Histochemical localization of GUS expression
GUS histochemical staining was performed using a GUS staining kit (SL7160,Coolaber). The ProBnA09PHT5;1b:GUS andProBnCnPHT5;1b:GUS transgenic plants were grown in a standard 1/2 MS nutrient solution for 5 days and then transferred to 100 µM and 1,000 µM Pi conditions for 5 days. The whole plants submerged in GUS staining solution were incubated in the dark at 37℃ for 8 hrs. After staining, the tissues were washed with 75% ethanol to remove chlorophyll and imaged by microscope (SMZ25,Nikon).