Wieprecht M, Wieder T, Geilen C C, Orfanos C E
Institute of Molecular Biology and Biochemistry, University Medical Center Benjamin Franklin, Free University of Berlin, Germany.
FEBS Lett. 1994 Oct 17;353(2):221-4. doi: 10.1016/0014-5793(94)01040-4.
The effect of insulin and epidermal growth factor on the phosphorylation of CTP:phosphocholine cytidylyltransferase (EC 2.7.7.15) was investigated in HeLa cells. For the first time, cytidylyltransferase phosphorylation was shown to be influenced by growth factors in cell culture experiments. The rephosphorylation of cytidylyltransferase after an oleate-mediated dephosphorylation and translocation to membranes was increased after 2 min in the presence of insulin or epidermal growth factor by 99% and 76%, respectively, compared with controls. However, the increased phosphorylation of cytidylyltransferase did not have an effect on its subcellular distribution. Furthermore, purified cytidylyltransferase preincubated with alkaline phosphatase is a substrate for p44mapk, a member of the mitogen-activated protein (MAP) kinase family downstream of the growth factor receptors, in vitro. In accordance with the in vivo data, in vitro phosphorylation of cytidylyltransferase by p44mapk occurred after 2 min.
在HeLa细胞中研究了胰岛素和表皮生长因子对CTP：磷酸胆碱胞苷转移酶（EC 2.7.7.15）磷酸化的影响。首次在细胞培养实验中表明胞苷转移酶的磷酸化受生长因子影响。与对照组相比，在油酸介导的去磷酸化和转位至膜后，在胰岛素或表皮生长因子存在下2分钟后，胞苷转移酶的再磷酸化分别增加了99%和76%。然而，胞苷转移酶磷酸化的增加对其亚细胞分布没有影响。此外，与碱性磷酸酶预孵育的纯化胞苷转移酶在体外是促分裂原活化蛋白（MAP）激酶家族下游生长因子受体成员p44mapk的底物。与体内数据一致，p44mapk在2分钟后使胞苷转移酶发生体外磷酸化。
