Overexpression of the rice EREBP-like gene OsBIERF3 enhances disease resistance and salt tolerance in transgenic tobacco

The rice OsBIERF3 encodes a protein belonging to the ethylene-responsive element binding protein (EREBP) transcription factor family and was shown to be induced by treatments with chemical inducers of disease resistance response, infection with the blast fungus, Magnaporthe grisea, and by treatments with some abiotic stress conditions, e.g. salt and cold. To better understand the function of OsBIERF3 in disease resistance response and abiotic tolerance, we overexpressed the OsBIERF3 gene in tobacco by Agrobacterium-mediated leaf disc transformation with a construct containing the OsBIERF3 ORF under control of the cauliflower mosaic virus 35S promoter. Disease resistance assays showed that the transgenic tobacco plants enhanced disease resistance against infection by tomato mosaic virus and the bacterial wild fire pathogen, Pseudomonas syringae pv. tabaci. Elevated level of defense-related PR-1a gene expression was also detected in the transgenic tobacco plants. Moreover, the OsBIERF3-overexpressing transgenic tobacco plants also showed increased tolerance to salt stress. Our results suggest that OsBIERF3 may play important roles in disease resistance response and salt tolerance.