CHEMICAL SYNTHESIS & TARGET IDENTIFICATION OF CERATOSPONGAMIDE

这个子项目是许多利用资源的研究子项目之一 由NIH/NCRR资助的中心拨款提供。子项目的主要支持 而子项目的主要调查员可能是由其他来源提供的， 包括其它NIH来源。 列出的子项目总成本可能 代表子项目使用的中心基础设施的估计数量， 而不是由NCRR赠款提供给子项目或子项目工作人员的直接资金。 炎症性和自身免疫性疾病，如哮喘和类风湿性关节炎，其特征在于免疫细胞的积累，这些免疫细胞响应于一系列复杂的分泌信号分子而引起组织损伤。 被认为是炎症的关键介质的两种细胞因子是IL-1b和TNF-α。 这些细胞因子主要通过改变基因表达模式对靶组织产生不同但重叠的作用。 IL-1b和TNF-α通过与不同的细胞表面受体结合来控制基因表达，从而激活多个蛋白激酶级联。 我们提出了一种药理学方法来研究这些复杂的信号通路。 我们的想法来自于最近发现的一种海洋天然产物ceratospongamide，有效抑制IL-1b诱导的基因表达，IC 50为32 nM。 我们试图阐明其作用机制。 Ceratosponamide是一种大环七肽，其在构象上受到两个额外环（噻唑和恶唑啉）的限制，这两个额外环是通过半胱氨酸和苏氨酸侧链环化到肽骨架上形成的。 我们将合成ceratospongamide和衍生物，这将使其细胞目标的识别。 用于亲和纯化的放射性标记的和固定的衍生物都将使用现代合成方法来合成。 在UCSF设施获得的质谱测量将是必不可少的，原因有两个：（1）表征合成中间体和（2）确定ceratospongamide的蛋白质目标。

This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. Primary support for the subproject and the subproject's principal investigator may have been provided by other sources, including other NIH sources. The Total Cost listed for the subproject likely represents the estimated amount of Center infrastructure utilized by the subproject, not direct funding provided by the NCRR grant to the subproject or subproject staff. Inflammatory and autoimmune diseases, such as asthma and rheumatoid arthritis, are characterized by the accumulation of immune cells that cause tissue damage in response to a complex array of secreted signaling molecules. Two cytokines thought to be critical mediators of inflammation are IL-1b and TNF-a. These cytokines exert distinct yet overlapping effects on target tissues, primarily by altering patterns of gene expression. IL-1b and TNF-a control gene expression by binding to distinct cell surface receptors, whereupon multiple protein kinase cascades are activated. We propose a pharmacological approach to study these complex signaling pathways. Our idea derives from the recent discovery that a marine natural product, ceratospongamide, potently inhibits gene expression induced by IL-1b with an IC50 of 32 nM. We seek to elucidate its mechanism of action. Ceratospongamide is a macrocyclic heptapeptide that is conformationally constrained by two additional rings (thiazole and oxazoline) formed by the cyclization of cysteine and threonine side chains onto the peptide backbone. We will synthesize ceratospongamide and derivatives that will enable the identification of its cellular targets. both radiolabeled and immobilized derivatives for affinity purification will be synthesized using modern synthetic methodology. Mass spectrometry measurements obtained at the UCSF Facility will be essential for two reasons: (1) characterizing synthetic intermediates and (2) identifying ceratospongamide's protein target.