Functional Assessment of AtPAP17; Encoding a Purple Acid Phosphatase Involve in Phosphate Metabolism in Arabidopsis thaliana

Abstract PurposePurple acid phosphatases (PAPs) have included the largest classes of non-specific plant acid phosphatases. Most characterized PAPs were found to play physiological functions in phosphorus metabolism. In this study, we investigated the function of AtPAP17 gene encoding an important purple acid phosphatase in A. thaliana.MethodsThe full-length cDNA sequence of AtPAP17 gene under the control of CaMV-35S promoter was transferred to the A. thaliana WT plant. The generated homozygote AtPAP17-overexpressed plants were compared by types of analyses with corresponding homozygote atpap17-mutant plant and WT in both of + P (1.2 mM) and –P (0 mM) conditions.ResultsThe highest and the lowest amount of Pi observed in AtPAP17-overexpressed plants with 111% more and atpap17-mutant plant by 38% less than WT in + P condition, respectively. Furthermore at the same condition, APase activity of AtPAP17-overexpressed plants increased 24% compared to the WT. Inversely, atpap17-mutant plant represented 71% decrease in compared to WT plants. The comparison of fresh weight and dry weight in the studied plants showed that the highest and the lowest amount of absorbed water belonged to OE plants (with 38 and 12 mg plant− 1) and Mu plants (with 22 and 7 mg plant− 1) in + P and –P conditions, respectively.ConclusionThe lack of AtPAP17 gene in the A. thaliana genome led to a remarkable reduction in the development of root biomass. Thus, AtPAP17 could has an important role in the root but not shoot developmental and structural programming. Consequently, this function enables them to absorb more water and eventually associated with more phosphate absorption.