Thyroid Hormone and Retinoic Acid Regulation of Gene Expression

甲状腺激素和视黄酸对基因表达的调节

• 批准号: 8633738
• 负责人: GREGORY A BRENT
• 金额: --
• 依托单位: VA GREATER LOS ANGELES HEALTHCARE SYSTEM
• 依托单位国家: 美国
• 财政年份: 2014
• 资助国家: 美国
• 起止时间: 2014-01-01 至 2017-12-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8633738
• 关键词: Acute; Adult; Allan-Herndon-Dudley syndrome; Apoptosis; Area; Binding; Biological Preservation; Brain; Brain Diseases; Brain Injuries; Brain region; Calmodulin; Candidate Disease Gene; Cell Line; Cell model; ChIP-seq; Chickens; Chronic; Development; Differentiation and Growth; ES Cell Line; Elderly; Embryo; Enzymes; Gene Activation; Gene Expression; Gene Expression Profile; Gene Expression Regulation; Gene Mutation; Gene Targeting; Genes; Genetic; Goals; Grant; Human; Hypothyroidism; Hypoxia; In Vitro; Individual; Injury; Iodide Peroxidase; Lead; Ligands; Link; MAP Kinase Gene; MEKs; Mediating; Messenger RNA; Metabolic Pathway; Modeling; Modification; Mood Disorders; Mus; Neurologic Deficit; Neuronal Differentiation; Neurons; Nuclear; Ovalbumin; Pathway interactions; Pattern; Phosphotransferases; Process; Profound Mental Retardation; Protein Isoforms; Recovery; Refractory; Regulation; Reporting; Rodent; Rodent Model; Role; Sampling; Serum; Signal Transduction Pathway; Signaling Pathway Gene; Specimen; System; Techniques; Testing; Thyroid Gland; Thyroid Hormone Receptor; Thyroid Hormones; Thyroxine; Traumatic Brain Injury; Tretinoin; Triiodothyronine; Veterans; Woman; base; chromatin immunoprecipitation; cognitive function; embryonic stem cell; genome-wide; hippocampal pyramidal neuron; hormone analog; improved; in vitro Model; in vivo; inhibitor/antagonist; nerve injury; nerve stem cell; neural growth; neurodevelopment; neuron loss; neuronal growth; neuronal patterning; neuronal survival; novel; public health relevance; receptor binding; relating to nervous system; response; response to injury; stem; therapeutic target; tool; transcription factor; transcription factor USF; transport inhibitor; uptake

Triiodothyronine (T3) and retinoic acid (RA) are essential for normal neuronal differentiation and growth. We have utilized neuronal cell lines, and embryonic stem (ES) cells differentiated into neurons, to identify T3 and RA gene targets. Thyroid hormone receptor (TR) ¿ is the predominant isoform expressed in neurons and has features distinct from those of TR¿. In the previous grant period we identified a link between RA and T3 in neural development. RA stimulates expression of the Monocarboxylate Transporter 8 (Mct8) thyroid hormone transporter, which in turn promotes neuronal T3 uptake. Profound mental retardation and neurologic deficits are reported in humans with gene mutations that inactivate Mct8, Allan-Herndon-Dudley Syndrome, and these individuals are refractory to treatment with T3. Traumatic Brain Injury (TBI) models show reduced levels of T3 in the serum and brain. This project will focus on the role of T3 and RA in promoting neural growth and differentiation as well as recovery from injury. We will identify the mechanisms of T3 and RA gene regulation and modulation of signal transduction pathways. We will determine the functional role of thyroid transporters, especially MCT8 and MCT10, and their influence on neuronal growth, differentiation, and neuron-specific gene expression. We have developed a technique to differentiate mouse ES cells into pyramidal neurons, a unique model to study T3 action in the brain. We will also study gene expression in specific brain areas of specimens from rodent models of acute and chronic TBI. We will use thyroid transport inhibitors and transporter mRNA knockdowns to determine the functional importance of T3 transport. The thyroid hormone analog, DITPA, does not require the Mct8 neural transporter to enter neurons and will be a complimentary tool to probe the importance of the thyroid transport. We will use inhibitors and knockdowns of pathway components to determine the role of the Wnt/¿ catenin and MEK/ERK MAPK pathways in regulation of neuronal proliferation and thyroid hormone transport. We will utilize genetic approaches to determine the role of TR¿ and TR¿ on T3-mediated genes to promote neural differentiation, growth and to prolong neuronal survival. We will evaluate known T3-regulated genes in pyramidal neurons important for growth and differentiation, as well as performing a genome-wide ChIP-Seq project, based on TR¿ binding, to identify new T3-regulated genes. We will determine the role of factors that modulate T3-regulation of neuronal growth and differentiation, including the actions of Chicken Ovalbumin Upstream Transcription Factor (COUP-TF1) and Calmodulin-Dependent Kinase IV (CamKIV). Finally, we will test expression of T3 signaling pathway genes in rodent brain areas after an acute and chronic TBI model. Our hypothesis is that specific actions of RA on signal transduction pathways and T3 on nuclear gene expression promote neuronal differentiation and growth and prolong neuronal survival, and the response to injury may recapitulate the developmental patterns of neuronal growth and differentiation. Our goal is to identify therapeutic targets with the potential to promote neural differentiation and growth in conditions such as TBI.

三碘甲状腺原氨酸 (T3) 和视黄酸 (RA) 对于正常神经元分化和 我们利用神经细胞系和分化成的胚胎干（ES）细胞。 神经元，识别 T3 和 RA 基因靶标。是占主导地位的 同种型在神经元中表达，具有与 TR 不同的特征.在之前的资助中 在此期间，我们发现了 RA 和 T3 在神经发育中的联系。 单羧酸转运蛋白 8 (Mct8) 甲状腺激素转运蛋白，进而促进 据报道，患有这种疾病的人类存在严重的精神发育迟滞和神经功能缺陷。 使 Mct8 失活的基因突变，Allan-Herndon-Dudley 综合征，这些个体是 对 T3 治疗无效的创伤性脑损伤 (TBI) 模型显示 T3 水平降低。 该项目将重点关注 T3 和 RA 在促进神经生长和大脑中的作用。 我们将确定 T3 和 RA 基因的分化和恢复机制。 我们将确定信号转导途径的功能作用。 甲状腺转运蛋白，特别是 MCT8 和 MCT10，及其对神经元生长的影响， 我们开发了一种分化技术。 小鼠 ES 细胞转化为锥体神经元，这是研究大脑中 T3 作用的独特模型。 研究急性和慢性啮齿动物模型标本特定脑区的基因表达 我们将使用甲状腺转运抑制剂和转运蛋白 mRNA 敲低来确定 TBI。 T3 转运的功能重要性。甲状腺激素类似物 DITPA 不需要 Mct8。 神经转运蛋白进入神经元，并将成为探索神经转运蛋白重要性的补充工具 我们将使用抑制剂和途径成分的敲除来确定甲状腺转运。 Wnt/¿ 的作用连环蛋白和 MEK/ERK MAPK 通路在神经元增殖和调节中的作用 我们将利用遗传方法来确定 TR 的作用。和 TR? T3介导的基因促进神经分化、生长并延长神经元存活。 我们将评估锥体神经元中已知的 T3 调节基因，这些基因对生长和发育很重要 分化，以及基于 TR¿ 进行全基因组 ChIP-Seq 项目绑定，至 确定新的 T3 调节基因。我们将确定调节 T3 调节的因素的作用。 神经元生长和分化，包括上游鸡卵清蛋白的作用 最后，我们将转录因子 (COUP-TF1) 和钙调蛋白依赖性激酶 IV (CamKIV)。 测试啮齿动物急慢性TBI后脑区T3信号通路基因的表达 我们的假设是 RA 对信号转导途径的特定作用和 T3 对信号转导途径的特定作用。 核基因表达促进神经元分化和生长并延长神经元存活， 对损伤的反应可能概括了神经生长和发育的发育模式 我们的目标是确定具有促进神经功能潜力的治疗靶点。 TBI 等条件下的分化和生长。