LTBP-2--STRUCTURAL AND REGULATORY FUNCTIONS

LTBP-2--结构和监管功能

• 批准号: 6527162
• 负责人: J MICHAEL SHIPLEY
• 金额: $ 10.45万
• 依托单位: BARNES-JEWISH HOSPITAL
• 依托单位国家: 美国
• 财政年份: 1998
• 资助国家: 美国
• 起止时间: 1998-08-07 至 2004-02-28
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6527162
• 关键词: binding proteins; elastic tissue; extracellular matrix; fibrillin; gene targeting; genetically modified animals; immunoelectroadsorption; immunofluorescence technique; immunoprecipitation; in situ hybridization; laboratory mouse; lethal genes; mammalian embryology; microfilaments; protein binding; protein isoforms; protein localization; protein structure function; transforming growth factors

DESCRIPTION: Latent TGF-b binding protein-2 (LTBP-2) is one of four LTBPs, and shares a high degree of identity with fibrillin, a major component of extracellular microfibrils. LTBP-2 has been shown in bovine systems to be an integral component of elastic microfibrils. In humans, mutations in LTBP-2 are associated with a disease sharing similarities with the Marfan syndrome, characterized by skeletal and vascular abnormalities. As its name indicates, LTBP-2 is also a TGF-b binding protein, and may regulate the activity of TGF-bs. In this proposal, the proposed dual function of LTBP-2 will be examined. We have created a targeted deletion in the mouse LTBP-2 gene, eliminating its expression. Mice homozygous for this mutation have an embryonic lethal phenotype. We will ultimately examine the basis for this lethal phenotype. First, we will do several experiments designed to investigate the association of LTBP-2 with microfibrils vs. TGF-b in the developing and adult mouse. The association of LTBP-2 with elastic fibers in the normal mouse will be investigated in situ hybridization and immunolocalization. Association of TGF-b with microfibrils will be examined as well. The LTBP-2/TGF-b interaction will also be investigated. Again, in situ hybridization will be used to determine the spatial and temporal coexpression of LTBP-2 with TGF-b1, -b2 and -b3 in the developing and adult mouse. The specific interaction of LTBP-2 and individual TGF-b isoforms will be investigated in primary explanted murine tissue cultures, and by co-transfection in mammalian expression systems. The binding site on LTBP-2 for TGF-bs will be determined using the same transfection systems. Having defined when and where LTBP-2 is associated with microfibrils vs. TGF-b, we will then examine the basis for the lethal phenotype of the LTBP-2 knockout mouse. Properties of microfibrils will be examined in LTBP-2 -/- embryos, as will the activation state of TGF-b in these embryos. Finally, we will assess whether LTBP-1 can functionally substitute for LTBP-2 in the developing mouse.

描述：潜在的TGF-B结合蛋白2（LTBP-2）是四个 LTBPS，并与原纤维蛋白具有高度的身份 细胞外微纤维的成分。 LTBP-2已显示在 牛系统是弹性微纤维的组成部分。 在 人类，LTBP-2中的突变与疾病共享有关 与Marfan综合征的相似性，其特征是骨骼和 血管异常。 顾名思义，LTBP-2也是TGF-B 结合蛋白，并可能调节TGF-BS的活性。 在这个 提案，将检查LTBP-2的拟议双重函数。 我们 在鼠标LTBP-2基因中创建了目标删除，消除了 它的表达。 该突变纯合子的小鼠具有胚胎 致命表型。 我们最终将检查这种致命的基础 表型。 首先，我们将进行几个设计的实验 研究LTBP-2与微纤维与TGF-B的关联 发展和成年小鼠。 LTBP-2与弹性的关联 正常小鼠中的纤维将进行原位杂交 和免疫定位。 TGF-B与微纤维的关联将是 也检查了。 LTBP-2/TGF-B相互作用也将是 调查。 同样，原位杂交将用于确定 LTBP -2与TGF -B1，-b2和-b3的空间和时间共表达 在发展中心和成年小鼠中。 LTBP-2的特定相互作用 并且将在主要的外植体中研究单个TGF-B同工型 鼠组织培养物，并通过共转染哺乳动物表达 系统。 LTBP-2上的结合位点将用于TGF-BBS 相同的转染系统。 定义了LTBP-2在何时何地 与微纤维与TGF-B相关，然后我们将检查基础 对于LTBP-2基因敲除小鼠的致命表型。 属性 微纤维将在LTBP-2 - / - 胚胎中检查， 这些胚胎中TGF-B的激活状态。 最后，我们将评估 LTBP-1是否可以在发育中功能替代LTBP-2 老鼠。