title: Comparative genetic analysis of Arabidopsis purple acid phosphatases AtPAP10, AtPAP12, and AtPAP26 provides new insights into their roles in plant adaptation to phosphate deprivation.
abstract: Induction and secretion of acid phosphatases (APases) is thought to be an adaptive mechanism that helps plants survive and grow under phosphate (Pi) deprivation. In Arabidopsis, there are 29 purple acid phosphatase (AtPAP) genes. To systematically investigate the roles of different AtPAPs, we first identified knockout or knock-down T-DNA lines for all 29 AtPAP genes. Using these atpap mutants combined with in-gel and quantitative APase enzyme assays, we demonstrated that AtPAP12 and AtPAP26 are two major intracellular and secreted APases in Arabidopsis while AtPAP10 is mainly a secreted APase. On Pi-deficient (P-) medium or P- medium supplemented with the organophosphates ADP and fructose-6-phosphate (Fru-6-P), growth of atpap10 was significantly reduced whereas growth of atpap12 was only moderately reduced, and growth of atpap26 was nearly equal to that of the wild type (WT). Overexpression of the AtPAP12 or AtPAP26 gene, however, caused plants to grow better on P- or P- medium supplemented with ADP or Fru-6-P. Interestingly, Pi levels are essentially the same for the WT and overexpressing lines, although these two types of plants have significantly different growth phenotypes. These results suggest that the APases may have other roles besides enhancing internal Pi recycling or releasing Pi from external organophosphates for plant uptake.
authors: MOE Key Laboratory of Bioinformatics, Center for Plant Biology, School of Life Sciences, Tsinghua University, Beijing, 100084, China.
authors: Liangsheng
authors: L
authors: Wang
authors: Shan
authors: S
authors: Lu
authors: Ye
authors: Y
authors: Zhang
authors: Zheng
authors: Z
authors: Li
authors: Xiaoqiu
authors: X
authors: Du
authors: Dong
authors: D
authors: Liu
mesh_terms: D000135:Acid Phosphatase / Q000378:metabolism*; D000222:Adaptation, Physiological / Q000187:drug effects / Q000235:genetics; D000814:Aniline Compounds / Q000378:metabolism; D017360:Arabidopsis / Q000201:enzymology* / Q000235:genetics / Q000254:growth & development / Q000502:physiology*; D029681:Arabidopsis Proteins / Q000235:genetics* / Q000378:metabolism*; D018533:Biomass; D017343:Genes, Plant; D006023:Glycoproteins / Q000378:metabolism*; D042541:Intracellular Space / Q000201:enzymology; D009154:Mutation / Q000235:genetics; D009943:Organophosphorus Compounds / Q000378:metabolism; D010641:Phenotype; D010710:Phosphates / Q000172:deficiency* / Q000494:pharmacology; D018517:Plant Roots / Q000187:drug effects / Q000201:enzymology; D018520:Plant Shoots / Q000187:drug effects / Q000201:enzymology; D030821:Plants, Genetically Modified; D036226:Seedlings / Q000187:drug effects / Q000201:enzymology; D013379:Substrate Specificity / Q000187:drug effects
chemical_list: D000814:Aniline Compounds; D029681:Arabidopsis Proteins; D006023:Glycoproteins; D009943:Organophosphorus Compounds; D010710:Phosphates; C068798:4-aminophenylphosphate; C091137:purple acid phosphatase; D000135:Acid Phosphatase
keywords: AtPAP overexpression; Phosphate starvation responses; acid phosphatase activity; atpap mutants; tolerance to phosphate deprivation