Enhanced vitamin E content in an Indica rice cultivar harbouring two transgenes from Arabidopsis thaliana involved in tocopherol biosynthesis pathway.

Abstract

Micronutrient deficiency results in malnutrition, which is prevalent all over the world and may lead to premature death in women and children (White and Broadley, 2009). Strategies formulated earlier including supplementation and fortified foods were not successful, owing to socio-economic and technical hurdles (Mayer et al. 2008). The subsequently evolved strategy of bio-fortification is a viable biotechnological tool to achieve desired results without compromising the agronomical values of crops. Conferring the genetic trait to improve vital nutrient accumulation in the edible parts of staple food crops, such as rice, through metabolic engineering is considered a fast, sustainable, and cost-effective alternative to conventional breeding (Maestre et al. 2017). In earlier reports from our lab, enhanced α-tocopherol levels in the stable transformants of Nicotiana tabacum (Harish et al. 2013a, b) and in Nicotiana benthamiana adopting a transient expression system using A. thaliana tocopherol cyclase (TC) and homogentisate phytyl transferase (HPT) (Sathish et al. 2018) were shown. In the present study, Agrobacterium-mediated transformation of Indica rice ASD16 with two genes involved in tocopherol biosynthesis, viz., TC and HPT were carried out and the transgenic plants were analyzed for the vitamin E (α- tocopherol) content.