A MULTIDISCIPLINARY APPROACH TO PEPTIDE-BASED ANTAGONISTS OF PCNA

这个子项目是许多研究子项目中利用 资源由NIH/NCRR资助的中心拨款提供。子项目和 调查员(PI)可能从NIH的另一个来源获得了主要资金， 并因此可以在其他清晰的条目中表示。列出的机构是 该中心不一定是调查人员的机构。 细胞增殖依赖于细胞内和细胞外的多价相互作用。论小说的发展 治疗疾病的方法需要开发利用多价药物的效应剂和抑制剂 细胞增殖过程中众多过程的基础。新型高效多价配体的研究进展 蛋白质、DNA和细胞表面需要一个多学科的方法，其中包括(A) 针对各个结合位点的优化配基；(B)能够高度精确地分离的间隔区元件 在靶上的多个位置优化相互作用的单价配体，以最大限度地提高有利 没有引入通常观察到的显著的熵或热罚 以及(C)连接方法，以精确地连接多个配体和间隔物 举止。在这个子项目中，我们描述了一种多学科方法来开发新的基于多肽的 增殖细胞核抗原的拮抗剂。增殖细胞核抗原是一种三聚体蛋白质，是一种 通过与包括复制DNA在内的多种蛋白质相互作用而调节细胞增殖 聚合酶。抑癌基因p21通过与增殖细胞核抗原结合并阻止其他细胞蛋白发挥作用 无法访问增殖细胞核抗原。我们正在开发一种方法，通过一种 采用以下具体目标的多学科方法：(1)开发新的增殖细胞核抗原 用噬菌体展示和从环肽文库中提取配体；(2)增殖细胞核抗原检测方法的建立 DNA聚合酶活性的结合和拮抗；(3)二价和三价抑制剂的发展 通过开发能够最佳地将多个配体放置在 增殖细胞核抗原和防止增殖细胞核抗原与其他细胞靶点相互作用。这种方法，其中单个配体， 间隔基和连接体元件被快速结合以确定优化的配体，正被用作模型 开发新类别的抑制剂的系统，面向未来应用，作为一种一般方法 控制细胞通讯和细胞增殖。从广泛的角度来看，这项工作将开发新的方法 为了理解和控制细胞之间和细胞内的交流，这在炎症中很重要， 癌症、细菌感染和组织再生。这些方法将有需要理解的应用程序 在疾病的起因和开发新的有效的疾病治疗方法方面。

This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. Cell proliferation depends on intracellular and extracellular polyvalent interactions. The development of novel approaches to treat diseases requires the development of effectors and inhibitors that exploit the polyvalent basis of numerous processes in cell proliferation. The development of effective polyvalent ligands for proteins, DNA, and cell surfaces requires a multidisciplinary approach that includes the combination of (a) optimized ligands for the individual binding sites; (b) spacer elements capable of highly precisely separating the monovalent ligands for optimized interaction at multiple sites on the target to maximize favorable enthalpy and entropy without introducing the significant entropic or enthalpic penalties commonly observed in polyvalency; and (c) ligation methodologies to link the multiple ligand and spacer elements in a precise manner. In this subproject, we describe a multidisciplinary approach to develop novel peptide-based antagonists of the proliferating cell nuclear antigen (PCNA). PCNA is a trimeric protein that is a master regulator of cell proliferation via its interactions with numerous proteins including the replicative DNA polymerase. The tumor suppressor p21 functions by binding to PCNA and preventing other cellular proteins from accessing PCNA. We are developing approaches to achieve highly effective ligands of PCNA via a multidisciplinary approach that employs the following specific aims: (1) The development of novel PCNA ligands by peptide phage display and from cyclic peptide libraries; (2) the development of assays of PCNA binding and antagonism of DNA polymerase activity; (3) the development of bivalent and trivalent inhibitors of PCNA via the development of novel spacers and linkers capable of optimally placing multiple ligands on PCNA and preventing PCNA interaction with other cellular targets. This approach, in which individual ligand, spacer, and linker elements are rapidly combined to identify optimized ligands, is being used as a model system for the development of new classes of inhibitiors, toward future application as a general approach to control cell communication and cell proliferation. Broadly considered, this work will develop new approaches to understand and control communication between cells and within cells, which is important in inflammation, cancer, bacterial infection, and tissue regeneration. These approaches will have applications to understand the causes of disease and in the development of novel and effective treatments for disease.