Functional Characterization Of Medicago Truncatula MtMYB114 And MtGL2 Transcription Factors In Transgenic Alfalfa

Alfalfa is one of the most important legume forages in the world. Its excellent forage value and high yield laid its position in animal husbandry. But it is easy to cause ruminant livestock’s bloat after feeding alfalfa, severely limiting the nutritional potential of alfalfa. Condensed tannins is an important product in the flavonoid biosynthetic pathway that can inhibit bloat. With the rapid development of genetic engineering, it is possible to improve the content of condensed tannins in alfalfa by using biotechnology methods. Now we get the following results:1. In this paper, we studied MtMYB114 and MtGL2 genes from M. truncatula, which is homologous species with alfalfa. Through the bioinformatics analysis we found that these two genes showed identity.2. By using Agrobacterium mediated method, we had transformed these two regulators into alfalfa successfully. We generated 43 MtMYB114 over-expressing transgenic plants and 40 MtGL2 over-expressing transgenic plants in total. Through real-time quantitative techniques, we found that the relative expression of DFR and ANR genes which are key genes in the biosynthetic pathway of flavonoids included condensed tannins and anthocyanins increased at different levels.3. Additionally, the transgenic plants displayed purple color in callus period, indicating the accumulation of anthocyanin which is precursor of condensed tannin in these transgenic plants.Above experimental results showed that overexpression of MtMYB114 and MtGL2 genes could increase the expression of key genes in the biosynthetic pathway of flavonoid, at least increase the content of anthocyanin which is precursor of condensed tannin. It provided reference for the breeding of anti-bloat alfalfa.