Potential of VlmybA1-2 as a Candidate Marker for Visual Identification of Transgenic Plants: Induced Anthocyanin Production in Arabidopsis and Tobacco

For development of a safe and efficient in vivo marker for plant transformation, an myb-related gene of anthocyanin biosynthetic pathway, VlmybA1-2 from grape, was introduced into anthocyanin producing tobacco and Arabidopsis, and non- anthocyanin producing spinach under the control of CaMV 35S promoter. Except for the distinguishable purple color, transformed calli and plants of tobacco were not different from controls. RNA gel blot hybridization confirmed the expression of VlmybA1-2 in purple tobacco seedlings. Completely purple T1 Arabidopsis seedlings could not survive as high anthocyanin levels may affect normal growth; Surviving T1 seedlings could produce viable seeds of two distinguishable colors: purple and brown (similar to wild type). Purple seeds germinated on kanamycin medium providing an easy method of transgenic seed identification in Arabidopsis. T2 and T3 completely purple seedlings produced purple flowers and seeds. Putative transgenic spinach was not different to control in color, although presence of VlmybA1-2 was confirmed by DNA gel blot hybridization. VlmybA alone, without the aid of an myc-related gene partner, could induce complete pigmentation in tobacco and Arabidopsis indicating its potential over previously used myb- and myc-related genes.

Key words: Anthocyanin; Arabidopsis; In vivo marker; Tobacco; VlmybA1-2

DOI: 10.4038/tare.v12i1.1982

Tropical Agricultural Research & Extension 12(1):2009 35-41