视网膜母细胞瘤基因产物部分性质的研究

Study on Characters of Rb Gene Product

研究Ｒｂ基因产物的代谢动力学和功能调节，发现整个细胞周期中都有Ｒｂ蛋白合成，其含量随细胞周期进行而变化，蛋白代谢的半衰期约为１１—１２小时，有非磷酸化和多种程度磷酸化形式。Ｒｂ蛋白的磷酸化水平是随细胞周期过程和细胞生长状态而变化的，在Ｇ０、Ｇ１期蛋白处于低磷酸化状态，到达Ｇ１／Ｓ界限，细胞获得磷酸化Ｒｂ蛋白的能力．

Analysis of Rb protein showed that the protein had a half time of more than 10 hours, and was synthesized at all phases of cell cycle. It could be phosphorylated. Regulation of phosphoryla non and quantity of Rb protein were cell-cycle-dependent. Newly synthesized Rb protein was underphosphorylated in cells at G, and G, phases, and was phosphorylated at multiple sites at G1/S boundary and in S phase. The underphosphorylated Rb protein may restrict the cell proliferation.