工作表明，PCDHa/g胞内结构域（ICD）是 在膜上与蛋白质伴侣相互作用所需的（例如WAVE复合物和WNT信号传导 调节子）和细胞核（例如染色质和转录调节子）中。在细胞核中，PCDH-ICD 与参与轴突引导、突触形成和突触形成的基因相互作用并可调节其表达， 参与自动调节反馈回路。在K99阶段，我将利用这些初步发现 为了评估每种下游信号传导机制在体外（目标1）和体外（目标2）中正确自我回避的必要性， 体内（目标2）。在独立R 00阶段，我将实施在 指导阶段，以调查ASD病例的PCDH SNV是否破坏已确定的下游 信号机制，适当的自我回避和神经回路在发展过程中（目标3）。理解 自我回避的机制是揭示神经回路如何形成的基本步骤 在脊椎动物的发育过程中，可能对神经发育障碍有重要影响。 本建议书的指导部分所述的工作将在博士的指导下进行。 Maniatis在指导博士后研究科学家方面有着良好的记录，这些科学家已经过渡到 自己的实验室。最终，这个奖项将使我能够实现三个广泛的培训目标，包括： (1)学习使用体内模型解决生物学问题，（2）发展和扩展我的知识 分子和遗传学方法来探测基因功能，（3）扩展我在iPSC方面的背景 通过探测皮质类器官中的PCDH功能来建立疾病模型。实现这些目标和培训 将为我提供所需的强大的基础，在一个研究机构，我追求教师的位置， 可以整合体外和体内方法来研究神经发育领域的新问题。