Vila J, Payne D M, Zioncheck T F, Harrison M L, Itarte E, Weber M J
Departament de Microbiologia, Hospital Clinic i Provincial de Barcelona, Facultat de Medicina, Spain.
FEBS Lett. 1990 May 7;264(1):21-4. doi: 10.1016/0014-5793(90)80754-7.
Because examination of regulatory trans-phosphorylations can help elucidate the cellular functions of tyrosyl protein kinases, we have investigated the effects of phosphorylation by casein kinase-1 on the activity of the p40 tyrosyl protein kinase. We find that casein kinase-1 can phosphorylate the p40 tyrosyl kinase on serine and threonine residues, in part on a unique tryptic peptide. The phosphorylation induces a substantial increase in the tyrosyl protein kinase activity of p40, in contrast to most instances in which serine/threonine phosphorylation inhibits activity of tyrosyl protein kinases. These findings raise the possibility that p40 might be part of a protein phosphorylation network in which casein kinase-1 participates.
由于对调节性转磷酸化的研究有助于阐明酪氨酰蛋白激酶的细胞功能，我们研究了酪蛋白激酶-1磷酸化对p40酪氨酰蛋白激酶活性的影响。我们发现酪蛋白激酶-1可使p40酪氨酰激酶的丝氨酸和苏氨酸残基磷酸化，部分磷酸化发生在一个独特的胰蛋白酶肽段上。与大多数丝氨酸/苏氨酸磷酸化抑制酪氨酰蛋白激酶活性的情况相反，这种磷酸化使p40的酪氨酰蛋白激酶活性大幅增加。这些发现提示p40可能是酪蛋白激酶-1参与的蛋白质磷酸化网络的一部分。
