目的检测乙型肝炎病毒X蛋白(hepatitis B virus X protein,HBx)对人血管生成因子bFGF基因转录的激活作用并确定其作用于bFGF基因启动子的区域,分析HBx激活bFGF基因转录可能的分子机制,为揭示HBx促进肝癌发生的分子机制及发现新的治疗靶...目的检测乙型肝炎病毒X蛋白(hepatitis B virus X protein,HBx)对人血管生成因子bFGF基因转录的激活作用并确定其作用于bFGF基因启动子的区域,分析HBx激活bFGF基因转录可能的分子机制,为揭示HBx促进肝癌发生的分子机制及发现新的治疗靶点。方法运用高保真DNA聚合酶从人肝癌HepG2细胞cDNA文库中扩增出bFGF基因启动子DNA序列;从含完整HBV DNA序列的表达载体中扩增HBx编码序列并克隆入真核表达载体p CDNA3-FLAG中,将HBx表达载体转染人肝癌HepG2细胞中,裂解细胞进行蛋白SDS-PAGE电泳,Western blot检测HBx蛋白的表达;将HBx表达载体和含bFGF基因启动子不同区段的荧光素酶报告载体共转染肝癌HepG2和SMMC-7721细胞,检测HBx对bFGF基因启动子转录活性的影响;运用Western blot检测在肝癌细胞中HBx过表达对ERK磷酸化的影响。结果成功克隆了HBx并使其在肝癌细胞中得到表达;成功克隆了bFGF基因启动子2.2 kb、1.4 kb、720 bp和360 bp的区段;在肝癌细胞SMMC-7721和HepG2细胞中HBx的表达能升高bFGF基因启动子的活性,且对上述4个区段的活性均增加约5倍;HBx以剂量依赖的方式增强bFGF基因启动子的活性;HBx高表达在肝癌HepG2细胞中不能升高ERK1/2的磷酸化水平。结论HBx能够激活bFGF基因启动子的活性,这种激活作用位于HBx启动子转录起始位点上游360 bp片段内,HBx促进bFGF基因转录不依赖于ERK1/2的磷酸化作用,提示HBx可能通过其它信号通路作用于bFGF基因的转录过程。展开更多
[ Objective] The study is to generate pharmaceutical protein via plant transgenic technique. [Methed] Using the cotyledons with petiole as transformation receptor, the fusion gene of rapeseed oil-body gene and bFGF wa...[ Objective] The study is to generate pharmaceutical protein via plant transgenic technique. [Methed] Using the cotyledons with petiole as transformation receptor, the fusion gene of rapeseed oil-body gene and bFGF was introduced into the rapeseed （ Brassica campestris L. ） by Agrobacterium tumefaciens-mediated transformation; meanwhile regeneration conditions of rapeseed were also optimized, and the regenerated resistant plantlets were detected by PCR and Southern blot. [ Result] This fusion gene had been integrated into rapeseed genome successfully, and the optimized conditions of transformation and regeneration were as follows： explants pre-culture for 2 d, co-culture for 3 d, bacteria solution OD600 for 0.3 and infection time for 5 min. [ Conclusion] The results laid a solid foundation for extraction, isolation and purification of protein in transgenic plant seeds.展开更多
基金Supported by Bioreactor Important Special Item of 863-Program inthe "Eleventh Five-Year" Plan (No. 2007AA100503)Science and Technology Development Key Plan of Jilin Province( No.20070922)+1 种基金Cultivation Fund of Scientific and Technical Innovation Project Major Program of Higher Education Institutions ( No.70S018)Science and Technology Plan of Changchun City (No.06GG150)~~
文摘[ Objective] The study is to generate pharmaceutical protein via plant transgenic technique. [Methed] Using the cotyledons with petiole as transformation receptor, the fusion gene of rapeseed oil-body gene and bFGF was introduced into the rapeseed （ Brassica campestris L. ） by Agrobacterium tumefaciens-mediated transformation; meanwhile regeneration conditions of rapeseed were also optimized, and the regenerated resistant plantlets were detected by PCR and Southern blot. [ Result] This fusion gene had been integrated into rapeseed genome successfully, and the optimized conditions of transformation and regeneration were as follows： explants pre-culture for 2 d, co-culture for 3 d, bacteria solution OD600 for 0.3 and infection time for 5 min. [ Conclusion] The results laid a solid foundation for extraction, isolation and purification of protein in transgenic plant seeds.
