Abstract
Plant and crop production are influenced by water accessibility, nutrition supplement and temperature fluctuation. To cope with environmental challenges, a huge set of genes is transcriptionally activated. Many proteins accumulated under dehydration and/or low-temperature conditions, there are also at the same time such as the group 2 LEA protein dehydrin. The mungbean (Vigna radiata) dehydrin VrDHN was isolated previously by our laboratory members. The VrDHN mRNA level was found to increase remarkably when the turgor potential of plant reaches 0.10 MPa. In this study the promoter of the VrDHN gene was isolated and characterized. To characterized the promoter activity, a series of constructs containing different promoter regions fused to the β-glucuronidase (GUS) reporter gene were transiently and stably transformed then subject to histochemical and fluorometric assays. Through transient assay and histochemical and fluorometric assays. The results from transient assay showed that the VrDHN promoter processes about 1/10 activity of the CaMV35S promoted. Analysis of the transgenic Arabidpsis plants indicated the VrDHN promoter is activated at 6 DAP then the activity in seeds after maturation. The VrDHN promoter activity diminished soon after germination. Deletion analysis showed that the −998 to −843 region is important to repress the VrDHN expression.