Szabados G, Adám-Vizi V, Hegyi K, Horváth I
Acta Biochim Biophys Acad Sci Hung. 1979;14(3):155-64.
The incorporation of (3H) thymidine into isolated rat liver mitochondria in the presence of 0--0.5 mM ATP was stimulated by a polyanion with an average molecular weight of 10 000 daltons (at 50--200 micrograms/ml concentration) and containing in a proportion of 1 : 2 : 3 methacrylate, maleate and styrene. The above concentrations of the polyanion inhibit the incorporation of (3H) thymidine in the presence of 2 mM ATP and have no substantial effect on (14C)isoleucine incorporation in vitro. The mtDNA synthesis stimulatory effect of the polyanion is independent of its inhibitory effect on adenylate translocase. The polyanion does not enhance the nucleotide transport across the inner membrane of the mitochondria and the changes of thymidine phosphorylating activity are not involved in the increased mtDNA synthesis. It is supposed that the polyanion attached to the inner membrane of the mitochondria alters the binding of mtDNA to the inner membrane of the mitochondria. Thus, the polyanion might be an effective tool in studying the functional significance of mtDNA-membrane association in mtDNA replication.
在0-0.5 mM ATP存在的情况下，一种平均分子量为10000道尔顿（浓度为50-200微克/毫升）且甲基丙烯酸酯、马来酸和苯乙烯比例为1:2:3的聚阴离子可刺激（3H）胸苷掺入分离的大鼠肝线粒体。上述聚阴离子浓度在2 mM ATP存在时会抑制（3H）胸苷的掺入，且对体外（14C）异亮氨酸掺入没有实质性影响。聚阴离子对线粒体DNA合成的刺激作用与其对腺苷酸转位酶的抑制作用无关。聚阴离子不会增强核苷酸跨线粒体内膜的转运，且胸苷磷酸化活性的变化与线粒体DNA合成增加无关。推测附着在线粒体内膜上的聚阴离子改变了线粒体DNA与线粒体内膜的结合。因此，聚阴离子可能是研究线粒体DNA-膜结合在线粒体DNA复制中的功能意义的有效工具。
