title: High-affinity nitrate uptake by rice (Oryza sativa) coleoptiles.
abstract: Nitrate uptake by rice coleoptiles was evaluated using ¹⁵N-nitrate in relation to the expression of high-affinity nitrate uptake-related genes, OsNRT2s (OsNRT2.1-2.4) and OsNAR2s (OsNAR2.1 and 2.2). Apparent nitrate uptake by coleoptiles was about one-sixth of that by hydroponically cultured seedling roots. Real-time RT-PCR analysis revealed that OsNRT2.1, a root-specific key gene of inducible high-affinity transport system for nitrate, was most strongly induced in coleoptiles following nitrate supply initiation, while other OsNRT2s and OsNAR2s showed modest induction. These results suggest that rice coleoptiles may have high-affinity transport systems for nitrate similar to roots, and can be model organs for nutrient uptake by submerged plant shoots.
authors.affiliation: Graduate School of Environmental Science, University of Shiga Prefecture, 2500 Hassaka-cho, Hikone, Shiga 522-8533, Japan.
authors.forename: Shu
authors.initials: S
authors.lastname: Takayanagi
authors.forename: Yuma
authors.initials: Y
authors.lastname: Takagi
authors.forename: Ryoichi
authors.initials: R
authors.lastname: Araki
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Hasegawa
mesh_terms: D027321:Anion Transport Proteins / Q000187:drug effects / Q000235:genetics / Q000378:metabolism; D001692:Biological Transport; D018548:Cotyledon / Q000187:drug effects / Q000235:genetics / Q000378:metabolism; D018506:Gene Expression Regulation, Plant / Q000187:drug effects; D000091285:Nitrate Transporters; D009566:Nitrates / Q000378:metabolism*; D012275:Oryza / Q000187:drug effects / Q000235:genetics / Q000378:metabolism*; D010940:Plant Proteins / Q000187:drug effects / Q000235:genetics / Q000378:metabolism*; D018517:Plant Roots / Q000187:drug effects / Q000235:genetics / Q000378:metabolism; D018749:RNA, Plant / Q000235:genetics; D060888:Real-Time Polymerase Chain Reaction; D013997:Time Factors
chemical_list: D027321:Anion Transport Proteins; D000091285:Nitrate Transporters; D009566:Nitrates; D010940:Plant Proteins; D018749:RNA, Plant