Genetic, Tissue, and Anatomical Interactions in Mandibulofacial Dysmorphogenesis

项目摘要 面部异常总是需要某种类型的治疗、矫正手术和密切的随访， 给病人及其家属带来经济和精神负担。尽管对人类数据的分析 是至关重要的，人类研究提出了特殊的问题，其中最重要的是产前的关键时期， 发展不可用于研究。该建议旨在确定发育和分子 利用我们通过系统识别的小鼠突变体， 搜索国际小鼠表型鉴定协会（IMPC）的当前内容， NIH PAR-20-137用于IMPC胚胎和围产期致死KO小鼠系的表型分型。微米或 下颌后缩是用于描述下颌面骨发育不全中下颌表型的最常用术语， 然而，目前缺乏精确的诊断下颌骨畸形没有严格考虑， 这些疾病的潜在不同病因及其对异常潜在后遗症的影响。 小颌畸形描述了一个下颌骨是绝对减少的大小，表明下颌骨主要是 下颌后缩是指正常大小的下颌骨相对于上颌骨位于后方 下巴.因此，小颌畸形和缩颌畸形虽然提供相似的面部轮廓，但由不同的原发性 发育过程，每一个可能与舌和腭发育不同的整合。当 下颌骨畸形会出现舌下垂、呼吸道阻塞，在某些情况下，会出现腭裂， 该病症被称为皮埃尔·罗宾（PR）。一系列发育性脑血管病的致病机理 事件已被假设为PR，但很少有明确的因果关系之间发现的突变， 基因表达失调、精确的细胞过程和PR相关的异常都有记录。到 为了验证这一假设，我们计划对IMPC突变小鼠进行一系列仔细协调和充分合作的分析 基于已知导致人类PR的基因或基于PR特征的存在而鉴定的品系 记录在这些老鼠线上。我们深入的表型分析将涉及：目标1：定量3D形态学 用磷钨酸增强的显微计算机断层扫描分析胚胎; Aim 2：差异 突变体和未受影响的相关组织和发育时间点的基因表达分析 使用批量RNA-seq和空间转录组学的同窝对照;目的3：使用原位 相关基因、信号通路、细胞过程的杂交或免疫组织化学， 分化状态，以确定细胞和分子事件引起的畸形的 下颌面复合体这种多层次的系统生物学方法将为生物学提供精确的定义。 遗传变异对下颌骨及相关舌、腭和上呼吸道表型的局部影响 以确定其生产中涉及的发育和分子功能，使用小鼠品系， 与这些病症相关的表型。

PROJECT SUMMARY Anomalies of the face invariably require some type of therapy, corrective surgery, and close follow-up while imposing a financial and emotional burden on patients and their families. Although the analysis of human data is critical, human studies pose particular problems, not the least of which is that critical times of prenatal development are not available for study. This proposal aims to identify the developmental and molecular processes underlying mandibulofacial anomalies using mouse mutants that we identified by systematically searching the current contents of the International Mouse Phenotyping Consortium (IMPC) in response to NIH PAR-20-137 for phenotyping IMPC embryonic and perinatal lethal KO mouse lines. Micro- or retrognathia are the most common terms used to describe mandibular phenotypes in mandibulofacial dysostosis, yet the current lack of precision in diagnoses of mandibular dysmorphology does not critically consider the potentially distinct etiology of these conditions and their influence on potential sequelae of anomalies. Micrognathia describes a mandible that is absolutely reduced in size, indicating that the mandible is primarily affected, while retrognathia refers to a normally sized mandible that is placed posteriorly relative to the upper jaw. Thus, micrognathia and retrognathia, while providing similar facial profiles, are produced by different primary developmental processes and each may integrate differently with tongue and palatal development. When mandibular dysmorphology occurs with glossoptosis, respiratory obstruction, and in some cases, a cleft palate, the condition is referred to as Pierre Robin (PR). A causative pathogenesis of a sequence of developmental events has been hypothesized for PR, but few clear causal relationships between discovered mutations, dysregulated gene expression, precise cellular processes, and PR-associated anomalies are documented. To test this hypothesis, we plan a carefully coordinated and fully collaborative set of analyses of IMPC mutant mouse lines identified based on genes known to be causative for PR in humans or on the presence of PR features recorded in these mouse lines. Our in-depth phenotyping will involve: Aim 1: quantitative 3D morphologic analyses of embryos using phosphotungstic acid-enhanced micro computed tomography; Aim2: differential gene expression analysis of relevant tissues and developmental time points between mutant and unaffected littermate controls using bulk RNA-seq and spatial transcriptomics; Aim 3: histologic studies using in situ hybridization or immunohistochemistry of relevant genes, signaling pathways, cellular processes, and differentiation states to determine the cellular and molecular events giving rise to dysmorphogenesis of the mandibulofacial complex. This multi-level, systems biology approach will provide precise definitions of the localized effects of genetic variants on mandibular and associated tongue, palatal, and upper airway phenotypes to identify the developmental and molecular functions involved in their production, using mouse lines that model the phenotypes associated with these conditions.