Genes trans-regulated by a novel hepatitis B virus preS2 antigen binding protein S2-29 by cDNA microarray

AIM: To study the biological functions of a novel hepatitis B virus preS2 antigen binding protein S2-29, and to analyze the gene expression profiles of HepG2 cell transfected with S2-29 gene. METHODS: S2-29 gene was screened and identified by using yeast two-hybrid system 3 and coimmunoprecipitation technique. Full-length encoding frame S2-29 and its amino acid sequences were identified by using bioinformatics method and the recombined eukaryotic expression plasmid pcDNA3.1(-)-S2-29 was constructed and transfected into HepG2 cells. Total mRNA was isolated from the HepG2 cells transfected with pcDNA3.1(-) and pcDNA3.1(-)-S2-29, respectively, cDNA microarray was employed for detecting and analysing of mRNA from the HepG2 cells. RESULTS: S2-29 cDNA sequence was obtained and identified by yeast two-hybrid screening and the bioinformatics analysis. Among 1 152 genes, there were 10 differences, of which 9 genes were upregulated and 1 gene were downregulated in HepG2 cells transfected with S2-29 protein expression plasmid. These genes differentially down-regulated by S2-29 protein included eukaryotic translation elongation factor 2, MAP-kinase activating death domain, glutathione peroxidase 5, gelsolin-like capping protein (actin filament), NDRG family member 2, prosaposin, SUMO-1 activating enzyme subunit 1, insulin receptor and a novel protein. CONCLUSION: Microarray technique is successfully used to screen the genes trans-regulated by S2-29, which brings some new clues for studying the trans-regulation and biological function of S2-29.