Xenopus egg extract treatment reduced global DNA methylation of donor cells and enhanced somatic cell nuclear transfer embryo development in pigs

• Published in: BioResearch open access 2012-04, Vol.1 (2), p.79-87
• Main Authors: Yang, Xiaoyu, Mao, Jiude, Walters, Eric M, Zhao, Ming-Tao, Teson, Jennifer, Lee, Kiho, Prather, Randall S
• Format: Article
• Language: English
• Subjects: Original s; Xenopus
• ISSN: 2164-7844; 2164-7860; 2164-7860
• DOI: 10.1089/biores.2012.0214

The efficiency to produce offspring by somatic cell nuclear transfer (SCNT) is low. It has been showed that treatment of donor cells with Xenopus oocyte extract increased live births in ovine and handmade cloned embryo development in pigs. Scriptaid treatment after oocyte activation is another approach to improve SCNT efficiency. The present study was carried out to investigate (a) the effects of treatment of donor cells with Xenopus egg extract on donor cell DNA methylation at days 0 and 4 with two digitonin permeabilization concentrations (10 and 15 μg/mL), (b) the effects of treatment of donor cells with Xenopus egg extract on early development of cloned embryos, and (c) the effects of combined treatments, treating donor cells with extract before nuclear transfer and treatment of cloned embryos with scriptaid after oocyte activation, on embryo development. Compared to the control, a decrease of DNA methylation in donor cells was observed at 2.5 h after extract treatment. However, this effect was not observed after the cells were cultured for four more days. More embryos developed into blastocysts in the Xenopus egg extract-treated group than in the control (13.4±1.9% vs. 9.1±1.9%, p=0.01). Furthermore, scriptaid treatment of cloned embryos further increased the frequency of development to blastocyst, compared to the control reconstructed with the same extract-treated cells (22.5±0.9% vs. 15.3±0.9%, p