The cadherin Desmoglein-2 controls cell spreading and extracellular matrix gene expression.

钙粘蛋白 Desmoglein-2 控制细胞扩散和细胞外基质基因表达。

• 批准号: 10653447
• 负责人: Adi D Dubash
• 金额: $ 36.47万
• 依托单位: FURMAN UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2023
• 资助国家: 美国
• 起止时间: 2023-04-01 至 2026-03-31
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10653447
• 关键词: Adhesives; Apoptosis; Behavior; Binding; Biological; Biological Process; Cadherins; Cell membrane; Cell physiology; Cell-Cell Adhesion; Cell-Matrix Junction; Cells; Collagen; Complex; Cytoskeletal Filaments; Data; Desmosomes; Epithelium; Extracellular Domain; Extracellular Matrix; Extracellular Matrix Proteins; Extracellular Space; Fibronectins; Fostering; Foundational Skills; Gene Expression; Gene Structure; Guanosine Triphosphate Phosphohydrolases; Institution; Intermediate Filaments; Knock-out; Link; Maintenance; Mechanical Stress; Mediating; Membrane; Methods; Modeling; Molecular; Morphogenesis; NF-kappa B; Pathway interactions; Play; Process; Proliferating; Proteins; Regulation; Role; Science; Signal Transduction; Structure; Tail; Testing; Tissues; Training; Universities; Work; career; cell motility; desmocollin; desmoglein; desmoglein 2; desmoplakin; experimental study; extracellular; insight; knock-down; migration; novel; organizational structure; plakoglobin; plakophilins; protein complex; response; tissue repair; undergraduate student; wound healing

PROJECT SUMMARY The desmosome cell-cell adhesion complex plays an important role in the maintenance of tissue structure and integrity in response to mechanical stress. In addition to this central adhesive role, desmosomal proteins also coordinate multiple processes such as proliferation, apoptosis, differentiation and cell migration. Prior studies show that desmosomal cadherins, the proteins responsible for mediating the extracellular attachment between cells, can have both pro- and anti-migratory functions, indicating that their influence on migration is more complex than a simple consequence of defective cell-cell attachment. Our recent work has shown that loss of the cadherin Desmoglein-2 (DSG2) triggers increased activation of the Rap1 GTPase, leading to enhanced cell spreading on extracellular matrix (ECM) proteins (such as fibronectin and collagen). As these experiments were performed on singly spreading cells, we have identified a novel cell-autonomous, cell-cell adhesion independent role for DSG2 in the regulation of cell spreading. Nevertheless, the signaling mechanisms via which DSG2 regulates Rap1 activity remain unknown. Our preliminary data also shows that localization of the Rap1 activator PDZ-GEF2 is dramatically altered in DSG2 knockout cells, and that knockdown of the desmosomal protein Desmoplakin (DSP) can rescue both the enhanced spreading and mis-localization of PDZ-GEF2 seen in these cells. Further, we have obtained evidence that loss of DSG2 increases ECM gene expression via deregulated Src and NF-kB signaling. In this proposal, we will test the central hypothesis that DSG2 orchestrates cell-matrix adhesion and spreading through control of both inside-out signaling (via Rap1 GEFs) and outside-in signaling (via ECM gene expression). In Aim 1, we will investigate whether binding of PDZ-GEF2 to DSG2 or DSP reduces its activity, thereby inducing inside-out control of cell spreading via inhibition of Rap1 signaling. In Aim 2, we will explore a role for NF-kB and Src signaling in DSG2-dependent ECM gene expression, and whether this promotes outside-in control of cell-matrix spreading and migration. Finally, in Aim 3, we will explore the hypothesis that the ability of DSG2 to regulate cell migration is independent of its extracellular domains and/or localization to the cell membrane. The scientific impact of these data will be to produce a comprehensive picture of the molecular mechanisms by which the desmosomal cadherin DSG2 coordinates both inside-out and outside-in signaling to control cell-matrix adhesion, spreading and migration, functions critical for biological processes such as tissue morphogenesis, wound healing and re- epithelialization. The training impact of these data will be to provide undergraduate students at Furman University (a primarily undergraduate institution) with foundational skills in the scientific method, foster their desire to tackle important biological problems and pursue a career in the biomedical sciences.

项目摘要 脱骨小细胞 - 细胞粘附复合物在维持组织结构中起重要作用 和响应机械应力的完整性。除了这种中央粘合剂的作用外 蛋白质还协调多个过程，例如增殖，凋亡，分化和细胞 迁移。先前的研究表明，脱乳小蛋白是负责介导的蛋白 细胞之间的细胞外附着可以具有促和抗迁移功能，表明它们 对迁移的影响比有缺陷的细胞 - 细胞附着的简单结果更为复杂。我们的 最近的工作表明，钙粘蛋白脱莫格蛋白-2（DSG2）的损失触发了增加的激活 RAP1 GTPase，导致细胞扩散在细胞外基质（ECM）蛋白上（例如 纤连蛋白和胶原蛋白）。由于这些实验是在单个传播细胞上进行的，因此我们有 鉴定出一种新型的细胞自主，细胞 - 细胞粘附在细胞调节中的独立性独立性 蔓延。然而，DSG2调节RAP1活性的信号传导机制仍然存在 未知。我们的初步数据还表明，RAP1激活剂PDZ-GEF2的定位非常明显 DSG2基因敲除细胞的改变，脱骨蛋白脱莫普拉金（DSP）的敲除可以 挽救在这些细胞中看到的PDZ-GEF2的增强的扩散和错误定位。此外，我们 已经获得证据表明，DSG2的损失通过失调的SRC和NF-KB增加了ECM基因表达 信号。在此提案中，我们将测试DSG2策划细胞矩阵的中心假设 通过控制内而外信号（通过RAP1 GEF）和外部控制的粘附和扩散 信号传导（通过ECM基因表达）。在AIM 1中，我们将调查PDZ-GEF2的结合是否与 DSG2或DSP降低了其活性，从而通过抑制RAP1诱导了对细胞扩散的内而外的控制 信号。在AIM 2中，我们将探索NF-KB和SRC信号在DSG2依赖性ECM基因中的作用 表达以及这是否促进了外部控制细胞矩阵扩散和迁移。最后，在 AIM 3，我们将探讨以下假设：DSG2调节细胞迁移的能力与其独立 细胞外结构域和/或定位到细胞膜。这些数据的科学影响将是 为了产生分子机制的全面图片 DSG2均协调内而外和外部信号传导，以控制细胞矩阵粘附，扩散和 迁移，对生物学过程（例如组织形态发生，伤口愈合和重新）至关重要的作用 上皮化。这些数据的培训影响将是为Furman提供本科生 大学（主要是本科机构）具有科学方法的基础技能，培养他们的 渴望解决重要的生物学问题并从事生物医学科学的职业。