Changes in phosphorylation pattern of regulatory proteins after X-irradiation of mouse embryos during 2-cell stage

Phosphoproteins are the major key molecules responsible for the regulation of the complex network of cellular responses to external signals. Especially the signal transduction pathways and the control of the cell cycle are regulated by phosphorylated enzymes and substrate molecules. Studies have identified the phosphorylation of tyrosine residues to be one of the crucial mechanisms mediating the proliferation and differentiation of cells. The aim of our study was to analyze the patterns of phosphoproteins of murine preimplantation embryos after irradiation with various doses (3-6 Gy). We tried to find out if there are changes in phosphorylation patterns at the transition from the four-cell stage to the eight-cell stage which are a result of a dose dependent radiation effect. Investigations were made to prove which influence X-irradiation has on regulatory mechanisms during the third cell cycle. We tried to characterize proteins with an altered phosphorylation pattern to find out if these proteins could be regulatory elements involved in the cell cycle control. (author)