Gene-environment interactions in epithelial morphogenesis

上皮形态发生中的基因-环境相互作用

• 批准号: 10619541
• 负责人: YING XIA
• 金额: $ 45.49万
• 依托单位: UNIVERSITY OF CINCINNATI
• 依托单位国家: 美国
• 财政年份: 2019
• 资助国家: 美国
• 起止时间: 2019-04-09 至 2025-03-31
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10619541
• 关键词: Actins; Adverse effects; Affect; Animal Model; Aryl Hydrocarbon Receptor; Attenuated; Basic Science; Biological; Biological Process; Birth; CRISPR/Cas technology; Cell Separation; Cells; Chemicals; Complex; Congenital Abnormality; Defect; Development; Developmental Process; Dioxins; Disease; Embryo; Embryonic Development; Environment; Environmental Impact; Environmental Pollutants; Environmental Risk Factor; Epidermal Growth Factor Receptor; Epithelial Cells; Epithelium; Etiology; Event; Experimental Models; Exposure to; Eye; Eye diseases; Eyelid structure; Failure; Fetus; Funding; Gene Mutation; Genes; Genetic; Genetic Diseases; Genetic Predisposition to Disease; Genetic Risk; Goals; Grant; Health; Health Benefit; Heterozygote; Human; Impairment; In Vitro; Individual; Libraries; Link; MAP Kinase Gene; MAP3K1 gene; MAPK8 gene; Mammals; Mediating; Mediator; Modeling; Molecular; Morphogenesis; Movement; Mus; Mutant Strains Mice; Mutation; National Institute of Environmental Health Sciences; Newborn Infant; Pathway interactions; Patients; Phenotype; Play; Predisposition; Preventive measure; Public Health; Receptor Activation; Receptor Signaling; Regulation; Repression; Risk; Risk Assessment; Role; Signal Pathway; Signal Transduction; Spottings; Stimulus; Structural Congenital Anomalies; Structural defect; System; Testing; Tissues; Toxic effect; Translating; Translational Research; Work; adverse outcome; cell motility; complement system; disease phenotype; disorder risk; environmental chemical; environmental stressor; follow-up; functional outcomes; gene environment interaction; gene function; genetic approach; genetic makeup; global environment; human disease; in utero; in vivo; individualized prevention; induced pluripotent stem cell; insight; men; mouse model; mutant; novel; overexpression; personalized intervention; programs; response; small hairpin RNA; tool; translational approach; upstream kinase

Project Summary/Abstract The dioxin-like chemicals (DLCs) are global environmental pollutants that pose a significant health threat to humans. It is widely believed that the genetic make-up is a major determinant of disease risk from exposure, but the actual gene-environment mechanisms that predispose individuals to disease are poorly understood. We have developed a mouse model to investigate gene mutations that sensitize developmental tissues to dioxin toxicity. The model is based on embryonic eyelid closure, a developmental process conserved in all mammals. Eyelid closure is a major morphogenetic event occurring in late embryogenesis, driven by forward movement of the eyelid epithelial cells leading to fusion of the opposing eyelids. Failure of eyelid closure is not life threatening but results in an eye open at birth (EOB) phenotype in the newborns. The EOB phenotype is easy to spot, and consequently is found in a large number of genetic mutant strains. Over the years, the EOB mice serve as a powerful tool to elucidate the genetic network and signaling mechanisms underlying epithelium morphogenesis. Building on this model, we have identified the MAP3K1-JNK signaling cascades in the regulation of eyelid closure. We recently applied this system to investigate the genetic susceptibility to environmental chemical toxicity, and showed that the combination of Map3k1 gene heterozygosity and in utero dioxin exposure blocks eyelid closure whereas neither condition alone has a detrimental effect. These observations suggest that eyelid closure defect can be a multifactorial disorder resulting from gene-environment (GxE) interactions. The current proposal will investigate in three Specific Aims the mechanisms of GxE interactions by testing the hypothesis that genetic and environmental stresses converge on repression of the MAP3K1-JNK pathway to disrupt epithelial morphogenesis. Aim 1 will determine the molecular link between the dioxin signals and the MAP3K1- JNK pathways. Guided by preliminary findings, we will test whether the EGFR pathway mediates the crosstalk between these signals in eyelid development. Results will define a novel mechanism where the genetic and environmental factors target separate signaling pathways, but the crosstalk of the pathways leads to adverse outcomes. Aim 2 will identify novel genetic components of the MAP3K1 pathway in dioxin toxicity. Results will lead to a mechanistic understanding of the genetic conditions susceptible to chemical toxicity. Aim 3 will bridge the gap between basic and translational research by taking advantage of the identification of MAP3K1 heterozygosity in a patient with congenital eye structural abnormalities. We will use patient-specific induced pluripotent stem cells (iPSCs) to examine whether dioxin treatment during in vitro differentiation leads to inactivation of MAP3K1 signaling and impaired epithelial cell migration, which are biological endpoints linked to defective eyelid closure. Results will bring us a step closer to translate mechanistic discoveries in mice to understanding human diseases. Studies proposed in this project will provide critical insights into the mechanisms of GxE interactions and an experimental paradigm to study multifactorial etiology underlying birth defects.

项目概要/摘要 二恶英类化学物质 (DLC) 是全球环境污染物，对人类健康构成重大威胁 人类。人们普遍认为，基因组成是暴露引起的疾病风险的主要决定因素，但是 人们对导致个体患病的实际基因-环境机制知之甚少。我们 开发了一种小鼠模型来研究使发育组织对二恶英敏感的基因突变 毒性。该模型基于胚胎眼睑闭合，这是所有哺乳动物中保守的发育过程。 眼睑闭合是胚胎发生晚期发生的主要形态发生事件，由眼睑向前运动驱动 眼睑上皮细胞导致对侧眼睑融合。眼睑闭合失败不会危及生命 但会导致新生儿出生时睁眼（EOB）表型。 EOB 表型很容易发现，并且 因此，在大量的基因突变株中发现了这种现象。多年来，EOB 小鼠作为 阐明上皮形态发生背后的遗传网络和信号机制的有力工具。 在此模型的基础上，我们确定了 MAP3K1-JNK 信号级联在眼睑调节中的作用。 关闭。我们最近应用该系统来研究对环境化学物质的遗传易感性 毒性，并表明 Map3k1 基因杂合性和子宫内二恶英暴露的组合会阻止 眼睑闭合，而单独使用这两种情况都不会产生有害影响。这些观察表明眼睑 闭合缺陷可能是由基因-环境 (GxE) 相互作用引起的多因素疾病。目前的 提案将通过测试假设来研究 GxE 相互作用的三个具体目标的机制 遗传和环境压力集中在对 MAP3K1-JNK 通路的抑制上，从而破坏 上皮形态发生。目标 1 将确定二恶英信号与 MAP3K1- 之间的分子联系 JNK 途径。根据初步结果，我们将测试EGFR通路是否介导串扰 眼睑发育过程中这些信号之间的关系。结果将定义一种新的机制，其中遗传和 环境因素针对不同的信号通路，但通路的串扰会导致不利的结果 结果。目标 2 将鉴定二恶英毒性中 MAP3K1 途径的新遗传成分。结果将 导致对易受化学毒性影响的遗传条件的机械理解。目标 3 将桥接 利用 MAP3K1 的鉴定来缩小基础研究和转化研究之间的差距 先天性眼睛结构异常患者的杂合性。我们将使用患者特异性诱导 多能干细胞 (iPSC) 用于检查体外分化过程中二恶英处理是否会导致 MAP3K1 信号失活和上皮细胞迁移受损，这是与 眼睑闭合不良。结果将使我们更接近将小鼠的机制发现转化为 了解人类疾病。该项目提出的研究将为该机制提供重要的见解 GxE 相互作用和研究出生缺陷的多因素病因学的实验范式。