Drosophila and mouse models of PNPO deficiency

PNPO 缺乏症的果蝇和小鼠模型

基本信息

批准号：
10307547
负责人：
Xiaoxi Zhuang
金额：
$ 41.81万
依托单位：
UNIVERSITY OF CHICAGO
依托单位国家：
美国
项目类别：
财政年份：
2019
资助国家：
美国
起止时间：
2019-12-01 至 2024-11-30
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/10307547
关键词：
Adult Affect Alleles Anatomy Animal Model Antiepileptic Agents Biochemical Biological Assay Birth Blood - brain barrier anatomy Brain Chemicals Child Coenzymes Data Defect Development Developmental Delay Disorders Diet Dominant-Negative Mutation Dopamine Drosophila genus Environment Environmental Risk Factor Enzymes Epilepsy Essential Genes Genes Genetic Histamine Homologous Gene Human International Knock-in Knock-in Mouse Knock-out Larva Lead Liver Cirrhosis Longevity Malnutrition Modeling Mus Mutation Neonatal Neurons Neurotransmitters Newborn Infant Other Genetics Patients Phenotype Point Mutation Proteins Pupa Pyridoxal Phosphate Pyridoxamine Pyridoxine 5 Phosphate Oxidase Reporting Role Seizures Serotonin Severities System Testing Transgenic Organisms Treatment outcome Vitamin B 6 Deficiency Vitamin B6 cell type cofactor cost effective dietary early onset epileptic encephalopathies fly functional disability gamma-Aminobutyric Acid gene interaction genetic manipulation human disease in vivo knock-down loss of function mutation mouse model mutant neural circuit neurochemistry neuromechanism

项目摘要

Abstract Pyridoxine 5'-phosphate oxidase (PNPO) is a rate-limiting enzyme in converting inactive forms of Vitamin B6 (VB6) in diet, including pyridoxine and pyridoxamine, to the only active form, pyridoxal 5'-phosphate (PLP). PLP is a cofactor required for the syntheses of dopamine, serotonin and GABA in the brain. In humans, PNPO deficiency is known to cause neonatal epileptic encephalopathy (NEE). Mutations in PNPO have been increasingly reported in NEE patients. Recent studies also identify PNPO as a contributor to early-onset epilepsies and one of the16 epilepsy genes involved in the common epilepsies. However, due to the lack of animal models, we know little about the developmental or adult functional impact of PNPO deficiency at systems, circuit or cellular level (e.g. involvement of GABA, dopamine or serotonin synthesis) under in vivo conditions. We know little about how mild PNPO deficiency interacts with other genetic defects or environmental factors (e.g. VB6 in diet) to cause seizures or other conditions. We have identified the Drosophila homolog of PNPO and identified a Drosophila mutant (sgll95 flies) with partial PNPO deficiency. Due to low PNPO activity, they are sensitive to dietary VB6 deficiency. We have since generated global knock-down as well as knock-in models in which the endogenous wild-type (WT) fly PNPO was replaced by human mutant PNPO found in patients. Viability during development, lifespan and seizure phenotype of these flies depend on the specific genetic manipulation as well as availability of VB6 in diet. We have also found that PNPO deficiency exacerbated other epileptic mutant alleles in flies with significant synergistic interactions. In Aim 1, we will define specific developmental stages in fly models in which PNPO deficiency leads to lethality and seizures. In Aim 2, we will define brain specific cell types involved in PNPO- deficiency-induced lethality and seizures in fly and mouse models. We will test gene-gene interactions (e.g., PNPO and other known epilepsy genes). In Aim 3, we will generate and characterize fly and mouse models that carry human PNPO mutations. 1

抽象的吡哆醇 5'-磷酸氧化酶 (PNPO) 是转化非活性维生素形式的限速酶饮食中的 B6 (VB6)，包括吡哆醇和吡哆胺，其唯一的活性形式是吡哆醛 5'-磷酸 (PLP)。 PLP 是大脑中合成多巴胺、血清素和 GABA 所需的辅助因子。在人类中，PNPO 缺乏已知会导致新生儿癫痫性脑病 (NEE)。突变在 PNPO 在 NEE 患者中的报道越来越多。最近的研究还确定 PNPO 是早发性癫痫和常见癫痫涉及的 16 个癫痫基因之一。然而，由于由于缺乏动物模型，我们对 PNPO 对发育或成年功能的影响知之甚少系统、回路或细胞水平的缺陷（例如，GABA、多巴胺或血清素合成的参与）在体内条件下。我们对轻度 PNPO 缺乏如何与其他遗传缺陷或其他遗传缺陷相互作用知之甚少。环境因素（例如饮食中的 VB6）导致癫痫发作或其他病症。我们已经鉴定了 PNPO 的果蝇同源物，并鉴定了果蝇突变体（sgll95 果蝇）部分PNPO缺乏。由于 PNPO 活性较低，它们对饮食中 VB6 缺乏很敏感。我们从那时起生成了全局敲低和敲入模型，其中内源野生型 (WT) 蝇 PNPO 被患者体内发现的人类突变体 PNPO 所取代。发育、寿命和癫痫发作期间的活力这些果蝇的表型取决于特定的基因操作以及饮食中 VB6 的可用性。我们还发现 PNPO 缺乏加剧了果蝇中的其他癫痫突变等位基因，并具有显着的协同相互作用。在目标 1 中，我们将定义飞行模型的特定发育阶段，其中 PNPO 缺乏会导致死亡和癫痫发作。在目标 2 中，我们将定义参与 PNPO 的大脑特定细胞类型- 果蝇和小鼠模型中缺乏引起的死亡和癫痫发作。我们将测试基因与基因的相互作用（例如， PNPO 和其他已知的癫痫基因）。在目标 3 中，我们将生成并表征果蝇和小鼠模型携带人类 PNPO 突变。 1