SETD4蛋白在Bac-to-Bac杆状病毒系统的表达

Expression of SETD4 in Bac-to-Bac baculovirus expression system

目的通过昆虫杆状病毒表达系统表达SETD4(SET domain-containing 4)蛋白,并纯化SETD4蛋白,为深入探讨SETD4的功能奠定基础。方法提取小鼠正常肝组织的RNA,通过RT-PCR扩增SETD4基因,并克隆至p Fast Bac-HTB构建重组载体,再转座获得重组杆粒;通过脂质体介导将重组杆粒转染SF9细胞产生重组病毒,扩增病毒感染细胞并获得重组蛋白;利用Ni2+亲和柱来纯化蛋白,并通过Western Blot及考马斯亮蓝染色鉴定SETD4蛋白。结果经双酶切鉴定及测序证实SETD4基因插入了供体质粒;经PCR鉴定证实SETD4基因插入了穿梭载体;经考马斯亮蓝染色证实纯化得到重组蛋白,用His-Tag抗体和SETD4特异性抗体在50 k D处可检测到目的条带。结论成功利用昆虫杆状病毒表达系统够表达了SETD4,并纯化了SETD4。

Objective To express SET domain-containing 4 （SETD4） protein through using baculovirus expression system and purify the expressed product to explore the functions of SETD4 protein and further understand the biological roles of SET family proteins. Methods The SETD4 gene was amplified by RT-PCR from mouse normal liver tissue. The gene was then inserted into pFastBac-HTB vector to form the recombinant donor plasmid which was further transformed into DH10Bac to construct the recombined bacmid. Next the bacmid was transfected to sf9 cells for package of the recombinant baculovirus particles. The recombinant SETD4 protein was expressed from the cells transduced by the recombinant baculovirus and was purified by NI-NTA resin. Purified protein was examined by coomassie brilliant blue staining and Western Blotting. Results The donor plasmid and recombined bacmid were successfully prepared and the recombinant baculovirus particles were produced from sf9 cells. The SETD4 protein was obtained and confirmed by brilliant blue staining and western blotting with a His-tag antibody and a specific SETD4 antibody. Conclusions The recombinant SETD4 protein was successfully expressed and prepared through baculovirus expression system.