Different fates of donor mitochondrial DNA in bovine-rabbit and cloned bovine-rabbit reconstructed embryos during preimplantation development

State Key Laboratory of Reproductive Biology, Institute of Zoology, Chinese Academy of Sciences, Beijing 100080, China.
Frontiers in Bioscience (Impact Factor: 3.52). 02/2006; 11(1):1425-32. DOI: 10.2741/1893
Source: PubMed


The functions of mitochondria depend on precise interaction between nuclear and cytoplasmic genomes. Non-balance of mtDNA has been reported in most nuclear transfer embryos and offspring. The reason of the degradation of donor mtDNA is still not clear. To further investigate the mechanism, in this study, we designed an experiment as follows. Two fibroblast cell lines sharing same nuclear genome but different mitochondria genome backgrounds, namely cells from ear tissues of cloned bovine and its donor, were choose as donor cells and introduced into enucleated rabbit oocytes. Similar developmental potential was observed in cloned bovine-rabbit (clone group) and bovine-rabbit (non-clone group) embryos. Real-time PCR assay showed that, in non-clone group, bovine mtDNA decreased during the development of reconstructed embryo, and that a sharp decrease was detected at the blastocyst stage. In clone group, bovine mtDNA decreased slightly, and the abrupt reduction of donor mtDNA did not occur during preimplantation development. In addition, an obvious increase in rabbit mtDNA was observed in both groups at the blastocyst stage. Our results demonstrate that: 1) the fates of donor mtDNAs in bovine-rabbit and cloned bovine-rabbit reconstructed embryos were different; and 2) recipient mtDNAs replicate at blastocyst regardless of the difference of donor cells.

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    • "However, development of canine–pig iSCNT blastocysts was reported in 2009 (Sugimura et al., 2009).Rabbit oocytes. Rabbit oocytes were found to be good recipients when shown to support preimplantation development of embryos derived from nuclei of several species, including bovine (Jiang et al., 2006), Capra ibex (Jiang et al., 2005), chicken (Liu et al., 2004), camel and Tibetan antelope (Zhao et al., 2006), macaca (Yang et al., 2003), cat and panda (Wen et al., 2005), human (Shi et al., 2008), and even chicken (Liu et al., 2004). However, microarray analysis failed to detect significant human genome reprogramming in human– rabbit iSCNT embryos (Chung et al., 2009). "
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