Qualitative and quantitative analysis of the Nictaba promoter activity during development in Nicotiana tabacum

Nictaba is a genuine jasmonate inducible lectin expressed in the leaves and roots of Nicotiana tabacum cv. Samsun NN. Although the jasmonate pathway is generally highly conserved among plant species, recent research showed that it is followed by plant specific downstream processes. Previously the Nictaba promoter activity was studied in the model plant Arabidopsis thaliana, using the β-glucuronidase (GUS) as a gene reporter system. In this paper the promoter activity of Nictaba was analyzed in N. tabacum plants stably expressing a promoter-GUS fusion construct. Both histochemical and fluorometric techniques were used to follow Nictaba promoter activity during the development of the tobacco plants. GUS staining was predominantly detected in the cotyledons, the leaves and the roots during the youngest plant stages. As the plants grow older GUS staining was mostly present in the older leaves. A detailed comparative analysis was made of the GUS staining results obtained in transgenic Arabidopsis and tobacco lines.