Functional Study Of The BpMYB108 Gene Associated With Drought And Salt Tolerance In Arabidopsis Thaliana

MYB(avian myeloblastosis)is one of the largest family of transcription factors.MYB transcription factors play important roles in mediating of growth processes and responses to signaling molecules and environmental factors in plants.In previous study,a R2R3 MYB transcription factor,named as BpMYB108,was revealed by searching in the transcriptome database of birch.Analyzing of its expression pattern showed that the Bp MYB 108 gene may be associate with response to salt stress.In this study,the expression patterns and the functional characterization of the BpMYB108 were investigated.The main results are as follows:1.The BplMYB108 was fused with GFP protein tagging,the transient transformation in tobacco leaf shows that BpMYB108 was located on the nuclear2.The spatial-temporal expression profiles show that BpMYB108 gene expressed in root,stem and leaf,respectively.The expression analyses of BpMYB108 in root under salt,drought,ABA stresses indicated that BpMYB108 was strongly induced by salt and drought as well as ABA stress regulators,indicating that the BpMYB108 gene was involved in stress response.3.The promoter fragment of BpMYB108 with 1622bp in length was cloned,and bioinformatic analysis revealed that it harbors numerous cis-regulatory elements associated with abiotic stress and signaling molecules etc.The BpMYB108 promoter was then analyzed for its ability to control the expression of the GUS reporter gene in transgenic tobacco plants.BpMYB108-GUS expression was strongly induced by the plant stress regulators in the transformed tobacco plants.4.The full-length BpMYB108 gene was cloned into the overexpression vector and transformed into Arabidopsis genome by the floral dip method.The transgenic Arabidopsis plants under NaCl and mannitol treatments showed better performance than those of nontransgenic controls in terms of the physiological and growth features.This analysis indicated that overexpression BpMYB108 gene could improve the ability of salt and drought tolerance in Arabidopsis thaliana plants.