Signaling Mechanisms of EphrinB1 in Cell Adhesion, Migration and Invasion

EphrinB1 在细胞粘附、迁移和侵袭中的信号机制

基本信息

批准号：
8552901
负责人：
Ira Daar
金额：
$ 63.65万
依托单位：
DIVISION OF BASIC SCIENCES - NCI
依托单位国家：
美国
项目类别：
财政年份：
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/8552901
关键词：
Adhesions Affect Biochemical Biological Models Breast Cancer cell line Cell Adhesion Cell Fate Control Cell Line Cell Lineage Cell Polarity Cell physiology Cell-Cell Adhesion Cells Colon Complex Data Development Developmental Process Disease Disseminated Malignant Neoplasm Distal Embryo Embryonic Development Environment Eph Family Receptors Ephrins Epithelial Cells Event Family Family member Fibroblast Growth Factor Receptors Histologic Human Intercellular Junctions Investigation Laboratories Ligands Malignant Neoplasms Maps Mediating Monomeric GTP-Binding Proteins Morphogenesis Movement Neoplasm Metastasis Neuroblastoma Ovarian Pathway interactions Play Process Prostate Protein Tyrosine Kinase Proteins Rana Receptor Protein-Tyrosine Kinases Research Role Signal Transduction Signal Transduction Pathway Signaling Molecule System Therapeutic Intervention Tight Junctions Tissues Visual Fields Work Xenopus Xenopus oocyte angiogenesis cell motility improved insight intercellular communication interest loss of function lung melanoma member migration mutant neoplastic protein complex receptor research study retinal progenitor cell tumorigenesis

项目摘要

Our current research interests are aimed toward examining the mechanism by which Eph receptor tyrosine kinases and their ephrin ligands signal events affecting cell-cell adhesion and morphogenetic movements. From the elucidation of these signal transduction pathways we may improve our understanding of oncogenesis. The cell-cell adhesion system plays a major role in normal development and morphogenesis. Inactivation of this adhesion system is thought to play a critical role in cancer invasion and metastasis. The Xenopus embryo is well suited for investigations of these processes because the frog has a well characterized and invariant cell fate map and cell lineage can be easily traced during experiments. Mutant receptors, ligands, and other proteins can be ectopically expressed in embryos. Thus, their effects on signal transduction, motility, and differentiation can be assessed morphologically and histologically as well as biochemically in a developing vertebrate. Our laboratory is currently investigating the role of the Xenopus Eph receptor tyrosine kinases and ephrinB transmembrane ligands in cell signaling and function using the Xenopus oocyte and embryo systems, as well as human cultured cell lines. At present, our emphasis is placed upon the mechanism by which these Eph family members send signals affecting morphogenetic movements. Members of the Eph family have been implicated in regulating numerous developmental processes and have been found to be de-regulated in metastatic cancers, for example, prostate, ovarian, breast, colon, neuroblastoma, lung, and melanoma.Our laboratory has continued these studies examining proximal and distal signaling from ephrinB1 that controls cell adhesion and cell movement. We recently found evidence that ephrinB1 signals via its intracellular domain to control retinal progenitor movement into the eye field by interacting with Dishevelled (dsh), and co-opting the planar cell polarity (PCP) pathway. Using biochemical analysis and gain or loss of function experiments, our data suggest that dsh associates with ephrinB1 and mediates ephrinB1 signaling via downstream members of the PCP pathway during eye field formation. thus, we have used the eye field as a model system for understanding how ephrinB1 controls cell movement.Most recently we have examined the mechanisms by which ephrinB1 affects cell-cell junctions. A body of evidence is emerging that shows a requirement for ephrin ligands in the proper migration of cells, and the formation of cell and tissue boundaries. These processes are dependent on the cellcell adhesion system, which playsa crucial role in normal morphogenetic processes duringdevelopment, as well as in invasion and metastasis19. AlthoughephrinB ligands are bi-directional signalling molecules, theprecise mechanism by which ephrinB1 signals through itsintracellular domain to regulate cell-cell adhesion in epithelialcells remains unclear. Here, we present evidence that ephrinB1associates with the Par polarity complex protein Par-6 (ascaffold protein required for establishing tight junctions) andcan compete with the small GTPase Cdc42 for association withPar-6. This competition causes inactivation of the Par complex,resulting in the loss of tight junctions. Moreover, the interactionbetween ephrinB1 and Par-6 is disrupted by tyrosinephosphorylation of the intracellular domain of ephrinB1. Thus,we have identified a mechanism by which ephrinB1 signallingregulates cell-cell junctions in epithelial cells, and this mayinfluence how we devise therapeutic interventions regardingthese molecules in metastatic disease.

我们目前的研究兴趣旨在检查EPH受体酪氨酸激酶及其ephrin配体的机制，影响细胞细胞粘附和形态发生运动。通过阐明这些信号转导途径，我们可以提高对肿瘤发生的理解。细胞 - 细胞粘附系统在正常发育和形态发生中起主要作用。人们认为这种粘附系统的失活在癌症侵袭和转移中起着至关重要的作用。爪蟾胚胎非常适合研究这些过程，因为青蛙具有良好的特征和不变的细胞命运图和细胞谱系，可以在实验过程中很容易追溯。突变体受体，配体和其他蛋白质可以在胚胎中表达。因此，它们对信号转导，运动性和分化的影响可以在形态学和组织学上以及在发育中的脊椎动物中在生化上进行评估。我们的实验室目前正在研究使用异爪蟾卵母细胞和胚胎系统以及人类培养的细胞系在细胞信号和功能中研究爪蟾EPH受体酪氨酸激酶和Ephrinb跨膜配体的作用。目前，我们的重点放在这些EPH家族成员发出影响形态发生运动的信号的机制上。 EPH家族的成员与调节大量发育过程有关，并被发现在转移性癌症中被脱离调节，例如前列腺，卵巢，乳腺，结肠，神经母细胞瘤，肺和黑色素瘤。您的实验室继续进行这些研究，这些研究检查了Ephrinb1细胞和细胞的近距和远距离信号的研究。我们最近发现，埃菲林布1通过其细胞内结构域发出信号，以通过与散色（DSH）相互作用并选择平面细胞极性（PCP）途径来控制视网膜祖细胞的运动。我们的数据使用生化分析以及功能实验的增益或丧失，表明DSH与ephrinb1相关并通过PCP途径的下游成员在眼场形成期间通过PCP途径的下游成员介导Ephrinb1信号。因此，我们已经将眼场用作模型系统来了解ephrinb1如何控制细胞运动。最近，我们研究了ephrinb1影响细胞细胞连接的机制。出现了一大批证据，该证据表明在适当的细胞迁移以及细胞和组织边界的形成中对埃弗林配体的需求。这些过程取决于细胞细胞粘附系统，该系统在开发过程中以及在侵袭和转移过程中在正常形态发生过程中发挥了至关重要的作用。虽然ephrinb配体是双向信号分子，但ephrinb1通过其内部细胞域信号以调节上皮细胞中细胞细胞粘附的原理机制尚不清楚。在这里，我们提供了证据表明，ephrinb1sosociat与Par-parmity复合蛋白PAR-6（建立紧密连接所需的Ascaffold蛋白）并与小的GTPase CDC42竞争，以与PAR-6缔合。这场竞争会导致PAR复合体失活，导致连接紧密的连接损失。此外，埃菲林布1和PAR-6之间的相互作用被埃菲林布1的细胞内结构域的酪氨酸磷酸化所破坏。因此，我们已经确定了一种机制，通过这种机制，ephrinb1 signallingnegringnegrignnegnnegrence of ephrinb1在上皮细胞中的细胞 - 细胞连接处，并且这种可能是我们如何设计有关这些转移性疾病分子的治疗干预措施。