Prosaposin对细胞增殖和凋亡的调控及其分子机制  

Studies of effect of prosaposin on cell proliferation,cell apoptosis and its possible molecular mechanism

作　　者：郭芬[1,2] 罗志文[1] 刘兆宇[1] 李月琴[1] 李弘剑[1] 周天鸿[1] 

机构地区：[1]暨南大学基因工程药物国家工程研究中心,广州510632 [2]广东药学院生命科学与生物制药学院,广州510006

出　　处：《遗传》2009年第12期1226-1232,共7页Hereditas（Beijing)

基　　金：广东省自然科学基金项目(编号:8151063201000013);"211"工程经费项目资助

摘　　要：为研究鞘脂激活蛋白原(Prosaposin)对细胞增殖、细胞凋亡的调控及其可能的分子机制,以pcDNA3.1 in NIH3T3阴性对照细胞株和过表达prosaposin的Psap-Myc in NIH3T3细胞株为模型,噻唑蓝(MTT)比色法检测prosaposin对细胞增殖的影响;Annexin V联合碘化丙啶(Propidium iodide,PI)法检测血清饥饿状态下prosaposin对细胞凋亡的影响;Western blotting检测PI3K/Akt信号通路中蛋白磷酸化水平的变化;Real-time PCR检测PI3K/Akt信号通路下游靶分子表达水平的改变。结果表明prosaposin可活化PI3K/Akt信号通路,提高AktSer473的磷酸化水平,抑制细胞周期抑制基因P27KIP1的表达,上调细胞周期蛋白Cyclin D1的表达,促进细胞周期从G1→S期进展;诱导survival基因cIAP1、cIAP2的表达,促进细胞存活。这些结果提示,prosaposin对细胞增殖和凋亡的调控可能是通过PI3K/Akt信号通路及其下游靶分子进行的。pcDNA3.1 in NIH3T3 and Psap-Myc in NIH3T3 cell strains were used as cell models in order to study the effect of prosaposin on cell proliferation, cell apoptosis and its possible molecular mechanism. MTT assay and Annexin V/PI apoptosis kit were used to detect the effect of prosaposin on cell proliferation and cell apoptosis induced by serum-starvation stress, respectively. Western blotting was conducted to detect the phosphorylative level of PI3K/Akt pathway and real-time PCR was carried out to explore the expression of the genes regulated by PI3K/Akt pathway. Prosaposin protein was proved to activate the PI3K/Akt signal pathway, upregulate the phosphorylative activity of Akt at Serine 473, downregulate the expression of P27^Kip1 gene, upregulate the expression of Cyclin D1 gene and then promote the G1/S transition, and upregulate the expression of survival genes clAP1 and clAP2 and then prevent cell apoptosis. These findings suggest that the growth promotion and anti-apoptotic activity of prosaposin may be partly through the PI3K/Akt signal pathway and its downstream targeted genes.

关 键 词：鞘脂激活蛋白原 细胞增殖 细胞凋亡 P13K/AKT信号通路 基因表达 

分 类 号：Q343[生物学—遗传学]