Divergent transcription from active promoters
Ontology highlight
ABSTRACT:
ORGANISM(S): Homo sapiens
PROVIDER: GSE13483 | GEO | 2008/11/06
SECONDARY ACCESSION(S): PRJNA110161
REPOSITORIES: GEO
Similar Datasets
Project description:Here we describe a novel class of short RNAs that indicate widespread divergent transcription at mammalian promoters Small RNA cloning and deep sequencing from human embryonic stem cells, derived neural progenitors and neurons
2008-11-06 | E-GEOD-13483 | biostudies-arrayexpress
Project description:Here we describe a novel class of short RNAs and high-resolution ChIP-Seq data that together indicate widespread divergent transcription at mammalian promoters and suggest the existence of novel regulatory mechanisms concerning both initiation and elongation by RNA polymerase II. ChIP-seq in murine embryonic stem cells for RNA polymerase II
2008-12-01 | E-GEOD-12680 | biostudies-arrayexpress
Project description:Here we describe a novel class of short RNAs and high-resolution ChIP-Seq data that together indicate widespread divergent transcription at mammalian promoters and suggest the existence of novel regulatory mechanisms concerning both initiation and elongation by RNA polymerase II.
2008-12-01 | GSE12680 | GEO
Project description:Our ability to understand the control logic embedded in the human genome is limited by a lack of accurate information of the promoter sequences for most genes. Promoters are a unique class of control sequences, serving as the binding sites for both sequence-specific factors and the general transcription machinery during transcription initiation. In order to obtain a comprehensive map of promoters in the human genome, we have determined the location of the RNA polymerase II preinitiation complex throughout the non-repeat sequences of the human genome in primary fibroblast cells. The resulting map defines 10,571 active promoters corresponding to 6,763 known genes and at least 1,199 un-annotated transcriptional units. The map indicates extensive usage of multiple promoters by the human genes and widespread clustering of active promoters in the genome. Further examination of the genome-wide expression profile reveals four general classes of promoters that define the transcriptome of the cell. Our results provide a global view of the functional relationship among the transcriptional machinery, chromatin structure, and gene expression in human cells. Keywords = GALA Keywords = gene expression Keywords = nimblegen Keywords = promoter profile Keywords = LICR renlab Keywords: other
2010-07-01 | E-GEOD-2672 | biostudies-arrayexpress
Project description:In mammalian cells, widespread acceleration of cytoplasmic mRNA degradation is linked to impaired RNA polymerase II (Pol II) transcription. This mRNA decay-induced transcriptional repression occurs during infection with gammaherpesviruses including Kaposi’s sarcoma associated herpesvirus (KSHV) and murine gammaherpesvirus 68 (MHV68), which encode an mRNA endonuclease that initiates widespread RNA decay. Here, we show that MHV68-induced mRNA decay leads to a genome-wide reduction of Pol II occupancy at mammalian promoters. Viral genes, despite the fact that they require Pol II for transcription, escape this transcriptional repression. Protection is not governed by viral promoter sequences; instead, location on the viral genome is both necessary and sufficient to escape the transcriptional repression effects of mRNA decay. We hypothesize that the ability to escape from transcriptional repression is linked to the localization of viral DNA in replication compartments, providing a means for these viruses to counteract decay-induced viral transcript loss.
2019-12-10 | PXD015786 | Pride
Project description:Anthracyclines are a class of widely prescribed anti-cancer drugs that disrupt chromatin by intercalating into DNA and enhancing nucleosome turnover. To understand the molecular consequences of anthracycline-mediated chromatin disruption, we utilized CUT&Tag to profile RNA polymerase II during anthracycline treatment in Drosophila cells. We observed that treatment with the anthracycline aclarubicin leads to elevated levels of elongating RNA polymerase II and changes in chromatin accessibility. We found that promoter proximity and orientation impacts chromatin changes during aclarubicin treatment, as closely spaced divergent promoter pairs show greater chromatin changes when compared to codirectionally-oriented tandem promoters. We also found that aclarubicin treatment changes the distribution of non-canonical DNA G-quadruplex structures both at promoters and at G-rich pericentromeric repeats. Our work suggests that aclarubicin's anti-cancer activity is driven by the effects of nucleosome disruption on RNA polymerase II, chromatin accessibility and DNA structures.
2023-05-04 | GSE221252 | GEO
Project description:The directionality of gene promoters, the proportion of protein coding over divergent noncoding transcription, is highly variable and regulated. How promoter directionality is controlled remains poorly understood. We show that chromatin remodelling complex RSC, general regulatory factors (GRFs) including transcription factors (TFs) can facilitate promoter directionality by attenuating divergent noncoding transcription. Depletion of RSC increased divergent noncoding and decreased protein coding transcription of promoters with strong directionality. Consistent with RSC’s role in regulating chromatin, RSC depletion negatively impacts nucleosome positions upstream of the nucleosome depleted region where divergent transcription initiates, suggesting that nucleosome positioning upstream in promoters physically blocks the recruitment of transcription machinery. Likewise, divergent transcription can be suppressed by targeting GRFs and TFs or the bulky dCas9 protein to transcriptional initiation sites. We propose that RSC mediated nucleosome positioning, GRFs including TFs form the physical barriers in promoters for limiting of divergent transcription, thereby controlling promoter directionality.
2021-07-27 | GSE179254 | GEO
Project description:Transcription initiation by RNA polymerase II (RNAPII) is thought to occur unidirectionally from most genes. Here, we present evidence of widespread divergent transcription at protein-encoding gene promoters. Transcription start site-associated RNAs (TSSa-RNAs) nonrandomly flank active promoters, with peaks of antisense and sense short RNAs at 250 nucleotides upstream and 50 nucleotides downstream of TSSs, respectively. Northern analysis shows that TSSa-RNAs are subsets of an RNA population 20 to 90 nucleotides in length. Promoter-associated RNAPII and H3K4-trimethylated histones, transcription initiation hallmarks, colocalize at sense and antisense TSSa-RNA positions; however, H3K79-dimethylated histones, characteristic of elongating RNAPII, are only present downstream of TSSs. These results suggest that divergent transcription over short distances is common for active promoters and may help promoter regions maintain a state poised for subsequent regulation.
| S-EPMC2692996 | biostudies-literature
Project description:The directionality of gene promoters, the proportion of protein coding over divergent noncoding transcription, is highly variable and regulated. How promoter directionality is controlled remains poorly understood. We show that chromatin remodelling complex RSC, general regulatory factors (GRFs) including transcription factors (TFs) can facilitate promoter directionality by attenuating divergent noncoding transcription. Depletion of RSC increased divergent noncoding and decreased protein coding transcription of promoters with strong directionality. Consistent with RSC’s role in regulating chromatin, RSC depletion negatively impacts nucleosome positions upstream of the nucleosome depleted region where divergent transcription initiates, suggesting that nucleosome positioning upstream in promoters physically blocks the recruitment of transcription machinery. Likewise, divergent transcription can be suppressed by targeting GRFs and TFs or the bulky dCas9 protein to transcriptional initiation sites. We propose that RSC mediated nucleosome positioning, GRFs including TFs form the physical barriers in promoters for limiting of divergent transcription, thereby controlling promoter directionality.
2021-07-27 | GSE179255 | GEO
Project description:Mammalian transcriptomes are complex and formed by extensive promoter activity. Moreover, gene promoters are largely divergent and initiate transcription of reverse-oriented promoter upstream transcripts (PROMPTs). Although PROMPTs are commonly terminated early, influenced by early polyadenylation (pA) sites, promoters often cluster so that the divergent activity of one might impact another. Here, we find that the distance between promoters strongly correlates with the expression, stability and length of their associated PROMPTs. Adjacent promoters driving divergent mRNA transcription support PROMPT formation, but due to pA site constraints, these transcripts tend to spread into the neighboring mRNA on the same strand. This mechanism to derive new alternative mRNA transcription start sites (TSSs) is also evident at closely spaced promoters supporting convergent mRNA transcription. We suggest that basic building blocks of divergently transcribed core promoter pairs, in combination with the wealth of TSSs in mammalian genomes, provides a framework with which evolution shapes transcriptomes. Mapping of paired 5â?? and 3â??ends of capped and polyadenylated RNAs from RRP40-depleted and eGFP control HeLa cells and using transcript isoform sequencing (TIF-Seq, see Pelechano et al. Nat Protoc 2014 (PMID: 24967623) and Pelechano et al. Nature 2013 (PMID: 23615609)).
2016-05-13 | E-GEOD-75183 | biostudies-arrayexpress