Project description:Arabidopsis wild-type plants (Col-0 accession) were grown on control (+Fe+P) for 7 days on 0.1X MS then transferred to three different medium: control (+Fe+P), iron deficiency (-Fe+P), and iron and phosphate deficiency conditions (-Fe-P). Shoots were collected 39 h, 52 h and 76 h after the transfer. For RNA-seq experiments, three biological replicates were used for each time point (39h, 52h and 76h) and each condition (+Fe+P, -Fe+P and -Fe-P) for a total of 27 samples.
Project description:CsUBC13 was identified via proteomics from iron starvation treated Cucumber root. ubc13A is an ABRC seed stock (CS51269). CS851269 was purchased from ABRC and confirmed as homozygous Atubc13A knock-out T-DNA mutant. We generated transgenic arabidopsis with ectopic expression of CsUBC13 gene under control of the cauliflower 35S promotor. Both genotypes and Col-0 were used to investigate the transcriptional response to Iron (Fe) deficiency. Wild type Col-0, ubc13A and transgenic overexpressor OE were grown under normal and iron-deficiency conditions. Roots were collected with 3 biological replicates.
Project description:Iron (Fe) and copper (Cu) are essential metal micronutrients that are necessary for many redox reactions. The uptake of these metals is tightly regulated in plants. Some redox processes can alternatively use Fe-containing proteins or Cu-containing proteins, depending on nutritional status. Copper deficiency can rescue a Cucumis melo Fe uptake deficient mutant, and Fe deficiency can result in increased accumulation of Cu. However, the system responsible for Fe-deficiency-regulated Cu-uptake is unknown. To understand the genes and gene networks associated with Fe-deficiency regulated Cu uptake and Fe-Cu cross-talk, we conducted transcriptomic profiling of roots and rosettes of spl7 (a Cu uptake deficient mutant in arabidopsis) and Col-0 (WT) grown under Fe, Cu and simultaneous Fe and Cu deficiency conditions.
Project description:Several phytohormones and other small molecules have been demonstrated to be involved in iron (Fe) homeostasis. However, how salicylic acid (SA), an essential hormone in plant immunity and defense responses, participates in Fe-deficiency responses in plants is largely unknown. Here, we took advantage of a SA biosynthesis defect mutant phytoalexin deficient 4 (pad4: T-DNA Salk_089936) to explore the possible effects of endogenous SA on the morphological and physiological responses to Fe deprivation. Under a Fe-deficiency treatment, Col-0 showed more severe leaf chlorosis and root growth inhibition compared with the pad4 mutant. The soluble Fe concentrations were significant higher in pad4 than Col-0 under the Fe-deficiency treatment, suggesting that a mutation in the PAD4 gene may alleviate the Fe-deficiency-induced symptoms by regulating the soluble Fe concentrations. Furthermore, a SA signaling maker line (PR1promoter: GUS) was used to investigate how Fe deficiency affects endogenous SA biosynthesis and metabolism. The data showed that Fe deficiency significantly induced SA accumulation in Col-0, and the loss function of PAD4 blocked this process. The requirement of endogenous SA accumulation for Fe-deficiency responses was confirmed using a series of SA biosynthetic mutants and transgenic lines.
Project description:CsUBC13 was identified via proteomics from iron starvation treated Cucumber root. ubc13A is an ABRC seed stock (CS51269). CS851269 was purchased from ABRC and confirmed as homozygous Atubc13A knock-out T-DNA mutant. We generated transgenic arabidopsis with ectopic expression of CsUBC13 gene under control of the cauliflower 35S promotor. Both genotypes and Col-0 were used to investigate the transcriptional response to Iron (Fe) deficiency.
Project description:Copper and iron are essential micronutrients for most living organisms because they participate as cofactors in biological processes including respiration, photosynthesis and oxidative stress protection. In many eukaryotic organisms, including yeast and mammals, copper and iron homeostases are highly interconnected; however such interdependence is not well established in higher plants. Here we propose that COPT2, a high-affinity copper transport protein, functions under copper and iron deficiencies in Arabidopsis thaliana. COPT2 is a plasma membrane protein that functions in copper acquisition and distribution. Characterization of the COPT2 expression pattern indicates a synergic response to copper and iron limitation in roots. We have characterized a knockout of COPT2, copt2-1, that leads to increased resistance to simultaneous copper and iron deficiencies, measured as reduced leaf chlorosis and improved maintenance of the photosynthetic apparatus. We propose that COPT2 expression could play a dual role under Fe deficiency. First, COPT2 participates in the attenuation of copper deficiency responses driven by iron limitation maybe aimed to minimize further iron consume. On the other hand, global expression analyses of copt2-1 mutants versus wild type Arabidopsis plants indicate that low phosphate responses are increased in copt2-1 plants. In this sense, COPT2 function under Fe deficiency counteracts low phosphate responses. These results open up new biotechnological approaches to fight iron deficiency in crops. Four biological replicates of Arabidopsis seedlings were generated for 2 genotypes, Col-0 and copt2-1 mutant; and 3 growth condictions; first one an iron(Fe) and copper(Cu) sufficient medium (+Fe + Cu), second one an Fe deficient and Cu sufficient medium (-Fe+Cu) and third one an Fe and Cu deficient medium (-Fe-Cu). For each growth one comparasion was made, copt2-1 mutant versus Col-0; in each comparasion four biological replicates were made, two replicas were labeled with Cy5 for the mutant sample and Cy3 for the Col-0 sample, while the other two replicas were reversed-labeled.
Project description:Fe deficiency stimulates a coordinated response involving reduction, transport and redistribution of Fe in the roots. The expression of genes regulated by Fe deficiency in the two contrasting Arabidopsis thaliana ecotypes, Tsu-1 and Kas-1, shows that different ecotypes can respond in diverse ways, with different Fe regulated overrepresented categories. We use microarrays to analyze the Fe deficiency responses of contrasting Arabidopsis thaliana ecotypes (Tsu-1 and Kas-1).
Project description:Iron (Fe) is an essential plant micronutrient, and its deficiency limits plant growth and development on alkaline soils. Under Fe deficiency, plant responses include upregulation of genes involved in Fe uptake from the soil. However, little is known about shoot responses to Fe deficiency. Using microarrays to probe gene expression in Kas-1 and Tsu-1 ecotypes of Arabidopsis thaliana revealed conserved rosette gene expression responses to Fe deficiency. Fe regulated genes included known metal homeostasis-related genes, and a number of genes of unknown function.