Constitutive expression of the ARGOS gene driven by dahlia mosaic virus promoter in tobacco plants

The auxin-inducible gene ARGOS from Arabidopsis thaliana is expressed in growing tissues and controls the plant organ size by regulating cell proliferation and meristematic competence. The promoter of the dahlia ( Dahlia pinnata Cav.) mosaic virus (DMV) resembles the well-known cauliflower mosaic virus 35S promoter but shows a higher activity in transgenic tobacco plants ( Nicotiana tabacum L.). We obtained transgenic tobacco plants expressing the Arabidopsis ARGOS gene under the control of the DMV promoter. Several of the T0 generation plants exhibited an accelerated transition to flowering, a slight increase in flower size, and a significant increase in the leaf size. The T1 transgenic plants were characterized by faster growth, the increased leaf size, and somewhat enlarged flowers as compared with control plants. These phenotypic traits, as well as stability and inheritance of the transgene were demonstrated also in T2 transgenic plants.