Regulation Epithelial Cell Growth by the Tight Junction

通过紧密连接调节上皮细胞生长

• 批准号: 6816761
• 负责人: VIVIAN TANG
• 金额: $ 13万
• 依托单位: HARVARD MEDICAL SCHOOL
• 依托单位国家: 美国
• 财政年份: 2004
• 资助国家: 美国
• 起止时间: 2004-07-01 至 2007-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6816761
• 关键词: antisense nucleic acid; apoptosis; biological signal transduction; cell cell interaction; cell cycle; cell growth regulation; cell line; gastrointestinal epithelium; gene expression; immunofluorescence technique; membrane proteins; molecular biology; protein localization; proteomics; tight junctions; transfection /expression vector; transmission electron microscopy

DESCRIPTION (provided by applicant): Epithelial cells have a built-in propensity to proliferate, which is essential for the normal turnover and renewal of tissues. To maintain a constant cell number, cell division and apoptosis must be tightly coupled. Disruption of this balance predisposes the epithleium to hyperproliferative disorders, including cancerous growth. A constitutive checkpoint of this balance is mediated by direct cell-cell interactions, which is the basis of contact-dependent inhibition of growth. However, despite intense investigations on this wellcharacterized phenomenon, little is known about the relative contribution of different cell-cell interactions to contact-regulated epithelial cell growth. The TIGHT JUNCTION is an intercellular interaction that is universally found in all epithelial cells, but whose function in cell proliferation is almost completely unknown. The current proposal is designed to address the fundamental question of whether the TIGHT JUNCTION is directly involved in active cell-cell signaling events that lead to downstream regulation of cell growth control. The specific aims of the current proposal are:(1) to directly assess the roles of the TIGHT JUNCTION in epithelial cell growth by systematic investigation of cell-cycle checkpoints and apoptosis-related events in TIGHT JUNCTION disrupted cells.(2) to comprehensively identify the molecular players at the TIGHT JUNCTION.(3) to analyze molecular mechanisms of action that relay TIGHT JUNCTION information to downstream cell-cycle and apoptosis pathways. T84 and HT-29 cell lines will be used as in vitro model systems for this project because they retain key functional characteristics of the intestinal epithelium including formation of intercellular junctions, generation of a polarized phenotype, exhibition of contact-inhibition of growth, responsiveness to cytokines and infectious agent. The functional roles of TIGHT JUNCTION will be studied by disruption of the TIGHT JUNCTION using anti-sense technology. The molecular composition of TIGHT JUNCTION will be characterized via a proteomics approach. The functions of novel TIGHT JUNCTION proteins in cell growth control will be analyzed systematically in parental and tight junction disrupted cells.

描述（由申请人提供）： 上皮细胞具有增殖的内置倾向，这对于正常的周转率和组织的更新至关重要。为了保持恒定的细胞数，必须紧密耦合细胞分裂和凋亡。这种平衡的破坏使上皮易于超增殖性疾病，包括癌性生长。该平衡的本构检查点是由直接细胞 - 细胞相互作用介导的，这是接触依赖性抑制生长的基础。然而，尽管对这种良好的现象进行了激烈的研究，但对不同细胞 - 细胞相互作用对接触调节的上皮细胞生长的相对贡献知之甚少。 紧密连接是一种在所有上皮细胞中普遍发现的细胞间相互作用，但在细胞增殖中的功能几乎完全未知。当前的建议旨在解决紧密连接是否直接参与活性细胞信号事件的基本问题，从而导致细胞生长控制的下游调节。 当前建议的具体目的是：（1）通过系统地研究细胞周期检查点和与凋亡相关的事件的系统研究，直接评估紧密连接在上皮细胞生长中的作用。途径。 T84和HT-29细胞系将用作该项目的体外模型系统，因为它们保留了肠上皮的关键功能特征，包括形成细胞间连接，产生偏振表型，表现出生长的接触抑制，对细胞因子和感染剂的影响。紧密连接的功能作用将通过使用反义技术的紧密连接来研究。紧密连接的分子组成将通过蛋白质组学方法来表征。新型紧密连接蛋白在细胞生长控制中的功能将在父母和紧密连接破坏的细胞中进行系统分析。