CONTROL OF C-MYC TRANSCRIPTION IN AGGRESSIVE LYMPHOMAS

我建议在分子水平上研究c-myc的激活机制， 在伯基特淋巴瘤和转化淋巴瘤中的水平与t（8;14） 易位 目标是更好地了解 B细胞恶性转化的机制。 A. 转录调控的分子机制 c-myc基因在B细胞中的表达。 将使用体内足迹法和体外蛋白质-DNA结合研究 定位正常B中对c-myc表达重要的调控区域 细胞和不含t（8;14）易位的B细胞系中。 体内结合的蛋白质的身份将通过免疫组织化学测定。 UV交联和免疫沉淀技术， 杂交分析 将对研究中心进行功能评估， 在B细胞系中进行瞬时转染实验。 B。 转录调控的分子机制 伯基特淋巴瘤中的c-myc基因。 条件已经优化 从正常的c-myc基因中分离易位的c-myc基因， 几种伯基特氏细胞系 转录结合的差异 两个等位基因之间的因素已经发现，这些研究将是 持续期间内的 鉴定和表征的蛋白质， 体内结合将如A中所述测定。 的甲基化状态 每个人都将被比较。 C. 转录调控的分子机制 c-myc和bcl-2基因在恶性转化淋巴瘤和低度恶性转化淋巴瘤中的表达 同行 c-myc和bcl-2的失调， 免疫球蛋白基因座将如B中所述进行研究。 D. 在调控基因中鉴定的突变对c-myc表达的影响 地区 任何突变对调节蛋白结合的影响 将通过体内和体外研究来研究蛋白质。 E. 免疫球蛋白基因座在c-myc表达激活中的作用。 复制c-myc易位的模型构建将是 构建并用于定义免疫球蛋白的重要区域 基因座 这项提案的成功完成将是第一个 例如，参与转录的分子机制 通过易位激活癌基因是已知的。 转录 将确定c-myc激活所需的因素 以及免疫球蛋白基因座上负责这个的区域 将被定义。

I propose to study the mechanism of activation of c-myc at a molecular level in both Burkitt's lymphoma and transformed lymphomas with the t(8;14) translocation. The goal is to reach a better understanding of the mechanisms of malignant transformation of B cells. A. Identification of the molecular mechanisms of transcriptional control of th c-myc gene in B cells. In vivo footprinting and in vitro protein-DNA binding studies will be used to locate regulatory regions important for c-myc expression in normal B cells and in B cell lines that do not contain the t(8;14) translocation. The identity of the proteins that bind in vivo will be determined by a technique of UV crosslinking and immunoprecipitation followed by hybridization analysis. Functional assessment of the sites will be performed with transient transfection experiments in B cell lines. B. Identification of the molecular mechanisms of transcriptional control of the c-myc gene in Burkitt's lymphomas. Conditions have been optimized for the separation of the translocated from the normal c-myc gene in several Burkitt's cell lines. Differences in the binding of transcription factors between the two alleles have been found and these studies will be continued. The identification and characterization of the proteins that bind in vivo will be determined as described in A. The methylation status of each allele will be compared. C. Identification of the molecular mechanisms of transcriptional control of the c-myc and bcl-2 genes in transformed lymphomas and their low grade counterparts. The deregulation of both c-myc and bcl-2 by the immunoglobulin locus will be studied as outlined in B. D. Effect on c-myc expression of mutations identified in the regulatory regions. The effects of any mutations ont he binding of regulatory proteins will be investigated by in vivo and in vitro studies. E. Role of the immunoglobulin locus in the activation of c-myc expression. Model constructs which reproduce the c-myc translocations will be constructed and used to define the important regions of the immunoglobulin locus. The successful completion of this proposal will represent the first instance where the molecular mechanisms involved in the transcriptional activation of an oncogene by translocation are known. The transcription factors that are required for the activation of c-myc will be identified and the regions of the immunoglobulin locus which are responsible for this will be defined.