Analysis of MYB genes in four plant species and the detection of genes associated with drought resistance

Abstract

MYB transcription factor, which contains a conserved DNA binding domain, has been found in almost all eukaryotes. MYB genes have variable functions in plants and are involved in many pathways. We systemically analyzed the MYB gene family in three Ericaceae species, Rhododendron williamsianum Rehder & E.H. Wilson, Rhododendron delavayi Franch., and Vaccinium corymbosum L., and one outgroup, Actinidia chinensis Planch., with 99, 156, 480, and 185 MYB genes found, respectively. The MYB genes were classified into five types based on the number of conserved MYB motifs, and the two repeat (2R) types were dominant in all four species. The percentage of 2R type MYB ranged from 48.5% to 87.9% depending on the species. We further classified the conserved MYB motifs into M1, M2, and M3 types based on motif definition. We found an abundance of 3xM2 type in the 3R group, but found a species-specific type preference for 1R and 2R genes. In searching for Arabidopsis drought-resistant genes, we detected 34 potential candidates in four species. The expression profile of R. delavayi showed 11 candidate drought-resistant RdMYB genes, which provide a potential molecular design target for breeders. Our results describe the MYB gene family in these four species and could play an important role in future analyses.