Abstract: Green fluorescent protein(Gfp) and beta-glucuronidase(Gus) are two widely used reporter genes, which have advantages and disadvantages for qualitative analysis and quantitative determination of gene expression and promoter activity in molecular studies. A vector carrying an enhanced Gfp/Gus (eGfp/Gus) dual reporter gene was constructed to establish an efficient and convenient screening system for gene and promoter studies in plants. Primers with specific restriction endonuclease sites were designed according to sequences of the reporter genes. The eGfp and Gus genes were amplified respectively by PCR method. With corresponding endonucleases, the genes and the primary vector pFGC5941 were digested, and then these three fragments were ligated in one reaction to make a final vector. The vector, designated pFGC-DR, is characterized with a strong constitutive promoter CamV35S driving the eGfp/Gus fusion gene. Transient expression in tobacco leaves and transgenic expression studies in Arabidopsis showed that this fusion reporter protein retains functional activity for both eGfp and Gus. These results demonstrated the utility of the eGfp/Gus dual reporter system for studying of plant promoters．

Key words: eGfp/Gus dual reporter gene, plant expression vector, transient expression, transgenic plants