Levels of cyclin D protein drop upon withdrawal of growth factors through downregulation of its protein expression and through phosphorylation-dependent degradation (4).
生长因子退出后，通过下调蛋白表达和磷酸化依赖性蛋白降解，周期蛋白D的水平下降（4）。
2
Specific signaling motifs include not only sequences that are recognized by protein kinases (1), but also those that are recognized by phosphorylation-dependent binding proteins such as 14-3-3 (2).
Subsequently, we monitored the ligand-dependent HER profiles based on receptor expression, phosphorylation, and dimerization in conjunction with measurements of cellular susceptibility to gefitinib.