Imaging and mechanistic analyses of face-brain dysmorphology in a CLP model

唇腭裂是最常见的颅面出生缺陷， 发病率，并需要广泛的医疗干预。除了面部畸形和继发性 CLP的并发症、中枢神经系统（CNS）异常以及认知和行为缺陷是 已知共同发生。重要的是，CLP的病因学基础以及相关CNS的病因和程度 异常现象仍然知之甚少。这种知识差距最好通过基础研究来解决。 然而，重大研究进展受到两个主要限制的阻碍：缺乏合适的 动物模型，以及缺乏研究人员的专业知识，以整合传统上不同的概念， 实验方法。这一竞技场的一个重要进展是我们最近证明， 暴露于Hedgehog（Hh）信号传导拮抗剂环巴胺诱导小鼠CLP，模拟 临床表型采用该模型，本文提出的研究使用高分辨率磁 共振成像，以确定与CLP同时发生的CNS畸形，并确定是否有独特的 这些异常的模式可以通过特定的面部表型来预测（Aim 1）。机械分析将 测试环巴胺暴露通过干扰脑-面部异常诱导相关脑-面部异常的假设， 在发育中的前脑和面中部之间的感应信号（目标2）。Hh途径靶向基因， 介导这些畸形的初始发病机制将被识别和表征（目的3），提供 一组候选基因，其在颅面发育中的功能和临床CLP的病因学作用将被 在未来的研究中继续。累积起来，预计这些研究将确定特定的CNS异常 存在于CLP患者中，并提供基础的病因病理学特征， 未来的努力，以研究化学和遗传干扰的相互作用，以Hh信号通路， 临床人群中CLP的发生。为了增加候选人以前在毒理学方面的经验， 细胞信号传导，这些研究目标与胚胎学中的教学和实践培训成分相结合， 神经发育，临床和分子遗传学。本提案中概述的机会将 为候选人提供多学科的概念背景和实验工具集， 阐明了CLP的复杂发病机制。这些任务的圆满完成将是 在查佩尔山的北卡罗来纳州大学提供的特殊研究环境的促进下， 以及颅面/神经发育专家（Kathleen Sulik博士）的指导和合作， 小动物成像（Al约翰逊博士）、3D脸型分析（Peter哈蒙德博士）、颅面遗传学 (Dr.埃里克埃弗雷特）和临床遗传学（亚瑟艾尔斯沃思博士）。最终， 这些努力将为候选人在一个环境中追求学术生涯的目标奠定基础 该组织将临床和基础科学家结合起来，以促进口腔和颅面健康。

Clefts of the lip and palate (CLP) are the most commonly occurring craniofacial birth defect, cause significant morbidity, and require extensive medical intervention. In addition to the facial malformations and secondary complications of CLP, central nervous system (CNS) abnormalities, and cognitive and behavioral deficits are known to co-occur. Importantly, the etiological basis of CLP, as well as the cause and extent of associated CNS abnormalities remain poorly understood. This knowledge gap is best addressed through basic research. However, significant research progress has been hampered by two major limitations: a paucity of suitable animal models, and a lack of investigators with the expertise to integrate traditionally disparate conceptual and experimental approaches. An important advance in this arena has been our recent demonstration that in utero exposure to the Hedgehog (Hh) signaling antagonist, cyclopamine, induces CLP in the mouse, mimicking clinical phenotypes. Employing this model, the studies proposed herein use high-resolution magnetic resonance imaging to define CNS dysmorphology that co-occurs with CLP and to determine whether unique patterns of these abnormalities can be predicted by specific facial phenotypes (Aim 1). Mechanistic assays will test the hypothesis that cyclopamine exposure induces associated brain-face abnormalities by disrupting inductive signals between the developing forebrain and midface (Aim 2). The Hh pathway target genes which mediate the initial pathogenesis of these malformations will be identified and characterized (Aim 3), providing a set of candidate genes whose function in craniofacial development and etiological role clinical CLP will be pursued in future studies. Cumulatively, it is expected that these studies will define specific CNS abnormalities that are present in patients with CLP and provide foundational etiopathological characterization that will drive future efforts to examine the interaction of chemical and genetic perturbations to the Hh signaling pathway in the genesis of CLP in clinical populations. To augment the candidate's previous experience in toxicology and cell signaling, these research aims are coupled with didactic and hands-on training components in embryology, neurodevelopment, and clinical and molecular genetics. The opportunities outlined in this proposal will provide the candidate with a multidisciplinary conceptual background and experimental toolset ideal for elucidation of the complex etiopathology of CLP. The successful completion of these undertakings will be fostered by the exceptional research environment provided at the University of North Carolina at Chapel Hill, and mentorship by and collaboration with experts in craniofacial/neurodevelopment (Dr. Kathleen Sulik), small animal imaging (Dr. Al Johnson), 3D face-shape analysis (Dr. Peter Hammond), craniofacial genetics (Dr. Eric Everett), and clinical genetics (Dr. Arthur Aylsworth). Ultimately, the undertaking and completion of these endeavors will provide a foundation for the candidate's goal of pursuing an academic career in a setting which incorporates clinical and basic scientists to advance oral and craniofacial health.