Abstract:

Abstract:Objective
To observe the expression and localization of protein kinase Wee1B in mouse one-cell-stage embryos, and to pay foundation for further study on the mechanism of the early development of mouse embryos. Methods One-cell-stage  mouse embryos were collected after superovulation,and the mRNA and protein expression levels of Wee1B were examined by RT-PCR and Western blotting,respectively.The Wee1B activity in mouse embryos was detected by autoradiography and the localization of Wee1B in each cell cycle was observed by indirect immunofluorescence.Results There were no significant differences in the expression levels of Wee1B mRNA between G₁, S, G₂ and M phases (P＞0.05); but there were significant differences in the expression levels of Wee1B protein between S, G2 , M phases and G1 phase (P＜0.01).Compared with G1 phase, the activities of Wee1B in G₂  phase and S phase were increased (P＞0.05， P＜0.01)，but the activity of Wee1B in M  phase was decreased (P＜0.01). Wee1B  distributed in the nucleus at the G₁ and S phases and translocated to the cytoplasm at the G2/M transition in one-cell-stage embryos.Conclusion The protein and activity of Wee1B are dynamically expressed in one-cell-stage embryos and the nucleocytoplasmic shuttling of Wee1B may be the mechanism of early development of mouse embryos. 

Key words: Wee1B；Wee1 protein；mouse zygote；protein expression, protein localization