title: Differential Effects of Nitrogen Forms on Cell Wall Phosphorus Remobilization Are Mediated by Nitric Oxide, Pectin Content, and Phosphate Transporter Expression.
abstract: NH4 (+) is a major source of inorganic nitrogen for rice (Oryza sativa), and NH4 (+) is known to stimulate the uptake of phosphorus (P). However, it is unclear whether NH4 (+) can also stimulate P remobilization when rice is grown under P-deficient conditions. In this study, we use the two rice cultivars 'Nipponbare' and 'Kasalath' that differ in their cell wall P reutilization, to demonstrate that NH4 (+) positively regulates the pectin content and activity of pectin methylesterase in root cell walls under -P conditions, thereby remobilizing more P from the cell wall and increasing soluble P in roots and shoots. Interestingly, our results show that more NO (nitric oxide) was produced in the rice root when NH4 (+) was applied as the sole nitrogen source compared with the NO3 (-) The effect of NO on the reutilization of P from the cell walls was further demonstrated through the application of the NO donor SNP (sodium nitroprusside) and c-PTIO (NO scavenger 2-(4-carboxyphenyl)-4, 4, 5, 5-tetramethylimidazoline-1-oxyl-3-oxide). What's more, the P-transporter gene OsPT2 is up-regulated under NH4 (+) supplementation and is therefore involved in the stimulated P remobilization. In conclusion, our data provide novel (to our knowledge) insight into the regulatory mechanism by which NH4 (+) stimulates Pi reutilization in cell walls of rice.
authors.affiliation: State Key Laboratory of Soil and Sustainable Agriculture, China Institute of Soil Science, Chinese Academy of Science, Nanjing 210008, China.
authors.forename: Chun Quan
authors.initials: CQ
authors.lastname: Zhu
authors.affiliation: State Key Laboratory of Soil and Sustainable Agriculture, China Institute of Soil Science, Chinese Academy of Science, Nanjing 210008, China.
authors.forename: Xiao Fang
authors.initials: XF
authors.lastname: Zhu
authors.affiliation: State Key Laboratory of Soil and Sustainable Agriculture, China Institute of Soil Science, Chinese Academy of Science, Nanjing 210008, China.
authors.forename: An Yong
authors.initials: AY
authors.lastname: Hu
authors.affiliation: State Key Laboratory of Soil and Sustainable Agriculture, China Institute of Soil Science, Chinese Academy of Science, Nanjing 210008, China.
authors.forename: Chao
authors.initials: C
authors.lastname: Wang
authors.affiliation: State Key Laboratory of Soil and Sustainable Agriculture, China Institute of Soil Science, Chinese Academy of Science, Nanjing 210008, China.
authors.forename: Bin
authors.identifier: 0000-0001-8103-8673
authors.initials: B
authors.lastname: Wang
authors.affiliation: State Key Laboratory of Soil and Sustainable Agriculture, China Institute of Soil Science, Chinese Academy of Science, Nanjing 210008, China.
authors.forename: Xiao Ying
authors.initials: XY
authors.lastname: Dong
authors.affiliation: State Key Laboratory of Soil and Sustainable Agriculture, China Institute of Soil Science, Chinese Academy of Science, Nanjing 210008, China rfshen@issas.ac.cn.
authors.forename: Ren-Fang
authors.initials: RF
authors.lastname: Shen
mesh_terms: D001565:Benzoates / Q000494:pharmacology; D002265:Carboxylic Ester Hydrolases / Q000378:metabolism; D002473:Cell Wall / Q000187:drug effects / Q000378:metabolism*; D016166:Free Radical Scavengers / Q000494:pharmacology; D018506:Gene Expression Regulation, Plant / Q000187:drug effects*; D007093:Imidazoles / Q000494:pharmacology; D009569:Nitric Oxide / Q000378:metabolism*; D009584:Nitrogen / Q000494:pharmacology*; D012275:Oryza / Q000187:drug effects / Q000235:genetics / Q000378:metabolism; D010368:Pectins / Q000378:metabolism*; D028061:Phosphate Transport Proteins / Q000235:genetics* / Q000378:metabolism; D010758:Phosphorus / Q000378:metabolism*; D010940:Plant Proteins / Q000235:genetics* / Q000378:metabolism; D018517:Plant Roots / Q000187:drug effects / Q000378:metabolism; D012995:Solubility
chemical_list: D001565:Benzoates; D016166:Free Radical Scavengers; D007093:Imidazoles; D028061:Phosphate Transport Proteins; D010940:Plant Proteins; C079393:1,3-dihydroxy-4,4,5,5-tetramethyl-2-(4-carboxyphenyl)tetrahydroimidazole; D010758:Phosphorus; D009569:Nitric Oxide; D010368:Pectins; D002265:Carboxylic Ester Hydrolases; C022323:pectinesterase; D009584:Nitrogen