Most “dark matter” transcripts are associated with known genes
Ontology highlight
ABSTRACT:
OTHER RELATED OMICS DATASETS IN: GSE19289
PROVIDER: PRJNA120373 | ENA |
REPOSITORIES: ENA
Similar Datasets
Project description:A series of reports over the last few years have indicated that a much larger portion of the mammalian genome is transcribed than can be accounted for by currently annotated genes, but the quantity and nature of these additional transcripts remains unclear. Here, we have used data from single- and paired-end RNA-Seq and tiling arrays to assess the quantity and composition of transcripts in PolyA+ RNA from human and mouse tissues. Relative to tiling arrays, RNA-Seq identifies many fewer transcribed regions (‘‘seqfrags’’) outside known exons and ncRNAs. Most nonexonic seqfrags are in introns, raising the possibility that they are fragments of pre-mRNAs. The chromosomal locations of the majority of intergenic seqfrags in RNA-Seq data are near known genes, consistent with alternative cleavage and polyadenylation site usage, promoter- and terminator-associated transcripts, or new alternative exons; indeed, reads that bridge splice sites identified 4,544 new exons, affecting 3,554 genes. Most of the remaining seqfrags correspond to either single reads that display characteristics of random sampling from a low-level background or several thousand small transcripts (median length = 111 bp) present at higher levels, which also tend to display sequence conservation and originate from regions with open chromatin. We conclude that, while there are bona fide new intergenic transcripts, their number and abundance is generally low in comparison to known exons, and the genome is not as pervasively transcribed as previously reported.
2010-05-18 | GSE19289 | GEO
Project description: Not available
| S-EPMC2872640 | biostudies-literature
Project description:Novel microbial dark matter shaping Shark Bay microbialites
| PRJNA561032 | ENA
Project description:LincRNAs involved in DCS-induced fear extinction: Shedding light on the transcriptomic dark matter
| PRJEB36128 | ENA
Project description:In the unicellular cyanobacterium, Synechococcus elongatus PCC 7942, dramatically reduces the transcription rate in the dark (dark repression), and its cellular functions enormously depend on light as an energy source through photosynthetic activity. Here, we employed high-density oligonucleotide arrays to investigate comprehensive profiles of genome-wide Synechococcus gene expression when illuminated or dark-acclimated cells are treated with photosynthesis inhibitors DCMU or DBMIB. In addition, we added rifampicin to the DBMIB-treated cells in the dark, and analyzed genome-wide expression profiles. Treatment with DCMU or DBMIB under illuminated condition mimicked dark-repression-like genome-wide transcription profiles. Addition of DBMIB under dark condition largely attenuated dark-repression and kept relatively large amount of transcripts, this high-transcripts level still kept when rifampicin was additionally administered.
2015-06-01 | GSE55637 | GEO
Project description:Tissue progenitors maintain the integrity of organ systems through aging and stress. The brain’s white matter regions experience ischemic lesions and age-dependent degeneration. Brain white matter contains progenitors, oligodendrocyte precursor cells (OPCs), which can repair some insults. The response of OPCs to white matter ischemia and aging is not known. We characterized the response of OPCs to white matter stroke using OPC reporter mice, cell migration tracking, OPC specific RNA sequencing, and mechanistic studies in candidate biochemical pathways in the aged brain. White matter stroke induces initial proliferation of local OPCs but blocks differentiation, shunting a portion into astrocytes. Candidate signaling pathways for this differentiation block including novel interactions of inhibin and matrilin-2 and new roles of NgR1 ligands following white matter stroke. Stroke induces inhibin expression in astrocytes and downregulates OPC matrilin-2 that contributes into OPC differentiation block. Antagonism of NgR1 ligands promotes OPC differentiation by attenuating the OPC astrocytic transformation and enhances functional recovery from stroke in aged animals.
2019-11-15 | GSE53737 | GEO
Project description:Chronic alcohol consumption can lead to alchohol-related brain damage (ARBD). Despite the well known acute effects of alcohol the mechanism responsible for chronic brain damage is largely unknown. Pathologically the major change is the loss of white matter while neuronal loss is mild and restricted to a few areas such as the prefrontal cortex. In order to improve our understanding of ARBD pathogenesis we used microarrays to explore the white matter transcriptome of alcoholics and controls. Our results suggest that hepatic encephalopathy, along with two confounders, gray matter contamination and low RNA quality, are major drivers of gene expression in ARBD. All three exceeded the effects of alcohol itself. In particular, low quality RNA samples were characterized by an upregulation of protein translation machinery while hepatic encephalopathy was associated with a downregulation of mitochondrial energy metabolism pathways. The findings in HE alcoholics are consistent with the metabolic acidosis seen in this condition. In contrast non-HE alcoholics had widespread but only subtle changes in gene expression in their white matter. The initial cohort was compromised of four alcoholics without hepatic encephalopathy (non-HE alcoholics), three alcoholics with HE (HE alcoholics) and three neurologically normal controls. For each indvidual frozen white matter was sampled in the superior frontal gyrus (prefrontal cortex) and the precentral gyrus (motor cortex). These two cortices experience either moderate (prefrontal cortex) or no neuronal loss (motor cortex) with alcohol-related brain damage. Each white matter sample was divided in two before RNA was extracted to give two 'biological' repeats and a total of 40 samples. Subsequently eight duplicates were removed due to their gray matter contamination or low RNA quality to leave a 32-sample cohort (23 alcoholic (including eight with HE ) and nine control samples.
2014-01-04 | E-GEOD-53808 | biostudies-arrayexpress
Project description: Not available
| S-EPMC8097831 | biostudies-literature
Project description:Chronic alcohol consumption can lead to alchohol-related brain damage (ARBD). Despite the well known acute effects of alcohol the mechanism responsible for chronic brain damage is largely unknown. Pathologically the major change is the loss of white matter while neuronal loss is mild and restricted to a few areas such as the prefrontal cortex. In order to improve our understanding of ARBD pathogenesis we used microarrays to explore the white matter transcriptome of alcoholics and controls. Our results suggest that hepatic encephalopathy, along with two confounders, gray matter contamination and low RNA quality, are major drivers of gene expression in ARBD. All three exceeded the effects of alcohol itself. In particular, low quality RNA samples were characterized by an upregulation of protein translation machinery while hepatic encephalopathy was associated with a downregulation of mitochondrial energy metabolism pathways. The findings in HE alcoholics are consistent with the metabolic acidosis seen in this condition. In contrast non-HE alcoholics had widespread but only subtle changes in gene expression in their white matter.
2014-01-04 | GSE53808 | GEO
Project description:fapesp-bra-inra-10-01_bioen_hypocotyl - dark hypocotyls tor rnai - Transcriptional comparison between 2 TOR RNAi mutants versus GUS control. - Sowing after 24h imbibition at 4°C in the dark, on MS1/5, no sucrose, 10 mM ethanol, 8 g/l agar, vertical growth with 3h light, 6 days growth in the dark (20°C), hypocotyls were harvested under green light ; cotyledons and root were removed.
2012-10-10 | GSE41404 | GEO