Munday M R, Carling D, Hardie D G
Department of Biochemistry, University, Dundee, Scotland.
FEBS Lett. 1988 Aug 1;235(1-2):144-8. doi: 10.1016/0014-5793(88)81251-1.
We have reported previously that cyclic AMP-dependent protein kinase phosphorylates two sites on acetyl-CoA carboxylase (site 1: Arg-Met-Ser(P)-Phe, and site 2: Ser-Ser(P)-Met-Ser-Gly-Leu), while the AMP-activated protein kinase also phosphorylates site 1, plus site 3 (Ser-Ser-Met-Ser(P)-Gly-Leu), the latter being two residues C-terminal to site 2. We now report that prior phosphorylation of site 2 by cyclic AMP-dependent protein kinase prevents the subsequent phosphorylation of site 3 and the consequent large decrease in Vmax produced by the AMP-activated protein kinase. Similarly, prior phosphorylation of site 3 by the AMP-activated protein kinase prevents subsequent phosphorylation of site 2 by cyclic AMP-dependent protein kinase.
我们之前报道过，环磷酸腺苷依赖性蛋白激酶会使乙酰辅酶A羧化酶的两个位点发生磷酸化（位点1：精氨酸-甲硫氨酸-丝氨酸（磷酸化）-苯丙氨酸，位点2：丝氨酸-丝氨酸（磷酸化）-甲硫氨酸-丝氨酸-甘氨酸-亮氨酸），而AMP激活的蛋白激酶也会使位点1发生磷酸化，同时还会使位点3（丝氨酸-丝氨酸-甲硫氨酸-丝氨酸（磷酸化）-甘氨酸-亮氨酸）发生磷酸化，位点3位于位点2的C末端两个残基处。我们现在报道，环磷酸腺苷依赖性蛋白激酶对位点2的预先磷酸化会阻止随后位点3的磷酸化以及AMP激活的蛋白激酶导致的Vmax大幅下降。同样，AMP激活的蛋白激酶对位点3的预先磷酸化会阻止环磷酸腺苷依赖性蛋白激酶随后对位点2的磷酸化。
