Glucocorticoid Regulation of NF-kB Function by O-GlcNAc

O-GlcNAc 糖皮质激素对 NF-kB 功能的调节

• 批准号: 7117216
• 负责人: Xiaoyong Yang
• 金额: $ 5.2万
• 依托单位: SALK INSTITUTE FOR BIOLOGICAL STUDIES
• 依托单位国家: 美国
• 财政年份: 2004
• 资助国家: 美国
• 起止时间: 2004-09-01 至 2007-08-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7117216
• 关键词: RNA interference; biochemistry; biological signal transduction; chromatin immunoprecipitation; corticosteroid receptors; enzyme activity; gene induction /repression; glycosyltransferase; immune response; immunoregulation; inflammation; nuclear factor kappa beta; postdoctoral investigator; protein protein interaction; transfection; RNA interference; biochemistry; biological signal transduction; chromatin immunoprecipitation; corticosteroid receptors; enzyme activity; gene induction /repression; glycosyltransferase; immune response; immunoregulation; inflammation; nuclear factor kappa beta; postdoctoral investigator; protein protein interaction; transfection

DESCRIPTION (provided by applicant): NF-kappaB-induced activation of proinflammatory genes can be completely repressed by the glucocorticoid receptor upon hormone binding. However, critical cofactors and mechanism that transmit the glucocorticoid signal into the NF-kappaB pathway remain elusive. We recently defined O-GIcNAc transferase (OGT) as an atypical mediator in gene repression. Hence, our first specific aim is to explore the role of this enzyme as a candidate corepressor for the glucocorticoid receptor in antiinflammatory responses. We will test a physical interaction between OGT and the glucocorticoid receptor by biochemical approaches and will examine their functional interaction by cell-based gene reporter assays. Using RNA interference, we will assess a possible role of OGT in regulating endogenous proinflammatory genes. Unlike OGT, little is known about the impact of the opposing enzyme O-Incase (OGN) on transcription. Hence, our second specific aim is to discern how these two reciprocal enzymes contribute to the activation or inhibition of the proinflammatory genetic network. Using a chromatin immunoprecipitation assay, we will study the dynamics of OGT and OGN at the promoters of either active or repressive proinflammatory genes. Moreover, we will seek to identify upstream regulators and downstream targets of these two enzymes in the transcriptional apparatus through biochemical approaches. This study is designed to delineate a precise mechanism by which O-GIcNAc regulates transcription. As glucocorticoids are currently used to treat inflammation and cancer, understanding their action via O-GIcNAc offers a new approach to treatment and drug designs.

描述（由申请人提供）：激素结合后，糖皮质激素受体可以完全抑制NF-kappab诱导的促炎基因的激活。但是，将糖皮质激素信号传播到NF-kappab途径中的临界辅助因子和机制仍然难以捉摸。我们最近将O-GICNAC转移酶（OGT）定义为基因抑制中的非典型介体。因此，我们的第一个具体目的是探索该酶作为抗炎反应中糖皮质激素受体的候选核压球的作用。我们将通过生化方法测试OGT与糖皮质激素受体之间的物理相互作用，并将通过基于细胞的基因报告基因测定法检查它们的功能相互作用。使用RNA干扰，我们将评估OGT在调节内源性促炎基因中的可能作用。与OGT不同，对相反酶O-INCASE（OGN）对转录的影响知之甚少。因此，我们的第二个具体目的是辨别这两种互相酶如何促进促炎遗传网络的激活或抑制。使用染色质免疫沉淀测定法，我们将研究活性或抑制性促炎基因启动子的OGT和OGN的动力学。此外，我们将寻求通过生化方法在转录设备中这两种酶的上游调节剂和下游靶标。这项研究旨在描述O-GICNAC调节转录的精确机制。由于目前使用糖皮质激素来治疗炎症和癌症，因此通过O-GICNAC了解其作用提供了一种新的治疗方法和药物设计方法。