Respiration and growth defects in transmitochondrial cell lines carrying the 11778 mutation associated with Leber's hereditary optic neuropathy
Respiration and growth defects in transmitochondrial cell lines carrying the 11778 mutation associated with Leber's hereditary optic neuropathy
复制标题
DOI：
10.1074/jbc.271.22.13155
复制
发表时间：
1996-05-31
影响因子：
4.8
通讯作者：
Chomyn, A
中科院分区：
文献类型：
--
作者：
Hofhaus, G;Johns, DR;Chomyn, A
来自两个遗传上不相关的携带导致Leber遗传性视神经病变的11778位突变的患者的线粒体DNA已经与线粒体一起转移到人类无mtDNA的rho（0）206细胞中。如在由此获得的几个线粒体细胞系中所分析的，在呼吸链NADH脱氢酶（ND）的编码亚基ND 4的基因中的突变不影响ND 4的合成、大小或稳定性，也不影响其掺入酶复合物中。然而，如在毛地黄皂苷透化的细胞中所测量的，在携带突变的细胞中特异性降低约40%，这种降低在99.99%置信水平下是显著的，与突变细胞在含有半乳糖而不是葡萄糖的培养基中生长的能力显著降低相关，表明其氧化磷酸化能力明显受损。相反，没有减少鱼藤酮敏感的NADH脱氢酶活性，使用水溶性泛醌类似物作为电子受体，检测到在破坏线粒体膜。这是第一个在外来核背景下表现出视神经病变表型的线粒体DNA相关生化缺陷的细胞模型。
Mitochondrial DNA from two genetically unrelated patients carrying the mutation at position 11778 that causes Leber's hereditary optic neuropathy has been transferred with mitochondria into human mtDNA-less rho(0)206 cells. As analyzed in several transmitochondrial cell lines thus obtained, the mutation, which is in the gene encoding subunit ND4 of the respiratory chain NADH dehydrogenase (ND), did not affect the synthesis, size, or stability of ND4, nor its incorporation into the enzyme complex, However, NADH dehydrogenase-dependent respiration, as measured in digitonin-permeabilized cells, was specifically decreased by approximately 40% in cells carrying the mutation, This decrease, which was significant at the 99.99% confidence level, was correlated with a significantly reduced ability of the mutant cells to grow in a medium containing galactose instead of glucose, indicating a clear impairment in their oxidative phosphorylation capacity. On the contrary, no decrease in rotenone-sensitive NADH dehydrogenase activity, using a water-soluble ubiquinone analogue as electron acceptor, was detected in disrupted mitochondrial membranes. This is the first cellular model exhibiting in a foreign nuclear background mitochondrial DNA-linked biochemical defects underlying the optic neuropathy phenotype.