FGF Signaling Pathways and Craniofacial Development

FGF 信号通路与颅面发育

• 批准号: 8837606
• 负责人: Philippe M Soriano
• 金额: $ 64.18万
• 依托单位: ICAHN SCHOOL OF MEDICINE AT MOUNT SINAI
• 依托单位国家: 美国
• 财政年份: 2012
• 资助国家: 美国
• 起止时间: 2012-07-11 至 2016-04-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8837606
• 关键词: Alleles; Area; Auditory; Binding; Biochemical; Biology; Cephalic; Cleft Lip; Cleft Palate; Congenital Abnormality; Craniofacial Abnormalities; Defect; Development; Dimerization; Disease; Dorsal; Drug Targeting; Ectoderm; Epithelium; Face; Fibroblast Growth Factor; Fibroblast Growth Factor Receptors; Gene Targeting; Growth Factor; Human; Individual; Laboratories; Lead; Mesenchymal; Mesenchyme; Mus; Mutagenesis; Mutant Strains Mice; Mutation; Neural Crest; Neural Crest Cell; Organ; Palate; Pathway interactions; Phenotype; Play; Point Mutation; Population; Prevention; Process; Proteins; Role; Series; Signal Pathway; Signal Transduction; Tissues; base; bone; cell motility; cell type; craniofacial; craniofacial development; migration; mutant; neoplastic; novel; prevent; receptor; relating to nervous system; response; skeletal disorder

DESCRIPTION (provided by applicant): The major aims of this proposal are to identify signaling mechanisms initiated by FGFs that underlie normal development of the palate and the midface. Conditional deletion of the two receptors Fgfr1 and Fgfr2 lead to multiple craniofacial defects. Although FGF signaling has been extensively studied from a biochemical standpoint in many laboratories, including our own, remarkably little is known about how these signaling pathways regulate morphogenetic processes in craniofacial development. In this application, we propose: 1. To investigate the pathways regulated by FGF signaling in the palatal epithelium. Loss of Fgfr2 in the epithelium leads to a cleft palate. To establish the signaling mechanisms underlying this defect, we will generate and analyze an allelic series of conditional signaling mouse mutants at the Fgfr2 locus that prevent the binding of single or multiple effector proteins. We will further characterize transcriptional targets of Fgfr2 signaling in the palatal epithelium and determine if they can regulate subsequent proliferation of the underlying mesenchyme. 2. To investigate the pathways regulated by FGF signaling in the neural crest. Loss of Fgfr1 in the neural crest leads to multiple craniofacial defects, including in palate closure. To identify the underlying signaling mechanisms, we will generate and characterize an allelic series of conditional signaling mouse mutants at the Fgfr1 locus that prevent the binding of single or multiple effectors proteins, targeting the same pathways as for Fgfr2. Since the palate and other craniofacial organs are derived from neural crest cells migrated from dorsal neural ectoderm, we will also conduct Cre based lineage analysis to characterize defects in neural crest cell migration that underlie the mutant phenotypes. 3. To identify and characterize the FGF regulated pathways that control frontonasal development. Combined loss of both Fgfr1 and Fgfr2 in neural crest cells leads to facial clefting that extends through the midline. To establish the mechanistic basis for this phenotype, we will perform conditional mutagenesis in neural crest cells with compound Fgfr1 and Fgfr2 conditional mutants carrying point mutations for identical effectors, and compare these to the double null mutants. We will further establish the role of FGF signaling in midface development by conditional mutagenesis specifically in the frontonasal process. The proposed studies are anticipated to have a significant impact in craniofacial biology because they will establish the signaling mechanisms by which FGFs exert their action and open new directions for the prevention of craniofacial birth defects by the possible application of drug targets for critical FGF intracellular effectors.

描述（由申请人提供）：该提案的主要目的是确定 FGF 发起的信号机制，该机制是上颚和中面部正常发育的基础。有条件地删除 Fgfr1 和 Fgfr2 两个受体会导致多种颅面缺陷。尽管 FGF 信号传导已在许多实验室（包括我们自己的实验室）从生化角度进行了广泛研究，但人们对这些信号传导途径如何调节颅面发育中的形态发生过程知之甚少。在此应用中，我们建议： 1. 研究腭上皮中 FGF 信号传导调节的途径。上皮细胞中 Fgfr2 的缺失会导致腭裂。为了建立这一缺陷背后的信号传导机制，我们将在 Fgfr2 位点生成并分析一系列等位基因条件信号传导小鼠突变体，这些突变体可阻止单个或多个效应蛋白的结合。我们将进一步表征腭上皮中 Fgfr2 信号转导的转录靶标，并确定它们是否可以调节底层间质的后续增殖。 2. 探讨神经嵴中FGF信号调控的通路。神经嵴中 Fgfr1 的缺失会导致多种颅面缺陷，包括腭闭合缺陷。为了确定潜在的信号传导机制，我们将在 Fgfr1 位点生成并表征一系列等位基因条件信号传导小鼠突变体，这些突变体阻止单个或多个效应蛋白的结合，靶向与 Fgfr2 相同的途径。由于腭和其他颅面器官源自从背侧神经外胚层迁移的神经嵴细胞，我们还将进行基于 Cre 的谱系分析，以表征突变表型背后的神经嵴细胞迁移缺陷。 3. 识别和表征控制额鼻发育的 FGF 调节途径。神经嵴细胞中 Fgfr1 和 Fgfr2 的联合缺失会导致延伸至中线的面部裂痕。建立 为了了解这种表型的机制基础，我们将使用带有相同效应器点突变的复合 Fgfr1 和 Fgfr2 条件突变体在神经嵴细胞中进行条件诱变，并将其与双无效突变体进行比较。我们将通过条件诱变，特别是在额鼻过程中，进一步确定 FGF 信号在中面部发育中的作用。拟议的研究预计将对颅面生物学产生重大影响，因为它们将建立 FGF 发挥作用的信号机制，并通过可能应用关键 FGF 细胞内效应器的药物靶点，为预防颅面出生缺陷开辟新方向。