A novel role for p53 in congenital disorders of glycosylation

p53 在先天性糖基化疾病中的新作用

• 批准号: 8911832
• 负责人: Jaime C Chu
• 金额: $ 15.09万
• 依托单位: ICAHN SCHOOL OF MEDICINE AT MOUNT SINAI
• 依托单位国家: 美国
• 财政年份: 2013
• 资助国家: 美国
• 起止时间: 2013-09-13 至 2016-07-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8911832
• 关键词: Affect; Animal Model; Apoptosis; Biochemical; Bypass; Cell Death; Cells; Child; Cirrhosis; Congenital Disorders; Data; Defect; Disease; Embryo; Eye; Fatty Liver; Fibroblasts; Fibrosis; Fructose; Functional disorder; Gastrointestinal Diseases; Gene Targeting; Genes; Genetic; Glycoproteins; Goals; Head; Health; Hepatocyte; Human; In Transferrin; Knock-in Mouse; Knowledge; Lead; Link; Liver; Liver diseases; Mannose; Mannose-6-Phosphate Isomerase; Mass Spectrum Analysis; Measures; Mediating; Mendelian disorder; Metabolic; Metabolic Pathway; Metabolism; Minor; Modeling; Molecular; Morbidity - disease rate; Mus; Mutation; Noxae; Oncogene Deregulation; Oral; Pathology; Patients; Pattern; Phenotype; Protein Glycosylation; Protein p53; Proteins; Puma; Research; Residual state; Role; Shapes; Supplementation; Symptoms; System; Systemic disease; Technology; Testing; Tissues; Zebrafish; base; disease phenotype; embryonic stem cell; enzyme activity; gastrointestinal; glycosylation; hexokinase; improved; insight; knock-down; link protein; lipooligosaccharide; mannose 6 phosphate; mortality; mutant; non-alcoholic fatty liver; novel; pediatric patients; response; targeted treatment; transcriptome sequencing

DESCRIPTION (provided by Candidate): Children with the rare congenital disorders of glycosylation (CDG) have a mutation in one of the many genes required for N-linked protein glycosylation and of 38 distinct subtypes, 37 have no treatment options. Mutation of mannose-6-phosphate isomerase (MPI) causes the "gastrointestinal type" of CDG. It is not understood how defective synthesis of the lipid-linked oligosaccharide (LLO) in CDG patients results in multi-systemic abnormalities and few CDG animal models exist. zebrafish provide a powerful vertebrate system to study monogenic disorders with their high genetic conservation to humans, and morpholinos offer rapid and efficient gene knockdown. I used morpholino technology to establish mpi morphants with less than 15% residual Mpi enzyme activity. They develop defects in the head, eye, gut, liver, and body shape with increased cell death in affected tissues. MPI-CDG is the only CDG with a known treatment: oral mannose increases flux through hexokinase and a minor complementary metabolic pathway that produces mannose-6-phosphate and normalizes protein glycosylation, relieving most symptoms. Similarly, both the morphologic and cell death phenotype in mpi morphants are almost completely rescued by mannose supplementation. My preliminary data in a novel zebrafish model of MPI-CDG implicate activation of the tumor suppressor, p53, in CDG pathology. Our objective is to determine whether the well known tumor suppressor, p53, has a novel role in the mechanism of disease in MPI-CDG. Our central hypothesis is that p53 is responsible for disease in MPI-CDG and will determine the mechanism by which p53 affects either metabolic alterations in glycosylation or apoptosis. Specific Aims: 1: Establish the relationship between p53 activation, mannose metabolism, and Mpi deficiency. 2: Determine whether MPI-CDG is a result of abnormal LLO or glycoprotein formation. 3: Determine the contribution of p53-mediated apoptosis to the mpi morphant phenotype. My long-term goal is to understand the molecular basis of CDG with a focus on the associated gastrointestinal disorders. The underlying genetic defect in CDG is simple and well understood. I will then apply this knowledge to more common causes of these same diseases in pediatric patients, as non-alcoholic fatty liver disease, fibrosis, and cirrhosis are all associated with defects in protein glycosylation.

描述（由候选人提供）：患有罕见先天性糖基化障碍 (CDG) 的儿童在 N 联蛋白糖基化所需的众多基因之一中存在突变，并且有 38 种不同的亚型，其中 37 种儿童没有治疗选择。 6-磷酸甘露糖异构酶（MPI）突变导致“胃肠型”CDG。目前尚不清楚 CDG 患者中脂质连接寡糖 (LLO) 的合成缺陷如何导致多系统异常，并且很少存在 CDG 动物模型。斑马鱼为研究单基因疾病提供了强大的脊椎动物系统，其对人类具有高度的遗传保守性，而吗啡啉则提供快速有效的基因敲除。我使用吗啉代技术建立了残留 Mpi 酶活性低于 15% 的 mpi morphant。它们的头部、眼睛、肠道、肝脏和身体形状出现缺陷，受影响组织的细胞死亡增加。 MPI-CDG 是唯一一种具有已知治疗方法的 CDG：口服甘露糖可增加通过己糖激酶的流量，以及产生 6-磷酸甘露糖并使蛋白质糖基化正常化的次要补充代谢途径，从而缓解大多数症状。同样，补充甘露糖几乎可以完全挽救 mpi 形态的形态和细胞死亡表型。我在新型 MPI-CDG 斑马鱼模型中的初步数据表明 CDG 病理学中肿瘤抑制因子 p53 的激活。我们的目标是确定众所周知的肿瘤抑制因子 p53 是否在 MPI-CDG 疾病机制中具有新作用。我们的中心假设是 p53 与 MPI-CDG 疾病有关，并将确定 p53 影响糖基化代谢改变或细胞凋亡的机制。具体目标： 1：建立 p53 激活、甘露糖代谢和 Mpi 缺乏之间的关系。 2：确定 MPI-CDG 是否是异常 LLO 或糖蛋白形成的结果。图3：确定p53介导的细胞凋亡对mpi morphant表型的贡献。我的长期目标是了解 CDG 的分子基础，重点关注相关的胃肠道疾病。 CDG 的潜在遗传缺陷很简单且易于理解。然后，我将把这些知识应用于儿科患者中这些相同疾病的更常见原因，因为非酒精性脂肪肝病、纤维化和肝硬化都与蛋白质糖基化缺陷有关。