Nano Accordions for Probing Biomolecular Interactions

描述(申请人提供)：蛋白质和脱氧核糖核酸(DNA)相互作用普遍存在，并在控制功能细胞系统和异常细胞转化(例如，肿瘤进展)方面发挥重要作用。当DNA和/或蛋白质结合时，由于需要形成新的复合体，DNA和/或蛋白质经常发生构象变化。我们假设，这些“分子力学”可以用人造分子手风琴来探测，分子手风琴由一串荧光发色团与可折叠铰链相连。分子构象的变化会对手风琴施加作用力，从而调节荧光发射的颜色。作为第一步，我们将使用固相合成来构建由荧光发色团和已知促进蛋白质结合的DNA序列组成的分子手风琴。手风琴-蛋白质相互作用将在体外进行，参数控制良好。我们的具体目标是设计和合成DNA上具有多个荧光发色团的分子手风琴，并在受控条件下应用荧光光谱和显微镜来测量蛋白质与DNA的相互作用。特别是，我们将从HMGA1蛋白开始，它是许多类型癌症的肿瘤转化和转移潜力的诊断标记物。在这个项目中，我们计划确定定义蛋白质-DNA-手风琴复合体形成范围的参数；这些参数将对分子手风琴未来在体内的应用至关重要。我们的长期目标是使用这些分子手风琴来探索体内的调节事件，并进一步了解疾病分子机制背后的异常细胞转化。

DESCRIPTION (provided by applicant): Protein and deoxyribonucleic acid (DNA) interactions are ubiquitous and play vital roles in controlling functional cellular systems and abnormal cell transformations (e.g., tumor progression). Upon binding, the DNA and/or proteins frequently undergo conformational changes due to the requirement of new complex formation. We hypothesize that these "molecular mechanics" can be probed with a man-made molecular accordion consisting of a string of fluorescent chromophores linked with foldable hinges. Molecular conformation changes will exert forces on the accordion, thereby tuning the fluorescent emission colors. As a first step, we will use solid phase synthesis to construct molecular accordions consisting of fluorescent chromophores and DNA sequences known to promote protein binding. The accordion-protein interactions will be carried out in vitro with wellcontrolled parameters. Our specific aims are to design and synthesize molecular accordions with multiple fluorescent chromophores on DNA and to apply fluorescent spectroscopy and microscopy in controlled conditions to gauge protein-DNA interactions. In particular, we will start with HMGA1 protein, which is a diagnostic marker for neoplastic transformation and metastatic potential of many type cancers. In this project, we plan to determine the parameters that define the scope of the formation of protein-DNA-accordion complex; these parameters will be essential for proposed future in vivo applications of molecular accordions. Our long-term objectives are to use these molecular accordions to probe regulatory events in vivo and to further our understanding of abnormal cell transformations underlying molecular mechanism of diseases.