FUNCTIONAL ANALYSIS OF DIFFERENTLY METHYLATED H19 GENE

本研究的目的是研究基因组的调控 在小鼠中使用母体表达的H19基因作为印记， 实验系统基因组印记是指 依赖于亲本来源的等位基因。它发生在哺乳动物中， 因此，某些基因的母系和父系拷贝都是 是正常发展所必需的。此外，印记还涉及到 几种人类疾病，以及对印记的理解可能有助于 这些人类疾病的矫正。尽管有几个基因 在老鼠和人类身上都有印记， 父母的身份是不明确的。然而，一个强有力的候选人， 等位基因的差异标记是 CpG二核苷酸。对于H19，父本特异性甲基化序列具有 已经鉴定了H19转录所不需要的。的 这项建议的具体目的是确定父亲的作用 甲基化的H19序列，通过从内源基因座去除该序列 使用同源重组，然后在小鼠中研究结果， 在亲本特异性免疫组织化学中分析来自所述缺失等位基因的H19表达， 方式

The objective of this proposal is to study the regulation of genomic imprinting in mouse using the maternally expressed H19 gene as the experimental system. Genomic imprinting is the differential expression of alleles dependent upon the parental origin. It occurs in mammals and, as a consequence, both a maternal and a paternal copy of certain genes are required for normal development. In addition, imprinting is implicated in several human diseases, and the understanding of imprinting may facilitate the correction of these human diseases. Although several genes have been shown to be imprinted in both mice and humans, the mechanism by which parental identity is assigned is unclear. However, a strong candidate for the differential marking of alleles is methylation of cytosine residues in CpG dinucleotides. For H19, a paternal specific methylated sequence has been identified which is not required for transcription of H19. The specific aim of this proposal is to determine the role of the paternally methylated H19 sequence by removing the sequence from the endogenous locus using homologous recombination and then studying the outcome in mice by analyzing H19 expression from the disrnpted allele in a parental-specific manner.