Wolf Don P, Hayama Tomonari, Mitalipov Shoukhrat
Center for Embryonic Cell and Gene Therapy, Oregon Health & Science University, Portland, OR, USA.
Division of Reproductive & Developmental Sciences, Oregon National Primate Research Center, Oregon Health & Science University, Beaverton, OR, USA.
EMBO J. 2017 Aug 1;36(15):2177-2181. doi: 10.15252/embj.201797606. Epub 2017 Jul 5.
Mitochondria, the ubiquitous power packs in nearly every eukaryotic cell, contain their own DNA, known as mtDNA, which is inherited exclusively from the mother. The number of mitochondrial genomes varies depending on the cell's energy needs. The mature oocyte contains the highest number of mitochondria of any cell type, although there is little if any mtDNA replication after fertilization until the embryo implants. This has potential repercussions for mitochondrial replacement therapy (MRT; see description of currently employed methods below) used to prevent the transmission of mtDNA-based disorders. If only a few mitochondria with defective mtDNA are left in the embryo and undergo extensive replication, it might therefore thwart the purpose of MRT In order to improve the safety and efficacy of this experimental therapy, we need a better understanding of how and which mtDNA is tagged for replication versus transcription after fertilization of the oocyte.
线粒体是几乎每个真核细胞中普遍存在的能量供应者，它们含有自己的DNA，即线粒体DNA（mtDNA），其遗传方式为母系遗传。线粒体基因组的数量因细胞的能量需求而异。成熟卵母细胞是所有细胞类型中线粒体数量最多的，不过受精后直到胚胎着床，线粒体DNA几乎没有复制。这对于用于预防基于线粒体DNA的疾病传播的线粒体替代疗法（MRT；见下文当前使用方法的描述）具有潜在影响。如果胚胎中仅留下少数具有缺陷线粒体DNA的线粒体并进行大量复制，那么这可能会阻碍线粒体替代疗法的目的。为了提高这种实验性疗法的安全性和有效性，我们需要更好地了解卵母细胞受精后线粒体DNA如何以及哪些被标记用于复制而非转录。
