title: A kinetic analysis of cadmium accumulation in a Cd hyper-accumulator fern, Athyrium yokoscense and tobacco plants.
abstract: Cadmium (Cd) accumulations in a Cd hyper-accumulator fern, Athyrium yokoscense (Ay), and tobacco, Nicotiana tabacum (Nt), were kinetically analysed using the positron-emitting tracer imaging system under two medium conditions (basal and no-nutrient). In Ay, maximumly 50% and 15% of the total Cd accumulated in the distal roots and the shoots under the basal condition, respectively. Interestingly, a portion of the Cd in the distal roots returned to the medium. In comparison with Ay, a little fewer Cd accumulations in the distal roots and clearly higher Cd migration to the shoots were observed in Nt under the basal condition (maximumly 40% and 70% of the total Cd, respectively). The no-nutrient condition down-regulated the Cd migration in both species, although the regulation was highly stricter in Ay than in Nt (almost no migration in Ay and around 20% migration in Nt). In addition, the present work enabled to estimate physical and physiological Cd accumulation capacities in the distal roots, and demonstrated condition-dependent changes especially in Ay. These results clearly suggested occurrences of species-/condition-specific regulations in each observed parts. It is probable that integration of these properties govern the specific Cd tolerance/accumulation in Ay and Nt.
authors.affiliation: Plant Molecular Biology, Laboratory for Environmental Science, Central Research Institute of Electric Power Industry, 1646 Abiko, Abiko, 270-1194, Japan; Plant Molecular Biology, Molecular Genetics, Department of Biological Science and Technology, Tokyo University of Science, 2641 Yamazaki, Noda, 278-8510, Japan.
authors.forename: Toshihiro
authors.initials: T
authors.lastname: Yoshihara
authors.forename: Nobuo
authors.initials: N
authors.lastname: Suzui
authors.forename: Satomi
authors.initials: S
authors.lastname: Ishii
authors.forename: Mayu
authors.initials: M
authors.lastname: Kitazaki
authors.forename: Haruaki
authors.initials: H
authors.lastname: Yamazaki
authors.forename: Kazuyoshi
authors.initials: K
authors.lastname: Kitazaki
authors.forename: Naoki
authors.initials: N
authors.lastname: Kawachi
authors.forename: Yong-Gen
authors.initials: YG
authors.lastname: Yin
authors.forename: Sayuri
authors.initials: S
authors.lastname: Ito-Tanabata
authors.forename: Shin-nosuke
authors.initials: SN
authors.lastname: Hashida
authors.forename: Kazuhiro
authors.initials: K
authors.lastname: Shoji
authors.forename: Hiroaki
authors.initials: H
authors.lastname: Shimada
authors.forename: Fumiyuki
authors.initials: F
authors.lastname: Goto
authors.forename: Shu
authors.initials: S
authors.lastname: Fujimaki
mesh_terms: D001345:Autoradiography; D002104:Cadmium / Q000378:metabolism*; D004583:Electrons; D029624:Ferns / Q000378:metabolism*; D021621:Imaging, Three-Dimensional; D007700:Kinetics; D018517:Plant Roots / Q000378:metabolism; D014026:Nicotiana / Q000254:growth & development / Q000378:metabolism*
chemical_list: D002104:Cadmium
keywords: Nicotiana tabacum; PETIS; tolerance