[摘要] 目的：探讨丝氨酸和富含精氨酸剪接因子1（SRSF1）基因对神经胶质瘤U87 细胞增殖和细胞周期的影响及其作用机制。方法：采用基因沉默技术抑制SRSF1 基因表达，获得2 种不同靶点的SRSF1 稳定沉默细胞系（shSRSF1-1 组和shSRSF1-2组）。用CCK-8 法检测SRSF1 沉默对神经胶质瘤U87 细胞的增殖活性，流式细胞技术检测SRSF1 沉默对U87 细胞周期的影响，qPCR和WB实验检测SRSF1 沉默对细胞分裂相关基因（CEP70 和SMC4）mRNA和蛋白表达水平的影响，用WB实验检测SRSF1沉默对翻译起始蛋白4E-BP1 磷酸化的影响。结果：shSRSF1-1 组和shSRSF1-2 组U87 细胞中SRSF1 蛋白表达均明显低于对照组（P<0.01），shSRSF1-1 组和shSRSF1-2 组U87 细胞增殖能力被显著抑制（P<0.01），并且处在G2 期的细胞数量明显高于对照组（P<0.01）。与对照组比较，shSRSF1-1 组和shSRSF1-2 组细胞中细胞分裂相关基因CEP70 和SMC4 mRNA水平无明显差异（P>0.05），但是蛋白表达水平明显降低（P<0.01）。shSRSF1-1 组和shSRSF1-2 组U87 细胞中翻译起始蛋白4E-BP1 磷酸化程度要明显低于对照组（P<0.01）。结论：沉默SRSF1 基因通过降低翻译起始蛋白4E-BP1 磷酸化水平抑制细胞分裂相关基因CEP70和SMC4 的翻译过程，最终使细胞阻滞在G2 期，进而减弱神经胶质瘤U87细胞的增殖能力。

[Abstract] Objective: To investigate the effect of serine and arginine rich splicing factor 1 (SRSF1) on proliferation and cell cycle of U87 cells and to explore the underlying mechanisms. Methods: Gene silencing technology was used to knockdown SRSF1, and stable SRSF1 knockdown cell lines with two different targeting sites (shSRSF1-1 and shSRSF1-2) were obtained. Cell counting kit (CCK-8) was performed to detect proliferation of U87, and flow cytometry was performed to detect cell cycle of U87 with or without SRSF1 knockdown. qPCR and WB were used to detect the mRNA and protein expressions of cell division related genes (CEP70 and SMC4). WB was performed to detect the effect of SRSF1 knockdown on phosphorylation of translation initiation protein 4E-BP1. Results: Compared with control group, the protein level of SRSF1 was significantly decreased in U87 cells of shSRSF1-1 and shSRSF1-2 groups (P<0.01), and the proliferation was significantly decreased (P<0.01); in addition,U87 cells were remarkably arrested at G2 phasein shSRSF1-1 and shSRSF1-2 groups (P<0.01). Although the mRNA levels of CEP70 and SMC4 did not change significantly (P>0.05), the protein levels of CEP70 and SMC4 were lower in U87 cells of shSRSF1-1 and shSRSF1-2 groupsas compared with control group (all P<0.01). And the levels of phosphorylated 4E-BP1 were also inhibited in U87 cellsof shSRSF1-1 and shSRSF1-2 groups as compared with control group (P<0.01). Conclusion: SRSF1 knockdown decreased the phosphorylation of 4EBP1 and inhibited the translation process of CEP70 and SMC4, there by resulting in cell cycle retardant in G2 phase and proliferation repression of glioma U87 cells.