Department of Theriogenology & Biotechnology, College of Veterinary Medicine, Seoul National University, Seoul, Republic of Korea.
PLoS One. 2012;7(8):e41256. doi: 10.1371/journal.pone.0041256. Epub 2012 Aug 15.
Mature oocytes can be parthenogenetically activated by a variety of methods and the resulting embryos are valuable for studies of the respective roles of paternal and maternal genomes in early mammalian development. In the present study, we report the first successful development of parthenogenetic canine embryos to the post-implantation stage. Nine out of ten embryo transfer recipients became pregnant and successful in utero development of canine parthenotes was confirmed. For further evaluation of these parthenotes, their fetal development was compared with artificially inseminated controls and differentially expressed genes (DEGs) were compared using ACP RT-PCR, histological analysis and immunohistochemistry. We found formation of the limb-bud and no obvious differences in histological appearance of the canine parthenote recovered before degeneration occurred; however canine parthenotes were developmentally delayed with different cell cycle regulating-, mitochondria-related and apoptosis-related gene expression patterns compared with controls. In conclusion, our protocols were suitable for activating canine oocytes artificially and supported early fetal development. We demonstrated that the developmental abnormalities in canine parthenotes may result from defective regulation of apoptosis and aberrant gene expression patterns, and provided evidence that canine parthenotes can be a useful tool for screening and for comparative studies of imprinted genes.
成熟卵母细胞可以通过多种方法进行孤雌激活，由此产生的胚胎对于研究父本和母本基因组在早期哺乳动物发育中的各自作用非常有价值。在本研究中，我们报告了首例成功发育至植入后阶段的犬孤雌胚胎。十只胚胎移植受体中有九只怀孕成功，证实了犬孤雌胚胎在子宫内的成功发育。为了进一步评估这些孤雌胚胎，我们使用 ACP RT-PCR、组织学分析和免疫组织化学比较了它们的胎儿发育情况，并与人工授精对照组进行了比较。我们发现形成了肢芽，在退化发生之前，犬孤雌胚胎的组织学外观没有明显差异；然而，与对照组相比，犬孤雌胚胎的发育延迟，细胞周期调控、线粒体相关和凋亡相关基因的表达模式不同。总之，我们的方案适用于犬卵母细胞的人工激活，并支持早期胎儿发育。我们证明了犬孤雌胚胎的发育异常可能是由于凋亡的调节缺陷和异常的基因表达模式所致，并为犬孤雌胚胎可作为筛选和印迹基因比较研究的有用工具提供了证据。
