The insect expressing vectors could express Cyclin D1 and CDK4 proteins which possessed ability of phosphorylating Rb protein, showing biological activity.

• 研究表明 ；昆虫细胞表达的细胞周期蛋白D1和CDK4蛋白能促进Rb蛋白的磷酸化 ；具有生物活性 .