Molecular Development and Diversity of Callosal Projection Neurons

胼胝体投射神经元的分子发育和多样性

• 批准号: 10558466
• 负责人: JEFFREY D MACKLIS
• 金额: $ 39万
• 依托单位: HARVARD UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2020
• 资助国家: 美国
• 起止时间: 2020-03-15 至 2025-01-31
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10558466
• 关键词: Area; Axon; Behavior; Behavior Disorders; Behavioral; Brain; Cells; Cerebral cortex; Cerebral hemisphere; Cognition; Cognitive; Complex; Corpus Callosum; Development; Developmental Biology; Diagnosis; Disease; Electroporation; Evolution; Exhibits; Functional disorder; Future; Gene Expression; Gene Expression Regulation; Generations; Genes; Genetic Transcription; Goals; Growth Cones; Human; Individual; Intellectual functioning disability; Investigation; Knowledge; Label; Link; Location; Maps; Mental disorders; Molecular; Motor; Mus; Nature; Neocortex; Neurons; Parents; Persons; Phenotype; Plasmids; Play; Population; Population Analysis; Positioning Attribute; Prevention; Process; Proteins; Proteome; Proteomics; Publishing; RNA; Regulation; Research; Role; Schizophrenia; Sensory; Somatosensory Cortex; Specific qualifier value; Structure; System; Technology; Therapeutic; Time; Transcriptional Regulation; Visualization; Work; autism spectrum disorder; axon growth; behavior test; behavioral phenotyping; candidate validation; combinatorial; developmental disease; gain of function; genetic analysis; genetic manipulation; hippocampal pyramidal neuron; human disease; in utero; innovation; insight; interest; mosaic; mosaic analysis; neocortical; neuron development; neuronal cell body; neuronal circuitry; neuronal growth; novel; novel strategies; postmitotic; prevent; progenitor; programs; recombinase; somatosensory; tool; transcriptomics

The long-term goals of the proposed research are both to elucidate central molecular controls over development and diversity of neocortical callosal projection neuron (CPN) connectivity, and to identify potential causes and therapeutic approaches to disease involving CPN circuitry. CPN are the broad population of inter-hemispheric pyramidal neurons whose axons connect the two cerebral hemispheres via the corpus callosum. CPN play key roles in high-level associative, integrative, cognitive, behavioral, sensory, and motor functions, based on precise, area-specific CPN subtype connectivity and diversity. Disruptions in CPN development are correlated with deficits in multiple disorders, including agenesis of the corpus callosum, autism spectrum disorders, and schizophrenia. Currently, how the remarkable diversity of CPN subtypes and connectivity is specified, and how transcriptional programs implement specific connectivity via local, cell-autonomous effectors, is unknown. Our lab recently identified a combinatorially-expressed set of genes that both define CPN as a broad population, and identify novel subpopulations of CPN during development (Neuron, 2005, 2016a,b; J Neurosci, 2009; Cer Cor, 2016a,b). We also developed innovative approaches to investigate subtype-specific, subcellular growth cone (GC) molecular machinery. Building on this work, we propose deep and rigorous functional investigation of Cited2 control over precise CPN connectivity & circuit wiring, including RNAs & proteins detected uniquely in GCs. Cited2 is an exemplar transcriptional co-regulator that we hypothesize functions importantly in development of precise areally- and functionally-specific CPN circuitry in somatosensory cortex, and its dysfunction elucidates disorders of CPN connectivity and diversity. We have already identified that Cited2 regulates and refines two stages of precise CPN development and diversity, functioning 1) broadly in basal progenitors to regulate generation of superficial layer CPN, and 2) postmitotically in an area-restricted manner to refine distinct, precise identity and development of somatosensory (S1) CPN. To connect Cited2 transcriptional regulation to local implementation of S1 CPN connectivity in developing GCs, we propose to: Aim 1) investigate CPN-autonomy of Cited2 regulatory function in S1 CPN postmitotic development and connectivity, via novel mosaic, recombinase-based genetic manipulation technology (“BEAM”) for dual population analysis; Aim 2) investigate GC & soma RNA & proteomes of WT vs Cited2 cKO S1 CPN during axon development via new and innovative approaches, to gain direct mechanistic understanding of CPN circuit development at critical developmental stages; Aim 3) investigate the specific function of GC-localized downstream effectors that are dysregulated in Cited2-null CPN; and Aim 4) investigate the integrated function of precise CPN circuit development in cognitive & ASD-relevant behavior. Together, the proposed studies will provide substantial insight from gene to circuit to behavior into molecular control over development, diversity, and precision of connectivity of CPN subtypes with distinct function and integration of cortical information, processes centrally disrupted in human disorders. Controls over CPN connectivity are now essentially unknown, and transcriptional dysregulation has not been previously connected to downstream local effectors of circuit development. This research will contribute to understanding cortical organization, function, and potentially toward prevention, diagnosis, and therapy of human disorders.

拟议的研究的长期目标既阐明了中央分子控制的发展和 新皮质callosal投射神经元（CPN）连通性的多样性，并确定潜在的原因和治疗 涉及CPN电路的疾病方法。 CPN是丘脑间锥体神经元的广泛种群 轴突通过call体连接两个脑半球。 CPN基于精度，特定于区域的CPN亚型连接性和多样性，在高级关联，集成，认知，行为，感觉和运动功能中扮演关键角色。 CPN发育中的破坏与多种疾病的定义相关，包括call体的发育不全，自闭症谱系障碍和精神分裂症。当前，如何指定CPN子类型和连接性的显着多样性，以及转录程序如何通过局部，细胞自主效应实现特定的连通性。我们的实验室最近确定了一组组合表达的基因集，这些基因既将CPN定义为广泛的人群，又确定了开发过程中CPN的新型亚群（Neuron，2005，2016a，b; J Neurosci，2009; Cor Cor，Cor，2016a，2016a，b）。我们还开发了创新的方法来研究亚型特异性亚型亚细胞生长锥（GC）分子机械。在这项工作的基础上，我们提出了对Precision CPN连通性和电路接线的深入而严格的功能投资，包括在GC中唯一检测到的RNA和蛋白质。 CITED2是一种示例性转录共同调节器，我们假设在体感皮质中的精确和功能特定的CPN电路中重要地提出功能，并且其功能障碍阐明了CPN连接性和多样性的疾病。 我们已经确定，引用2的调节和完善了精确CPN发展和多样性的两个阶段， 1）在基本的祖细胞中广泛调节表面层CPN的产生，2）以区域限制的方式进行森林观念，以优化不同的，精确的身份和体感（S1）CPN的发展。为了将引用2的转录调控与开发GC中的S1 CPN连接的局部实施，我们建议：目标1）通过新型的Mosaic，基于重物组织酶的基于重物组织酶的遗传操纵技术（“ Beam”）研究S1 CPN的MOSAIMITOTIOT开发和连接性的CPN Autonomy2在S1 CPN的MOSAIMITOTION发育和连接性中的调节功能，以进行双重种群分析；目标2）通过新的和创新的方法研究轴突开发过程中WT与引用的2 CKO S1 CPN的GC和SOMA RNA和蛋白质组织，以在关键发展阶段获得对CPN电路开发的直接机械理解； AIM 3）研究GC位定位的下游效应的特定功能，这些效应在引用2-null CPN中失调；目标4）研究认知和与ASD相关的行为中精确CPN电路发展的综合功能。共同的研究将提供从基因到电路再到行为的实质性见解，以分子控制CPN亚型的发育，多样性以及具有独特功能和皮质信息整合的连通性的精度，这些过程在人类疾病中集中破坏。现在，对CPN连接性的控制基本上是未知的，并且转录失调以前尚未连接到电路发展的下游局部效应。这项研究将有助于理解皮质组织，功能以及潜在的人类疾病的预防，诊断和治疗。