Regulation of Neurogenesis in TSC by mTORC1 and mTORC2

mTORC1 和 mTORC2 对 TSC 神经发生的调节

• 批准号: 8473929
• 负责人: KEVIN C ESS
• 金额: $ 32.9万
• 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/8473929
• 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.

描述（由申请人提供）：结节性硬化症复合物（TSC）是由TSC1或TSC2基因突变引起的遗传疾病。患者经常患有严重的中枢神经系统表现，包括癫痫，智力障碍和自闭症。 TSC患者大脑中的皮质畸形（“块茎”）通常被接受为这些严重的神经系统表现。先前使用人体组织和转基因小鼠和斑马鱼模型的研究使我们对神经祖细胞/干细胞的关注。神经祖细胞的异常可以很容易地解释了TSC患者大脑中看到的细胞数量增加，非典型分化和神经元的异位位置。尽管对MTOR激酶的控制似乎最关键，但已知几种信号通路在TSC中失调。最近的发现支持MTOR在两个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MTORC2信号传导降低。然而，在TSC发病机理期间，MTORC1和MTORC2信号的相对贡献仍然鲜为人知。该提案的总体目标是确定MTORC1和MTORC2信号在TSC发病机理中的作用。该目标通过寻求提高我们对正常大脑和神经系统的发展，这些过程在疾病中如何颠覆以及这些信息是否可以更好地治疗神经系统疾病的知识来直接解决NINDS战略计划。为了实现这一目标，我们将使用两种转基因小鼠模型，包括小鼠TSC1基因失活以及诱导的多能干细胞（IPSC），我们由于TSC1或TSC2基因功能突变的丧失而产生了TSC患者。小鼠和人神经祖细胞的直接比较是该提案的关键方面，因为在进化过程中可能会出现大脑MTOR信号传导的基本差异。 该项目的具体目的是1）确定TSC1/2-突变的人和TSC1缺陷的小鼠神经祖细胞是否会产生过多的神经元； 2）确定从TSC1缺陷和TSC2缺陷的人和TSC1缺陷的小鼠神经祖细胞产生的神经元是否能够获得下层或上层身份，以及MTORC1信号的抑制是否可以恢复这些身份； 3）。确定单独的MTORC2信号是否足以引起小鼠和人神经祖细胞的异常分化。 这些研究应大大增加我们对小鼠TSC1和人类TSC基因功能的理解。我们的建议有望定义小鼠和人类细胞中MTORC1和MTORC2信号通路异常，并导致为TSC患者开发更有效的疗法。