Role of Cytoskeletal Protein SPECC1L in Facial Morphogenesis and Facial Clefting

细胞骨架蛋白 SPECC1L 在面部形态发生和面部裂隙中的作用

• 批准号: 8480396
• 负责人: Irfan Saadi
• 金额: $ 22.65万
• 依托单位: UNIVERSITY OF KANSAS MEDICAL CENTER
• 依托单位国家: 美国
• 资助国家: 美国
• 起止时间: 至
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/8480396
• 关键词: Actins; Affect; Alleles; Antibodies; Biological Assay; Branchial arch structure; Cell Line; Cell-Cell Adhesion; Cells; Cellular Morphology; Cephalic; Cleaved cell; Cleft lip with or without cleft palate; Collaborations; Complement; Congenital Abnormality; Cytoskeletal Proteins; Cytoskeleton; Data; Defect; Development; Drosophila genus; ES Cell Line; Employee Strikes; Endothelin; Exhibits; Eye; Face; Focal Adhesions; Galactosidase; Genes; Genomics; German population; Homologous Gene; Human; Image; Instruction; Integrin Signaling Pathway; Integrins; Kinetics; Label; Life; Live Birth; Medical; Microtubules; Modeling; Molecular; Morphogenesis; Mus; Mutate; Mutation; Neural Crest; Neural Crest Cell; Nuclear; Oral cavity; Orthologous Gene; Pathway interactions; Patients; Persons; Phenocopy; Primordium; Productivity; Proteomics; Publications; Regulation; Reporter; Reporter Genes; Role; Screening procedure; Services; Signal Pathway; Signal Transduction; Speed; Staging; Structure; Testing; Tissues; Transgenic Organisms; Tubulin; Tungsten; Vertebrates; Zebrafish; base; cDNA Arrays; cell motility; cellular imaging; crosslink; depolymerization; fly; insight; knock-down; life time cost; link protein; migration; mouse model; mutant; novel; orofacial; polymerization; protein protein interaction; vector

PROJECT SUMMARY (See instructions): Orofacial clefts are one of the most common birth defects in the U.S., occurring in 1/750 live births. The lifetime cost for medical treatment, educational services and lost productivity averages more than $100,000 per affected person. While the majority of orofacial clefts result in cleft lip with or without cleft palate (CL/P), a small percentage results in oblique facial clefts (ObFC) that extend from the oral cavity to the eye. Although less common, insights into the cellular mechanism of ObFC - first definitively classified by Paul Tessier in 1976 - have remained elusive. We have identified two de novo occurrences of SPECC1L mutations in patients with ObFC. Our studies in zebrafish and fly provide significant insight into SPECC1L function, which thus far had remained unstudied with no scientific publications. Knockdown of a previously uncharacterized zebrafish SPECC1L homolog perturbs cranial neural crest (CNC) and results in a dramafic loss of facial structures, thus extending SPECC1L function in facial morphogenesis to other vertebrates. In addition, knockdown of the sole uncharacterized Drosophila ortholog phenocopies - to an extraordinary extent - known fly mutants in the integrin-signaling pathway that exhibit cell adhesion and migration defects. Furthermore, our cellular and molecular analyses show that SPECC1L is a novel cytoskeletal cross-linking protein that interacts with both the microtubule and actin cytoskeletons. Transient expression of SPECC1LGFP stabilizes a subset of microtubules, while SPECC1L knockdown causes defective actin cytoskeleton reorganization and impairs cell adhesion and migration. Together with mouse Speed I expression in the developing facial prominences, these results begin to explain how human ObFC can arise following SPECC1L deficiency. The aim of this proposal is to develop a mouse model to test the pathogenetic mechanism of SPECC1L deficiency in mammalian facial morphogenesis (Aim 1) and to precisely define the cellular (Aim 2) and molecular (Aim 3) role of SPECC1L in CNC cell migration and specification of facial structures.

项目摘要（参见说明）： 口面部裂是美国最常见的出生缺陷之一，发生在 1/750 的活产儿中。每个受影响者的终生医疗、教育服务和生产力损失平均超过 100,000 美元。虽然大多数口颌裂会导致伴有或不伴有腭裂的唇裂 (CL/P)，但一小部分会导致从口腔延伸到眼睛的斜面裂 (ObFC)。 尽管不太常见，但对 ObFC 细胞机制的深入了解（由 Paul Tessier 于 1976 年首次明确分类）仍然难以捉摸。我们在 ObFC 患者中发现了两起 SPECC1L 突变。我们对斑马鱼和果蝇的研究提供了对 SPECC1L 功能的重要见解，但迄今为止尚未对其进行研究，也没有任何科学出版物。先前未表征的斑马鱼 SPECC1L 同源物的敲除扰乱了颅神经嵴 (CNC) 并导致了戏剧性的结果 面部结构的丧失，从而将 SPECC1L 在面部形态发生中的功能扩展到其他脊椎动物。此外，在整合素信号通路中，唯一未表征的果蝇直系同源表型的敲低在很大程度上是已知的果蝇突变体，这些突变体表现出细胞粘附和迁移缺陷。 此外，我们的细胞和分子分析表明，SPECC1L 是一种新型细胞骨架交联蛋白，可与微管和肌动蛋白细胞骨架相互作用。 SPECC1LGFP 的瞬时表达可稳定一部分微管，而 SPECC1L 敲低会导致有缺陷的肌动蛋白细胞骨架重组，并损害细胞粘附和迁移。结合小鼠 Speed I 在发育中的面部突出中的表达，这些结果开始解释人类 ObFC 如何在 SPECC1L 缺陷后出现。本提案的目的是开发一种小鼠模型来测试 SPECC1L 缺陷在哺乳动物面部形态发生中的发病机制（目标 1），并精确定义 SPECC1L 在 CNC 细胞迁移和面部结构规范中的细胞（目标 2）和分子（目标 3）作用。