Shimoizumi H, Momoi M Y, Ohta S, Kagawa Y, Momoi T, Yanagisawa M
Department of Pediatrics, Jichi Medical School, Tochigi-ken, Japan.
Ann Neurol. 1989 Jun;25(6):615-21. doi: 10.1002/ana.410250614.
In a patient with mitochondrial myopathy, the defect of cytochrome c oxidase activity was restricted to some muscle fibers. To isolate cell lines with or without oxidase activity from a single muscle sample, primary cultured cells were transformed by replication origin-defective simian virus 40, and then cloned. The clones were examined by cytochemical staining for cytochrome c oxidase activity. Eight myogenic clones were completely devoid of activity, while the other myogenic and nonmyogenic clones were not. Deficiency of cytochrome c oxidase was stable in culture for at least a year after serial passaging. The amount of mitochondrial DNA in cytochrome c oxidase-deficient cells was the same as in control cells, and no deletion in the mitochondrial DNA was detected. Protein synthesis in mitochondria of the subunits of cytochrome c oxidase and subunit 6 of the ATP synthase complex was markedly decreased, whereas synthesis of the other subunits encoded by mitochondrial DNA was normal. These cloned cell lines provide an excellent system for clarifying the cause of mitochondrial myopathy and for investigating nuclear-mitochondrial genetic interaction.
在线粒体肌病患者中，细胞色素c氧化酶活性缺陷仅局限于部分肌纤维。为了从单个肌肉样本中分离出具有或不具有氧化酶活性的细胞系，原代培养细胞用复制起点缺陷型猿猴病毒40进行转化，然后进行克隆。通过细胞化学染色检测克隆细胞的细胞色素c氧化酶活性。八个肌源性克隆完全没有活性，而其他肌源性和非肌源性克隆则有活性。细胞色素c氧化酶缺乏在连续传代培养中至少稳定一年。细胞色素c氧化酶缺陷细胞中的线粒体DNA量与对照细胞相同，未检测到线粒体DNA缺失。细胞色素c氧化酶亚基和ATP合酶复合体亚基6在线粒体中的蛋白质合成明显减少，而由线粒体DNA编码的其他亚基的合成正常。这些克隆细胞系为阐明线粒体肌病的病因和研究核-线粒体基因相互作用提供了一个极好的系统。
