title: Elemental concentrations in the seed of mutants and natural variants of Arabidopsis thaliana grown under varying soil conditions.
abstract: The concentrations of mineral nutrients in seeds are critical to both the life cycle of plants as well as human nutrition. These concentrations are strongly influenced by soil conditions, as shown here by quantifying the concentration of 14 elements in seeds from Arabidopsis thaliana plants grown under four different soil conditions: standard, or modified with NaCl, heavy metals, or alkali. Each of the modified soils resulted in a unique change to the seed ionome (the mineral nutrient content of the seeds). To help identify the genetic networks regulating the seed ionome, changes in elemental concentrations were evaluated using mutants corresponding to 760 genes as well as 10 naturally occurring accessions. The frequency of ionomic phenotypes supports an estimate that as much as 11% of the A. thaliana genome encodes proteins of functional relevance to ion homeostasis in seeds. A subset of mutants were analyzed with two independent alleles, providing five examples of genes important for regulation of the seed ionome: SOS2, ABH1, CCC, At3g14280 and CNGC2. In a comparison of nine different accessions to a Col-0 reference, eight accessions were observed to have reproducible differences in elemental concentrations, seven of which were dependent on specific soil conditions. These results indicate that the A. thaliana seed ionome is distinct from the vegetative ionome, and that elemental analysis is a sensitive approach to identify genes controlling ion homeostasis, including those that regulate gene expression, phospho-regulation, and ion transport.
authors.affiliation: Department of Biochemistry and Molecular Biology, University of Nevada, Reno, Nevada, United States of America.
authors.forename: Stephen C
authors.initials: SC
authors.lastname: McDowell
authors.forename: Garo
authors.initials: G
authors.lastname: Akmakjian
authors.forename: Chris
authors.initials: C
authors.lastname: Sladek
authors.forename: David
authors.initials: D
authors.lastname: Mendoza-Cozatl
authors.forename: Joe B
authors.initials: JB
authors.lastname: Morrissey
authors.forename: Nick
authors.initials: N
authors.lastname: Saini
authors.forename: Ron
authors.initials: R
authors.lastname: Mittler
authors.forename: Ivan
authors.initials: I
authors.lastname: Baxter
authors.forename: David E
authors.initials: DE
authors.lastname: Salt
authors.forename: John M
authors.initials: JM
authors.lastname: Ward
authors.forename: Julian I
authors.initials: JI
authors.lastname: Schroeder
authors.forename: Mary Lou
authors.initials: ML
authors.lastname: Guerinot
authors.forename: Jeffrey F
authors.initials: JF
authors.lastname: Harper
mesh_terms: D017360:Arabidopsis / Q000235:genetics / Q000254:growth & development / Q000378:metabolism*; D029681:Arabidopsis Proteins / Q000235:genetics; D027682:Cation Transport Proteins / Q000235:genetics; D054815:Cyclic Nucleotide-Gated Cation Channels / Q000235:genetics; D009154:Mutation; D010641:Phenotype; D017346:Protein Serine-Threonine Kinases / Q000235:genetics; D039381:RNA Cap-Binding Proteins / Q000235:genetics; D012639:Seeds / Q000235:genetics / Q000254:growth & development / Q000378:metabolism*; D012987:Soil / Q000737:chemistry*; D014131:Trace Elements / Q000378:metabolism*
chemical_list: D029681:Arabidopsis Proteins; D027682:Cation Transport Proteins; D054815:Cyclic Nucleotide-Gated Cation Channels; D017346:Protein Serine-Threonine Kinases; D039381:RNA Cap-Binding Proteins; D012987:Soil; D014131:Trace Elements; C435105:At2g13540 protein, Arabidopsis; C518228:CNGC2 protein, Arabidopsis; C406738:SOS2 protein, Arabidopsis