title: The proteasomal inhibitor MG132 increases the efficiency of mouse embryo production after cloning by electrofusion.
abstract: In this study, we cloned mice from ES cells by a post-electrofusion MG132 treatment and improved development of cloned embryos with a sequential cultivation protocol. When 5 microM MG132, a proteasome inhibitor, were used to treat the reconstructed embryos, the capacity of in vitro development, implantation and full-term development were significantly improved. Blastocyst formation rates of the reconstructed embryos from X4 ES cells (F1 strain derived from C57BL/6 x 129sv) and J1 ES cells obtained with or without MG132 treatment were 66.9% and 26.6%, and 66.1% and 34.5% respectively (P < 0.05). A total of 146 two-cell embryos cloned from X4 ES cells with MG132 treatment were transferred to recipients, and five cloned pups (3.4%) were born, of which four survived. When the same numbers of two-cell embryos cloned from X4 ES cells without MG132 treatment were transferred, however, no live-born mice were obtained. When embryos cloned from J1 ES cells without MG132 treatment were cultured in KSOM medium for 54 h followed by culture in CZB medium containing 5.6 mM glucose for 42 h, the blastocyst rate was significantly higher than when they were cultured in KSOM continuously for 96 h (34.5% vs 17.1%). However, sequential cultivation did not improve the development of embryos cloned with MG132 treatment and that of parthenotes. In conclusion, MG132 treatment increased the developmental potential of reconstructed mouse embryos, and sequential cultivation improved development of the embryos cloned by electrofusion without MG132 treatment.
authors.affiliation: Department of Cell Biology, College of Life Sciences, Beijing University, Beijing 100871, China, Beijing Laboratory Animal Research Center, Beijing 100012, China.
authors.forename: Yuansong
authors.initials: Y
authors.lastname: Yu
authors.forename: Jun
authors.initials: J
authors.lastname: Yong
authors.forename: Xiangyun
authors.initials: X
authors.lastname: Li
authors.forename: Tingting
authors.initials: T
authors.lastname: Qing
authors.forename: Han
authors.initials: H
authors.lastname: Qin
authors.forename: Xiaoran
authors.initials: X
authors.lastname: Xiong
authors.forename: Jiefang
authors.initials: J
authors.lastname: You
authors.forename: Mingxiao
authors.initials: M
authors.lastname: Ding
authors.forename: Hongkui
authors.initials: H
authors.lastname: Deng
mesh_terms: D000818:Animals; D002478:Cells, Cultured; D019976:Cloning, Organism / Q000379:methods*; D018274:Electroporation; D010064:Embryo Implantation; D004624:Embryo Transfer; D047108:Embryonic Development / Q000187:drug effects; D005260:Female; D007976:Leupeptins / Q000494:pharmacology*; D051379:Mice; D008810:Mice, Inbred C57BL; D008811:Mice, Inbred DBA; D053652:Nuclear Transfer Techniques; D009865:Oocytes; D010312:Parthenogenesis; D011480:Protease Inhibitors / Q000494:pharmacology*
chemical_list: D007976:Leupeptins; D011480:Protease Inhibitors; C072553:benzyloxycarbonylleucyl-leucyl-leucine aldehyde