Many genes determining cell identity are regulated by clusters of Mediator-bound enhancer elements collectively referred to as super-enhancers. These super-enhancers have been proposed to manifest higher-order properties important in development and disease. Here we report a comprehensive functional dissection of one of the strongest putative super-enhancers in erythroid cells. By generating a series of mouse models, deleting each of the five regulatory elements of the a-globin super-enhancer individually and in informative combinations, we demonstrate that each constituent enhancer seems to act independently and in an additive fashion with respect to hematological phenotype, gene expression, chromatin structure and chromosome conformation, without clear evidence of synergistic or higher-order effects. Our study highlights the importance of functional genetic analyses for the identification of new concepts in transcriptional regulation. Overall design: Mouse fetal liver erythroid RNA-seq. The RNA of the erythroid cells was metabolically labelled using 4-thiourdine nucleotide analogue supplementation of viable cells in culture. RNA transcripts that incorporated the analogue and hence were synthesised during this period of exposure, were then isolated from the pre-exiting bulk RNA by the addition of a biotin moiety and pull down.
Genetic dissection of the α-globin super-enhancer in vivo.
Specimen part, Subject
View SamplesDuchenne Muscular Dystrophy (DMD) is a fatal muscle wasting disorder caused by dystrophin deficiency. Previous work suggested that increased expression of the dystrophin-related protein utrophin in the mdx mouse model of DMD can prevent dystrophic pathophysiology. Physiological tests showed that the transgenic mouse muscle functioned in a way similar to normal muscle. More recently, it has become possible to analyse disease pathways using microarrays, a sensitive method to evaluate the efficacy of a therapeutic approach. We thus examined the gene expression profile of mdx mouse muscle compared to normal mouse muscle and compared the data with that obtained from the transgenic line expressing utrophin. The data confirm that the expression of utrophin in the mdx mouse muscle results in a gene expression profile virtually identical to that seen for the normal mouse. This study confirms that a strategy to up-regulate utrophin is likely to be effective in preventing the disease.
Microarray analysis of mdx mice expressing high levels of utrophin: therapeutic implications for dystrophin deficiency.
No sample metadata fields
View SamplesSkeletal muscle actin mice (Crawford et al., (2002) Mol Cell Biol 22, 5587) were crossed with cardiac actin transgenic mice (termed "ACTC^Coco" or "Coco" for short), to produce mice that had cardiac actin instead of skeletal muscle actin in their skeletal muscles (termed "ACTC^Co/KO" or for short "Coco/KO"). Microarray analysis using the Illumina mouse-6 v1.1 expression beadchip was performed on RNA extraced from the soleus muscle of Coco/KO mice and wildtype mice, to confirm the swith in actin isoform expression, and to determine what other differences might exist between wildtype mice and the Coco/KO mice.
Rescue of skeletal muscle alpha-actin-null mice by cardiac (fetal) alpha-actin.
No sample metadata fields
View SamplesThis SuperSeries is composed of the SubSeries listed below.
Alignment of time course gene expression data and the classification of developmentally driven genes with hidden Markov models.
No sample metadata fields
View SamplesThe mammalian suprachiasmatic nucleus (SCN) drives daily rhythmic behavior and physiology, yet a detailed understanding of its coordinated transcriptional programmes is lacking. To reveal the true nature of circadian variation in the mammalian SCN transcriptome we combined laser-capture microdissection (LCM) and RNA-Seq over a 24-hour light / dark cycle. We show that 7-times more genes exhibited a classic sinusoidal expression signature than previously observed in the SCN. Another group of 766 genes unexpectedly peaked twice, near both the start and end of the dark phase; this twin-peaking group is significantly enriched for synaptic transmission genes that are crucial for light-induced phase-shifting of the circadian clock. 342 intergenic non-coding RNAs, together with novel exons of annotated protein-coding genes, including Cry1, also show specific circadian expression variation. Overall, our data provide an important chronobiological resource (www.wgpembroke.com/shiny/SCNseq/) and allow us to propose that transcriptional timing in the SCN is gating clock resetting mechanisms. Overall design: Pooled dissected tissue of the suprachiasmatic nucleus from five adult male mice provided one of three replicates for each of six timepoints over a 12:12 light/dark (LD) cycle (ZT2, 6, 10, 14, 18 and 22). Each biological replicate was sequenced over 3 seperate lanes using Illumina HiSeq.
Temporal transcriptomics suggest that twin-peaking genes reset the clock.
Specimen part, Cell line, Subject
View SamplesChanges in gene expression during berry development during a grape growing season were analysed.
Alignment of time course gene expression data and the classification of developmentally driven genes with hidden Markov models.
No sample metadata fields
View SamplesDifferences in gene expression were compared for grape berry flesh and skin.
Alignment of time course gene expression data and the classification of developmentally driven genes with hidden Markov models.
No sample metadata fields
View SamplesAn Arabidopsis mutant showing an altered ability to green on illumination after extended periods of darkness has been isolated in a screen for genomes uncoupled (gun) mutants. Following illumination for 24 h, 10-day-old dark-grown mutant seedlings accumulated 5 times more chlorophyll than wild-type seedlings and this was correlated with differences in plastid morphology observed by transmission electron microscopy. The mutant has been named greening after extended darkness 1 (ged1). We used microarrays to detail the global profiles of transcript abundances in the mutant in comparison to the wild type. Microarray analysis showed much lower amounts of transcripts of genes encoding seed storage proteins, oleosins and late embryogenesis abundant (LEA) proteins in 7-day-old seedlings of ged1 compared to wild type. RNA-gel-blot analyses confirmed very low levels of transcripts of seed protein genes in ged1 seedlings grown for 2-10 days in the dark, and showed higher amounts of transcripts of photosynthesis-related genes in illuminated 10-day-old dark-grown ged1 seedlings compared to wild type.
An Arabidopsis mutant able to green after extended dark periods shows decreased transcripts of seed protein genes and altered sensitivity to abscisic acid.
No sample metadata fields
View SamplesChanges in gene expression on MNV infection of RAW264.7 cells
Murine norovirus replication induces G0/G1 cell cycle arrest in asynchronously growing cells.
Cell line
View SamplesThe MaxiK potassium channel is a key modulator of smooth muscle tone. Due to its calcium and voltage sensitivity, MaxiK is activated following depolarization and Ca2+ mobilization, therefore relaxing the muscle. We investigate the effects of silencing MaxiK for 48h in corpus cavernosuml smooth muscle (CCSM) cells to identify possible mechanisms of compensation through molecular crosstalk between pathways regulating smooth muscle tone.
Silencing MaxiK activity in corporal smooth muscle cells initiates compensatory mechanisms to maintain calcium homeostasis.
Specimen part
View Samples