TRANSFORMING GROWTH FACTOR B1

转化生长因子-β1(TGF-β1)属于 与细胞功能密切相关的多肽家族 调节活动。这种生长因子分子似乎是 与细胞生长和分化密切相关，以及 可能在这些细胞的自分泌调节中起着关键作用 流程。尽管许多研究都提出了重要的 转化生长因子-β1的细胞和生理功能 有关其结构/功能分析的信息已被 据报道。因此，我们目前对功能的理解 域和潜在的重要结构方面受到限制 到经典的蛋白质化学和cdna序列分析。这个 本提案的总体目标是定义和调查 具有重要生物学意义的转化生长因子-β1的结构特征 功能。为了实现这一目标，三种主要的DNA突变 框架插入、删除和站点定向中的方案 诱变，将用来产生一系列突变体 克隆的猿猴前-转化生长因子-β1多肽 Beta1cDNA.突变型转化生长因子-β1基因将在 哺乳动物组织培养细胞及其突变的转化生长因子-β1 生物化学和生物化学广泛分析的多肽 免疫化学技术。这些化验将解决这种影响 引入的遗传损伤对合成、成熟和 受体结合活性。我们将特别强调 蛋白水解物的成熟及潜伏生物的形成 可能发挥基础作用的复杂的转化生长因子-β1的性质 在活动调节中的作用。突变多肽也将 在标准生长中进行生物活性检测 增殖和抑制试验以及细胞 差异化系统。最后，对该基因的前体序列进行了分析 转化生长因子-β1多肽的表达将不依赖于 成熟生长因子及其相关生物活性 这一部分通过几种体外和体内生物测定进行评估。这个 以上提议的研究应该允许彻底的基因 转化生长因子-β1多肽的分离。除了……之外 确定重要的结构和功能域，这些 研究应针对转化生长因子的几个特征- β1，包括前体半胱氨酸的作用 转化生长因子-β的生物学功能的残基及其蛋白分解处理 Beta1。此外，从这些研究中获得的信息可能 确定对ITS至关重要的成熟生长因子区域 受体结合特性。

Transforming growth factor-beta-1 (TGF-beta1) belongs to a closely related family of polypeptides with potent cellular modulating activities. This growth factor molecule appears to be intimately associated with cell growth and differentiation, and may play pivotal roles in the autocrine regulation of these processes. Although numerous studies have addressed important cellular and physiological functions of TGF-beta1, essentially no information concerning its structure/function analysis have been reported. Consequently, our current understanding of functional domains and potentially important structural aspects is restricted to classical protein chemistry and cDNA sequence analysis. The overall objective of this proposal is to define and investigate structural features of TGF-beta1 important for biological function. To achieve this goal, three principle DNA mutagenesis schemes, in frame insertion, deletion, and site-directed mutagenesis, will be employed to generate a series of mutant TGF-beta1 polypeptides from the cloned simian pre-pro-TGF- beta1 cDNA. The mutant TGF-beta1 cDNA will be expressed in mammalian tissue culture cells and the altered TGF-beta1 polypeptides extensively analyzed by biochemical and immunochemical techniques. These assays will address the effect of the introduced genetic lesions on synthesis, maturation, and receptor binding activity. Particular emphasis will be placed on proteolytic maturation and on formation of a latent biological complex, properties of TGF-beta1 which may play fundamental roles in the regulation of activity. Mutant polypeptides will also be examined for biological activity in standard growth proliferation and inhibition assays as well as cellular differentiation systems. Finally, the precursor sequences of the TGF-beta1 polypeptide will be expressed independent of the mature growth factor and the biological activity associated with this portion assessed by several in vitro and in vivo bioassays. The above proposed studies should allow for a thorough genetic dissection of the TGF-beta1 polypeptide. In addition to identifying important structural and functional domains, these studies should address several characteristic features of TGF- beta1 including the role of the precursor, individual cysteine residues, and protelytic processing for biological function of TGF- beta1. Moreover, information obtained from these studies may identify regions of the mature growth factor essential for its receptor binding properties.