CLONING AND CHARACTERIZING NEW IMPRINTED GENES

描述：（改编自PI摘要）本项目涉及 基因组印记的功能和潜在的调控机制。 该项目的目标包括：1）识别额外的小鼠 印迹基因，以建立在比较工作的基础上， 人类基因组 使用限制性标志基因组扫描（RLGS）方法， 鉴定了显示等位基因特异性甲基化的候选基因座; 印迹基因的共同特点，导致新的印迹克隆 基因. 现在计划克隆另外11个候选基因座， 初步表征并大规模鉴定相邻基因 其中一个的基因克隆 2)一个新的详细描述 在小鼠9号染色体上识别出的印记区域，包括父本 表达了GRF 1（鸟嘌呤核苷酸交换因子）基因。 Grf 1是老鼠 同源于酵母CDC 25基因，其充当Ras激活剂，因此 在细胞周期调控中起重要作用。 的基因组结构 将分析基因组克隆的500 kbp重叠群内的Grf 1基因。 这些实验将包括外显子-内含子的表征 Grf 1结构，其他等位基因特异性甲基化的鉴定 位点和外显子捕获实验来鉴定新的编码序列。 第三章 对不同可变剪接体的表达进行了详细的研究， Grf 1转录本的形式，包括鉴定和分析 启动子的最大，父系表达的Grf 1转录。

DESCRIPTION: (adapted from the PI's abstract) This project addresses the function of genomic imprinting and the underlying regulatory mechanisms. The goals of the project include: 1) Identification of additional mouse imprinted genes in order to establish the basis for comparative work in the human genome. Using the Restriction Landmark Genome Scanning (RLGS) method, candidate loci were identified which show allele-specific methylation; a common feature of imprinted genes that led to the cloning of novel imprinted genes. It is now planned to clone 11 additional candidate loci for preliminary characterization and to identify the adjacent gene in large genomic clones for one of them. 2) A detailed characterization of the newly identified imprinted region on mouse chromosome 9 including the paternally expressed Grf1 (guanine nucleotide exchange factor) gene. Grf1 is the mouse homologue to the yeast CDC25 gene which acts as a Ras activator and thus plays an important role in cell cycle regulation. The genomic structure of the Grf1 gene within a 500 kbp contig of genomic clones will be analyzed. These experiments will include the characterization of the exon-intron structure of Grf1, identification of additional allele-specific methylation sites and exon-trapping experiments to identify novel coding sequences. 3) A detailed study on the expression of the different alternatively spliced forms of Grf1 transcripts, including the identification and analysis of the promoter for the largest, paternally expressed Grf1 transcript.