National Institute of Livestock and Grassland Science, National Agriculture and Food Research Organization, Tsukuba 305-0901, Japan.
Mitochondrion. 2010 Mar;10(2):137-42. doi: 10.1016/j.mito.2009.12.144. Epub 2009 Dec 11.
Microinjection of isolated mitochondria into oocytes is an effective method to introduce exogenous mitochondrial DNA. In nuclear transfer procedures in which donor cell mitochondria are transferred with nuclei into recipient oocytes; development and survival rates of reconstructed embryos may be also directly influenced by mitochondrial viability. Mitochondrial viability is dramatically affected by cell culture conditions, such as serum starvation prior to nuclear transfer. This study was conducted to examine the influence of exogenous mitochondria using bovine and mouse parthenogenetic models. Mitochondria were isolated from primary cells at confluency and after serum starvation. The bovine oocytes injected with serum-starved mitochondria showed lower rates of morula and blastocyst formation when compared to uninjected controls (P<0.05). However, the developmental rates between non-starved mitochondria injection and controls were not different (P>0.05). The murine oocytes injected with serum-starved mitochondria showed lower rates of development when compared with non-starved mitochondria and controls (P<0.01). In contrast to mitochondria transfer, ooplasm transfer did not affect murine or bovine parthenogenetic development (P>0.05). The overall results showed that injection of serum-starved mitochondria influenced parthenogenetic development of both bovine and murine oocytes. Our results illustrate that the somatic mitochondria introduction accompanying nuclei has the capacity to affect reconstructed embryo development; particularly when using serum-starved cells as donor cells.
将分离的线粒体微注射到卵母细胞中是引入外源线粒体 DNA 的有效方法。在核转移过程中，供体细胞的线粒体与细胞核一起转移到受体卵母细胞中；重建胚胎的发育和存活率也可能直接受到线粒体活力的影响。线粒体活力受到细胞培养条件的显著影响，例如核转移前的血清饥饿。本研究使用牛和小鼠孤雌生殖模型来检查外源线粒体的影响。从汇合和血清饥饿后的原代细胞中分离出线粒体。与未注射对照相比，注射血清饥饿线粒体的牛卵母细胞的桑葚胚和囊胚形成率较低（P<0.05）。然而，非饥饿线粒体注射和对照之间的发育率没有差异（P>0.05）。与非饥饿线粒体和对照相比，注射血清饥饿线粒体的小鼠卵母细胞的发育率较低（P<0.01）。与线粒体转移相反，卵质转移不会影响小鼠或牛孤雌生殖的发育（P>0.05）。总体结果表明，注射血清饥饿的线粒体影响牛和小鼠卵母细胞的孤雌生殖发育。我们的结果表明，伴随细胞核引入的体线粒体具有影响重构胚胎发育的能力；特别是当使用血清饥饿的细胞作为供体细胞时。
