Cellular and Molecular Analysis of the Role of Inositol in Neurulation

肌醇在神经形成中作用的细胞和分子分析

• 批准号: 8835126
• 负责人: Rachel Melissa Brewster
• 金额: $ 7.34万
• 依托单位: UNIVERSITY OF MARYLAND BALTIMORE COUNTY
• 依托单位国家: 美国
• 财政年份: 2014
• 资助国家: 美国
• 起止时间: 2014-04-08 至 2016-03-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8835126
• 关键词: A Mouse; Address; Area; Biological Models; Brain; Centrosome; Clinical Trials; Congenital Abnormality; Defect; Dorsal; Embryo; Exhibits; Failure; Floor; Folic Acid; Frequencies; Genetic; Goals; Health; Human; Image; Inositol; Inositol Metabolism Pathway; Life; Mediating; Methods; Microtubule-Organizing Center; Microtubules; Modeling; Molecular Analysis; Neural Tube Defects; Neural tube; Organelles; Pathway interactions; Phenotype; Phosphotransferases; Phytic Acid; Prevention; Process; Proteins; Research; Resistance; Role; Sagittaria; Shapes; Spinal; Staging; Supplementation; System; Testing; Vertebrate Biology; Width; Work; Zebrafish; base; cell behavior; cell motility; design; dietary supplements; knock-down; loss of function; mutant; neural plate; novel; planar cell polarity; polarized cell; prevent; protective effect; relating to nervous system; retinal rods; tool

DESCRIPTION (provided by applicant): Neural tube defects (NTDs) are among the most frequent birth defects in humans, with a frequency of 1/1000 for spinal bifida alone. Given the high frequency of NTDs, an important area of research focus has been on preventative methods. In many cases NTDs can be prevented by maternal supplementation with folic acid. Nevertheless, around 30% of NTDs are unresponsive to this dietary supplement and there is currently no therapy available for these defects. Increasing evidence suggests that inositol supplementation can help prevent folate-resistant NTDs and a clinical trial is currently underway to test this possibility. Our long-term objective is to understand how inositol exerts its protectve effect during neurulation. The goal of this proposal is to investigate a putative mechanism by which inositol metabolism promotes neural convergence extension (CE), an early and essential stage of neurulation, using zebrafish as a model system. We will address the general hypothesis that Inositol 1,3,4,5,6-pentakisphosphate 2-kinase (Ipk1), the kinase that generates inositol hexakisphosphate (IP6), interacts with the ciliary protein Ift88 to mediate the polarized cell movements that drive neural CE. In Aim 1 we will investigate the mechanism by which Ift88 functions in neural CE. Our working hypothesis is that Ift88 nucleates cytoplasmic microtubules (MTs), which we know to be required for polarized cell movement. This hypothesis will be tested by examining the integrity of the MT network in Ift88-depleted embryos. In Aim 2 we will determine if Ipk1 promotes neural CE by regulating MTs in an Ift88-dependent manner. This research goal will be achieved by comparing the phenotypes observed in Ipk1, Ift88 and Ipk1; Ift88 double mutants and testing the requirement for Ipk1 in the centrosome, the organelle that nucleates MTs. The proposed work should increase our understanding of the function of Ift88 and Ipk1, reveal essential mechanisms underlying neural tube formation and provide the basis for a model on the protective effect of inositol.

描述（由申请人提供）：神经管缺陷 (NTD) 是人类最常见的出生缺陷之一，仅脊柱裂的发生频率就是 1/1000。鉴于 NTD 的高发生率，一个重要的研究重点领域是预防方法。在许多情况下，母亲补充叶酸可以预防 NTD。然而，大约 30% 的 NTD 对这种膳食补充剂没有反应，目前还没有针对这些缺陷的治疗方法。越来越多的证据表明，补充肌醇有助于预防叶酸耐药性 NTD，目前正在进行一项临床试验来测试这种可能性。 我们的长期目标是了解肌醇如何在神经形成过程中发挥其保护作用。该提案的目标是使用斑马鱼作为模型系统，研究肌醇代谢促进神经收敛延伸（CE）的假定机制，这是神经形成的早期和重要阶段。我们将讨论一般假设，即肌醇 1,3,4,5,6-五磷酸 2-激酶 (Ipk1)（生成肌醇六磷酸 (IP6) 的激酶）与纤毛蛋白 Ift88 相互作用，介导驱动极化细胞运动神经CE。在目标 1 中，我们将研究 Ift88 在神经 CE 中发挥作用的机制。我们的工作假设是 Ift88 使细胞质微管 (MT) 成核，我们知道这是极化细胞运动所必需的。这一假设将通过检查 Ift88 耗尽胚胎中 MT 网络的完整性来检验。在目标 2 中，我们将确定 Ipk1 是否通过以 Ift88 依赖性方式调节 MT 来促进神经 CE。该研究目标将通过比较 Ipk1、Ift88 和 Ipk1 中观察到的表型来实现； Ift88 双突变体并测试中心体（使 MT 成核的细胞器）对 Ipk1 的需求。拟议的工作应该增加我们对 Ift88 和 Ipk1 功能的理解，揭示神经管形成的基本机制，并为肌醇的保护作用模型提供基础。