title: The family of ammonium transporters (AMT) in Sorghum bicolor: two AMT members are induced locally, but not systemically in roots colonized by arbuscular mycorrhizal fungi.
abstract: Arbuscular mycorrhizal (AM) fungi contribute to plant nitrogen (N) acquisition. Recent studies demonstrated the transport of N in the form of ammonium during AM symbiosis. Here, we hypothesize that induction of specific ammonium transporter (AMT) genes in Sorghum bicolor during AM colonization might play a key role in the functionality of the symbiosis. For the first time, combining a split-root experiment and microdissection technology, we were able to assess the precise expression pattern of two AM-inducible AMTs, SbAMT3;1 and SbAMT4. Immunolocalization was used to localize the protein of SbAMT3;1. The expression of SbAMT3;1 and SbAMT4 was greatly induced locally in root cells containing arbuscules and in adjacent cells. However, a split-root experiment revealed that this induction was not systemic. By contrast, a strictly AM-induced phosphate transporter (SbPt11) was expressed systemically in the split-root experiment. However, a gradient of expression was apparent. Immunolocalization analyses demonstrated that SbAMT3;1 was present only in cells containing developing arbuscules. Our results show that the SbAMT3;1 and SbAMT4 genes are expressed in root cortical cells, which makes them ready to accommodate arbuscules, a process of considerable importance in view of the short life span of arbuscules. Additionally, SbAMT3;1 might play an important role in N transfer during AM symbiosis.
authors: Zurich-Basel Plant Science Center, Department of Environmental Sciences, Botany, University of Basel, Hebelstrasse 1, 4056, Basel, Switzerland.
authors: Sally
authors: S
authors: Koegel
authors: UMR INRA 1347/Agrosup/U Bourgogne Agroecology, ERL IPM 6300 CNRS, 17 Rue Sully, BP 86510, 21065, Dijon, France.
authors: Nassima
authors: N
authors: Ait Lahmidi
authors: UMR INRA 1347/Agrosup/U Bourgogne Agroecology, ERL IPM 6300 CNRS, 17 Rue Sully, BP 86510, 21065, Dijon, France.
authors: Christine
authors: C
authors: Arnould
authors: UMR INRA 1347/Agrosup/U Bourgogne Agroecology, ERL IPM 6300 CNRS, 17 Rue Sully, BP 86510, 21065, Dijon, France.
authors: Odile
authors: O
authors: Chatagnier
authors: Zurich-Basel Plant Science Center, Department of Environmental Sciences, Botany, University of Basel, Hebelstrasse 1, 4056, Basel, Switzerland.
authors: Florian
authors: F
authors: Walder
authors: Zurich-Basel Plant Science Center, Department of Environmental Sciences, Botany, University of Basel, Hebelstrasse 1, 4056, Basel, Switzerland.
authors: Kurt
authors: K
authors: Ineichen
authors: Zurich-Basel Plant Science Center, Department of Environmental Sciences, Botany, University of Basel, Hebelstrasse 1, 4056, Basel, Switzerland.
authors: Thomas
authors: T
authors: Boller
authors: UMR INRA 1347/Agrosup/U Bourgogne Agroecology, ERL IPM 6300 CNRS, 17 Rue Sully, BP 86510, 21065, Dijon, France.
authors: Daniel
authors: D
authors: Wipf
authors: Zurich-Basel Plant Science Center, Department of Environmental Sciences, Botany, University of Basel, Hebelstrasse 1, 4056, Basel, Switzerland.
authors: Andres
authors: A
authors: Wiemken
authors: Zurich-Basel Plant Science Center, Department of Environmental Sciences, Botany, University of Basel, Hebelstrasse 1, 4056, Basel, Switzerland.
authors: Pierre-Emmanuel
authors: PE
authors: Courty
mesh_terms: D000595:Amino Acid Sequence; D064751:Ammonium Compounds / Q000493:pharmacokinetics; D027682:Cation Transport Proteins / Q000235:genetics* / Q000378:metabolism; D018506:Gene Expression Regulation, Plant; D005816:Genetic Complementation Test; D042282:Microdissection / Q000379:methods; D008969:Molecular Sequence Data; D005810:Multigene Family; D038821:Mycorrhizae / Q000502:physiology*; D009584:Nitrogen / Q000378:metabolism; D010802:Phylogeny; D010940:Plant Proteins / Q000235:genetics* / Q000378:metabolism; D018517:Plant Roots / Q000235:genetics* / Q000378:metabolism / Q000382:microbiology*; D045868:Sorghum / Q000235:genetics* / Q000378:metabolism / Q000382:microbiology*; D013559:Symbiosis; D015003:Yeasts / Q000235:genetics
chemical_list: D064751:Ammonium Compounds; D027682:Cation Transport Proteins; D010940:Plant Proteins; C088952:ammonium transporters, plant; D009584:Nitrogen