Hashizume H, Yoneda M, Kanemoto K
J Biochem. 1983 Sep;94(3):961-6. doi: 10.1093/oxfordjournals.jbchem.a134439.
Murine splenocyte nuclei were phosphorylated with a less than 10(-5) M concentration of [gamma-32P]ATP at 0 degrees C and the phosphorylated nuclear proteins were analyzed by SDS-polyacrylamide gel slab electrophoresis and Sephadex gel filtration column chromatography. Two polypeptides of 10K and 11K daltons were predominantly phosphorylated. These polypeptides were likely linked by a disulfide bond to form a nonhistone protein of 21K daltons. Both phosphoserine and phosphothreonine were detected in the hydrolysate of the 10.5K dalton polypeptide, while phosphoserine was predominant in the 10K dalton polypeptide. Maximal activation of phosphorylation by cAMP of both polypeptides was shown at a concentration of 10(-6) M. On the contrary, cGMP activated phosphorylation of the 10K dalton polypeptide at 10(-8) M and at 10(-4) M. The phosphorylation of the 10.5K polypeptide was not activated by 10(-4) M cGMP and suppression of the phosphorylation was seen in both polypeptide chains by cAMP at higher concentrations.
在0℃下，用浓度低于10^(-5) M的[γ-32P]ATP对小鼠脾细胞核进行磷酸化，然后通过SDS-聚丙烯酰胺凝胶平板电泳和葡聚糖凝胶过滤柱色谱法分析磷酸化的核蛋白。主要被磷酸化的是两种分子量分别为10K和11K道尔顿的多肽。这些多肽可能通过二硫键相连，形成一种分子量为21K道尔顿的非组蛋白。在10.5K道尔顿多肽的水解产物中检测到磷酸丝氨酸和磷酸苏氨酸，而在10K道尔顿多肽中磷酸丝氨酸占主导。两种多肽在浓度为10^(-6) M的cAMP作用下磷酸化达到最大激活。相反，cGMP在10^(-8) M和10^(-4) M时激活10K道尔顿多肽的磷酸化。10.5K多肽的磷酸化在10^(-4) M的cGMP作用下未被激活，且在较高浓度的cAMP作用下，两条多肽链的磷酸化均受到抑制。
