DE PEDIATRIC COBRE: MOLECULAR MECHANISMS IN PELIZAEUS MERZBACHER DISEASE

DE PEDIATRIC COBRE：Pelizaeus Merzbacher 病的分子机制

• 批准号: 7382172
• 负责人: Grace M. Hobson
• 金额: $ 15.26万
• 依托单位: ALFRED I. DU PONT HOSP FOR CHILDREN
• 依托单位国家: 美国
• 财政年份: 2006
• 资助国家: 美国
• 起止时间: 2006-08-01 至 2007-07-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7382172
• 关键词: DE; PEDIATRIC; COBRE; MOLECULAR; MECHANISMS

This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. Pelizaeus-Merzbacher disease (PMD), an X-linked leukodystrophy, is caused by defects of the proteolipid protein 1 gene (PLP1) that encodes the major CNS myelin protein. Approximately 60% of families have a genomic duplication that includes the PLP1 gene, and 15-20% of families have PLP1 point mutations. Studies in mice have shown that an increased dosage of PLP1 can account for disease pathogenesis. Further, studies have shown that mutations in noncoding regions can alter PLP1 expression levels or the ratio of the alternatively spliced forms PLP1 and DM20. Our long-term objective is to understand the molecular mechanisms involved in generating the PMD phenotype so rational treatments and improved diagnostic techniques can be developed. In the first aim, results on location, size, structure and sequence at the junctions of PMD duplications support the hypothesis that most are caused by a novel coupled homologous and nonhomologous mechanism. We will continue a combined cytogenetic, molecular, and in silico approach to refine our understanding of the mechanism. In the second aim, the hypothesis that the duplication structure affects expression of PLP1 is being tested by engineering different duplications into ES cell lines and analyzing the structural effects on gene expression before and after differentiation into oligodendrocytes. In the third aim, the hypothesis that some PMD mutations dysregulate splicing of PLP1 is being tested by using gene transfer and RNA-protein binding assays to investigate cis-acting elements and trans-acting factors involved in PLP1/DM20 alternative splicing. We have determined that exon and intron splicing enhancers and the relative strength of the PLP1 and DM20 donor splice sites play an important role in PLP1 alternative splicing. The results of these studies have greatest impact potential through their generalizability to other genomic and splicing diseases, which have only recently been recognized as important types of genetic disease.

该子项目是利用NIH/NCRR资助的中心赠款提供的资源的许多研究子项目之一。子项目和研究者（PI）可能从另一个NIH来源获得主要资金，因此可以在其他CRISP条目中表示。所列机构为中心，不一定是研究者所在机构。Pelizaeus-Merzbacher病（PMD）是一种X连锁脑白质营养不良，由编码主要CNS髓鞘蛋白的蛋白脂质蛋白1基因（PLP1）缺陷引起。大约60%的家族具有包括PLP1基因的基因组重复，并且15 - 20%的家族具有PLP1点突变。对小鼠的研究表明，PLP1剂量的增加可以解释疾病的发病机制。此外，研究表明，非编码区的突变可以改变PLP1的表达水平或可变剪接形式PLP1和DM20的比例。我们的长期目标是了解参与产生PMD表型的分子机制，以便开发合理的治疗方法和改进的诊断技术。在第一个目标中，PMD重复的位置，大小，结构和序列的交界处的结果支持的假设，大多数是由一个新的耦合同源和非同源机制。我们将继续采用细胞遗传学、分子生物学和计算机模拟相结合的方法来完善我们对该机制的理解。在第二个目标中，重复结构影响PLP1表达的假设正在通过将不同的重复结构工程化到ES细胞系中并分析在分化成少突胶质细胞之前和之后对基因表达的结构影响来测试。在第三个目标中，一些PMD突变失调PLP1剪接的假设正在测试通过使用基因转移和RNA-蛋白质结合试验，以调查顺式作用元件和反式作用因子参与PLP1/DM20选择性剪接。我们已经确定外显子和内含子剪接增强子以及PLP1和DM20供体剪接位点的相对强度在PLP1选择性剪接中起重要作用。这些研究的结果具有最大的影响潜力，因为它们可以推广到其他基因组和剪接疾病，这些疾病最近才被认为是重要的遗传疾病类型。