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GSE22207
Escherichia coli str. k-12 substr. mg1655
4 Downloadable Samples
Affymetrix E. coli Genome 2.0 Array (ecoli2)
Description
Promoter recognition by bacterial RNA polymerase is mediated by subunits, which assemble transiently to RNA polymerase core enzyme (E) during transcription initiation. subunits drive transcription of specific sets of genes by allowing RNA polymerase to interact with different promoter sequences. However, 70, the housekeeping subunit, and S, an alternative subunit mainly active during slow growth and in response to cellular stresses, appear to recognize almost identical promoter sequences, raising the question of how promoter selectivity is achieved in the bacterial cell. To identify sequence determinants for selective promoter recognition, we performed a run-off/microarray experiment (ROMA): in vitro transcription experiments were carried out with RNA polymerase saturated either with 70 (E70) or with S (ES) using the whole Escherichia coli genome as DNA template, and transcript levels were determined by microarray analysis. We found that several genes associated with bacterial growth (e.g., ribosomal operons) were transcribed more efficiently by E70. In contrast, ES transcribed preferentially genes involved in stress responses, secondary metabolism, as well as regulatory RNAs and intergenic regions with yet unknown function. Genes preferentially recognized in vitro by ES showed reduced expression in ES -deficient mutant strain of E. coli. Sequence comparison of E70- versus ES dependent promoters confirms that the presence of a -35 sequence and the relative location of UP elements affect promoter interaction with either form of RNA polymerase, and suggests that a G/C bias in the -2/+1 nucleotides would favour efficient promoter recognition by E70.
Publication Title
In vitro transcription profiling of the σS subunit of bacterial RNA polymerase: re-definition of the σS regulon and identification of σS-specific promoter sequence elements.
Sample Metadata Fields
Disease
View Samples- Arabidopsis thaliana
- 12 Downloadable Samples
- Affymetrix Arabidopsis ATH1 Genome Array (ath1121501)
Description
Low reduced red:far-red ratio [R:FR] signaling through phytochromes induces shade avoidance responses, including petiole elongation. Jasmonic acid-mediated defense against herbivores and pathogens is inhibited under these conditions.
Publication Title
Low red/far-red ratios reduce Arabidopsis resistance to Botrytis cinerea and jasmonate responses via a COI1-JAZ10-dependent, salicylic acid-independent mechanism.
Sample Metadata Fields
Specimen part, Treatment
View Samples- Arabidopsis thaliana
- 17 Downloadable Samples
- Affymetrix Arabidopsis ATH1 Genome Array (ath1121501)
Description
Selected soil-borne rhizobacteria can trigger an induced systemic resistance (ISR) that is effective against a broad spectrum of pathogens. In Arabidopsis thaliana, the root-specific transcription factor MYB72 is required for the onset of ISR, but is also associated with plant survival under conditions of iron deficiency. Here we investigated the role of MYB72 in both processes. To identify MYB72 target genes, we analyzed the root transcriptomes of wild-type Col-0, mutant myb72, and complemented 35S:FLAG-MYB72/myb72 plants in response to ISR-inducing Pseudomonas fluorescens WCS417. Five WCS417-inducible genes were misregulated in myb72 and complemented in 35S:FLAG-MYB72/myb72. Amongst these, we uncovered -glucosidase BGLU42 as a novel component of the ISR signaling pathway. Overexpression of BGLU42 resulted in constitutive disease resistance, whereas bglu42 was defective in ISR. Furthermore, we found 195 genes to be constitutively upregulated in MYB72-overexpressing roots in the absence of WCS417. Many of these encode enzymes involved in the production of iron-mobilizing phenolic metabolites under conditions of iron deficiency. We provide evidence that BGLU42 is required for their release into the rhizosphere. Together, this work highlights a thus far unidentified link between the ability of beneficial rhizobacteria to stimulate systemic immunity and mechanisms induced by iron deficiency in host plants.
Publication Title
β-Glucosidase BGLU42 is a MYB72-dependent key regulator of rhizobacteria-induced systemic resistance and modulates iron deficiency responses in Arabidopsis roots.
Sample Metadata Fields
Specimen part
View Samples- Mus musculus
- 6 Downloadable Samples
- Affymetrix Mouse Gene 1.0 ST Array (mogene10st)
Description
Akt1, a serine-threonine protein kinase member of the PKB/Akt gene family, plays a critical role in the regulation of several cellular processes including cell proliferation and apoptosis. In this study, we utilized Akt1+/+ and Akt1-/- C57/Bl6 female mice to demonstrate that Akt1 is required for normal mammary gland postnatal development and homeostasis. Akt1 deficiency resulted in severely delayed postnatal mammary gland growth as well as a significant decrease in the number of terminal end buds during puberty. Adult Akt1-/- mammary glands exhibited significantly fewer alveolar buds coupled with a significant increase in epithelial cell apoptosis compared to their wild-type counterparts. Microarray analysis revealed that Akt1 deficiency resulted in several altered gene expression changes and biological processes in adult mammary glands, including organismal development, cell death, and tissue morphology. Of particular importance, a significant decrease in expression of Btn1a1, a gene involved in milk lipid secretion, was observed in Akt1-/- mammary glands by both microarray and RT-PCR validation.
Publication Title
Akt1 is essential for postnatal mammary gland development, function, and the expression of Btn1a1.
Sample Metadata Fields
Sex
View Samples- Homo sapiens
- 32 Downloadable Samples
- Affymetrix Human Gene 1.0 ST Array (hugene10st)
Description
Differences between groups of children with obesity and healthy controls.
Publication Title
Looking for new diagnostic tools and biomarkers of hypertension in obese pediatric patients.
Sample Metadata Fields
Specimen part, Disease
View Samples- Arabidopsis thaliana
- 12 Downloadable Samples
- Affymetrix Arabidopsis ATH1 Genome Array (ath1121501)
Description
Low R:FR signaling through phytochromes induces shade avoidance responses, including petiole elongation. Salicylic acid-mediated defense against pathogens is inhibited under these conditions.
Publication Title
Perception of low red:far-red ratio compromises both salicylic acid- and jasmonic acid-dependent pathogen defences in Arabidopsis.
Sample Metadata Fields
Age, Specimen part, Treatment
View Samples- Drosophila melanogaster
- 2 Downloadable Samples
Illumina HiSeq 2000
Description
We sequenced mRNA extracted from heads of a D. melanogaster population that was sedated with a stream of ethanol saturated vapor, 30 minutes before RNA extraction; and from an age-matched untreated control group. Differential gene expression between the two groups was calculated and reported. Overall design: Examination of mRNA levels in heads of D. melanogaster adult females after ethanol exposure was performed using next generation sequencing (NGS) technology.
Publication Title
Alcohol resistance in Drosophila is modulated by the Toll innate immune pathway.
Sample Metadata Fields
Cell line, Treatment, Subject
View Samples- Danio rerio
- 6 Downloadable Samples
- IlluminaHiSeq4000
Description
RNA sequencing was performed on RNA isolated from groups of 6 hpf wild type and mecp2-null embryos (n=3 biological replicates per condition with 30 embryos pooled per replicate). DESeq2 analysis was performed using https://usegalaxy.org/ Overall design: Whole embryo mRNA profile of 30 pooled mecp2-null or wild type 6 hpf zebrafish embryos, in triplicate, using the Illumina HiSeq4000 platform
Publication Title
Mecp2 regulates <i>tnfa</i> during zebrafish embryonic development and acute inflammation.
Sample Metadata Fields
No sample metadata fields
View Samples- Homo sapiens
- 20 Downloadable Samples
- Affymetrix Human Genome U133 Plus 2.0 Array (hgu133plus2)
Description
To study differentially expressed genes in neuro-ectodermal cell lines
Publication Title
Downregulation of Axl in non-MYCN amplified neuroblastoma cell lines reduces migration.
Sample Metadata Fields
Sex, Specimen part
View Samples- Homo sapiens
- 8 Downloadable Samples
- Affymetrix Human Tiling 2.0R Set, Array 1 (hs35bp01r), Affymetrix Human Gene 1.0 ST Array (hugene10st)
Description
p73 is a p53 family transcription factor that plays critical roles during development and tumor suppression. We analyzed p73 activity using a combination of ChIP-on-Chip and gene expression profiling, both at baseline and after treatment with the mTOR inhibitor rapamycin.
Publication Title
Differential regulation of the p73 cistrome by mammalian target of rapamycin reveals transcriptional programs of mesenchymal differentiation and tumorigenesis.
Sample Metadata Fields
Treatment
View Samples