Cloning and expression of transcription factor gene MrDREBA6 from Malus micromalus.

MrDREB gene is an important family of transcription factors in plant,encoding transcriptional regulators with a variety of functions involved in the developmental and physiological processes.Here,using two degenerate primers according to the sequences of DREB genes from Arabidopsis and rice,a cDNA encoding putative DREB protein was cloned from cDNA of Malus micromalus Makino by RACE,named as MrDREBA6.Then,cDNA and deduced amino acid sequence,phylogenetic tree,function domain and three-dimension structure were predicted and analyzed.MrDREBA6 from Malus micromalus Makino was classified into A6 subgroup of DREB family transcription factor.MrDREBA6,AtRAP2.4 and AtERF1 have similar three-dimension structure.The results of Real-Time-Quantitative PCR analysis for Malus micromalus Makino exposed to various treatments demonstrated that MrDREBA6 gene was induced by PEG,ABA,high-salinity and low-temperature stresses.Expression profiling analyses of MrDREBA6 in different organs indicated that MrDREBA6 gene was mainly expressed in leaf,and faintly expressed in root and stem under normal growth condition.