Summary The hyperaccumulation of zinc (Zn) and cadmium (Cd) is a constitutive property the metallophyte Arabidopsis halleri . We therefore used GeneChips to identify genes more active in roots A. as compared thaliana under control conditions. two showing highest expression relative out than 8000 present on chip encode nicotianamine (NA) synthase putative Zn 2+ uptake system. significantly higher activity these other involved metal homeostasis various growth conditions was confirmed by...

ABSTRACT Toxic effects of both essential and non‐essential heavy metals are well documented in plants. Very little is known, however, about their modes toxicity, tolerance mechanisms the signalling cascades involved mediating transcriptional responses to toxic metal excess. We analysed transcriptome changes upon Cd 2+ Cu exposure roots Arabidopsis thaliana ‐hypertolerant metallophyte halleri . Particularly, three categories genes were identified with help this comparative approach: (1)...

ZIP transporters (ZRT, IRT-like proteins) are involved in the transport of iron (Fe), zinc (Zn) and other divalent metal cations. The expression IRT3, a transporter, is higher Zn/cadmium (Cd) hyperaccumulator Arabidopsis halleri than that its ortholog thaliana, which implies positive association with Zn accumulation A. halleri. IRT3 genes from both thaliana functionally complemented uptake mutant Spzrt1 Schizosaccharomyces pombe; double zrt1zrt2, Fe-uptake fet3fet4 conferred Fe activity...

Iron is essential for photosynthesis and often a limiting nutrient plant productivity. Plants respond to conditions of iron deficiency by increasing transcript abundance key genes involved in homeostasis, but only few regulators these have been identified. Using genome-wide expression analysis, we searched transcription factors that are induced within 24 hours after transferring plants iron-deficient growth conditions. Out nearly 100 shown be up-regulated, identified MYB10 MYB72 as the most...

Nonessential metal ions such as cadmium are most likely transported across plant membranes via transporters for essential cations. To identify possible pathways Cd 2+ transport we tested putative cation uptake activity by expressing cDNAs in Saccharomyces cerevisiae and found that expression of one clone, LCT1 , renders the growth yeast more sensitive to cadmium. Ion flux assays showed sensitivity is correlated with an increase uptake. -dependent saturable, lies high-affinity range (apparent...

Abstract The synthesis of phytochelatins (PCs) is essential for the detoxification nonessential metals and metalloids such as cadmium arsenic in plants a variety other organisms. To our knowledge, no direct evidence role PCs metal homeostasis has been reported to date. Prompted by observations Schizosaccharomyces pombe Saccharomyces cerevisiae indicating contribution PC synthase expression Zn2+ sequestration, we investigated known PC-deficient Arabidopsis (Arabidopsis thaliana) mutant,...

Zn deficiency is among the leading health risk factors in developing countries. Breeding of Zn-enriched crops expected to be facilitated by molecular dissection plant hyperaccumulation (i.e., ability certain plants accumulate levels >100-fold higher than normal plants). The model hyperaccumulators Arabidopsis halleri and Noccaea caerulescens share elevated nicotianamine synthase (NAS) expression relative nonaccumulators a core alterations metal homeostasis. Suppression Ah-NAS2 RNA...

Cadmium is a major environmental pollutant that enters human food via accumulation in crop plants. Responses of plants to cadmium exposure—which directly influence rates—are not well understood. In general, little known about stress-elicited changes at the proteome level. Alterations root hydroponically grown Arabidopsis thaliana treated with 10 μM Cd2+ for 24 h are reported here. These conditions trigger synthesis phytochelatins (PCs), glutathione-derived metal-binding peptides, shown here...

Large-scale metabolic profiling is expected to develop into an integral part of functional genomics and systems biology. The metabolome a cell or organism chemically highly complex. Therefore, comprehensive biochemical phenotyping requires multitude analytical techniques. Here, we describe approach that combines separation by capillary liquid chromatography with the high resolution, sensitivity, mass accuracy quadrupole time-of-flight spectrometry. About 2000 different signals can be...

Summary Leaf mineral composition, the leaf ionome, reflects complex interaction between a plant and its environment including local soil an influential factor that can limit species distribution productivity. Here we addressed within‐species variation in plant–soil interactions edaphic adaptation using Arabidopsis halleri , well‐suited model as facultative metallophyte metal hyperaccumulator. We conducted multi‐element analysis of 1972 paired samples from 165 European populations A. at...

Abstract Metabolomics is facing a major challenge: the lack of knowledge about metabolites present in given biological system. Thus, large-scale discovery considered an essential step toward better understanding plant metabolism. We show here that application metabolomics approach generating structural information for analysis Arabidopsis (Arabidopsis thaliana) mutants allows efficient cataloging metabolites. Fifty-six percent features showed significant differences abundance between seeds...

Nicotiana tabacum (tobacco) plants have short and long glandular trichomes. There is evidence that tobacco trichomes play several roles in the defense against biotic abiotic stresses. cDNA libraries were constructed from control cadmium (Cd)-treated leaf Almost 2,000 expressed sequence tag (EST) clones sequenced to analyze gene expression Cd-treated Genes for stress response as well primary metabolism scored highly, indicating trichome a biologically active stress-responsive tissue. Reverse...

Silicon (Si) modulates tolerance to abiotic stresses, but little is known about the reversibility of stress effects by supplementing previously stressed plants with Si. This surprising since recovery experiments might allow mechanisms Si-mediated amelioration be addressed. Rice was exposed 10 µM CdCl2 for 4 d in hydroponics, followed 0.6mM Si(OH)4 supplementation d. Si reversed Cd, as reflected plant growth, photosynthesis, elemental composition, and some biochemical parameters. Cd-dependent...

Fe deficiency compromises both human health and plant productivity. Thus, it is important to understand acquisition strategies for the development of crop plants which are more Fe-efficient under Fe-limited conditions, such as alkaline soils, have higher density in their edible tissues. Root secretion phenolic compounds has long been hypothesized be a component reduction strategy non-graminaceous plants. We therefore subjected roots Arabidopsis thaliana grown Fe-replete Fe-deplete conditions...