Recombinant human activin A promotes development of bovine somatic cell nuclear transfer embryos matured in vitro
S. Hua, J. Lan, Y.G. Liu, Y.L. Song, J. Liu, Y.S. Wang, T. Zhang, Y. Zhanghttps://doi.org/10.17221/298/2009-CJASCitation:Hua S., Lan J., Liu Y.G., Song Y.L., Liu J., Wang Y.S., Zhang T., Zhang Y. (2010): Recombinant human activin A promotes development of bovine somatic cell nuclear transfer embryos matured in vitro. Czech J. Anim. Sci., 55: 267-275.
To improve the culture system of bovine somatic cell nuclear transfer (SCNT) embryos, we studied the effects of activin A on developmental competence of bovine SCNT embryos during the early development stage based on the traditional culture method, and analyzed the expression level of the genes related to blastocyst hatching (Na/K-ATPase, Glut-1) and related to activin A signalling pathway (ActRII and Smad2). We generated the bovine SCNT embryo using a Holstein cow oocyte as recipient cytoplasm and a foetal ear fibroblast (Holstein cow, 120 days) as donor cell. The embryos were cultured as follows: experiment 1, the addition of activin A at the concentrations of 0 (control), 20 (M1–20), 40 (M1–40) or 80 ng/ml (M1–80) to the media during the first three days and no addition during the subsequent 5 days; experiment 2, no addition of activin A to the media during the first 3 days and the addition of activin A at the concentrations of 0 (control), 20 (M2–20), 40 (M2–40) or 80 ng/ml (M2–80) during the subsequent 5 days. The results indicated that the blastocyst formation rate and hatching rate, and total blastomere numbers as well as ICM/TE obtained in experiment 1 were not significantly different from the control group (P > 0.05). In contrast, these values obtained in experiment 2 were significantly higher than in the control group (P < 0.05). In addition, the relative abundance (ratio to GAPDH mRNA) of each gene (Glut-1, ActR II and Smad2) was not significantly different among the treatments in the experiment. The expression levels of 4 genes (Na/K-ATPase, Glut-1, ActR II and Smad2) in blastocysts obtained in experiment 2 were higher than those obtained in experiment 1. In conclusion, the present study suggests that the addition of activin A to the culture media from day 4 to day 8 can enhance the developmental competence of bovine SCNT embryos.Keywords:
activin A; SCNT; embryo development; bovine