IDENTIFYING AFR2--GENE REGULATOR IN LIVER PATHOLOGY

描述：甲胎蛋白(AFP)基因是一种肿瘤胎儿抗原， 在发育中的胎儿中表达，在病理条件下 成人的再生和肿瘤发生。甲胎蛋白基因水平 小鼠肝再生过程中的表达受一种基因调控 常染色体非连锁基因座，Afr2。近交系C57B1/6小鼠表达8至10倍 肝再生过程中甲胎蛋白低于野生型C3H/He小鼠。较低的AFP 再生肝中的表达可能反映了其他调节过程，如 C57B1/6小鼠比C3H/He小鼠对肝癌的易感性较低 老鼠。从这些和其他遗传学研究来看，Afr2基因似乎 是多态的。由于Afr2调节AFP的表达，因此使用这些不同的 小鼠品系为识别调控基因提供了独特的机会 甲胎蛋白在肝再生过程中的表达。使用来自鼠标的信息 基因组计划，在第一系列实验中，Afr2基因将被 基因图谱。该基因座的克隆DNA将从一个 酵母人工染色体文库。转录的序列将被分离出来 通过外显子捕获和/或cDNA的方向选择。两个标准将是 用来确定转录的序列以及 先前定位到该基因座的基因是Afr2：与Afr2的遗传连锁 肝再生过程中的基因和表达。在第二个系列中 实验中，我们将制备全长的Afr2基因克隆，并将其导入 进入原代肝细胞培养系统，并测试其能力 调节甲胎蛋白基因表达。分析了两个已知的活动 将比较Afr2等位基因。鉴定并分离出一个克隆的 Afr2基因将为研究二者之间的关系提供工具。 发育性生长、受控生长和不受控制的致瘤生长 在肝脏里。

DESCRIPTION: The alpha-fetoprotein (AFP) gene is an onco-fetal antigen, expressed in the developing fetus and under the pathological conditions of regeneration and tumorigenesis in the adult. The level of AFP gene expression during liver regeneration in mice is regulated by a genetically unlinked autosomal locus, Afr2. Inbred C57B1/6 mice express 8 to 10 fold less AFP during liver regeneration than wild type C3H/He mice. Lower AFP expression in regenerating liver may reflect other regulatory processes, as C57B1/6 mice are less susceptible to liver carcinogenesis than are C3H/He mice. From these and other genetic studies, it appears that the Afr2 gene is polymorphic. Since Afr2 regulates AFP expression, use of these different mouse strains provides a unique opportunity to identify a gene regulating AFP expression during liver regeneration. Using information from the Mouse Genome Project, in the first series of experiments, the Afr2 gene will be genetically mapped. Cloned DNA of this locus will be identified from a Yeast Artificial Chromosome library. Transcribed sequences will be isolated by exon-trapping and/or direction selection of cDNAs. Two criteria will be used to determine the likelihood that the transcribed sequences, as well as genes previously mapped to the locus, are Afr2: genetic linkage to the Afr2 gene and expression during liver regeneration. In the second series of experiments, a full length Afr2 cDNA clone will be prepared, transfected into a primary hepatocyte culture system, and tested for its ability to regulate AFP gene expression. Analysis of the activity of the two known Afr2 alleles will be compared. Identifying and isolating a clone of the Afr2 gene will provide a tool to study the relationships between developmental growth, controlled growth, and uncontrolled tumorigenic growth in the liver.