VvMYBA6 in the promotion of anthocyanin biosynthesis and salt tolerance in transgenic Arabidopsis

Abstract

Transcription factor MYB is a critical factor involved in anthocyanin biosynthesis and abiotic stress resistance of plants. This paper reports the functions of codon-optimized transcription factor VvMYBA6 expressed in transgenic Arabidopsis plants. VvMYBA6 overexpression resulted in significant increase of anthocyanin content, which also enhanced salt and mannitol tolerance in transgenic Arabidopsis plants. Besides, real-time quantitative PCR (qRT-PCR) analysis showed that overexpression of VvMYBA6 promoted the expression level of genes involved in anthocyanin biosynthesis, abscisic acid (ABA) synthesis, proline synthesis, stress responses and ROS scavenging under salt and mannitol stress. According to further analysis under salt and mannitol stress, overexpression of VvMYBA6 significantly increased ABA and proline content, activities of superoxide dismutase (SOD), peroxidase (POD) and catalase (CAT), as well as reduced the content of H2O2 and malonaldehyde (MDA). The results demonstrated that the overexpression of VvMYBA6 enhanced salt and mannitol tolerance based on increasing synthetic levels of anthocyanin and ABA in transgenic Arabidopsis plants. Therefore, the overexpression of VvMYBA6 could be widely used in promoting salt tolerance in plants.