Copper-regulated genes of Bradyrhizobium japonicum
Ontology highlight
ABSTRACT:
ORGANISM(S): Bradyrhizobium japonicum
SUBMITTER: Hans-Martin Fischer
PROVIDER: E-GEOD-40437 | biostudies-arrayexpress |
REPOSITORIES: biostudies-arrayexpress
Similar Datasets
Project description:Copper-limiting growth conditions were thought to cause an induction of genes possibly involved in copper uptake and sorting. This rationale in mind, we performed microarray analyses on B. japonicum cells grown in three variations of the BVM minimal medium. Variant 1 contained 2 μM CuSO4 (copper excess). Variant 2 was prepared in HCl-treated glassware without any copper added (copper starvation). The residual copper concentration in this copper-starvation medium was analyzed by GF-AAS and determined to be 5 nM. Variant 3 (extreme copper limitation) was prepared like variant 2 but with the addition of 10 μM BCS and 1 mM ascorbic acid where BCS chelates Cu(I) selectively, and ascorbic acid reduces any Cu(II) to Cu(I). Changes in the transcription profiles were recorded by the pairwise comparison of cells grown in variant 2 vs. 1, and variant 3 vs. 2. Only a small set of genes were differentially up- or down-regulated when copper-starved cells were compared with cells grown in copper excess. Most notably, five genes located adjacent to each other on the B. japonicum genome displayed an increased expression: bll4882 to bll4878. The five genes were named pcuA, pcuB, pcuC, pcuD, and pcuE (mnemonic of proteins for Cu trafficking). The genes with decreased expression are either of unknown function or – not surprisingly – play a role in copper resistance. Extreme copper limitation (variant 3 vs. 2) did not further enhance the expression of the five pcu genes. Instead, another cluster of adjacent genes was strongly up-regulated: bll0889 to bll0883, which code for unidentified transport functions. Incidentally, the list also includes the copper chaperone ScoI. Taken together, copper-limiting growth conditions have led to the de-repression of genes potentially involved in copper acquisition.
2012-10-01 | GSE40437 | GEO
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.
2018-03-01 | GSE104916 | GEO
Project description:In Saccharomyces cerevisiae, copper ions regulate gene expression through the two transcriptional activators, Ace1 and Mac1. Ace1 mediates Cu-induced gene expression in cells exposed to stressful levels of copper salts, whereas Mac1 activates a subset of genes under copper-deficient conditions. DNA microarray hybridization experiments revealed a limited set of yeast genes differentially expressed under growth conditions of excess copper or copper deficiency. Mac1 activates the expression of six S. cerevisiae genes, including CTR1, CTR3, FRE1, FRE7, YJL217w and YFR055w. Two of the last three newly identified Mac1 target genes have no known function, the third, YFR055w, is homologous to cystathionine gamma-lyase encoded by CYS3. Several genes that are differentially expressed in cells containing a constitutively active Mac1, designated Mac1up1, are not direct targets of Mac1. Induction or repression of these genes is likely a secondary effect of cells due to constitutive Mac1 activity. Elevated copper levels induced the expression of the metallothioneins CUP1 and CRS5, and two genes, FET3 and FTR1, in the iron uptake system. Cu-induced FET3 and FTR1 expression arises from an indirect Cu effect on cellular Fe pools. This study is described in more detail in Gross C et al.(2000) J Biol Chem 275:32310-6 Keywords: other
2002-02-12 | GSE26 | GEO
Project description:We examined the whole-genome transcriptional response of E. faecalis wild-type (WT) and copy mutant cells exposed to non toxic Cu excess. The analysis was focused in those genes which changed significantly their expression levels in the Cu-treated cells when compared to their untreated counterparts. The results indicated that after 3 h at 0.5 mM CuSO4, WT cells exhibited a significant increment of Cu content and the induction of three genes of cop operon along with other 142 genes. The comparison with the copY mutant exposed to Cu showed an extensive overlapping of transcriptional changes suggesting that other transcription factors may be mediating the response to Cu. Associated manuscript The global response of Enterococcus faecalis to copper exposure
2011-02-14 | GSE20453 | GEO
Project description:Zinc is an essential nutrient because of its role in catalysis and in stabilizing protein structure, but excess zinc can also be deleterious. Four nutritional zinc states have been identified in the alga Chlamydomonas reinhardtii: zinc toxic, zinc replete, zinc deficient and zinc limited. Growth is inhibited in zinc-limited and zinc toxic cells relative to zinc-replete cells, while zinc-deficiency is visually asymptomatic but distinguished by the accumulation of transcripts encoding ZIP family transporters. To identify targets of zinc deficiency and mechanisms of zinc acclimation, we used RNA-seq to probe zinc nutrition responsive changes in gene expression. We identified a subset of genes encoding zinc-handling components, including ZIP family transporters and candidate zinc chaperones. In addition, we noted an impact on two other regulatory pathways, the carbon concentrating mechanism (CCM) and the nutritional copper regulon. Targets of transcription factor Ccm1 and various CAH genes are up-regulated in zinc-deficiency, as a likely consequence of reduced carbonic anhydrase activity, which is validated by mass spectrometry and immunoblot analysis of Cah1, Cah3 and Cah4. Chlamydomonas is therefore not able to grow photoautotrophically in air in zinc limiting conditions, but supplementation with 1% CO2 restores growth to wild-type rates, suggesting that the inability to maintain CCM is a major consequence of zinc limitation. Surprisingly, we noted also that the Crr1 regulon, which responds to Cu limitation, is also turned on in zinc deficiency, and in fact, Crr1 is required for growth in zinc-limiting conditions. Zinc deficient cells are functionally copper deficient, as evidenced by reduced plastocyanin abundance, even though they hyperaccumulate copper up to 50-fold over normal levels. We suggest that zinc-deficient cells sequester Cu in a bio-unavailable form, perhaps to prevent mis-metallation of critical zinc sites. Zn-limited wild-type cells were generated by transfer of cells from the first round of growth in medium with no supplemental Zn into TAP medium supplemented or not with 2.5 µM Zn-EDTA The control samples for this study are represented in GSE25622
2013-05-03 | E-GEOD-41096 | biostudies-arrayexpress
Project description:Higher plants have developed sophisticated mechanisms to efficiently acquire and use micronutrients such as copper and iron. In the present work, we studied effects produced by the presence of a wide copper range in growth media and altered copper transport on iron homeostasis in Oryza sativa plants. The global analysis of gene expression in the rice seedlings grown under copper deficiency versus excess in the medium showed an increased expression of the genes involved in iron homeostasis. Different iron-related genes are expressed under either copper deficiency and excess, such as those that encode ferredoxin and transcriptional regulator IRON-RELATED TRANSCRIPTION FACTOR 2 (OsIRO2), respectively. As expected, the expression of OsCOPT1, which encodes a high affinity copper transport protein, was up-regulated under copper deficiency, and the expression of OsIRO2 targets were increased under copper excess. Arabidopsis COPT1 overexpression (C1OE) in rice causes root shortening under copper excess, modifies the expression of the putative Fe-sensing factor HEMERYTHRIN MOTIF-CONTAINING REALLY INTERESTING NEW GENE- AND ZINC-FINGER (OsHRZ1) and enhances the expression of OsIRO2 and its targets, which suggests a role of copper in iron signaling. Our studies conducted under simultaneous copper and iron deficiencies indicate that C1OE plants are more sensitive than the wild-type controls to root growth inhibition. The C1OE rice plants grown on soil contained higher endogenous iron concentration in grains than the wild-type plants (both brown and white grains). The results obtained herein showed the interaction between homeostatic networks of iron and copper, and suggest that strategies to obtain crops with optimized nutrient concentrations in edible parts should take into account this interaction.
2017-06-20 | GSE89109 | GEO
Project description:This pilot clinical trial studies copper Cu 64 (64Cu) tetra-azacyclododecanetetra-acetic acid (DOTA)-trastuzumab positron emission tomography (PET)/computed tomography (CT) in studying patients with gastric, or stomach cancer. Diagnostic procedures, such as copper Cu 64-DOTA-trastuzumab PET/CT, may help doctors study the characteristics of tumors and choose the best treatment.
| 2151356 | ecrin-mdr-crc
Project description:The transition metal copper (Cu) is an essential element for all living organisms. In plants, Cu plays key roles in electron transport chains of chloroplasts and mitochondria, as well as in cell wall metabolism, ethylene perception, molybdenum cofactor synthesis and oxidative stress protection. Because of its physiological importance, suboptimal concentrations of Cu trigger a re-organization of metabolism to economize on Cu, and pronounced Cu deficiency causes severe growth reduction and defects in male fertility. However, when present in excess, Cu can be highly toxic. Therefore, Cu uptake, utilization and cellular concentrations are strictly regulated. A number of components of the Cu-homeostatic network of Arabidopsis have already been identified. However, the mechanisms that control responses of plant gene expression to Cu-deficiency are only partly understood. In Chlamydomonas reinhardtii, the transcription factor Crr1 is required for activating and/or repressing the expression of a number of genes in response to Cu deficiency. This protein contains a plant-specific DNA-binding domain (SBP domain), ankyrin repeats and a C-terminal cysteine-rich region with similarity to a Drosophila metallothionein (MT). In Arabidopsis, there is a family of 16 proteins with SBP domains named SPL family (SBP-like) of which a subset of proteins have been implicated in flowering time control and floral development. Among all of them, AtSPL7 is the most similar to Crr1 (27 % identity), and AtSPL1 (25 % identity), AtSPL12 (24 % identity) and AtSPL14 (23 % identity) share a common protein architecture. The goal of this work was to obtain a complete account of the response of the Arabidopsis thaliana transcriptome to Cu deficiency, as well as to determine the role of AtSPL7 in the transcriptional response to Cu deficiency. For this purpose, three independent experiments were carried out including Col-0 wild-type and spl7-2 mutant plants grown in Cu-sufficient and Cu-deficient hydroponic media, respectively. Root and shoot transcriptomes were established by RNA-Seq for quantitative comparisons. Sampling of root and shoot tissues of wild-type (WT, Col-0) and spl7-2 mutant plants (the mutant is knock-down for the transcription factor SPL7, which plays a key role in the transcriptional regulation of the copper deficiency responses) cultivated hydroponically in a modified Hoagland's solution under Cu-sufficient (control) and Cu-deficient conditions.
2013-10-14 | E-GEOD-24696 | biostudies-arrayexpress
Project description:The host restricts Mycobacterium tuberculosis (Mtb) access of transition metal ions to inhibit its growth. Cu is essential for the survival of Mtb, but Cu excess is toxic. During co-evolution, Mtb has developed various mechanisms to maintain copper homeostasis. In this report, we firstly found Mtb Rv0102 encoded membrane protein is critical for Mycobacterium Cu uptake. The intracellular Cu level of M. smegmatis (Ms) Rv0102 homolog MSMEG_4702 knockout strain decreased threefold than the wild type, the deletion mutant was more tolerant to higher Cu level. This indicates that Rv0102 is significant for Cu homeostasis and resistance to Cu toxicity. Knocking out the homologous gene MMAR_0267 in M. marinum (Mm) also enhanced its virulence in zebrafish and improved its survival within macrophages. In THP-1 cells infected with Mm, Mm MMAR_0267 deletion mutants’ intracellular survival increased fourfolds and accompanied by less cell apoptosis. Cu deficiency down-regulates the transcription of the M. marinum virulence factor CFP-10, dampening the STING cytosolic signaling in macrophages, fewer IFN-β and less cell apoptosis. These results suggest that Cu is an important factor in inducing cell apoptosis. In summary, mycobacteria can effectively counteract the host's early key nutritional immune mechanisms by regulating copper metabolism, to increase its virulence.
2023-06-30 | GSE235754 | GEO
Project description:In an approach to generate Saccharomyces cerevisiae strains with increased intracellular copper amounts for technical applications we over-expressed the copper transporter CTR1 and a variant of CTR1 with a truncation in the C-terminus after the 300 amino acids (CTR1 delta-300). We determined the copper sensitivity of the generated strains and used inductively coupled plasma spectrometry (ICP-OES and ICP-MS) analysis to investigate the effects of over-expression of both constructs under excess copper on the cellular content of different elements in S. cerevisiae. In addition, we ran DNA microarray analysis to obtain the gene expression profile under the changed element contents. Over-expression of CTR1 increased the copper content in the cells up to 160% and 78 genes were differentially regulated. Over-expression of the truncated CTR1 delta-300 resulted in an increased copper, iron and zinc content of more than 200% and 980 genes showed differential expression. We found that transition metal ion homeostasis was disrupted in CTR1 delta-300 over-expressing strains under excess copper and that this was combined with a transcriptional remodelling of cellular processes Transcription profiling was performed in Saccharomyces cerevisiae BY4741 (referred to as wild type) over-expressing CTR1 and in the ctr1- deletion strain BY4741 delta-ctr1 overexpressing CTR1 delta-300 after 7 hours of culture under excess copper (0.02 mM CuCl2). Control strains contained the corresponding empty vector. Three independent experiments were performed and 12 samples were analyzed.
2014-01-28 | E-GEOD-44043 | biostudies-arrayexpress