Objective: To investigate the function and mechanism of transcription factor of MEIS1 and miR-425 to the proliferation of chronic myeloid leukemia cell K562.
Methods: Bioinformatic prediction was used to analyze the binding of MEIS1 in miR-425 promoter region. ChIP-qPCR coupled with dual luciferase assay was used to detect the combination of MEIS1 and the transcription activity of miR-425, and its regulative role in the transcription activity miR-425. CCK-8 was used to detect the effect of MEIS1 and miR-425 on cell proliferation. Flow cytometry with PI staining was used to detected the effect of MEIS1 and miR-425 on K562 cell cycle progression. Western blot was used to examine the effect of miR-452 on the expression level of MEIS1.
Results: MEIS1 could bind the promoter of miR-425 and repressed its transcription. After K562 was transfected by shRNA, the K562 cell proliferation and cell cycle progression was significantly inhibitied. Moreover, after K562 cells were transfected by miR-425 mimic, cell proliferation and cell cycle was inhibited. The expression level of MEIS1 could be inhibited by the combination of miR-425 and MEIS1 3'UTR.
Conclusion: MEIS1 can inhibit the activity of miR-425 in transcriptional level, while the miR-425 can suppress the expression of MEIS1 protein in post-transnational level. Therefore, a regulatory circuit comprising from MEIS1 and miR-425 regulates K562 cell proliferation.
题目: MEIS1/miR-425反馈调节通路对慢性髓系白血病细胞株K562增殖的作用.
目的: 研究转录因子MEIS1和miR-425对人慢性髓系白血病细胞株K562增殖的调控作用及其分子机制.
方法: 通过生物信息学预测分析转录因子MEIS1在miR-425启动子区的结合位点情况，ChIP-qPCR结合双荧光报告基因实验检测MEIS1与miR-425启动子的结合情况及其对miR-425启动子的调节作用，CCK-8法检测MEIS1和miR-425对K562细胞增殖的影响，PI染色结合流式细胞术检测MEIS1和miR-425对K562细胞周期的影响，Western blot检测miR-425对MEIS1表达的影响.
结果: MEIS1可以与miR-425启动子区结合，并可抑制其活性。使用针对MEIS1的shRNA转染K562细胞后，可显著抑制K562细胞增殖及细胞周期的运行。类似地，使用miR-425的模拟物转染K562细胞后，也可抑制K562细胞的增殖和细胞周期的运行。miR-425可以通过与MEIS1 3′UTR的结合抑制MEIS1的表达.
结论: 转录因子MEIS1可在转录水平抑制miR-425的转录活性，miR-425则在转录后水平抑制MEIS1蛋白的表达，因此，两者共同构成一个反馈调节通路作用于K562细胞的增殖.