1 Faculty of Science, SDU2 Department of Biochemistry and Molecular Biology, Faculty of Science, SDU3 unknown4 Department of Biochemistry and Molecular Biology, Faculty of Science, SDU
Mouse embryos at various stages of development were used to study the relationship of protein kinase activities with normal embryogenesis. Casein kinase II (CKII) activity in developing mouse embryos shows a 3-4-fold activity increase at day 12 of gestation. Together with the CKII activity, increased phosphorylation of a 110-kDa protein is observed. Treatment of the embryo extracts with heparin, a highly specific inhibitor of CKII activity, results in a drastic reduction of the 110-kDa protein phosphorylation indicating that the protein might be a CKII-specific substrate. Rapidly proliferating mouse tumour cells also show an enhanced CKII activity. Here too, a 110-kDa phosphoprotein was the major phosphoryl acceptor. Partial proteolytic digestion shows that both proteins are identical. Other protein kinases tested (cAMP- and cGMP-dependent protein kinases) only show a basal level of enzyme activity with minor alterations throughout the different stages of embryogenesis investigated.
European Journal of Biochemistry, 1986, Vol 161, Issue 3, p. 733-738
Animals; Autoradiography; Carcinoma, Krebs 2; Casein Kinases; Centrifugation, Density Gradient; Embryo, Mammalian; Embryonic and Fetal Development; Mice; Molecular Weight; Peptide Mapping; Phosphoproteins; Phosphorylation; Protein Kinases