title: Integration of trap- and root-derived nitrogen nutrition of carnivorous Dionaea muscipula.
abstract: Carnivorous Dionaea muscipula operates active snap traps for nutrient acquisition from prey; so what is the role of D. muscipula's reduced root system? We studied the capacity for nitrogen (N) acquisition via traps, and its effect on plant allometry; the capacity of roots to absorb NO₃(-), NH₄(+) and glutamine from the soil solution; and the fate and interaction of foliar- and root-acquired N. Feeding D. muscipula snap traps with insects had little effect on the root : shoot ratio, but promoted petiole relative to trap growth. Large amounts of NH₄(+) and glutamine were absorbed upon root feeding. The high capacity for root N uptake was maintained upon feeding traps with glutamine. High root acquisition of NH₄(+) was mediated by 2.5-fold higher expression of the NH₄(+) transporter DmAMT1 in the roots compared with the traps. Electrophysiological studies confirmed a high constitutive capacity for NH₄(+) uptake by roots. Glutamine feeding of traps inhibited the influx of (15)N from root-absorbed (15)N/(13)C-glutamine into these traps, but not that of (13)C. Apparently, fed traps turned into carbon sinks that even acquired organic carbon from roots. N acquisition at the whole-plant level is fundamentally different in D. muscipula compared with noncarnivorous species, where foliar N influx down-regulates N uptake by roots.
authors.affiliation: Institut für Forstwissenschaften, Professur für Baumphysiologie, Universität Freiburg, Georges-Koehler-Allee 53/54, 79110, Freiburg, Germany.
authors.forename: Peng
authors.initials: P
authors.lastname: Gao
authors.affiliation: Institut für Forstwissenschaften, Professur für Baumphysiologie, Universität Freiburg, Georges-Koehler-Allee 53/54, 79110, Freiburg, Germany.
authors.forename: Theresa Sofi
authors.initials: TS
authors.lastname: Loeffler
authors.affiliation: Institut für Forstwissenschaften, Professur für Baumphysiologie, Universität Freiburg, Georges-Koehler-Allee 53/54, 79110, Freiburg, Germany.
authors.forename: Anne
authors.initials: A
authors.lastname: Honsel
authors.affiliation: Institut für Forstwissenschaften, Professur für Baumphysiologie, Universität Freiburg, Georges-Koehler-Allee 53/54, 79110, Freiburg, Germany.
authors.forename: Jörg
authors.initials: J
authors.lastname: Kruse
authors.affiliation: Institute for Molecular Plant Physiology and Biophysics, University of Würzburg, D-97070, Würzburg, Germany.
authors.forename: Elzbieta
authors.initials: E
authors.lastname: Krol
authors.affiliation: Institute for Molecular Plant Physiology and Biophysics, University of Würzburg, D-97070, Würzburg, Germany.
authors.forename: Sönke
authors.initials: S
authors.lastname: Scherzer
authors.affiliation: Institute for Molecular Plant Physiology and Biophysics, University of Würzburg, D-97070, Würzburg, Germany.
authors.forename: Ines
authors.initials: I
authors.lastname: Kreuzer
authors.affiliation: Institute for Molecular Plant Physiology and Biophysics, University of Würzburg, D-97070, Würzburg, Germany.
authors.forename: Felix
authors.initials: F
authors.lastname: Bemm
authors.affiliation: German Research Center for Environmental Health, Institut für Bodenökologie, Helmholtz Zentrum München, 85764, Neuherberg, Germany.
authors.forename: Franz
authors.initials: F
authors.lastname: Buegger
authors.affiliation: Institut für Forstwissenschaften, Forstzoologisches Institut, Tennenbacher Strasse 4, 79085, Freiburg, Germany.
authors.forename: Tim
authors.initials: T
authors.lastname: Burzlaff
authors.affiliation: Institute for Molecular Plant Physiology and Biophysics, University of Würzburg, D-97070, Würzburg, Germany.
authors.forename: Rainer
authors.initials: R
authors.lastname: Hedrich
authors.affiliation: Institut für Forstwissenschaften, Professur für Baumphysiologie, Universität Freiburg, Georges-Koehler-Allee 53/54, 79110, Freiburg, Germany.
authors.forename: Heinz
authors.initials: H
authors.lastname: Rennenberg
mesh_terms: D064751:Ammonium Compounds / Q000378:metabolism; D000818:Animals; D002247:Carbon Isotopes; D031257:Droseraceae / Q000378:metabolism*; D007313:Insecta; D008969:Molecular Sequence Data; D009584:Nitrogen / Q000378:metabolism*; D009587:Nitrogen Isotopes; D009747:Nutritional Physiological Phenomena; D018515:Plant Leaves / Q000378:metabolism; D010940:Plant Proteins / Q000378:metabolism; D018517:Plant Roots / Q000378:metabolism*; D011235:Predatory Behavior
chemical_list: D064751:Ammonium Compounds; D002247:Carbon Isotopes; D009587:Nitrogen Isotopes; D010940:Plant Proteins; D009584:Nitrogen
keywords: ammonium; glutamine; nitrogen (N) nutrition; plant carnivory; root : shoot integration