Expression of 2S Seed Storage Protein Gene of Brassica juncea in Transgenic Tobacco Plants under Constitutive and Seed-specific Promoters

The coding and upstream promoter regions of Brassica juncea 2S seed storage protein gene were amplified by polymerase chain reaction. The plant expression cassettes containing 2S seed storage protein gene under the control of either a constitutive Caulimovirus 35S promoter or a seed specific 2S protein promoter and the polyadenylation signal of a pea rbcS gene were used for Agrobacterium - mediated transformation of tobacco (Nicotiana tabacum cv Petit Havana). Integration of 2S gene was confirmed by Southern blot and PCR analysis of plant genomic DNA. Expression of introduced 2S protein gene was monitored by slot blot analysis of total RNA using 2S protein sequence as hybridization probe and also by immunodot blot analysis using specific antiserum of 2S protein. Expression was either constitutive with CaMV 35S promoter or highly seed-specific with Brassica 2S promoter.