CYP17A1 STRUCTURE FUNCTION, CRITICAL ENZYME IN HUMAN ANDROGEN BIOSYNTHESIS

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。 前列腺癌是最常见的癌症，也是美国男性癌症相关死亡的第二大原因。进展与雄激素的存在密切相关。传统的雄激素剥夺疗法显著减少前列腺组织中雄激素的产生，但不能抑制肾上腺雄激素的合成，在循环中留下基础水平的雄激素。细胞色素P450 17 A1（CYP 17 A1）负责在这两种组织中将双烯醇酮转化为雄激素。因此，CYP 17 A1的抑制提供了在前列腺癌治疗中完全剥夺雄激素的策略。几种CYP 17 A1抑制剂目前正在进行临床试验，但目前还没有关于CYP 17 A1的结构信息。缺乏CYP 17 A1晶体结构阻碍了对当前抑制剂如何工作以及如何改进它们的理解。本提案的目的是确定CYP 17 A1的结构。 了解CYP 17 A1及其配体之间的相互作用将提供有关这种酶如何发挥作用的信息。 我们的中心假设是，CYP 17 A1的晶体结构将揭示对应于该酶独特特征的特定相互作用。具体目标是：1）工程化CYP 17 A1的可溶形式，2）优化表达和纯化策略以产生mg量的纯的、稳定的、功能活性的、单分散的CYP 17 A1，其适合于结晶努力，和3）生长CYP 17 A1的衍射质量晶体。这项研究的预期成果是重要的类固醇生物合成酶CYP 17 A1的第一个晶体结构。这种结构将使配体结合模式的详细了解。

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. Prostate cancer is the most common occurring cancer and the second-leading cause of cancer-related death for men in the United States. Progression is strongly linked to the presence of androgens. Traditional androgen deprivation therapy significantly decreases androgen production in prostate tissue, but fails to inhibit adrenal androgen synthesis, leaving a basal level of androgens in circulation. Cytochrome P450 17A1 (CYP17A1) is responsible for the conversion of pregnenolone to androgens in both tissues. Thus, inhibition of CYP17A1 provides a strategy for complete deprivation of androgens in the treatment of prostate cancer. Several CYP17A1 inhibitors are currently in clinical trials, but there is currently no structural information about CYP17A1. The lack of a CYP17A1 crystal structure prevents an understanding of how current inhibitors work and how they might be improved. The objective of this proposal is to determine a structure of CYP17A1. Understanding the interaction between CYP17A1 and its ligands would provide information about how this enzyme functions. Our central hypothesis is that a crystal structure of CYP17A1 will reveal specific interactions that correspond to unique features of the enzyme. The specific aims are: 1) to engineer a soluble version of CYP17A1, 2) to optimize expression and purification strategies to generate mg quantities of pure, stable, functionally active, monodisperse CYP17A1 suitable for crystallization efforts, and 3) to grow diffraction-quality crystals of CYP17A1. The expected outcome of the proposed study is the first crystal structure of the important steroid biosynthetic enzyme CYP17A1. This structure will enable a detailed understanding of ligand binding modes.