title: Nitrogen Use Efficiency Is Mediated by Vacuolar Nitrate Sequestration Capacity in Roots of Brassica napus.
abstract: Enhancing nitrogen use efficiency (NUE) in crop plants is an important breeding target to reduce excessive use of chemical fertilizers, with substantial benefits to farmers and the environment. In Arabidopsis (Arabidopsis thaliana), allocation of more NO3 (-) to shoots was associated with higher NUE; however, the commonality of this process across plant species have not been sufficiently studied. Two Brassica napus genotypes were identified with high and low NUE. We found that activities of V-ATPase and V-PPase, the two tonoplast proton-pumps, were significantly lower in roots of the high-NUE genotype (Xiangyou15) than in the low-NUE genotype (814); and consequently, less vacuolar NO3 (-) was retained in roots of Xiangyou15. Moreover, NO3 (-) concentration in xylem sap, [(15)N] shoot:root (S:R) and [NO3 (-)] S:R ratios were significantly higher in Xiangyou15. BnNRT1.5 expression was higher in roots of Xiangyou15 compared with 814, while BnNRT1.8 expression was lower. In both B. napus treated with proton pump inhibitors or Arabidopsis mutants impaired in proton pump activity, vacuolar sequestration capacity (VSC) of NO3 (-) in roots substantially decreased. Expression of NRT1.5 was up-regulated, but NRT1.8 was down-regulated, driving greater NO3 (-) long-distance transport from roots to shoots. NUE in Arabidopsis mutants impaired in proton pumps was also significantly higher than in the wild type col-0. Taken together, these data suggest that decrease in VSC of NO3 (-) in roots will enhance transport to shoot and essentially contribute to higher NUE by promoting NO3 (-) allocation to aerial parts, likely through coordinated regulation of NRT1.5 and NRT1.8.
authors.affiliation: Southern Regional Collaborative Innovation Center for Grain and Oil Crops in China, Hunan Agricultural University, Changsha, 410128, China (Y.-L.H., H.-X.S., Q.Liao, Y.Y., S.-F.J., Q.Liu, X.-M.R., C.T., J.Z., C.-Y.G., Z.-H.Z.);National Center of Oilseed Crops Improvement, Hunan Branch, Changsha, 410128, China (C.-Y.G.); Center for Environmental Diagnostics and Bioremediation, University of West Florida, Pensacola, Florida 32514, (J.E.L.); andCrop and Environment Sciences Division, International Rice Research Institute, DAPO 7777, Metro Manila, Philippines (A.M.I.).
authors.forename: Yong-Liang
authors.initials: YL
authors.lastname: Han
authors.affiliation: Southern Regional Collaborative Innovation Center for Grain and Oil Crops in China, Hunan Agricultural University, Changsha, 410128, China (Y.-L.H., H.-X.S., Q.Liao, Y.Y., S.-F.J., Q.Liu, X.-M.R., C.T., J.Z., C.-Y.G., Z.-H.Z.);National Center of Oilseed Crops Improvement, Hunan Branch, Changsha, 410128, China (C.-Y.G.); Center for Environmental Diagnostics and Bioremediation, University of West Florida, Pensacola, Florida 32514, (J.E.L.); andCrop and Environment Sciences Division, International Rice Research Institute, DAPO 7777, Metro Manila, Philippines (A.M.I.).
authors.forename: Hai-Xing
authors.initials: HX
authors.lastname: Song
authors.affiliation: Southern Regional Collaborative Innovation Center for Grain and Oil Crops in China, Hunan Agricultural University, Changsha, 410128, China (Y.-L.H., H.-X.S., Q.Liao, Y.Y., S.-F.J., Q.Liu, X.-M.R., C.T., J.Z., C.-Y.G., Z.-H.Z.);National Center of Oilseed Crops Improvement, Hunan Branch, Changsha, 410128, China (C.-Y.G.); Center for Environmental Diagnostics and Bioremediation, University of West Florida, Pensacola, Florida 32514, (J.E.L.); andCrop and Environment Sciences Division, International Rice Research Institute, DAPO 7777, Metro Manila, Philippines (A.M.I.).
authors.forename: Qiong
authors.initials: Q
authors.lastname: Liao
authors.affiliation: Southern Regional Collaborative Innovation Center for Grain and Oil Crops in China, Hunan Agricultural University, Changsha, 410128, China (Y.-L.H., H.-X.S., Q.Liao, Y.Y., S.-F.J., Q.Liu, X.-M.R., C.T., J.Z., C.-Y.G., Z.-H.Z.);National Center of Oilseed Crops Improvement, Hunan Branch, Changsha, 410128, China (C.-Y.G.); Center for Environmental Diagnostics and Bioremediation, University of West Florida, Pensacola, Florida 32514, (J.E.L.); andCrop and Environment Sciences Division, International Rice Research Institute, DAPO 7777, Metro Manila, Philippines (A.M.I.).
authors.forename: Yin
authors.initials: Y
authors.lastname: Yu
authors.affiliation: Southern Regional Collaborative Innovation Center for Grain and Oil Crops in China, Hunan Agricultural University, Changsha, 410128, China (Y.-L.H., H.-X.S., Q.Liao, Y.Y., S.-F.J., Q.Liu, X.-M.R., C.T., J.Z., C.-Y.G., Z.-H.Z.);National Center of Oilseed Crops Improvement, Hunan Branch, Changsha, 410128, China (C.-Y.G.); Center for Environmental Diagnostics and Bioremediation, University of West Florida, Pensacola, Florida 32514, (J.E.L.); andCrop and Environment Sciences Division, International Rice Research Institute, DAPO 7777, Metro Manila, Philippines (A.M.I.).
authors.forename: Shao-Fen
authors.identifier: http://orcid.org/0000-0002-7553-642X
authors.initials: SF
authors.lastname: Jian
authors.affiliation: Southern Regional Collaborative Innovation Center for Grain and Oil Crops in China, Hunan Agricultural University, Changsha, 410128, China (Y.-L.H., H.-X.S., Q.Liao, Y.Y., S.-F.J., Q.Liu, X.-M.R., C.T., J.Z., C.-Y.G., Z.-H.Z.);National Center of Oilseed Crops Improvement, Hunan Branch, Changsha, 410128, China (C.-Y.G.); Center for Environmental Diagnostics and Bioremediation, University of West Florida, Pensacola, Florida 32514, (J.E.L.); andCrop and Environment Sciences Division, International Rice Research Institute, DAPO 7777, Metro Manila, Philippines (A.M.I.).
authors.forename: Joe Eugene
authors.initials: JE
authors.lastname: Lepo
authors.affiliation: Southern Regional Collaborative Innovation Center for Grain and Oil Crops in China, Hunan Agricultural University, Changsha, 410128, China (Y.-L.H., H.-X.S., Q.Liao, Y.Y., S.-F.J., Q.Liu, X.-M.R., C.T., J.Z., C.-Y.G., Z.-H.Z.);National Center of Oilseed Crops Improvement, Hunan Branch, Changsha, 410128, China (C.-Y.G.); Center for Environmental Diagnostics and Bioremediation, University of West Florida, Pensacola, Florida 32514, (J.E.L.); andCrop and Environment Sciences Division, International Rice Research Institute, DAPO 7777, Metro Manila, Philippines (A.M.I.).
authors.forename: Qiang
authors.initials: Q
authors.lastname: Liu
authors.affiliation: Southern Regional Collaborative Innovation Center for Grain and Oil Crops in China, Hunan Agricultural University, Changsha, 410128, China (Y.-L.H., H.-X.S., Q.Liao, Y.Y., S.-F.J., Q.Liu, X.-M.R., C.T., J.Z., C.-Y.G., Z.-H.Z.);National Center of Oilseed Crops Improvement, Hunan Branch, Changsha, 410128, China (C.-Y.G.); Center for Environmental Diagnostics and Bioremediation, University of West Florida, Pensacola, Florida 32514, (J.E.L.); andCrop and Environment Sciences Division, International Rice Research Institute, DAPO 7777, Metro Manila, Philippines (A.M.I.).
authors.forename: Xiang-Min
authors.initials: XM
authors.lastname: Rong
authors.affiliation: Southern Regional Collaborative Innovation Center for Grain and Oil Crops in China, Hunan Agricultural University, Changsha, 410128, China (Y.-L.H., H.-X.S., Q.Liao, Y.Y., S.-F.J., Q.Liu, X.-M.R., C.T., J.Z., C.-Y.G., Z.-H.Z.);National Center of Oilseed Crops Improvement, Hunan Branch, Changsha, 410128, China (C.-Y.G.); Center for Environmental Diagnostics and Bioremediation, University of West Florida, Pensacola, Florida 32514, (J.E.L.); andCrop and Environment Sciences Division, International Rice Research Institute, DAPO 7777, Metro Manila, Philippines (A.M.I.).
authors.forename: Chang
authors.initials: C
authors.lastname: Tian
authors.affiliation: Southern Regional Collaborative Innovation Center for Grain and Oil Crops in China, Hunan Agricultural University, Changsha, 410128, China (Y.-L.H., H.-X.S., Q.Liao, Y.Y., S.-F.J., Q.Liu, X.-M.R., C.T., J.Z., C.-Y.G., Z.-H.Z.);National Center of Oilseed Crops Improvement, Hunan Branch, Changsha, 410128, China (C.-Y.G.); Center for Environmental Diagnostics and Bioremediation, University of West Florida, Pensacola, Florida 32514, (J.E.L.); andCrop and Environment Sciences Division, International Rice Research Institute, DAPO 7777, Metro Manila, Philippines (A.M.I.).
authors.forename: Jing
authors.initials: J
authors.lastname: Zeng
authors.affiliation: Southern Regional Collaborative Innovation Center for Grain and Oil Crops in China, Hunan Agricultural University, Changsha, 410128, China (Y.-L.H., H.-X.S., Q.Liao, Y.Y., S.-F.J., Q.Liu, X.-M.R., C.T., J.Z., C.-Y.G., Z.-H.Z.);National Center of Oilseed Crops Improvement, Hunan Branch, Changsha, 410128, China (C.-Y.G.); Center for Environmental Diagnostics and Bioremediation, University of West Florida, Pensacola, Florida 32514, (J.E.L.); andCrop and Environment Sciences Division, International Rice Research Institute, DAPO 7777, Metro Manila, Philippines (A.M.I.).
authors.forename: Chun-Yun
authors.initials: CY
authors.lastname: Guan
authors.affiliation: Southern Regional Collaborative Innovation Center for Grain and Oil Crops in China, Hunan Agricultural University, Changsha, 410128, China (Y.-L.H., H.-X.S., Q.Liao, Y.Y., S.-F.J., Q.Liu, X.-M.R., C.T., J.Z., C.-Y.G., Z.-H.Z.);National Center of Oilseed Crops Improvement, Hunan Branch, Changsha, 410128, China (C.-Y.G.); Center for Environmental Diagnostics and Bioremediation, University of West Florida, Pensacola, Florida 32514, (J.E.L.); andCrop and Environment Sciences Division, International Rice Research Institute, DAPO 7777, Metro Manila, Philippines (A.M.I.).
authors.forename: Abdelbagi M
authors.identifier: http://orcid.org/0000-0002-1961-3072
authors.initials: AM
authors.lastname: Ismail
authors.affiliation: Southern Regional Collaborative Innovation Center for Grain and Oil Crops in China, Hunan Agricultural University, Changsha, 410128, China (Y.-L.H., H.-X.S., Q.Liao, Y.Y., S.-F.J., Q.Liu, X.-M.R., C.T., J.Z., C.-Y.G., Z.-H.Z.);National Center of Oilseed Crops Improvement, Hunan Branch, Changsha, 410128, China (C.-Y.G.); Center for Environmental Diagnostics and Bioremediation, University of West Florida, Pensacola, Florida 32514, (J.E.L.); andCrop and Environment Sciences Division, International Rice Research Institute, DAPO 7777, Metro Manila, Philippines (A.M.I.) zhzh1468@163.com.
authors.forename: Zhen-Hua
authors.initials: ZH
authors.lastname: Zhang
mesh_terms: D027321:Anion Transport Proteins / Q000235:genetics / Q000378:metabolism; D017360:Arabidopsis / Q000235:genetics / Q000378:metabolism; D001692:Biological Transport / Q000187:drug effects / Q000235:genetics; D029688:Brassica napus / Q000145:classification / Q000235:genetics / Q000378:metabolism*; D004024:Dicyclohexylcarbodiimide / Q000494:pharmacology; D018506:Gene Expression Regulation, Plant; D005838:Genotype; D043564:Inorganic Pyrophosphatase / Q000037:antagonists & inhibitors / Q000235:genetics / Q000378:metabolism; D018942:Macrolides / Q000494:pharmacology; D009154:Mutation; D009566:Nitrates / Q000378:metabolism*; D009584:Nitrogen / Q000378:metabolism*; D010940:Plant Proteins / Q000235:genetics / Q000378:metabolism; D018517:Plant Roots / Q000235:genetics / Q000378:metabolism*; D018520:Plant Shoots / Q000235:genetics / Q000378:metabolism; D020133:Reverse Transcriptase Polymerase Chain Reaction; D013045:Species Specificity; D025262:Vacuolar Proton-Translocating ATPases / Q000037:antagonists & inhibitors / Q000235:genetics / Q000378:metabolism; D014617:Vacuoles / Q000235:genetics / Q000378:metabolism*; D052584:Xylem / Q000235:genetics / Q000378:metabolism
chemical_list: D027321:Anion Transport Proteins; D018942:Macrolides; D009566:Nitrates; D010940:Plant Proteins; D004024:Dicyclohexylcarbodiimide; C040929:bafilomycin A1; D025262:Vacuolar Proton-Translocating ATPases; D043564:Inorganic Pyrophosphatase; D009584:Nitrogen