Molecular Genetical Analysis of New Cause for Congenital Lactic Acidemia

先天性乳酸血症新病因的分子遗传学分析

• 批准号: 12670754
• 负责人: ITO Michinori
• 金额: $ 2.24万
• 依托单位: The University of Tokushima
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (C)
• 财政年份: 2000
• 资助国家: 日本
• 起止时间: 2000 至 2001
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-12670754/
• 关键词: congenital lactic acidemia; pyruvate dehydrogenase; pyruvate dehydrogenase phosphatase; cDNA; cloning; mutation; pyruvate dehydrogenase phosphatasedeficiency

A deficiency of pyruvate dehydrogenase phosphatase (PDPase) has been suggested as a possible cause of congenital lactic acidemia and Leigh's disease due to a defect of activation of pyruvate dehydrogenase complex (PDHC). However, as yet, the molecular genetical analysis of PDPase in these patients has not been performed. In this study, we isolated two cDNAs for human catalytic subunits of PDPase (PDPcl and PDPc2) and detected a mutation in a patient with a defect of activation of PDHC. Human cDNA for PDPc1 and PDPc2 were highly homologous in nucleotide and protein levels to the previously reported rat PDPc1 and PDPc2, respectively. In addition, genes of PDPc1 and PDPc2 were mapped in chromosome 8, in the region q22-23, and in chromosome 3, in the region q27-28, respectively. With the nucleotide sequence determination, A716T (D239V) in cDNA for PDPc2 was detected in a patient with congenital lactic acidemia due to a defect of activation of PDHC. This amino acid was conserved in human and previously reported PDPc1 and PDPc2. These results suggest that this mutation is the primary defect of activation of PDHC in this patient.

由于丙酮酸脱氢酶复合物（PDHC）激活缺陷，丙酮酸脱氢酶磷酸酶（PDPase）缺乏被认为是先天性乳酸血症和利氏病的可能原因。然而，迄今为止，尚未对这些患者进行 PDPase 的分子遗传学分析。在这项研究中，我们分离了人类 PDPase 催化亚基的两个 cDNA（PDPcl 和 PDPc2），并在一名患有 PDHC 激活缺陷的患者中检测到了突变。 PDPc1 和 PDPc2 的人类 cDNA 在核苷酸和蛋白质水平上分别与先前报道的大鼠 PDPc1 和 PDPc2 高度同源。此外，PDPc1和PDPc2的基因分别定位在8号染色体的q22-23区域和3号染色体的q27-28区域。通过核苷酸序列测定，在由于PDHC激活缺陷而患有先天性乳酸血症的患者中检测到PDPc2的cDNA中的A716T（D239V）。该氨基酸在人类中是保守的，之前报道过 PDPc1 和 PDPc2。这些结果表明该突变是该患者 PDHC 激活的主要缺陷。