DE PEDIATRIC COBRE: MECHANISMS OF CELL DEATH IN SPINAL MUSCULAR ATROPHY

DE PEDIATRIC COBRE：脊髓性肌萎缩症中细胞死亡的机制

• 批准号: 7720953
• 负责人: WENLAN WANG
• 金额: $ 14.72万
• 依托单位: ALFRED I. DU PONT HOSP FOR CHILDREN
• 依托单位国家: 美国
• 财政年份: 2008
• 资助国家: 美国
• 起止时间: 2008-08-01 至 2009-07-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7720953
• 关键词: Biological; Biological Models; Camptothecin; Cell Death; Cell Survival; Cessation of life; Childhood; Complex; Computer Retrieval of Information on Scientific Projects Database; Cultured Cells; Cytoprotection; Disease; Fibroblasts; Funding; Genetic; Goals; Grant; Human; Infant; Institution; Mediating; Motor Neurons; Muscular Atrophy; Mutation; Neuromuscular Diseases; PC12 Cells; Pathway interactions; Patients; Play; Prevention; Protein p53; Proteins; RNA Splicing; Reporting; Research; Research Personnel; Resources; Role; Skin; Source; Spinal Muscular Atrophy; Stimulus; TP53 gene; Testing; United States National Institutes of Health; caspase-3; motor neuron degeneration; survival motor neuron gene

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. Spinal muscular atrophy (SMA) is a neuromuscular disease characterized by degeneration of motor neurons and progressive muscle atrophy. The disease is one of the most common genetic causes of infant death. Deletion or mutation(s) of the survival motor neuron gene (SMN1) causes the disease. The SMN protein has been known to function in the assembly of the RNA splicing complex; however, the mechanism(s) by which SMN-deficiency causes cell death in SMA are not clear. Our long-term goal is to understand the mechanism(s) of motor neuron death in SMA and develop a means of prevention. SMN protein has been reported to have some survival-promoting functions in cultured cells. Our studies showed that skin fibroblasts derived from SMA patients are more sensitive to certain death-promoting stimuli than control fibroblasts. We hypothesize that the SMN protein is directly involved in cell survival and that loss of SMN?s survival function results in motor neuron death in SMA. We have used skin fibroblasts derived from SMA patients and PC12 cells as model systems to test this hypothesis. We found that SMA fibroblasts are more prone to camptothecin?induced cell death. Camptothecin treatment results in significant higher caspase-3 activity in SMA fibroblasts, and levels of SMN protein are inversely associated with caspase-3 activity induced by camptothecin. We also demonstrated that transient expression of human SMN in both na¿ve and differentiated PC12 cells decreased camptothecin?activated caspase-3 activity. Upon camptothecin treatments, levels of p53 protein are elevated, suggesting SMN may play its survival function through pathway(s) that are involved in p53. We are currently investigating the effect of SMN on p53 -induced death in PC12 cells. We will further elucidate the role of SMN in motor neuron survival. Finally, we will continue to determine biological pathway(s) of SMN-mediated cell protection.

这个子项目是许多研究子项目中利用 资源由NIH/NCRR资助的中心拨款提供。子项目和 调查员(PI)可能从NIH的另一个来源获得了主要资金， 并因此可以在其他清晰的条目中表示。列出的机构是 该中心不一定是调查人员的机构。 脊髓性肌萎缩症(SMA)是一种以运动神经元变性和进行性肌肉萎缩为特征的神经肌肉疾病。这种疾病是导致婴儿死亡的最常见的遗传原因之一。运动神经元存活基因(SMN1)的缺失或突变(S)会导致这种疾病。已知SMN蛋白在RNA剪接复合体的组装中起作用，然而，SMN缺乏导致SMA细胞死亡的机制(S)尚不清楚。我们的长期目标是了解SMA运动神经元死亡的机制(S)，并开发一种预防方法。据报道，SMN蛋白在培养细胞中具有一定的促存活功能。我们的研究表明，来自SMA患者的皮肤成纤维细胞对某些促死亡刺激比对照成纤维细胞更敏感。我们推测SMN蛋白直接参与细胞存活，SMN？S生存功能丧失导致SMA运动神经元死亡。我们使用来自SMA患者的皮肤成纤维细胞和PC12细胞作为模型系统来验证这一假说。我们发现SMA成纤维细胞更容易发生喜树碱诱导的细胞死亡。喜树碱可诱导SMA成纤维细胞caspase-3活性显著升高，且SMN蛋白水平与喜树碱诱导的caspase-3活性呈负相关。我们还证明，人SMN在NA和分化的PC12细胞中的瞬时表达降低了喜树碱激活的caspase-3的活性。喜树碱治疗后，p53蛋白水平升高，提示SMN可能通过参与P53的通路(S)发挥其生存功能。我们目前正在研究SMN在P53诱导的PC12细胞死亡中的作用。我们将进一步阐明SMN在运动神经元存活中的作用。最后，我们将继续确定SMN介导的细胞保护的生物途径(S)。