Mouse Model for Zellweger Syndrome

齐薇格综合症小鼠模型

• 批准号: 6743586
• 负责人: SKAIDRITE K KRISANS
• 金额: $ 4.4万
• 依托单位: SAN DIEGO STATE UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2001
• 资助国家: 美国
• 起止时间: 2001-05-01 至 2005-04-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6743586
• 关键词: brain metabolism; central nervous system disorders; cerebrohepatorenal syndrome; cholesterol; disease /disorder model; endoplasmic reticulum; gene targeting; immunocytochemistry; in situ hybridization; isoprenoid; laboratory mouse; molecular pathology; newborn animals; peroxisome; steroid biosynthesis

DESCRIPTION(adapted from applicant's abstract): Recent studies have indicated that cholesterol is essential for normal brain development and that the central nervous system depends mainly on de novo cholesterol biosynthesis. We have shown that peroxisomes are essential for cholesterol biosynthesis, due to the fact that the entire pathway for the biosynthesis of farnesyl diphosphate (FPP) from mevalonate is exclusively found in peroxisomes. Therefore, peroxisomes must play a critical functional role in this process in the CNS. However, no information is available on the peroxisomal isoprenoid/cholesterol biosynthesis pathway in normal brain or on the compartmentalization of isoprene metabolism in the CNS. An animal model for Zellweger syndrome (i.e., a peroxisomal PEX2 knockout mouse) has been recently developed. These mice provide an important model to study the role of peroxisomal function in the CNS in the pathogenesis of the neurological abnormalities observed in these diseases. In this proposal we address the hypothesis that peroxisomes have a central role in isoprenoid/cholesterol biosynthesis in the CNS and that in PEX2 knockout mice, the isoprenoid/cholesterol biosynthesis in the CNS is significantly altered. To test this hypothesis the following specific aims are proposed: 1) To determine the role of peroxisomes in isoprenoid/cholesterol biosynthesis in normal neonatal mouse brain. The isoprenoid biosynthetic pathway in neonatal mouse brain will be analyzed by subcellular fractionation, activity and immunoblot analysis of the gradient fractions, and immunohistochemistry and in situ hybridization techniques. We will also determine if the relative distribution of peroxisomal and ER contribution to sterol/non-sterol biosynthesis changes during development. 2) To test for defects in lipid composition and cholesterol/dolichol metabolism in PEX2 deficient mice. We will determine how the regulation of cholesterol enzymes and the rate limiting steps in the pathway may be altered by the decompartmentalization of cholesterol synthesis due to the absence of peroxisomes. The studies are designed to ascertain whether there is a basis to implicate cholesterol in some of the neurologic defects observed in the Zellweger mouse. Thus a comparison of isoprenoid/cholesterol metabolism in the PEX2 deficient and normal animals can render insight into the mechanism(s) for the neurological phenotype seen in the knockout mice.

描述（改编自申请人的摘要）：最近的研究表明 该胆固醇对于正常的大脑发育至关重要，并且中央 神经系统主要取决于从头胆固醇生物合成。我们有 表明过氧化物酶体对于胆固醇生物合成至关重要 Farnesyl Diphosphate（FPP）生物合成的整个途径的事实 在过氧化物酶体中仅发现了甲瓦龙酸盐。因此，过氧化物酶体 必须在中枢神经系统中的此过程中起关键的功能作用。但是，不 有关过氧化物酶类异种/胆固醇生物合成的信息 正常大脑或异戊二烯代谢的隔室化的途径 在中枢神经系统中。 Zellweger综合征的动物模型（即过氧化物酶体PEX2 敲除鼠标）最近已开发。这些老鼠提供了重要的 研究过氧化物酶体功能在中枢神经系统中的作用的模型 在这些疾病中观察到的神经系统异常。在此提案中 我们解决了过氧化物酶体在 中枢神经系统中的类异型/胆固醇生物合成，在PEX2基因敲除小鼠中， 中枢神经系统中的类异戊二烯/胆固醇生物合成显着改变。 为了检验该假设，提出了以下特定目标： 1）确定过氧化物酶体在类异戊二烯/胆固醇生物合成中的作用 在正常的新生小鼠大脑中。新生儿中的类异型生物合成途径 小鼠大脑将通过亚细胞分馏，活性和 梯度分数和免疫组织化学的免疫印迹分析以及 原位杂交技术。我们还将确定亲戚是否 过氧化物酶体和ER贡献对固醇/非霉菌的贡献 发育过程中的生物合成变化。 2）测试脂质成分和胆固醇/多利哥代谢中的缺陷 在PEX2缺乏小鼠中。我们将确定胆固醇的调节如何 酶和途径中的速率限制步骤可能会通过 由于没有 过氧化物酶体。 研究旨在确定是否有依据 在Zellweger小鼠中观察到的一些神经系统缺陷中的胆固醇。 因此，比较PEX2缺乏的类异戊二烯/胆固醇代谢 正常动物可以洞悉 敲除小鼠中看到的神经表型。