短发夹状RNA抑制SMYD3基因在HepG2细胞中的表达

Suppression of SMYD3 expression in HepG2 cell by shRNA interference

目的构建针对人SET-和MYND-结构域含有蛋白3(SMYD3)基因的短发夹状RNA (shRNA)表达载体pGenesil-1-s,观察其对人肝癌细胞株HepG2细胞SMYD3基因表达的特异性抑制效应。方法设计合成针对SMYD3 mRNA编码序列267～288、302～323靶位点之间的核苷酸片断,并定向克隆到仅表达EGFP的空载体pGenesil-1的U6启动子下,构建重组质粒pGenesil-1-s1、pGenesil-1-s2；不针对任何序列的重组质粒pGenesil-1-hk作为对照。通过脂质体介导转染人肝癌细胞株HepG2,应用逆转录聚合酶链反应,western blot蛋白免疫印迹法分别从mRNA、蛋白水平检测阻抑效应。结果酶切鉴定和测序结果证实了pGenesil-1-s1、pGenesil-1-s2、pGenesil-1-hk的成功构建,转染HepG2细胞后,pGenesil-1- s1、pGenesil-1-s2组SMYD3 mRNA和蛋白表达均明显下调,与pGenesil-1-hk组及pGenesil-1对照组比较差异有统计学意义(P＜0.01)。结论构建的重组质粒pGenesil-1-s1、pGenesil-1-s2能特异性抑制SMYD3 在HepG2细胞中的表达。

Objective To identify the inhibition effect of shRNA on the SMYD3 （SET- and MYND-domain containing protein-3） expression in hepatoma cell line HepG2 through gene silencing. Methods Two reverse repeated motifs targeting on the SMYD3 mRNA sequences 267-288, 302-323 respectively, were synthesized and inserted into the mock plasmid pGenesil-1 which expressed EGFP to create recombinant plasmids pGenesil-1-s1 and pGenesil-1-s2, pGenesil-1-hk specific to no SMYD3 mRNA sequence served as a control. After transfection into HepG2 cells, RT-PCR and western blot were applied to identify the down regulation of SMYD3 expression by shRNAs. Results All plasmids were constructed successfully, pGenesil-1-s1, pGenesil-1-s2 inhibited the mRNA and protein expression of SMYD3 in HepG2 cells. There was a significant distinction when compared with pGenesil-1-hk and pGenesil-1 （P 〈 0.01）. Conclusion Short hairpin RNAs can efficiently and specifically suppress the expression of SMYD3 in HepG2 cells.