The human genome contains approximately 27,700 CpG islands (CGIs). Most are associated with promoters and their DNA is nearly always unmethylated. By contrast, CGIs lying within the bodies of genes usually become methylated during differentiation and development. CGIs also normally become methylated at X-inactivated and imprinted genes and abnormally methylated in genome rearrangements and in malignancy. In such circumstances, methylation of CGIs is often associated with RNA transcripts reading through these elements but the relationship of this RNA to methylation of CGIs is not clear. Here we investigated a previously described form of a-thalassemia caused by a genome rearrangement leading to abnormal transcription and DNA methylation of the CGI at the promoter of the a-globin gene. We show that transcription per se is responsible for DNMT3B-mediated methylation of the globin CGI, and that this is a general mechanism responsible for methylation of most intragenic CpG islands. Overall design: CapSeq was performed on day 7 in vitro differentiated EBs containing the human gene sequence of RHBDF1 with (RHBDF1+P; chr16:47,861-63,210, hg18) or without (RHBDF1-P; chr16:47,911-60,819, hg18) its promoter in the a recombination mediated cassette exchange (RMCE) system established within the mouse a-globin locus (Lynch et al., 2012, DOI: 10.1038/emboj.2011.399 ) to map transcription initiation sites within the transgene. Please note that the Cap-seq methods captures the 5' end of any short RNA that was Capped, capturing both coding and non-coding RNA.
DNA methylation of intragenic CpG islands depends on their transcriptional activity during differentiation and disease.
Specimen part, Cell line, Subject
View SamplesTranscriptional changes were monitored in the wheat cultivar Renan 24 hours post i noculation with adapted and non-adapted Magnaporthe isolates using the Affymetrix wheat genome array GeneChip. Wheat plants cv. Renan were grown in a peat and sand (1:1) mix at 23 C in a Sanyo Fitotron growth cabinet (Sanyo Gallenkamp PLC, Loughborough, U.K.) with a 16/8 h, light/dark cycle. Three Magnaporthe isolates were used in this expt, two wheat-adapted isolates (BR32, BR37) and one wheat non-adapted isolate (BR29). Magnaporthe isolates were grown for eleven days on Complete Media Agar at 25 C under a 16/8h, light/dark cycle. Conidia were harvested by flooding the plates with 5 mL of sterile inoculation solution [0.25% (w/v) gelatine and 0.01% (v/v) Tween 20] and scraping the conidia from the surface using a sterile glass rod. Conidia were filtered through sterile miracloth and the density adjusted to 1 x 10 5 conidia mL-1 with inoculation solution. Fourteen day old wheat seedlings mist inoculated with 4 mL of a Magnaporthe conidia suspension and plants were sealed in plastic propagators to maintain relative humidity c.100% and kept at 25 C in the dark for the first 24 hours post inoculation (hpi). Inoculation solution without Magnaporthe conidia was used as a mock-inoculation control. Leaf samples were collected 24 hpi for transcriptomics analysis from three independent biological experiments. Leaf tissue was ground under liquid nitrogen and total RNA extracted using a QIAquick RNeasy Plant Extraction Kit (Qiagen, Hilden, Germany), followed by TURBO DNaseTM (Ambion, Texas, U.S.A.) treatment. RNeasy Mini Spin column purification (Qiagen) was used to further purify RNA samples for array hybridisation. RNA quality checks, cRNA conversion and Affymetrix genome array hybridisation was carried out by the Nottingham Arabidopsis Stock Centre (NASC) array hybridisation service (http://affymetrix.arabidopsis.info/). ****[PLEXdb(http://www.plexdb.org) has submitted this series at GEO on behalf of the original contributor, Graham McGrann. The equivalent experiment is TA24 at PLEXdb.]
Wheat blast: histopathology and transcriptome reprogramming in response to adapted and nonadapted Magnaporthe isolates.
Specimen part, Treatment
View SamplesThis SuperSeries is composed of the SubSeries listed below.
Sleep is not just for the brain: transcriptional responses to sleep in peripheral tissues.
Specimen part, Treatment, Time
View SamplesMolecular profiles in sleep and sleep deprivation in peripheral tissues using microarrays
Sleep is not just for the brain: transcriptional responses to sleep in peripheral tissues.
Specimen part, Treatment, Time
View SamplesMolecular profiles in sleep and sleep deprivation in peripheral tissues using microarrays
Sleep is not just for the brain: transcriptional responses to sleep in peripheral tissues.
Specimen part, Treatment, Time
View SamplesTranscriptional profiles of uropathogenic Escherichia coli CFT073 exposed to cranberry-derived proanthocyanidins (PACs) were determined. Our results indicate that bacteria grown on media supplemented with PACs were iron-deprived. To our knowledge, this is the first time that PACs have been shown to induce a state of iron-limitation in this bacterium.
Induction of a state of iron limitation in uropathogenic Escherichia coli CFT073 by cranberry-derived proanthocyanidins as revealed by microarray analysis.
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View SamplesAlthough the specific functions of sleep have not been completely elucidated, the literature has suggested that sleep is essential for proper homeostasis. Sleep loss is associated with changes in behavioral, neurochemical, cellular, and metabolic function as well as impaired immune response. We evaluated the gene expression profiles of healthy male volunteers who underwent 60 hours of prolonged wakefulness (PW) followed by 12 hours of sleep recovery (SR) using high-resolution microarrays. Peripheral whole blood was collected at 8 am in the morning before the initiation of PW (baseline), after the second night of PW, and one night after SR. We identified over 500 genes that were differentially expressed. Notably, these genes were related to DNA damage and repair and stress response as well diverse immune system responses such as natural killer pathways including killer cell lectin-like receptors family, as well granzymes and T-cell receptors which play important roles in host defense. These results support the idea that sleep loss can lead to alterations in molecular processes that result in perturbation of cellular immunity, induction of inflammatory responses, and homeostatic imbalance. Moreover, expression of multiple genes was down-regulated following PW and up-regulated after SR compared to PW, suggesting an attempt of the body to re-establish internal homeostasis. In silico validation of alterations in the expression of CETN3, DNAJC and CEACAM genes, confirmed previous findings related to the molecular effects of sleep deprivation. Thus, the present findings confirm that the effects of sleep loss are not restricted to the brain and can occur intensely in peripheral tissues.
Whole blood genome-wide gene expression profile in males after prolonged wakefulness and sleep recovery.
Specimen part
View SamplesWe performed RNA sequencing on melanopsin deleted retinas (Opn4-DTA/DTA) to determine potential cues involved in instructing cone photoreceptor positioning Overall design: RNAseq of whole P8 retinal extracts from wild-type littermate vs. Opn4DTA/DTA mice
Melanopsin Retinal Ganglion Cells Regulate Cone Photoreceptor Lamination in the Mouse Retina.
Specimen part, Subject
View SamplesIn this study, we assess the effect of zoledronic acid on clearance of disseminated tumour cells (DTCs) from the bone marrow in women undergoing neoadjuvant chemotherapy for breast cancer
CXCR4 Protein Epitope Mimetic Antagonist POL5551 Disrupts Metastasis and Enhances Chemotherapy Effect in Triple-Negative Breast Cancer.
Specimen part
View Samples