TRANSCRIPTION CONTROL BY THE NUCLEAR ONCOPROTEIN, E1A

这项提案的长期目标是阐明转录 调节途径也是致癌基因作用的靶点，例如 腺病毒ElA。 已经鉴定出几种癌基因产物。 这些癌基因产物的生化功能的测定 最终将阐明导致转化的途径， 肿瘤发生 越来越多的证据表明， 癌基因产物参与基因表达的控制。 这 建议涉及ElA癌基因产物的功能分析， 考虑到它们对细胞蛋白活性的影响， E2 F、E4 F和E2 FBP。 E2 F和E4 F是细胞转录因子， 参与腺病毒早期基因的控制。 E2 FBP是一个 一种通过与E2 F形成复合物来调节E2 F活性的E2 F结合蛋白 E2 F又受ElA蛋白的调节，ElA使E2 F/E2 FBP解离 复合物需要ElA的结构域1和2，这两个结构域是 也参与这种癌蛋白的转化功能。 因此 该提案的主要重点是E2 FBP的生物化学表征， 生产针对E2 FBP的特异性抗血清，这将有助于分析 控制的基础。 SV 40 T抗原和HPV E7蛋白 与ElA的结构域1和2具有序列同源性，这两个结构域 癌蛋白也反式激活腺病毒E2启动子，这取决于 E2 F结合位点。 还将分析这两种蛋白质的 控制E2 F/E2 FBP相互作用的能力。 另一个有趣的是 建议分析控制DNA结合的机制 E1 A调节的转录因子E4 F的活性。 具体 将使用以下方法获得试剂，如肽抗血清和cDNA克隆， 肽序列信息。 这些试剂将非常 在E4 F通过磷酸化调节的研究中有价值， 腺病毒E1 A基因产物。 该提案还着重于 鉴定一种细胞激酶，其可能参与 E4 F DNA结合活性的调节。

The long term goal of this proposal is to elucidate the transcription regulatory pathways that are also targets of oncogene action such as the adenovirus ElA. Several oncogene products have been identified. Determination of the biochemical functions of these oncogene products will eventually elucidate the pathways that lead to transformation and tumorigenesis. Evidence is accumulating that the majority of the oncogene products are involved in the control of gene expression. This proposal involves functional analysis Of ElA oncogene products with regard to their effect on the activities on the cellular proteins such as E2F, E4F and E2FBP. E2F and E4F are cellular transcription factors that are involved in the control of the adenovirus early genes. E2FBP is an E2F binding protein that modulates E2F activity by forming a complex with E2F which in turn is regulated by ElA proteins.ElA dissociates E2F/E2FBP complex requiring the domains 1 and 2 of ElA and these two domains are also involved in the transformation function of this oncoprotein. Thus a major focus of this proposal is biochemical characterization of E2FBP and production of specific antisera against E2FBP which will help analyzing the basis of ElA control. The SV40 T antigen and the HPV E7 protein possess sequence homology with domains 1 and 2 of ElA and these two oncoproteins also trans-activate adenovirus E2 promoter depending on the E2F binding site. These two proteins will also be analyzed for their ability to control E2F/E2FBP interaction. The other interest of this proposal is to analyze the mechanism that control the DNA binding activity of the ElA-regulated transcription factor E4F. Specific reagents, like peptide antisera and cDNA clones, will be obtained using the peptide sequence information. These reagents will be extremely valuable in the studies of E4F regulation by phosphorylation as well as by the adenovirus ElA gene products. The proposal also focuses on identification of a cellular kinase that might be involved in the regulation of E4F DNA binding activity.