Fig. 2

Pak2 knockdown disrupts the developmental potential of early embryos. In vitro culture of zygotes microinjected with Pak2-siRNA and analysis of developmental progression. A, With GAPDH as a loading control, the efficiency of Pak2 knockdown was confirmed by western blot analysis. B, Band intensity was calculated using ImageJ software (NIH, USA), and the ratio of Pak2/GAPDH expression was normalized and the values are indicated. C, Representative bright-field images of 2-cell embryos, 4-cell embryos, 8-cell embryos, and blastocysts from control and Pak2-KD groups. Bule asterisks indicate examples of normal morphology; red asterisks indicate examples of abnormal morphology (scale bars, 100 μm). D, Quantification analysis of the rate of 2-cell, 4-cell, 8-cell and blastocyst in control embryos and Pak2-KD embryos. (2-cell: 82.3 ± 1.76%, n = 118 vs. 80.5 ± 1.82%, n = 127, respectively; 4-cell: 71.7 ± 1.85%, n = 103 vs. 51.8 ± 1.73%, n = 82, respectively; 8-cell: 61.7 ± 1.93%, n = 89 vs. 21.2 ± 1.36%, n = 33, respectively; blastocyst: 44.3 ± 1.13%, n = 63 vs. 11.47 ± 1.62%, n = 18, respectively). The graph shows the mean perentage ± SD of the results obtained in three independent experiments. *Significantly different (p < 0.05). Pak2, p21-activated kinase 2; SD, standard deviation; Pak2-KD, Pak2 knockdown; BL, blastocyst