DEVELOPMENT AND ANALYSIS OF A MODEL MOUSE FOR NONKETOTIC HYPERGLYCINEMIA

非酮症高甘氨酸血症模型小鼠的研制与分析

• 批准号: 08672593
• 负责人: KURE Shigeo
• 金额: $ 1.34万
• 依托单位: TOHOKU UNIVERSITY
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (C)
• 财政年份: 1996
• 资助国家: 日本
• 起止时间: 1996 至 1997
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-08672593/
• 关键词: glycine metabolism; ES cells; transgenic mouse; chromosomal location; CA repeat marker; 非ケトーシス型高グリシン血症; ノックアウトマウス; NMDA受容体; in sity hybridization; 相同組み換え

Nonketotic hyperglycinemia (NKH) is an inherited metabolic disease, characterized by marked elevation of the glycine level in body fluid and severe neurological abnormalities. NKH is caused by defect in the mitochondrial glycine cleavage system (GCS). The GCS consists of the four protein components referred to as P-, T-, H-, and L-proteins. In the central nervus system (CNS) the overall activity of the GCS was high in forebrain and cerebellum, whereas it was hardly detected in spinal cord and brain stem. In line with this observation the glycine content was high in spinal cord and cerebrum, but low in cerebral cortex and cerebellum. To elucidate the molecular pathogenesis of NKH we examines the GCS in mouse brain by using a transgenic technique. We mapped mouse P-protein gene was on chromosome 19C and isolated a intragenic CA repeat marker. We generated a transgenic (Tg) mouse overxpressing the human P-protein cDNA which was under control of potent CAG promoter. The Tg mouse expressed a large amount of human P-protein mRNA and the overall GCS activities in various regions of mouse brain. The glycine content in the spinal cord of the Tg mouse was markedly reduced compared with wild type mouse. These data suggested that the overall activities of the GCS in each region of CNS was closely correlated with the expression level of the P-protein, and the GCS plays a pivotal role in regulation of the glycine content in various regions of CNS.

非酮症高甘氨酸血症（NKH）是一种遗传性代谢性疾病，其特征是体液中甘氨酸水平显着升高和严重的神经系统异常。 NKH 是由线粒体甘氨酸裂解系统 (GCS) 缺陷引起的。 GCS 由称为 P、T、H 和 L 蛋白的四种蛋白质成分组成。在中枢神经系统（CNS）中，前脑和小脑中GCS的总体活性较高，而在脊髓和脑干中几乎检测不到。与这一观察结果一致，脊髓和大脑中的甘氨酸含量较高，但大脑皮层和小脑中的甘氨酸含量较低。为了阐明 NKH 的分子发病机制，我们使用转基因技术检查了小鼠大脑中的 GCS。我们将小鼠 P 蛋白基因定位在 19C 号染色体上，并分离出基因内 CA 重复标记。我们生成了一只过表达人类 P 蛋白 cDNA 的转基因 (Tg) 小鼠，该小鼠受强效 CAG 启动子的控制。 Tg小鼠在小鼠大脑的各个区域表达大量的人类P蛋白mRNA和总体GCS活性。与野生型小鼠相比，Tg小鼠脊髓中的甘氨酸含量显着降低。这些数据表明，CNS各区域GCS的整体活性与P蛋白的表达水平密切相关，GCS在CNS各区域甘氨酸含量的调节中发挥着关键作用。