title: Characterization of purple acid phosphatases involved in extracellular dNTP utilization in Stylosanthes.
abstract: Stylo (Stylosanthes spp.) is a pasture legume predominant in tropical and subtropical areas, where low phosphorus (P) availability is a major constraint for plant growth. Therefore, stylo might exhibit superior utilization of the P pool on acid soils, particularly organic P. However, little is known about mechanisms of inorganic phosphate (Pi) acquisition employed by stylo. In this study, the utilization of extracellular deoxy-ribonucleotide triphosphate (dNTP) and the underlying physiological and molecular mechanisms were examined for two stylo genotypes with contrasting P efficiency. Results showed that the P-efficient genotype, TPRC2001-1, was superior to the P-inefficient genotype, Fine-stem, when using dNTP as the sole P source. This was reflected by a higher dry weight and total P content for TPRC2001-1 than for Fine-stem, which was correlated with higher root-associated acid phosphatase (APase) activities in TPRC2001-1 under low P conditions. Subsequently, three PAP members were cloned from TPRC2001-1: SgPAP7, SgPAP10, and SgPAP26 Expression levels of these three SgPAPs were up-regulated by Pi starvation in stylo roots. Furthermore, there was a higher abundance of transcripts of SgPAP7 and SgPAP10 in TPRC2001-1 than in Fine-stem. Subcellular localization analysis demonstrated that these three SgPAPs were localized on the plasma membrane. Overexpression of these three SgPAPs could result in significantly increased root-associated APase activities, and thus extracellular dNTP utilization in bean hairy roots. Taken together, the results herein suggest that SgPAP7, SgPAP10, and SgPAP26 may differentially contribute to root-associated APase activities, and thus control extracellular dNTP utilization in stylo.
authors.affiliation: College of Agriculture, Hainan University, Institute of Tropical Crop Genetic Resources, Chinese Academy of Tropical Agriculture Sciences, Hainan 570228, P. R. China State Key Laboratory for Conservation and Utilization of Subtropical Agro-bioresources, Root Biology Center, South China Agricultural University, Guangdong 510642, P. R. China.
authors.forename: Pan-Dao
authors.initials: PD
authors.lastname: Liu
authors.affiliation: State Key Laboratory for Conservation and Utilization of Subtropical Agro-bioresources, Root Biology Center, South China Agricultural University, Guangdong 510642, P. R. China.
authors.forename: Ying-Bin
authors.initials: YB
authors.lastname: Xue
authors.affiliation: State Key Laboratory for Conservation and Utilization of Subtropical Agro-bioresources, Root Biology Center, South China Agricultural University, Guangdong 510642, P. R. China.
authors.forename: Zhi-Jian
authors.initials: ZJ
authors.lastname: Chen
authors.affiliation: College of Agriculture, Hainan University, Institute of Tropical Crop Genetic Resources, Chinese Academy of Tropical Agriculture Sciences, Hainan 570228, P. R. China jtian@scau.edu.cn Liuguodao2008@163.com.
authors.forename: Guo-Dao
authors.initials: GD
authors.lastname: Liu
authors.affiliation: State Key Laboratory for Conservation and Utilization of Subtropical Agro-bioresources, Root Biology Center, South China Agricultural University, Guangdong 510642, P. R. China jtian@scau.edu.cn Liuguodao2008@163.com.
authors.forename: Jiang
authors.initials: J
authors.lastname: Tian
mesh_terms: D000135:Acid Phosphatase / Q000235:genetics / Q000378:metabolism* / Q000502:physiology; D003854:Deoxyribonucleotides / Q000378:metabolism*; D007887:Fabaceae / Q000201:enzymology* / Q000235:genetics / Q000378:metabolism; D018506:Gene Expression Regulation, Plant / Q000502:physiology; D005838:Genotype; D006023:Glycoproteins / Q000235:genetics / Q000378:metabolism* / Q000502:physiology; D010802:Phylogeny; D018517:Plant Roots / Q000201:enzymology / Q000378:metabolism
chemical_list: D003854:Deoxyribonucleotides; D006023:Glycoproteins; C091137:purple acid phosphatase; D000135:Acid Phosphatase
keywords: Acid phosphatase activities; Stylosanthes.; dNTP; organic phosphorus; phosphate starvation; purple acid phosphatase