Regulation of Neurogenesis in TSC by mTORC1 and mTORC2

mTORC1 和 mTORC2 对 TSC 神经发生的调节

• 批准号: 8399444
• 负责人: KEVIN C ESS
• 金额: $ 34.1万
• 依托单位: VANDERBILT UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2012
• 资助国家: 美国
• 起止时间: 2012-06-01 至 2017-05-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8399444
• 关键词: Abate; Accounting; Address; Animal Model; Autistic Disorder; Basic Science; Brain; Cell Count; Cell Differentiation process; Cell Proliferation; Cells; Cerebral cortex; Child; Clinical; Complex; Cortical Malformation; Development; Disease; Embryonic Development; Epilepsy; Evolution; Functional disorder; Genes; Genetic Heterogeneity; Goals; Health; Hereditary Disease; Human; Intellectual functioning disability; Knowledge; Lead; Modality; Modeling; Molecular; Mus; National Institute of Neurological Disorders and Stroke; Neuroglia; Neurologic; Neurologic Manifestations; Neuronal Differentiation; Neurons; Outcome; Pathogenesis; Pathway interactions; Patients; Phosphotransferases; Positioning Attribute; Process; Production; Protein-Serine-Threonine Kinases; Regulation; Relative (related person); Research; Role; Signal Pathway; Signal Transduction; Sirolimus; Stem cells; Strategic Planning; Symptoms; TSC1 gene; TSC1/2 gene; TSC2 gene; Therapeutic; Transgenic Mice; Translating; Translational Research; Tuberous sclerosis protein complex; Work; Zebrafish; base; brain malformation; clinical efficacy; disease-causing mutation; effective therapy; excitatory neuron; gene function; human FRAP1 protein; human TSC1 protein; human TSC2 protein; human tissue; induced pluripotent stem cell; inhibitor/antagonist; innovation; insight; loss of function; loss of function mutation; mTOR inhibition; mTOR protein; migration; mouse model; mutant; nerve stem cell; nervous system disorder; neurodevelopment; neurogenesis; novel; patient population; prevent; programs; protein complex; research study

DESCRIPTION (provided by applicant): Tuberous Sclerosis Complex (TSC) is a genetic disease caused by mutation of the TSC1 or TSC2 genes. Patients frequently have severe CNS manifestations including epilepsy, intellectual disabilities and autism. Cortical malformations ("tubers") in the brains of patients with TSC are generally accepted as responsible for these severe neurological manifestations. Previous studies using human tissues and transgenic mouse and zebrafish models have led our focus on neural progenitor/stem cells. Abnormalities of neural progenitor cells may readily explain the increased cell number, atypical differentiation and ectopic position of neurons seen within the brain of patients with TSC. Several signaling pathways are known to be dysregulated in TSC though control of the mTOR kinase appears most critical. Recent findings support abnormalities of mTOR within two distinct protein complexes, mTORC1 and mTORC2. These alterations differ as we have found that Tsc1- deficient mouse neural progenitor cells appear to have increased mTORC1 but decreased mTORC2 signaling. However, the relative contribution of mTORC1 and mTORC2 signaling during the pathogenesis of TSC remains poorly understood. The overarching goal of this proposal is to determine the role of mTORC1 and mTORC2 signaling in the pathogenesis of TSC. This goal directly addresses the NINDS Strategic Plan by seeking to increase our knowledge of how the normal brain and nervous system develop, how these processes are subverted in disease and whether this information can lead to better treatments of neurological disorders. To achieve this goal we will use both transgenic mouse models featuring the inactivation of the mouse Tsc1 gene as well as induced pluripotent stem cells (iPSC) we have generated from patients with TSC due to loss of function mutations of the TSC1 or TSC2 genes. The direct comparison of mouse and human neural progenitor cells is a key aspect of this proposal as fundamental differences in the control of mTOR signaling in the brain likely arose during evolution. The Specific Aims of this project are to 1) Determine if TSC1/2-mutant human and Tsc1-deficient mouse neural progenitor cells generate excessive numbers of neurons; 2) Determine if neurons generated from TSC1-deficient and TSC2-deficient human and Tsc1-deficient mouse neural progenitors are able to acquire lower or upper layer identity and whether inhibition of mTORC1 signaling can restore these identities; 3). Determine if decreased mTORC2 signaling alone is sufficient to cause abnormal differentiation of mouse and human neural progenitor cells. These studies should greatly increase our understanding of the function of the mouse Tsc1 and human TSC genes. Our proposal is expected to define abnormal mTORC1 and mTORC2 signaling pathways in mouse and human cells and lead to the development of much more effective therapies for patients with TSC. PUBLIC HEALTH RELEVANCE: This project directly addresses human health through the study of pathological mechanisms leading to brain malformations, epilepsy and autism in children. The use of transgenic mice and patient derived induced pluripotent stem cells leverages recent advances in basic and translational research for the study of tuberous sclerosis complex. This proposal then is considered to be highly responsive to the 2010 NINDS Strategic Plan: "Understand how the normal brain and nervous system develop and work, and what goes wrong in disease, and Translate basic and clinical discoveries into better ways to prevent and treat neurological disorders".

描述（申请人提供）： 结节性硬化症（TSC）是一种由 TSC1 或 TSC2 基因突变引起的遗传性疾病。患者经常出现严重的中枢神经系统症状，包括癫痫、智力障碍和自闭症。人们普遍认为，TSC 患者大脑中的皮质畸形（“结节”）是造成这些严重神经系统表现的原因。先前使用人体组织以及转基因小鼠和斑马鱼模型的研究使我们将注意力集中在神经祖细胞/干细胞上。神经祖细胞的异常可以很容易地解释 TSC 患者脑内神经元细胞数量增加、非典型分化和异位位置的原因。尽管 mTOR 激酶的控制似乎最为关键，但已知 TSC 中的多种信号传导途径失调。最近的研究结果支持 mTOR 在两种不同的蛋白质复合物（mTORC1 和 mTORC2）中的异常。这些改变有所不同，因为我们发现 Tsc1 缺陷的小鼠神经祖细胞似乎增加了 mTORC1，但减少了 mTORC2 信号传导。然而，mTORC1 和 mTORC2 信号在 TSC 发病机制中的相对贡献仍知之甚少。该提案的总体目标是确定 mTORC1 和 mTORC2 信号传导在 TSC 发病机制中的作用。这一目标直接涉及 NINDS 战略计划，旨在增加我们对正常大脑和神经系统如何发育、这些过程在疾病中如何被破坏以及这些信息是否可以更好地治疗神经系统疾病的了解。为了实现这一目标，我们将使用以小鼠 Tsc1 基因失活为特征的转基因小鼠模型，以及由于 TSC1 或 TSC2 基因功能突变丧失而从 TSC 患者中产生的诱导多能干细胞 (iPSC)。小鼠和人类神经祖细胞的直接比较是该提议的一个关键方面，因为大脑中 mTOR 信号传导的控制可能在进化过程中出现根本差异。 该项目的具体目标是 1) 确定 TSC1/2 突变的人类和 Tsc1 缺陷的小鼠神经祖细胞是否产生过多数量的神经元； 2) 确定由 TSC1 缺陷和 TSC2 缺陷人类以及 Tsc1 缺陷小鼠神经祖细胞生成的神经元是否能够获得下层或上层身份，以及抑制 mTORC1 信号传导是否可以恢复这些身份； 3）。确定仅减少 mTORC2 信号传导是否足以引起小鼠和人类神经祖细胞的异常分化。 这些研究应该会大大增加我们对小鼠 Tsc1 和人类 TSC 基因功能的理解。我们的提案预计将定义小鼠和人类细胞中异常的 mTORC1 和 mTORC2 信号通路，并为 TSC 患者开发更有效的疗法。 公共健康相关性：该项目通过研究导致儿童大脑畸形、癫痫和自闭症的病理机制，直接解决人类健康问题。使用转基因小鼠和患者衍生的诱导多能干细胞利用了基础和转化研究的最新进展来研究结节性硬化症。该提案被认为是对2010年NINDS战略计划的高度响应：“了解正常的大脑和神经系统如何发育和工作，以及疾病中出了什么问题，并将基础和临床发现转化为预防和治疗神经系统疾病的更好方法”。