Abstract
It is well known that vacuole has various functions for inorganic metabolisms in plant cell. Although vacuolar membrane proteins must be playing important roles for this, molecular works of those proteins are quite limited.
In the previous study we have succeeded in isolating highly purified tonoplast from Arabidopsis cultured cells and conducted the proteome analysis of membrane-bound proteins by LC-MS/MS. We identified certain unannotated transmembrane proteins besides the major tonoplast proteins. In order to find phosphate metabolism-related proteins, we selected possible candidates having phosphate responsible specific sequences in promoter regions and analyzed them in detail. At first to confirm the subcellular distribution of these proteins, we transformed GFP fusion proteins transiently to Arabidopsis cultured cells. To analyze the function of these proteins, we constructed transgenic BY-2 cells which overexpressed these proteins or GFP fusion proteins. We are measuring physiological responses of these cells to several phosphate conditions.
