Global Analysis of the Drosophila NELF complex
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ABSTRACT:
ORGANISM(S): Drosophila melanogaster
PROVIDER: GSE6141 | GEO | 2008/07/14
SECONDARY ACCESSION(S): PRJNA97699
REPOSITORIES: GEO
Similar Datasets
Project description:To determine the physiological targets of the NELF complex, and provide insight into the mechanism of NELF activity in vivo. Experiment Overall Design: Drosophila melanogaster S2 cells, obtained from the Drosophila Genomics Resource Center, were untreated, or treated with dsRNA for 72 hours, as described in Armknecht, S. et al. (2005) Methods in Enzymology, 392: pp. 55-73. Total RNA was then extracted using the RNeasy RNA extraction kit, with on column DNAse digestion (Qiagen), according to manufacturerâs protocol. Gene expression analysis was conducted using Drosophila Genome 2.0 Genechip® arrays (Affymetrix, Santa Clara, CA). Starting with 1ug of total RNA, biotin-labeled cRNA was produced using the Affymetrix 3â Amplification One-Cycle Target labeling kit according to manufacturerâs protocol. For each array, 10ug of amplified cRNAs were fragmented and hybridized to the array for 16 hours in a rotating hybridization oven using the Affymetrix Eukaryotic Target Hybridization Controls and protocol. Slides were stained and washed as indicated in the Antibody Amplification Stain for Eukaryotic Targets protocol using the Affymetrix Fluidics Station FS450. Arrays were then scanned with an Affymetrix Scanner 3000 and data was obtained using the Genechip® Operating Software (Version 1.2.0.037) and imported into the Rosetta Resolver system (Version 6.0).
2008-10-18 | E-GEOD-6141 | biostudies-arrayexpress
Project description:In response to stress, human cells actively downregulate ongoing gene expression programs. Translational downregulation is accompanied by the assembly of stress granules which are cytosolic condensates containing ribosomes and mRNA. Transcriptional downregulation is caused by an increased recruitment of Negative Elongation Factors (NELF) to promoters, inhibiting RNA Pol II elongation. We report here that NELF forms nuclear condensates upon stress which can be recapitulated by liquid-liquid phase separation of recombinant NELF in vitro. Stress leads to rapid dephosphorylation and SUMOylation of NELF in cells facilitating condensate formation driven by intrinsically disordered domains of NELFA and NELFE subunits. Using NELF mutants that do not form condensates we provide evidence that condensation is required for increased recruitment of NELF to downregulated promoters and cellular survival in stress. Thus, our study has uncovered a novel nuclear condensate that is conceptually similar to cytosolic stress granule in downregulating gene expression during stressful conditions.
2021-02-05 | GSE140053 | GEO
Project description:Negative elongation factor (NELF) is known to enforce promoter-proximal pausing of RNA polymerase II (Pol II), a pervasive phenomenon observed across multicellular genomes. However, the physiological impact of NELF on tissue homeostasis remains unclear. Here we show for the first time that whole-body conditional deletion of the B subunit of NELF (NELF-B) in adult mice results in cardiomyopathy and impaired response to cardiac stress. Tissue-specific knockout of NELF-B confirms its cell-autonomous function in cardiomyocytes. NELF directly supports transcription of those genes encoding rate-limiting enzymes in fatty acid oxidation and the tricarboxylic acid (TCA) cycle. NELF also shares extensively transcriptional target genes with peroxisome proliferator-activated receptors alpha (PPARalpha), a master regulator of energy metabolism in myocardium. Mechanistically, NELF helps stablize the transcription initation complex at the metabolism-related genes. Our findings strongly indicate that NELF is part of the PPARalpha-mediated transcription regulatory network that maintains metabolic homeostasis in cardiomyocytes. 3 Nelf-b f/f and 3 Nelf-b f/f; CreER female mice were injected with Tamoxifen at 8 wk old. Heart tissue were harvested at 20 wks old and used for RNA preparation.
2014-03-01 | E-GEOD-54372 | biostudies-arrayexpress
Project description:Negative elongation factor (NELF) is known to enforce promoter-proximal pausing of RNA polymerase II (Pol II), a pervasive phenomenon observed across multicellular genomes. However, the physiological impact of NELF on tissue homeostasis remains unclear. Here we show for the first time that whole-body conditional deletion of the B subunit of NELF (NELF-B) in adult mice results in cardiomyopathy and impaired response to cardiac stress. Tissue-specific knockout of NELF-B confirms its cell-autonomous function in cardiomyocytes. NELF directly supports transcription of those genes encoding rate-limiting enzymes in fatty acid oxidation and the tricarboxylic acid (TCA) cycle. NELF also shares extensively transcriptional target genes with peroxisome proliferator-activated receptors alpha (PPARalpha), a master regulator of energy metabolism in myocardium. Mechanistically, NELF helps stablize the transcription initation complex at the metabolism-related genes. Our findings strongly indicate that NELF is part of the PPARalpha-mediated transcription regulatory network that maintains metabolic homeostasis in cardiomyocytes.
2014-03-01 | GSE54372 | GEO
Project description:UV-light-induced protein-RNA cross-linking followed by MS analysis was used to identify RNA-binding regions of enhancer RNAs (eRNAs) to the negative elongation factor (NELF) complex, and NELF as part of the paused elongation complex (PEC) of human RNA polymerase II.
2022-03-08 | PXD030569 | Pride
Project description:The current work describes molecular mechanism used by the Negative elongation complex (NELF) to control the Pol II pause at genes whose transcription is induced by 20-hydroxyecdysone (20E). According to our data NELF complex is recruited to the promoters and enhancers of 20E-dependent genes. Its presence at the regulatory sites of 20E-dependent genes correlates with the described interaction of its NELF-A subunit with EcR receptor. The NELF complex, consisting of at least three subunits, is formed at the 20E-dependent promoters and participates in their active transcription and maintenance of their repressed state. NELF depletion causes a significant decrease in transcription induced by 20E. We associate this effect with the disruption of Pol II elongation complexes formation. A considerable reduction in the promoter-bound level of Spt5 subunit of DSIF was observed at the 20E-dependent genes upon NELF depletion. We presume that participation in stabilization of the Pol II-DSIF complex can be an important function of NELF with a big impact on transcription of its target genes. Part of our study was to directly link NELF to regulation of 20E-dependent genes in development. We showed presence of NELF at the promoters of 20E-dependent genes during their active transcription both in embryogenesis and metamorphosis. We also demonstrate that 20E-dependent promoters remain in a Pol II paused state at the larva stage, where they are temporarily repressed.
2021-01-10 | GSE156847 | GEO
Project description:Recent studies have found that promoter-proximal pausing occurs at most Pol2-regulated genes. DSIF and NELF function as negative elongation factors and promote Pol2 pausing. P-TEFb, whose enzymatic activity lies in the kinase Cdk9, positively regulates the transition into productive elongation by phosphorylating subunits in DSIF, NELF and Pol2. To gain insights into the interplay between these factors in regulating transcriptional pause release, we tested if knockdown of either pausing factor could bypass P-TEFb function. We find that P-TEFb function is still required for transcriptional elongation after DSIF or NELF knockdown. mES cells were infected with a shRNA hairpin to knockdown Spt5, Spt4, NelfE or control. The resulting cells were then treated with flavopiridol (1uM for 60 minutes). DNA was enriched by chromatin immunoprecipitation (ChIP) and analyzed by Solexa sequencing. A sample of whole cell extract was sequenced and used as the background to determine enrichment. ChIP was performed using an antibody against total RNA Pol2 (Rpb1 N-terminus, Santa Cruz sc-899).
2011-01-19 | E-GEOD-26658 | biostudies-arrayexpress
Project description:Epigenetic alteration is a hallmark of aging, but it remains unclear if perturbation of transcription machineries may affect longevity. NELF-mediated pausing of RNA polymerase II (RNAPII) constitutes an important step in transcription regulation. We found that halving NELF-A level in heterozygous mutants or via neuronal-specific depletion of NELF-A improves locomotor activity, stress resistance and lifespan of Drosophila significantly. Mechanistically, lower NELF-A releases paused RNAPII to facilitate productive transcription of the heat-shock protein (Hsp) genes. Elevated HSPs attenuate the level of protein aggregation, reactive oxidative species, DNA damage and systemic inflammation in the brains of NELF-A depleted flies. This protection is conserved in human cells where NELF-A depletion confers improved resistance against oxidative stress. Reduced oxidative DNA damage allows the maintenance of H3K9me2-enriched heterochromatin, which represses the activation of specific retrotransposons during aging. Therefore, by regulating transcription of Hsp genes in the brains, NELF-A controls multiple aspects of aging in Drosophila.
2020-11-30 | GSE155940 | GEO
Project description:ChIP-chip analysis of GAGA factor and NELF in Drosophila S2 cells
2008-04-04 | E-MEXP-1547 | biostudies-arrayexpress
Project description:Negative elongation factor (NELF), a four-subunit protein complex in metazoan, plays an important role in regulating promoter-proximal pausing of RNA polymerase II (RNAPII). Genetic studies demonstrate that the B subunit of mouse NELF (NELF-B) is critical for embryonic development and homeostasis in adult tissue. We report here that both human and mouse NELF-B proteins are translated from a non-AUG codon upstream of the annotated AUG. This non-AUG codon sequence is conserved in mammalian NELF-B but not NELF-B orthologs of lower metazoan. The full-length and a truncated NELF-B that starts at the first AUG codon interact with the other three NELF subunits with comparable efficiency. Furthermore, these two forms of NELF-B have a similar impact on the transcriptomics and proliferation of mouse embryonic fibroblasts. These results strongly suggest that additional amino acid sequence upstream of the annotated AUG is dispensable for the essential function of NELF in supporting cell growth in vitro. While the majority of mouse adult tissues surveyed exclusively express the full-length NELF-B protein, mouse kidney only contains a truncated NELF-B protein with the same apparent size as the AUG-initiated version. This result raises the distinct possibility that translational initiation of mouse NELF-B is regulated in a tissue-dependent manner. triplicates for ATG-Nelf-B, triplicates for FL-Nelf-B
2014-10-11 | E-GEOD-62248 | biostudies-arrayexpress