Abstract:G-box-binding protein (GBF), the transcription factors which can recognize and bind to G-box, is widely involved in the regulating gene expression in response to external stimuli. The differentially expressed gene EgrGBF was screened by RNA-seq from primary to secondary growth of Eucalyptus grandis. In order to investigate its function, EgrGBF was cloned from E. grandis, and its structure and evolution were analyzed. The results showed that the length of EgrGBF1 coding region was 984 bp, encoding 327 amino acids. There were two transcripts, named EgrGBF1α and EgrGBF1β. The real-time quantitative PCR showed that expression pattern of EgrGBF1α and EgrGBF1β were different in various tissues and hormones and stress treatments. The expression EgrGBF1α was main in shoot apex, and gradually decreased down the internode, while that of EgrGBF1β was high in phloem, and there was no significant difference among internodes. Meanwhile, the expression trend of EgrGBF1α and EgrGBF1β was opposite treated by salicylic acid and boron deficiency. Under phosphorus deficiency, the expression of EgrGBF1α and EgrGBF1β was the highest at 168 h and 6 h, respectively. Therefore, EgrGBF1 plays an important role in the growth and development of Eucalyptus and the response to stress, and the transcriptional EgrGBF1α and EgrGBF1β may have different functions.
