STRUCTURE AND FUNCTION OF CTCF

CTCF的结构和功能

• 批准号: 2712744
• 负责人: GALINA N FILIPPOVA
• 金额: $ 38.8万
• 依托单位: FRED HUTCHINSON CANCER RESEARCH CENTER
• 依托单位国家: 美国
• 财政年份: 1996
• 资助国家: 美国
• 起止时间: 1996-06-05 至 2000-03-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/2712744
• 关键词: Wilms' tumor; breast neoplasms; genetic promoter element; genetically modified animals; laboratory mouse; neoplastic growth; nucleic acid sequence; oncoproteins; protein structure function; protooncogene; regulatory gene; tissue /cell culture; tumor suppressor genes

DESCRIPTION: (adapted from the investigator's abstract) The proto-oncogene c-myc is implicated in the regulation of such fundamental cellular processes as growth, differentiation and programmed death. De-regulation of c-myc expression is associated with neoplasia in humans and experimental animals. Relatively little is known about genes which regulate c-myc expression. Considering the apparent role of myc in molecular biology of cancer, it is reasonable to assume that critical myc regulators could in turn be proteins of major biological importance like oncogenes and tumor suppressor genes. The general goal of this proposal is to obtain an understanding of the molecular biology of a novel candidate tumor suppressor gene, Dr. Lobanenkov have discovered, called CTCF, which encodes an exceptionally highly conserved 11-Zn-finger transcriptional repressor specifically binding to several variant DNA sequences in the promoter-proximal regions of the c-myc proto-oncogene of different vertebrate species by utilizing different combinations of individual fingers. Several additional lines of evidence suggest that CTCF appears to be an important regulatory gene: (1) It is exceptionally highly conserved transcriptional repressor, (2) Its binding to diverged promoter sequences of vertebrate c-myc genes represses their transcription; (3) CTCF locus is rearranged in some F-MuLV-induced mouse erythroleukemia cell lines; (4) CTCF gene is localized at the locus of chromosome abnormalities frequently found in several human cancers. It is rearranged in some breast cancer cell lines, primary breast tumors and in certain Wilms' tumors. To investigate the mechanism of CTCF activity and to gain insight into CTCF's role in neoplastic change and normal development this project will: (1) Characterize structure-function of the CTCF polypeptide and determine whether specific binding of CTCF to the human c-myc promoter is involved in regulation of polymerase II initiation and/or processivity; (2) Characterize alterations of CTCF gene in certain breast cancer tumors and cell lines and in some Wilms' tumors which have already found to have an aberrant structure of the CTCF locus. Expand mutational analysis of CTCF to a larger group of breast tumors to characterize in detail an association of CTCF mutations and breast tumorigenesis. Determine whether CTCF has aberrant structure and/or expression in a number of other cancers associated with abnormalities of chromosome 16q22, the locus of human CTCF; (3) Define structure of the altered CTCF gene locus and sequence of abnormal CTCF-containing mRNA(s) which Dr. Lobanenkov have found in some Friend leukemia virus (F-MuLV)-induced cell lines; (4) Characterize the consequence of deletion of CTCF in transgenic mice and the pattern of CTCF expresion in normal development; (5) Determine additional CTCF-binding DNA sequences and identify other CTCF-target genes besides c-myc.

描述：（改编自研究者摘要）原癌基因 c-myc与这些基本细胞过程的调节有关 生长分化和程序性死亡 c-myc失调 表达与人类和实验动物中的瘤形成有关。 对调控c-myc表达的基因知之甚少。 考虑到myc在癌症分子生物学中的明显作用， 假设关键的myc调节子反过来可能是蛋白质是合理的 具有重要生物学意义的基因，如癌基因和肿瘤抑制基因。 本提案的总体目标是了解 一种新的候选肿瘤抑制基因的分子生物学，Lobanenkov博士 发现了一种叫做CTCF的基因， 保守的11-锌指转录抑制子特异性结合 c-myc启动子近端区域的几个变异DNA序列 不同脊椎动物物种的原癌基因 单个手指的组合。 几条额外的证据 提示CTCF可能是一个重要的调控基因：（1）它是 异常高度保守的转录抑制因子，（2）其与 脊椎动物c-myc基因的趋异启动子序列抑制它们的 （3）F-MuLV诱导的小鼠CTCF基因座重排 （4）CTCF基因定位于红白血病细胞系的 染色体异常经常在几种人类癌症中发现。 是 在一些乳腺癌细胞系、原发性乳腺肿瘤和乳腺癌细胞中， 某些维尔姆斯瘤 研究CTCF活性的机制， CTCF在肿瘤变化和正常发展中的作用该项目将： (1)表征CTCF多肽的结构-功能并确定 CTCF与人c-myc启动子的特异性结合是否涉及 聚合酶II起始和/或持续合成能力的调节;（2）表征 某些乳腺癌肿瘤和细胞系中CTCF基因的改变， 在一些已经发现具有异常结构的肾母细胞瘤中， CTCF基因座。 将CTCF的突变分析扩展到更大的组， 乳腺肿瘤，以详细描述CTCF突变和 乳腺肿瘤发生 确定CTCF是否具有异常结构和/或 在许多其他癌症中的表达与 染色体16 q22，人类CTCF的位点;（3）确定CTCF的结构， 改变的CTCF基因座和含有异常CTCF的mRNA的序列 Lobanenkov博士在一些Friend白血病病毒中发现的 （F-MuLV）-诱导的细胞系;（4）表征缺失F-MuLV的结果。 CTCF在转基因小鼠中的表达及正常小鼠CTCF的表达模式 （5）确定额外的CTCF结合DNA序列， 鉴定除了c-myc之外的其它CTCF靶基因。