Orphan Nuclear Receptors in Development and Physiology

发育和生理学中的孤儿核受体

• 批准号: 6946083
• 负责人: HOLLY A. INGRAHAM
• 金额: $ 44.37万
• 依托单位: UNIVERSITY OF CALIFORNIA, SAN FRANCISCO
• 依托单位国家: 美国
• 财政年份: 1993
• 资助国家: 美国
• 起止时间: 1993-08-01 至 2008-03-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6946083
• 关键词: biological signal transduction; cell line; cofactor; gene expression; histogenesis; hormone regulation /control mechanism; immunocytochemistry; in situ hybridization; laboratory mouse; laboratory rat; ligands; mitogen activated protein kinase; northern blottings; nuclear receptors; phosphorylation; physiology; polymerase chain reaction; posttranslational modifications; protein protein interaction; southern blotting; steroid hormone; terminal nick end labeling; transcription factor; transfection; western blottings

DESCRIPTION (provided by applicant): Published studies from several labs, including our own, have demonstrated essential roles for the orphan nuclear receptor, Steriodigenic factor 1 (SF-1) in endocrine organogenesis, male sexual differentiation, and steroid homeostasis. Our prior work shows that maximal SF-1 mediated transcription and recruitment of general cofactors depends on a single phospho-serine 203 located in the hinge region, and that receptor phosphorylation mimics several features of ligand-dependent receptor activation. Here, we propose to: Aim 1 Determine the in vivo role of SF-1 serine 203 phosphorylation. Aim 2 Identify cofactors that are recruited upon SF-1 phosphorylation by using a yeast genetic screen, an affinity-GST purification method, or a high-throughput peptide binding assay. Aim 3 Establish the function and dynamics of cofactor recruitment for identified candidates. The potential role for phosphorylation in regulating nuclear receptor activity has been provocative, but remained secondary to ligand-activation of receptors. Now, because some members of the nuclear receptor gene family may not have specific high affinity ligand, post-translational events and protein-protein interactions have assumed a more legitimate position in modulating receptor activity. To date, studies addressing how extracellular signaling and nuclear receptor function are integrated have been limited to cellular model systems. As such, our aim to assess the in vivo function of SF-1 phosphorylation will be of significance. Our preliminary data show that SF-1 is phosphorylated at S203 in endocrine tissue; these observations provide a strong rationale for using mouse genetics to determine the in vivo significance of this modification. We are also excited by our new finding that the UBC-9 SUMOylation conjugating enzyme interacts with SF-1. Indeed, the close proximity of the MAPK phosphorylation site to the perfect SUMOylation consensus site in the hinge region of SF-1 is provocative, and warrants further investigation into the possible interplay between these two posttranslational events. We believe our studies with SF-1 will provide valuable insights into how posttranslational events modulate ligand-independent receptor activation and will be directly relevant to the progression of hormone-insensitive endocrine tissue cancers.

描述（由申请人提供）：包括我们自己的多个实验室的已发表研究表明了孤儿核受体，静脉性因子1（SF-1）在内分泌器官发生，男性性别分化和类固醇稳态中的重要作用。 我们先前的工作表明，最大的SF-1介导的转录和一般辅助因子的募集取决于位于铰链区域的单个磷酸丝氨酸203，并且受体磷酸化模拟了配体依赖性受体激活的几个特征。 在这里，我们建议：AIM 1确定SF-1丝氨酸203磷酸化的体内作用。 AIM 2通过使用酵母遗传筛选，亲和力GST纯化方法或高通​​量肽结合测定法，识别在SF-1磷酸化时募集的辅助因子。 AIM 3建立了确定的候选者的辅助因子募集的功能和动力学。 磷酸化在调节核受体活性中的潜在作用是挑衅性的，但仍然是受体配体激活的继发性。 现在，由于核受体基因家族的某些成员可能没有特定的高亲和力配体，因此翻译后事件和蛋白质 - 蛋白质相互作用已在调节受体活性中具有更合法的位置。 迄今为止，针对细胞外信号传导和核受体功能的研究的研究仅限于细胞模型系统。 因此，我们的目的是评估SF-1磷酸化的体内功能的意义。 我们的初步数据表明，SF-1在内分泌组织中在S203处磷酸化。这些观察结果为使用小鼠遗传学确定这种修饰的体内意义提供了有力的理由。 我们的新发现，UBC-9 sumoylation共轭酶与SF-1相互作用也感到兴奋。 实际上，MAPK磷酸化位点与SF-1铰链区域的完美Sumoylation共识位点的密切接近是挑衅性的，并且值得进一步研究这两个翻译后事件之间可能的相互作用。 我们认为，我们对SF-1的研究将为翻译后事件如何调节配体无关受体激活提供宝贵的见解，并将与激素不敏感的内分泌组织癌的进展直接相关。