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.

三碘甲醇（T3）和视黄酸（RA）对于正常神经元分化和 生长。我们利用了神经元细胞系和胚胎茎（ES）细胞分化为 神经元，以识别T3和RA基因靶标。甲状腺马酮受体（TR）是主要的 同工型在神经元中表达，其特征与Tr的特征不同。在上一个赠款中 我们确定了RA和T3之间在神经发育中的联系。 RA刺激表达 单羧酸盐转运蛋白8（MCT8）甲状腺骑马转运蛋白转运蛋白，进而促进 神经元T3摄取。人类有严重的智力低下和神经系统缺陷 失活MCT8，Allan-Herndon-Dudley综合征的基因突变，这些人是 对用T3治疗的难治性。创伤性脑损伤（TBI）模型显示T3水平降低 血清和大脑。该项目将侧重于T3和RA在促进神经元增长和 分化以及从伤害中恢复。我们将确定T3和RA基因的机制 信号转导途径的调节和调制。我们将确定 甲状腺转运蛋白，尤其是MCT8和MCT10及其对神经元生长的影响， 分化和神经特异性基因表达。我们已经开发了一种技术来区分 小鼠ES细胞进入锥体神经元，这是研究大脑中T3作用的独特模型。我们也会 从急性和慢性的啮齿动物模型的样品的特定大脑区域中研究基因表达 TBI。我们将使用甲状腺转运抑制剂和转运蛋白mRNA敲低来确定 T3运输的功能重要性。甲状腺激素类似物DITPA不需要MCT8 神经转运蛋白进入神经元，将成为探测重要性的免费工具 甲状腺运输。我们将使用抑制剂和途径组件的敲低来确定 Wnt/¿catenin和Mek/Erk MAPK途径在神经元增殖和 甲状腺马内运输。我们将利用遗传方法来确定TRT的作用和 在T3介导的基因上促进神经元分化，生长和延长神经元存活。 我们将评估在锥体神经元中对生长和生长和 分化以及基于tr的结合，进行全基因组芯片序列项目 识别新的T3调节基因。我们将确定调节T3调节的因素的作用 神经元的生长和分化，包括上游鸡肉卵巢的作用 转录因子（COUP-TF1）和钙调蛋白依赖性激酶IV（CAMKIV）。最后，我们会的 急性和慢性TBI后，啮齿动物脑区域中T3信号通路基因的测试表达 模型。我们的假设是RA对信号传输途径的特定作用和T3对 核基因表达促进神经元分化和生长以及延长神经元存活， 对伤害的反应可能会概括神经元生长的发育模式和 分化。我们的目标是确定具有促进神经元的潜力的治疗靶标 TBI等条件下的分化和增长。