Genome-wide identification and characterization of the DREB transcription factor gene family in mulberry

The dehydration responsive element binding (DREB) transcription factor (TF) family comprises unique and important proteins involved in abiotic stress responses and tolerance in plants. Although DREB TFs have been well identified and characterized in a few model plants, there is no detailed information available for mulberry. In this study, 110 AP2/ERF family genes were identified based on a genome-wide analysis of the Morus genome database. Among them, 30 Morus notabilis DREB family genes (MnDREBs) were identified. A comparative analysis with DREB gene families from other plants suggests that MnDREBs could be divided into six subgroups (A-1 to A-6) and could have similar functions in response to abiotic stresses since they have similar conserved domains/motifs within each subgroup. The expression patterns of MnDREBs were analyzed using transcriptome data of different organs from M. notabilis and the quantitative real-time polymerase chain reaction. The expression of most MnDREBs was detected in different organs and induced by various abiotic stresses, which suggest their vital roles in abiotic stress tolerance.