Abstract:

The paper aims to get insight into the MYB genes in Mirabilis himalaica. We used bioinformatics methods to screen the MYB genes from Mirabilis himalaica callus transcriptome data. The MYB protein sequences were identified by PlantTFDB 3.0 and BLASTP. At the same time, conserved domain was analyzed by using Web Logo 3.0 for those R2R3-MYB transcription factors with the largest proportion. Phylogenetic tree analysis was conducted by using Web MEGA 7.0 for all MhMYB. The expression levels of MhMYB under cold acclimation were analyzed by Mev. The results showed that 34 MYB genes were identified in Mirabilis himalaica, 30 of them belonged to R2R3-MYB, 2 of them belonged to 1R-MYB and 2 of them belonged to 3R-MYB. The subcellular localization prediction showed that MhMYB proteins were mostly localized in nucleus. The MhMYB proteins were divided into 15 subfamilies according to the classification method of Arabidopsis family. The homologous genes involved in flavonoids biosynthesis mainly belonged to the S2, S7 and S20 subfamilies. Gene expression analysis indicated that the expression level of MhMYB6, MhMYB15, MhMYB62 genes were up-regulated during cold-acclimation. Co-expression analysis showed that MhMYB6, MhMYB15 and MhMYB62 played a certain role in the regulation of flavonoids synthesis. This study shows that MhMYB genes play an important regulatory role in flavonoids biosynthesis and provides basic information for further exploration of the function of MhMYB genes.

Key words: Mirabilis himalaica, transcriptome, MYB gene family, bioinformatic analysis, flavonoid