Gene expression profiling of ElonginA knocked-down Hela cells in the presence of Doxorubicin
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ABSTRACT:
ORGANISM(S): Homo sapiens
PROVIDER: GSE30432 | GEO | 2013/09/03
SECONDARY ACCESSION(S): PRJNA143535
REPOSITORIES: GEO
Similar Datasets
Project description:Transcriptional elongation factor Elongin A exhibits an activity to repress the temporary pause of RNA polymerase II (RNAPII) on the DNA template, resulting in increase of mRNA synthesis in vitro. However, actual elongation ability of Elongin A in mammalian cells has not been determined yet. To elucidate the practical transcriptional role of mammalian Elongin A in vivo, we carried out whole genome expression analysis using Elongin A knocked-down HeLa cells. Gene expression in Elongin A knocked-down HeLa cells was measured at 2 hours after doxorubicin treatment (1microM).
2013-09-03 | E-GEOD-30432 | biostudies-arrayexpress
Project description:Elongin is an RNA polymerase II (RNAPII)-associated factor that has been shown to stimulate transcriptional elongation in vitro. The Elongin complex is thought to be required for transcriptional induction in response to cellular stimuli and to ubiquitinate RNAPII in response to DNA damage. Yet the impact of the Elongin complex on transcription in vivo has not been well studied. Here, we performed comprehensive studies of the role of Elongin A, the largest subunit of the Elongin complex, on RNAPII transcription genome-wide.
In an effort to explore regulatory roles for Elongin A, we performed IP-MS. We constructed a DLD1 cell line expressing Flag-tagged Elongin A at endogenous levels and performed anti-Flag immuno-purification of solubilized chromatin followed by analysis of binding partners by mass spectrometry in triplicates. We identified a large group of Elongin A-associated proteins. We confirmed a subset of possible interacting proteins by Co-IP and western blotting. Consistent with previous studies, we identified RNA Pol II subunits and proteins related to transcription elongation and RNA processing. Among the top hits, we identified nearly all subunits of the PAF1 complex, except for RTF1, which does not stably associate with mammalian PAF1. Concordantly, in our previous PAF1 proteomic study, Elongin A was also among the top hits. We also identified several subunits of the Integrator complex, a multi-subunit complex that has been shown to participate in enhancer RNA (eRNA) processing, a finding consistent with our conclusion that Elongin A localizes to potential enhancers. Collectively, our results suggest that Elongin A stably interacts with RNAPII and the transcription machinery on chromatin.
Taken together, our studies suggest that Elongin A associates with the transcription machinery at actively transcribed genomic regions and may be involved in the release of paused RNAPII. However, Elongin A does not appear to be critical for maintaining transcription elongation rates in vivo.
2020-08-07 | MSV000085926 | MassIVE
Project description:Elongin is a hetero-trimeric elongation factor for RNA polymerase (Pol) II transcription that is conserved among metazoa. We solved three structures of human Elongin bound to transcribing Pol II using cryo-EM assisted by crosslinking mass spectrometry. The structures show that Elongin subunit ELOA binds the RPB2 side of Pol II and anchors the ELOB-8 ELOC subunit heterodimer. ELOA contains an N-terminal ‘latch’ that binds between the end of the RPB1 bridge helix and the funnel helices, thereby inducing a conformational change near the Pol II active center. The latch is strictly required for the elongation-stimulatory activity of Elongin, but not for its binding to Pol II, indicating that Elongin functions by allosterically influencing the conformational mobility of the active center. Structural comparisons show that Elongin binding to Pol II is incompatible with association of super elongation complex, the PAF1 complex, and RTF1, which also contains a latch element that stimulates Pol II.
2023-10-11 | PXD045446 | Pride
Project description:Paused RNA polymerase II that piles up near most human promoters is the target of mechanisms that control entry into productive elongation. Whether paused pol II is a stable or a dynamic target remains unresolved. We report that most 5’-paused pol II throughout the genome is turned over within 2 minutes. This process is revealed under hypertonic conditions that prevent pol II recruitment to promoters. This turnover requires cell viability but is not prevented by inhibiting transcription elongation suggesting that it is mediated at the level of termination. When initiation was prevented by triptolide during recovery from high salt, a novel pre-initiated state of pol II lacking the pausing factor Spt5 accumulated at transcription start sites. We propose that pol II occupancy near 5’ ends is governed by a cycle of ongoing assembly of pre-initiated complexes that transition to pause sites followed by eviction from the DNA template. This model suggests that mechanisms regulating the transition to productive elongation at pause sites operate on a dynamic population of pol II that is turning over at rates far higher than previously suspected. We suggest that a plausible alternative to elongation control via escape from a stable pause, is by escape from premature termination.
2018-09-14 | GSE117006 | GEO
Project description:We have previously shown that RNA polymerase II (Pol II) pause release and transcriptional elongation involve phosphorylation of the factor TRIM28 by the DNA damage response (DDR) kinases ATM and DNA-PK. Here, we report a significant role for DNA breaks and DDR signaling in the mechanisms of transcriptional elongation in stimulus-inducible genes in humans. Our data show the enrichment of TRIM28 and γH2AX on serum-induced genes and the important function of DNA-PK for Pol II pause release and transcriptional activation-coupled DDR signaling on these genes. γH2AX accumulation decreases when P-TEFb is inhibited, confirming that DDR signaling results from transcriptional elongation. In addition, transcriptional elongation-coupled DDR signaling involves topoisomerase II because inhibiting this enzyme interferes with Pol II pause release and γH2AX accumulation. Our findings propose that DDR signaling is required for effective Pol II pause release and transcriptional elongation through a novel mechanism involving TRIM28, DNA-PK, and topoisomerase II 42 samples in total. IP targets were gammaH2ax, s2-pol-II, pol-II, pTRIM28, DNA-pk, topo-IIB. Experimental conditions included DMSO treatment (control), pTEFb, topoII-i, dnapk-i. Matched non-specific IP samples used for control in peak calling.
2015-11-20 | E-GEOD-75170 | biostudies-arrayexpress
Project description:Non-cleaving Cas9 (dCas9) is widely employed to manipulate specific gene loci often with scant regard for unintended transcriptional effects. We demonstrate here that dCas9 mediates precise transcriptional pausing followed by transcription termination and potential alternative polyadenylation. In contrast, alternative splicing is unaffected, likely requiring more sustained alteration to RNA polymerase II elongation speed. The effect on transcription is orientation-specific, with pausing only being induced when dCas9-associated guide RNA anneals to the non-template strand. Targeting template strand induces minimal effects on transcription elongation and thus provides a neutral approach to recruit dCas9 linked effector domains to specific gene regions. In essence we evaluate molecular effects of targeting dCas9 to mammalian transcription units. In so doing we also provide new information on transcriptional elongation by RNA polymerase II and coupled pre-mRNA processing.
2023-05-16 | GSE228798 | GEO
Project description:To identify potential Elongin A targets during neuronal differentiation of ES cells, a cDNA microarray analysis comparing embryoid bodies (EBs) derived from Elongin A+/+ ES cells and Elongin A-/- ES cells was performed. Gene expression in EBs derived from Elongin A+/+ and Elongin A-/- ES cells was measured at day 4 after retinoic acid treatment (2 ?M).
2011-07-25 | E-GEOD-30911 | biostudies-arrayexpress
Project description:We have previously shown that RNA polymerase II (Pol II) pause release and transcriptional elongation involve phosphorylation of the factor TRIM28 by the DNA damage response (DDR) kinases ATM and DNA-PK. Here, we report a significant role for DNA breaks and DDR signaling in the mechanisms of transcriptional elongation in stimulus-inducible genes in humans. Our data show the enrichment of TRIM28 and γH2AX on serum-induced genes and the important function of DNA-PK for Pol II pause release and transcriptional activation-coupled DDR signaling on these genes. γH2AX accumulation decreases when P-TEFb is inhibited, confirming that DDR signaling results from transcriptional elongation. In addition, transcriptional elongation-coupled DDR signaling involves topoisomerase II because inhibiting this enzyme interferes with Pol II pause release and γH2AX accumulation. Our findings propose that DDR signaling is required for effective Pol II pause release and transcriptional elongation through a novel mechanism involving TRIM28, DNA-PK, and topoisomerase II
2015-11-20 | GSE75170 | GEO
Project description:The purpose of this study was to investigate the role of the yeast protein, high mobility group protein (Hmo1), in rRNA synthesis. For over twenty years, Hmo1 has been proposed to be an activator of transcription by Pol I, but its regulatory mechanism remains largely undefined. Therefore, we used native elongating transcript sequencing (NET-seq) to explore the role of this factor in transcription by Pol I. Our NET-seq results demonstrated that in cells lacking Hmo1 (hmo1D), Pol I occupancy was significantly increased across the rDNA template, indicating an increased pause propensity in these cells. These data suggest that Hmo1 is an important transcription elongation factor for Pol I.
2023-11-20 | GSE247981 | GEO
Project description:Gene expression is regulated by controlling distinct steps of the transcriptional cycle, including initiation, pausing, elongation, and termination. Kinases phosphorylate RNA Polymerase II and associated factors to control transitions between these steps and act as central gene regulatory nodes. Similarly, phosphatases that dephosphorylate these components are emerging as important regulators of transcription, though their roles remain less well understood. Here we discover that the PNUTS-PP1 phosphatase complex plays an essential role in controlling transcription pause release in addition to its previously described function in transcription termination. Transcription pause release by the PNUTS complex is essential for almost all RNA Pol II-dependent gene transcription, relies on its PP1 phosphatase subunit, and controls the phosphorylation of factors required for pause release and elongation. Together, this reveals an essential new role for a phosphatase complex in transcription pause release and shows that the PNUTS complex is essential for RNA Poll II-dependent transcription.
2024-06-28 | MSV000095177 | MassIVE