rbcS SRS4 promoter from Glycine max and its expression activity in transgenic tobacco.

The regulatory region of the ribulose-1,5-bisphosphate carboxylase small subunit gene SRS4 from soybean (Glycine max) was cloned using TAIL-PCR and general PCR, and named the rbcS promoter. The promoter was fused with the GUS gene and introduced into Nicotiana tabacum via Agrobacterium-mediated leaf disk transformation. In 4-week-old transgenic tobacco plants, the highest GUS expression levels were observed in the leaves, GUS activity was 7.13- and 7.40-fold higher in leaves than in stems and roots, respectively. Moreover, GUS activity was stimulated by light. In conclusion, spatial and light regulation of the soybean rbcS promoter was observed in N. tabacum, thus illustrating a leaf-specific and light-induced promoter.