STUDIES OF THE FOS ONCOGENE

FOS癌基因的研究

• 批准号: 6489342
• 负责人: TOM CURRAN
• 金额: $ 40.33万
• 依托单位: ST. JUDE CHILDREN'S RESEARCH HOSPITAL
• 依托单位国家: 美国
• 财政年份: 2000
• 资助国家: 美国
• 起止时间: 2000-01-01 至 2004-12-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6489342
• 关键词: cell transformation; embryonic stem cell; fos protein; gene expression; genetically modified animals; laboratory mouse; methylation; microarray technology; oncogenes; oxidation reduction reaction; point mutation; representational difference analysis

The discovery of oncogenes revolutionized analysis of the molecular bases of cancer. Oncogenes provided starting points for molecular dissection of the signaling pathways that govern normal cell growth and for elucidation of the events that lead to oncogenesis. The fos oncogene is responsible for induction of osteosarcomas and cell transformation by the Finkel-Biskis-Jinkins murine sarcoma virus. Its protein product, Fos, functions as a component of the inducible mammalian transcription factor AP 1. Induction of c-fos expression is associated with mitogenesis, differentiation, apoptosis and excitation of neurons. It is believed to participate in complex signal transduction networks that couple extracellular stimuli to long-term cellular responses by regulating gene expression. Transformation by fos is thought to be a consequence of inappropriate regulation of gene expression. Three major specific aims are addressed in this application. The first concerns the identification and characterization of fos target genes responsible for cell transformation by Representational Difference Analysis and cDNA array hybridization approaches. In the second specific aim we will follow up preliminary studies demonstrating that DNA 5-methylcytosine transferase-1 (dnmt1) is a fos target gene involved in cell transformation. We plan to identify genes that are methylated by dnmt1 in fos transformed cells and analyze their contribution to transformation. The third specific aim concerns the role of reduction/oxidation (redox) in the regulation of Fos function and cell growth. Previously, we demonstrated that the bifunctional redox/endonuclease gene, ref-1, regulates the DNA binding activity of Fos through a conserved cysteine residue in the DNA binding domain. Disruption of the Ref-1 gene in mice causes early embryonic lethality. We will introduce point mutations into Ref-1, by homologous recombination in embryonic stem cells that ablate the redox and nuclease functions of Ref-1 independently. These cells will be used to generate mutant mice and cell lines that will be used to analyze the role of Ref-1 in modulating AP1 activity and cell growth.

癌基因的发现彻底改变了对癌症分子碱基的分析。 致癌基因为控制正常细胞生长的信号通路和阐明导致肿瘤发生的事件提供了分子解剖的起点。 FOS癌基因负责通过Finkel-Biskis-Jinkins-Jinkins murine肉瘤病毒诱导骨肉瘤和细胞转化。 它的蛋白质产物FOS是诱导哺乳动物转录因子AP的组成部分。C-FOS表达的诱导与有丝分裂，分化，凋亡和神经元激发有关。 据信，它通过调节基因表达来参与复杂的信号转导网络，将细胞外刺激与长期细胞反应息息。 FOS的转化被认为是基因表达不当调节的结果。 在本应用程序中解决了三个主要的具体目标。 第一个涉及通过表示差异分析和cDNA阵列杂交方法来鉴定和表征负责细胞转化的FOS靶基因。 在第二个特定目的中，我们将跟进初步研究，该研究表明DNA 5-甲基环肽转移酶1（DNMT1）是参与细胞转化的FOS靶基因。 我们计划鉴定通过FOS转化细胞中DNMT1甲基化的基因，并分析其对转化的贡献。 第三个特定目的涉及还原/氧化（氧化还原）在FOS功能和细胞生长调节中的作用。以前，我们证明了双功能氧化还原/内切核酸酶基因Ref-1通过在DNA结合结构域中保守的半胱氨酸残基调节FOS的DNA结合活性。 小鼠Ref-1基因的破坏会引起早期胚胎致死性。 我们将通过在胚胎干细胞中的同源重组来将点突变引入Ref-1，从而消除Ref-1的氧化还原和核酸酶功能。 这些细胞将用于产生突变小鼠和细胞系，这些小鼠将用于分析REF-1在调节AP1活性和细胞生长中的作用。