University of Calcutta (U of C), Kolkata
PI: Dr Karabi Datta
Low phytate rice development:To develop low phytate rice, appA gene was cloned from Escherichia coli genomic DNA.Embryo and endosperm specificZein promoter was cloned from maize (Zea mays) genomic DNA. Over-expression vector was constructed with appA gene under the control of zein promoter. Seven low phytate transgenic lines were developed showing 30-50% reduction in phytic acid level. Mineral content of transgenic lines were significantly higher than that of the non-transgenic control.
Low phytate rice: Over expression of E.coli phytase gene
Lysine content increment: Two approaches are being attempted viz., Seed specific expression of less feedback sensitive bacterial DHDPS (dihydrodipicolinate synthase) enzyme and RNAi mediated downregulation of bifunctional lysine degrading LKR/SDH (lysine ketoglutarate reductase/saccharopine dehydrogenase) enzyme. The first approach for lysine content increment in rice, DHDPS gene from Corynebacterium glutamicum was cloned under zein promoter and rice transformation was done with the vector. Four lines were initially selected by molecular analysis. Analysis of amino acid content reveals that lysine content has been improved in transgenic seeds by1.5 times of that of the WT).For the second approach, lkr/sdh gene fragment (452bp) was isolated from cDNA of rice (Oryza sativa) and RNAi vector was constructed with glutelinC promoter from rice in destination vector. Rice transformation was performed by Agrobacterium mediated transformation method. Analysis of amino acid content reveals that lysine content is improved in transgenic seeds of the down regulation lines (2.6 times of that of the WT).
Ferritin: Proteomics profiling of Ferritin rice - Comparative 2-DE analysis between WT and soybean ferritin overexpression transgenic rice plants showed 14 and 10 differentially accumulated protein species in the seeds and shoot respectively. Most of the differentially accumulated protein species identified from seeds were found to be involved with storage whereas protein species from leaves belong to energy and carbon metabolism. No allergens or toxic nature of the identified protein species has been detected..
2DE and MALDI-TOF MS/MS analysis between WT (IR68144) and transgenic plants. Outer layer: seed; Inner layer: shoot
β-carotene: Metabolic study of carotenoid enriched rice line - GC-MS based metabolite profiling exhibited enhancement of the levels of glyceric acid, fructo-furanose, and galactose, while decrease in galactonic acid and gentiobiose in the transgenic rice compared to WT. 2D based proteomic study of transgenic golden rice and control rice seeds was done to identify differentially expressed proteins. 2D based proteomic analysis of carotenoids enriched golden rice demonstrated that carbohydrate metabolism-related enzymes were primarily up-regulated in transgenic rice seeds.