线粒体是在各类真核细胞中广泛存在的一种细胞器,主要参与细胞内能量供给、自由基生成和细胞凋亡等生物学过程。大量研究结果表明,线粒体功能紊乱与线粒体疾病、肿瘤的发生发展和耐药性产生以及衰老等密切相关。近年来,在线粒体基因组功能领域的研究有了飞速的发展,已初步认识到线粒体DNA转录起始需要线粒体RNA聚合酶、线粒体转录因子A、两个同源的线粒体转录因子B1或B2的同时存在,线粒体转录终止因子(mTERF)家族的成员则有可能在转录终止的过程中发挥作用,但某些方面的具体机制还有待进一步阐明。本文中将简要介绍近年来国内外在线粒体DNA的转录及调控等领域的研究进展情况。
Mitochondria are ubiquitous organelles found in all eukaryotic ceils and play an important role in cellular energy metabolism, free radical generation and apoptosis. Defects of rnitochondrial function contribute to many diseases, such as mitochondrial diseases, development and progression of cancer and aging. Recent years there have seen a rapid development in the understanding of mitochondrial genome. We have known that the initiation of transcription at mitochondrial promoters in mammalian cells requires the simultaneous presence of mitochondrial RNA polymerase, mitochondrial transcription factor A, and either transcription factor B1 or B2, and the component of mitochondrial transcription termination factor family may involved in the regulation of mitochondrial transcription termination. But many aspects still remain to be defined. In this review article, we provide a brief summary of current insights of the mitochondrial transcription machinery in mammalian cells.