多效生长因子通过JNK信号通路负调控Schlafen2基因表达

Pleiotrophin Negatively Regulate Schlafen2 Gene Expression Through JNK Signal Pathway

实验室前期研究发现,多效生长因子(pleiotrophin,PTN)基因稳定沉默的小鼠胚胎成纤维细胞中Schlafen2(Slfn2)基因高表达.为了探讨Ptn沉默诱导Slfn2基因表达可能涉及的信号通路,应用Western印迹检测外源性PTN因子(终浓度50ng/μl)对Ptn沉默细胞JNK磷酸化水平的影响;应用Northern印迹分别检测JNK和p38通路特异性抑制剂对Ptn沉默细胞Slfn2基因转录水平的影响.结果发现,Ptn沉默细胞内JNK磷酸化水平高于对照细胞,外源性PTN处理后沉默细胞内JNK磷酸化水平下调;阻断JNK通路呈时间依赖性抑制Ptn沉默细胞中Slfn2基因转录,阻断p38通路对Ptn沉默细胞中Slfn2转录水平没有明显影响.结果提示,Ptn可能通过抑制其下游JNK/MAPK通路来负调控Slfn2的表达.

The expression of Schlafen2 （Slfn2） was up-regulated when knocking down pleiotrophin （Ptn） in mouse embryo fibroblast cells （MEF241）. To investigate the underlined signal pathway, we evaluated the effect of exogenous PTN on JNK phosphorylation and the S/fn2 transcription in response to JNK and p38 inhibitors by Western blot and Northern blot. We found that the level of JNK phosphorylation was higher in Ptn knocked down cells than in the control cells, and appeared to be down-regulated after exogenous PTN treatment. The Slfn2 transcription was inhibited by SP600128, but not SB203508. Our results indicated that JNK signal pathway was involved in the Ptn negative regulation of the S/fn2 transcription.