中文摘要：

目的利用抑制性消减杂交技术筛选重组β-干扰素（IFN-β）上调HepG2细胞表达基因。方法以重组IFN-β2000U·mL^-1刺激对数生长期HepG2细胞，设经0．9％氯化钠注射液作用的HepG2细胞为阴性对照组；制备HepG2细胞裂解液，从中提取mRNA并逆转录合成cDNA，经RsaⅠ酶切后，将实验组cDNA分成两组，分别与两种不同的接头衔接，再与阴性对照组cDNA进行两次消减杂交和两次抑制性聚合酶链反应（PCR），将产物与T／A栽体连接，构建cDNA消减文库，并转染大肠埃希菌进行基因文库扩增，随机挑选克隆PCR后进行测序及同源性分析。结果成功构建了重组IFN-β作用HepG2后差异表达的cDNA消减文库。扩增后得到50个200～1000bp插入片段的克隆，随机挑选其中31个插入片段测序，通过生物信息学分析获得其全长基因序列，共获得20种编码基因，其中1种为未知功能的新基因。结论通过该方法可筛选得到IFN-β作用于HepG2细胞后上调表达的部分基因，包括与细胞生长调节、物质代谢和细胞凋亡密切相关的一些蛋白编码基因。

英文摘要：

Objective To clone and identify human genes transactivated by recombinant β-interferon protein. Methods Suppression subtractive hybridization （SSH） and bioinformatics techniques were used for screening and cloning of the target genes transactivated by recombinant β-interferon protein. The mRNA was isolated from HepG2 cells induced by recombination β-interferon and 0.9 percent sodium chloride, respectively, and the SSH method was employed to analyze the differentially expressed DNA sequences between the two groups. After the restriction enzyme Rsa Ⅰ digestion, small size cDNAs were obtained. Tester cDNA was then divided into two groups and linked up to the specific adaptor 1 and adaptor 2, respectively. After the tester cDNA had been hybridized twice with the driver cDNA and had undergone two times of nested PCR, the products were subcloned into T/A plasmid vectors to set up the subtractive library. Amplification of the library was carried out with transfeetion of E. coli strain DH5α. The cDNA was sequenced and analyzed in Genbank with Blast search after PCR. Results The cDNAs differentially expressed by genes transactivated by recombinant β-interferon protein were successfully constructed. The amplified library contained 50 positive clones. Colony PCR showed that 31 clones contained 200-1 000 bp inserts. Sequence analysis was performed in 31 clones randomly, and the full-length sequences were obtained with the bioinformatics method. Altogether 20 coding sequences were obtained, including a new gene with unknown function. Conclusion The sequences obtained may be target genes transactivated by recombinant β-interferon protein, and some of these genes coding proteins may be involved in cell cycle regulation, metabolism, and apoptosis.