视网膜母细胞瘤基因产物磷酸化水平与细胞生长状态的关系

随着无血清培养细胞时间的延长，红胞合成Ｒｂ蛋白量和磷酸化水平逐渐降低，当细胞生长停止时，Ｒｂ蛋白处于低磷外化状态．正丁酸钠可诱导ＨＬ６０终端分化为单核－巨噬细胞；视黄酸、二甲基亚砜使ＨＬ６０分化为粒细胞．尽管分化途径不同．但是终端分化的细胞都只能合成低磷酸化的Ｒｂ蛋白．结果表明当细胞处于生长停滞状态，细胞都只能合成低磷酸化的Ｒｂ蛋白．

Study on the Relationship between Phosphorylation of Rb Protein and Statuses of Cell Growth

Synthesis of Rb protein were decreased in quiescent cells arrested by serum free medium, and newly synthesized Rb protein were underphosphorylated. Sodium butyrate could induce HL60 cell to differentiate into monocyte-macrophage. Retinoic acid and dimethylsulfoxide induced HL60 cell to differentiate into granulocyte. Terminally differentiated HL60 cells only synthesized underphosphorylated Rh protein. These results stated that cells synthesized underphosphorylated Rb protein when cells were at status of non-growing. Proliferatillg cells could express extensively phosphorylated Rb protein