PDGF-BB和SDZ RAD对血管平滑肌细胞p27基因启动子活性和p27 mRNA表达的影响

Effect of platelet-derived growth factor-BB and SDZ RAD on the promoter activity of p27 gene and p27 mRNA expression in rat vascular smooth muscle cell

目的探讨重组大鼠血小板衍化生长因子(platelet-derived growth factor-BB,PDGF-BB)和抗增殖剂SDZ RAD对大鼠血管平滑肌细胞(vascular smooth muscle cells,VSMC)p27基因启动子活性和p27 mRNA表达的影响。方法构建含p27基因启动子序列与氯霉素乙酰基转移酶(chloramphenicol acetyl transferase,CAT)报告基因的重组体pXp27,将这个重组体瞬时转染大鼠VSMC,加入PDGF-BB和SDZ RAD干预,测定CAT活性。用RT-PCR法测定其对p27 mRNA表达的影响。结果10ng/ml的PDGF-BB使转染后的重组体CAT活性降低,且使VSMC p27 mRNA表达量显著下降。10ng/ml的SDZ RAD则使重组体CAT活性增高,并使VSMC p27 mRNA表达量显著增加。结论PDGF-BB或SDZ RAD分别在基因转录水平或促进p27抑制基因启动子活性,进而减少或增加其mRNA的表达。

Objective To study the effect of platelet-derived growth factor-BB （PDGF-BB） and SDZ RAD on the promoter activity of p27 gene and p27 mRNA expression in rat vascular smooth muscle cells （VSMCs）. Methods The deletion constructs, pXp27, containing region of p27 gene promoter ligated to the chloramphenicol acetyltransferasc （CAT） reporter gene, were transiently transfected into VSMCs. The transfected VSMCs were subsequently treated with PDGF-BB or SDZ RAD. Twenty-four hours later, the CAT activity and the expression level of p27 mRNA were detected by CAT enzyme-linked immunosorbent assay and RT-PCR, respectively. Results PDGF-BB （ 10 ng/ml） decreased the CAT activity of pXp27 and significantly decreased p27 mRNA expression level, while SDZ RAD （ 10 ng/ml） increased the CAT activity of pXp27 and significantly decreased p27 mRNA expression level. Conclusion PDGF-BB inhibits and SDZ RAD increases the promoter activity of p27 gene in rat VSMCs, then both further act on the mRNA expression of p27 gene.