ACTIVE CONFORMATION OF LAMININ PEPTIDE 11

67 kDa高亲和力层粘连蛋白结合蛋白(LBP)是一种细胞 与其表达呈正相关的表面蛋白 在许多实体肿瘤中进展。这种相关性很可能是由于 该蛋白质介导高亲和力相互作用的能力 基底膜层粘连蛋白分子的转移性肿瘤细胞。 LBP的主要配体结合区位于层粘连蛋白-1中 COPGYIGSR(肽11)上的B链。调查人员已经 初步数据(来自核磁共振Tr-NOESY实验) 肽11与分离的67 kDa LBP结合时的构象，但 实验一直受到可用LBP数量较少的限制。 研究人员不能用他们的中文产生足够的蛋白质 用于常规核磁共振的仓鼠卵巢(CHO)过表达系统 实验，在本提案中，他们计划完成核磁共振 LBP结合多肽11的结构研究。调查人员 还将继续对有希望的环状类似物进行结构研究 多肽11.这些多肽本身在 血流和适度亲和力，而非肽结构 仿制药有望显著改善药理作用 特点。这种模拟物可以提供非常有用的佐剂 恶性实体肿瘤的治疗。这项工作的长期目标 是利用多肽11的活性构象，当它结合到 67 kDa LBP，作为基于结构的新型抗震剂设计的模板 转移药物。然而，这需要发展一种非常 准确的模板结构是目前研究中概述的 应用程序将产生。调查人员还将进行一项 用一系列实验来增加我们对生物化学的认识 以及LBP的膜结合形式的作用机制。 这些实验将使用我们的基于多肽11的光标记探针 为了便于鉴定与之相互作用的LBP残基 多肽11.其他实验将评估67 KDA LBP在组织中可能与a6b1整合素协同作用 入侵。

The 67 kDa high affinity laminin binding protein (LBP) is a cell surface protein whose expression shows a positive correlation with progression in many solid tumors. This correlation likely results from the ability of the protein to mediate high affinity interactions of a metastatic tumor cells with basement membrane laminin molecules. The major ligand binding domain for the LBP occurs in the laminin-1 b chain at the COPGYIGSR (peptide 11) site. The investigators have preliminary data (from NMR Tr-NOESY experiments) on the conformation of peptide 11 when bound to isolated 67 kDa LBP, but experiments have been restricted by the low amount of available LBP. The investigators can not produce sufficient protein from their chinese hamster ovary (CHO) overexpression system for routine NMR experiments, and, in the present proposal, they plan to complete NMR structural studies on peptide 11 bound to the LBP. The investigators will also pursue structural studies on promising cyclic analogs of peptide 11. The peptides, themselves, have very short lifetimes in the blood stream and modest affinity, whereas non-peptide structural mimetics are expected to have significantly improved pharmacological characteristics. Such mimetics could provide extremely useful adjuvant therapies for malignant solid tumors. The long range goal of the work is to use the active conformation of peptide 11, when it is bound to the 67 kDa LBP, as a template for structure-based design of novel anti- metastatic drugs. This, however, requires the development of a very accurate template structure which the studies outlined in the current application would produce. The investigators will also undertake a series of experiments to increase our knowledge of the biochemistry and mechanism of action of the membrane associated form of the LBP. These experiments will use our peptide 11 based photolabelling probe to facilitate identification of the LBP residues which interact with peptide 11. Other experiments will evaluate the postulate that the 67 kDa LBP may act in concert with the a6b1 integrin during tissue invasion.