Background: Low digestibility of seed storage proteins (kafirins) and low nutritional grain value are one of the most important directions of genetic improvement of sorghum. In this review, we summarize experiments on improving protein digestibility, and increasing nutritional value of sorghum grain using genetic engineering approaches, primarily, by the introduction of genetic constructs that cause the silencing of γ-and/or α-kafirins. Key points of improvement of Agrobacterium-mediated genetic transformation, which was used for introduction of these genetic constructs in sorghum genome, are discussed. Transgenic sorghum harboring the genetic constructs inducing silencing of kafirins are characterized by reduction of kafirin oligomers, an increase of in vitro digestibility of proteins of flour, an increase in the proportion of essential amino acids, lysine, in particular, a changes in the ultrastructure of endosperm protein bodies (in case of α-kafirin silencing), which acquire an irregular shape with invaginations, and modification of endosperm texture, which become floury devoid of the vitreous layer. In some cases transgenic events with vitreous endosperm and high digestibility of kafirins were observed, which, in this connection, may be of interest for practical sorghum breeding. There are evidences that in vitro protein digestibility in transgenic plants with genetic construct for γ-kafirin silencing grown in the field plot was substantially lower than in the plants grown in the pots in greenhouse conditions. These facts indicate that suppression of the synthesis of kafirins occurring at epigenetic level as a result of the expression of the genetic constructs for silencing, is influenced by environment. In this connection, the use of methods of genome editing, in particular, editing the nucleotide sequences of the α-or γ-kafirin genes, opens wider prospects for improving the digestibility of kafirins and increasing the nutritional value of sorghum grain. Current approaches for biofortification of sorghum grain with amino acids and micronutrients are discussed.Citation: Elkonin L, Italyanskaya J, Panin V. Genetic modification of sorghum for improved nutritional value: state of the problem and current approaches.Citation: Elkonin L, Italyanskaya J, Panin V. Genetic modification of sorghum for improved nutritional value: state of the problem and current approaches.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
customersupport@researchsolutions.com
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.