14-3-3σ调控p27抑制Rat1-Akt细胞增殖

目的： 研究腺病毒介导14-3-3·σ（Ad-14-3-3·σ）对Akt过表达Rat1-Akt细胞增殖的影响，并探讨其作用是否通过调控p27而实现。 方法： 通过5-溴-2′脱氧尿嘧啶（BrdU）实验检测Ad-14-3-3·σ对Rat1-Akt细胞增殖的影响，并通过激酶分析法和免疫荧光实验探讨Ad-14-3-3·σ对p27磷酸化水平及其在细胞内定位的影响。 结果： Ad-14-3-3σ转染的细胞BrdU阳性率（45%）低于PBS处理组（100%）或Ad-β-gal转染的对照组细胞（98%）。14-3-3σ可降低磷酸化p27的水平和减少Akt介导的p27在胞浆中的定位。 结论： 转染14-3-3σ基因能抑制Akt过表达细胞株Rat1-Akt增殖，14-3-3σ通过降低Akt激酶磷酸化p27的活性，阻断Akt介导的p27胞浆错位，从而发挥其抑制Rat1-Akt细胞增殖。

14-3-3σ regulates p27 and inhibits Rat1-Akt cell proliferation

AIM: The present study was designed to investigate the effect of adenovirus-mediated 14-3-3σ on the proliferation of Rat1-Akt cells and to explore whether this effect is completed regulating p27.METHODS: The effect of Ad-14-3-3σ gene transfection on Rat1-Akt cell proliferation was observed by using 5-bromodeoxyuridine (BrdU).Then immunofluorescence and kinase assay were used to detect the effect of Ad-14-3-3σ on the phosphorylated level and intracellular location of p27.RESULTS: Ad-14-3-3σ-infected cells had fewer BrdU-positive cells (45%) than control (which was set at 100%).However,Ad-β-gal-infected cells had a high percentage of BrdU-positive cells (98%).14-3-3σ gene transfection downregulated phosphorylation level of p27 and decreased Akt-mediated intracellular location of p27.CONCLUSION: Transfection of 14-3-3σ gene suppresses the proliferation of Akt overexpession cell line Rat1-Akt.14-3-3σ decreases phosphorylation of p27 by downregulating Akt kinase,blocks Akt-mediated cytoplasm dislocation of p27,and inhibits proliferation of Rat1-Akt cells.