Investigating mechanisms regulating cell adhesion during tissue remodeling

研究组织重塑过程中调节细胞粘附的机制

• 批准号: 10229401
• 负责人: Donald Nathaniel Clarke
• 金额: $ 6.86万
• 依托单位: MASSACHUSETTS INSTITUTE OF TECHNOLOGY
• 依托单位国家: 美国
• 财政年份: 2019
• 资助国家: 美国
• 起止时间: 2019-09-01 至 2022-08-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/10229401
• 关键词: Adherens Junction; Adhesions; Adult; Affect; Affinity; Animal Model; Apical; Automobile Driving; Behavior; Behavior monitoring; Biochemical; Biological; Cadherins; Cancer Biology; Cell Adhesion; Cell Adhesion Molecules; Cell-Cell Adhesion; Cells; Cellular biology; Cessation of life; Complex; Congenital Disorders; Data; Defect; Development; Disease; Dorsal; Drosophila genus; Drosophila melanogaster; E-Cadherin; Ectopic Expression; Embryo; Embryonic Development; Epithelial; Event; Failure; Fogs; Gene Silencing; Genes; Genetic; Genetic Transcription; Geometry; Germ Layers; Goals; Health; Homeostasis; Human; Image; Intercellular Junctions; Knowledge; Link; Malignant Neoplasms; Mass Screening; Mass Spectrum Analysis; Mesenchymal; Mission; Modeling; Morphogenesis; Nature; Neoplasm Metastasis; Outcome; Pathway interactions; Post-Transcriptional Regulation; Post-Translational Protein Processing; Process; Proteins; Proteomics; RNA Interference; Regulation; Repression; Research; Role; Signal Transduction; Snails; Subcellular structure; System; Testing; Tissues; Transcriptional Regulation; United States National Institutes of Health; Work; base; beta catenin; cancer cell; cell behavior; cell motility; comparative; constriction; embryo tissue; fly; gastrulation; gene repression; innovation; insight; knock-down; nanobodies; novel; physical property; physical state; protein complex; segregation; training opportunity; transcription factor; tumor

Project Summary: Precise control of cell-cell adhesion is critical for maintaining tissue integrity during development and in adult tissues. Abnormal activation of signals that regulate adhesion in tumors can result in epithelial-mesenchymal transition (EMT) and cancer metastasis, but we do not fully understand the mechanism through which these regulatory signals cause loss of adhesion. A proposed model for this process is transcriptional repression of cell adhesion genes: the EMT regulator Snail represses expression of the E- cadherin adhesion molecule, a core component of Adherens Junctions (AJs), and is thought to control adhesion in this manner. However, recent observations have shown that Snail regulates the stability and localization of AJs independent of transcriptional regulation of E-Cadherin levels. The specific mechanism by which Snail regulates AJ organization remains unknown, highlighting an important gap in our understanding of the signals that regulate adhesion and govern the cellular decision to undergo EMT. The long-term goal of this project is to determine how cell-cell adhesion is controlled during development to enable tissue morphogenesis and segregation of germ layers. The overall objective of this proposal is to identify mechanisms by which Snail regulates AJ organization during tissue remodeling events during embryonic development in Drosophila, and determine how this regulation contributes to a cell’s decision to undergo EMT. Preliminary data indicate that ectopic Snail expression causes a rapid shift in E-Cadherin protein localization from cell junctions to intracellular structures. Other observations have shown that cells in the Drosophila ventral furrow undergo junctional remodeling through Snail-dependent destabilization of AJs. Remarkably, this regulation occurs prior to depletion of maternally provisioned E-Cadherin protein, and is not inhibited by ectopic E-cadherin expression. Together these data indicate that Snail controls AJ organization through an additional post- transcriptional mechanism. The rationale for this proposed work is to gain insight not only into the nature of these mechanisms, but also the general principles governing cell adhesion during EMT events. Our central hypothesis is that Snail modulates adhesion by altering the stability and localization of junctional cadherin protein complexes through a mechanism independent of E-cadherin transcriptional regulation. This hypothesis will be tested by pursuing two specific aims: we will (1) identify the mechanism through which Snail affects AJ organization, and (2) define the physical conditions in which Snail can promote EMT in Drosophila epithelial tissues. Our approach is innovative because it is one of the first to examine the mechanistic basis of Snail- dependent shifts in cadherin localization, and further because it uses an integrative strategy that combines biochemical and cell biological approaches. The proposed research is significant because it is expected to advance our understanding of the post-transcriptional regulation of cell-cell adhesion, and may open new avenues of research for understanding cancer biology and developmental defects.

项目摘要：细胞细胞粘附的精确控制对于维持组织完整性至关重要 发育和成人组织。调节肿瘤粘合剂的信号异常激活可能导致 上皮间质转变（EMT）和癌症转移，但我们不完全了解机制 这些调节信号导致粘合剂丧失。这个过程的建议模型是 细胞粘附基因的转录表示：EMT调节器蜗牛表示E-的表达 钙粘蛋白粘附分子，粘附连接的核心成分（AJS），被认为可以控制 以这种方式粘附。但是，最近的观察结果表明，蜗牛调节稳定性和 AJ的定位独立于E-钙粘蛋白水平的转录调节。特定机制 蜗牛调节AJ组织仍然未知，强调了我们对 调节粘合剂并控制细胞决定EMT的信号。这个长期目标 项目将确定在发育过程中如何控制细胞细胞粘附以实现组织形态发生 和细菌层的隔离。该提议的总体目的是确定蜗牛的机制 调节果蝇胚胎发育期间组织重塑事件期间的AJ组织， 确定该法规如何促进单元进行EMT的决定。初步数据表明 异位蜗牛表达导致E-钙粘蛋白蛋白的定位迅速转移从细胞连接到 细胞内结构。其他观察结果表明，果蝇腹沟中的细胞经历 通过AJS的蜗牛依赖性不稳定的连接重塑。值得注意的是，此法规发生之前 耗尽主要提供的E-钙粘蛋白蛋白，并且不会被生态E-钙粘蛋白抑制 表达。这些数据一起表明蜗牛通过额外的后控制AJ组织 转录机制。这项拟议工作的理由是，不仅要洞悉 这些机制，以及在EMT事件期间管理细胞广告的一般原则。我们的中心 假设是蜗牛通过改变连接蛋白的稳定性和定位来调节粘附 蛋白质复合物通过独立于电子钙粘着蛋白转录调控的机制。这个假设 将通过追求两个具体目标来测试：我们将（1）确定蜗牛影响AJ的机制 组织，（2）定义蜗牛可以在果蝇上皮中促进EMT的物理条件 组织。我们的方法具有创新性，因为它是最早检查蜗牛机械基础的一种 依赖性钙粘蛋白定位的转变，进一步是因为它使用了结合的综合策略 生化和细胞生物学方法。拟议的研究很重要，因为它有望 促进我们对细胞电池广告的转录后调节的理解，并可能打开新的 了解癌症生物学和发育缺陷的研究途径。