Browse
Submit Data
Databases
API
Help

Dataset Information

0 Views

0 Connections

0 Citations

0 Reanalyses

0 Downloads

Omics score: 0

The DEAD-box helicase Hlc regulates basal transcription and chromatin opening of stress-responsive genes

ABSTRACT: Stress-responsive genes are lowly transcribed under normal conditions and robustly induced in response to stress. The significant difference between basal and induced transcription indicates that the general transcriptional machinery requires a mechanism to distinguish each transcription state. However, what factors specifically function in basal transcription remains poorly understood. Using a classic model stress-responsive gene (Drosophila MtnA), we found that knockdown of the DEAD-box helicase Hlc resulted in a significant transcription attenuation of MtnA under normal, but not stressed, conditions. Mechanistically, Hlc directly binds to the MtnA locus to maintain the accessibility of chromatin near the transcriptional start site, which allows the recruitment of RNA polymerase II and subsequent MtnA transcription. Using RNA-seq, we then identified plenty of additional stress-responsive genes whose basal transcription was reduced upon knockdown of Hlc. Taken together, these data suggest that Hlc-mediated transcription regulation is an essential and widespread mechanism for precise control of stress-responsive genes.

ORGANISM(S): Drosophila melanogaster

PROVIDER: GSE205804 | GEO | 2022/07/24

REPOSITORIES: GEO

ACCESS DATA

Json Xml

Dataset's files

Source:

			Action	DRS
		Other

Items per page:

1 - 1 of 1

Similar Datasets

Drosophila melanogaster

Project description:The DEAD-box helicase Hlc regulates basal transcription and chromatin opening of stress-responsive genes

| PRJNA844545 | ENA

Maximizing HLC production in bioreactors: unveiling the role of oxygen control for enhanced yield and PH1 disease modelling

Project description:Hepatocytes-like cells (HLC) derived from human induced pluripotent stem cells show great promise for cell-based liver therapies and disease modelling. However, their application is currently hindered by the low production yields of existing protocols. We aim to develop a bioprocess able to generate high numbers of HLC. We used stirred-tank bioreactors with a rational control of dissolved oxygen concentration (DO) for the optimization of HLC production as 3D aggregates. We evaluated the impact of controlling DO at physiological levels (4%O2) during hepatic progenitors’ stage on cell proliferation and differentiation efficiency. Whole transcriptome analysis and biochemical assays were performed to provide a detailed characterization of HLC quality attributes. When DO was controlled at 4%O2 during the hepatic progenitors’ stage, cells presented an upregulation of genes associated with hypoxia-inducible factor pathway and a downregulation of oxidative stress genes. This condition promoted higher HLC production (maximum cell concentration: 2×106 cell/mL) and improved differentiation efficiencies (80% Albumin-positive cells) when compared to the bioreactor operated under atmospheric oxygen levels (21%O2, 0.6×106 cell/mL, 43% Albumin positive cells). These HLC exhibited functional characteristics of hepatocytes: capacity to metabolize drugs, ability to synthesize hepatic metabolites, and inducible cytochrome P450 activity. Bioprocess robustness was confirmed with HLC derived from different donors, including a primary hyperoxaluria type 1 (PH1) patient. The generated PH1.HLC showed metabolic features of PH1 disease with higher secretion of oxalate compared with HLC generated from healthy individuals. This work reports a reproducible bioprocess, that shows the importance of controlling DO at physiological levels to increase HLC production, and the HLC capability to display PH1 disease features.

2024-10-23 | GSE267210 | GEO

Stress-induced translation of KCNB1 contributes to the enhanced synaptic transmission of the lateral habenula

Project description:The lateral habenula (LHb) is a well-established brain region involved in depressive disorders. Synaptic transmission of the LHb neurons is known to be enhanced by stress exposure; however, little is known about genetic modulators within the LHb that respond to stress. Using recently developed molecular profiling methods by phosphorylated ribosome capture, we obtained transcriptome profiles of stress responsive LHb neurons during acute physical stress. Among such genes, we found that KCNB1 (Kv2.1 channel), a delayed rectifier and voltage-gated potassium channel, exhibited increased expression following acute stress exposure. To determine the roles of KCNB1 on LHb neurons during stress, we injected short hairpin RNA (shRNA) against the kcnb1 gene to block its expression prior to stress exposure. We observed that the knockdown of KCNB1 altered the basal firing pattern of LHb neurons. Although KCNB1 blockade did not rescue despair-like behaviors in acute learned helplessness (aLH) animals, we found that KCNB1 knockdown prevented the enhancement of synaptic strength in LHb neuron after stress exposure. This study suggests that KCNB1 may contribute to shape stress responses by regulating basal firing patterns and neurotransmission intensity of LHb neurons.

2023-12-05 | GSE249051 | GEO

Differential Role of NKG2D in Recognition and Killing of Hepatic Lineage Cells Derived from Embryonic Stem Cells and Induced Pluripotent Stem Cells

Project description:Recent advances towards the efficient and reproducible differentiation of stem cells into hepatocyte-like cells (HLC) have created potential opportunities in clinical transplantation. For this approach to be successfully translated, however, it is necessary to understand the immune response to stem cell-derived cellular products. Whereas both embryonic stem cells and induced pluripotent stem cells have been utilized as cellular sources for differentiation and lineage specification, their relative ability to be recognized by immune effector cells is unclear. Here we determine the expression of immune recognition molecules on HLC generated from murine embryonic stem cells and induced pluripotent stem cells, compared to adult hepatocytes, and we evaluate the impact on recognition by NK cells. We report that HLC lack MHC class I expression, and that embryonic stem cell derived-HLC have higher expression of the NK cell activating ligands Rae1, H60, and Mult1 than induced pluripotent stem cell-derived HLC and adult hepatocytes. Moreover, the lack of MHC class I render embryonic stem cell derived-HLC, and induced pluripotent stem cell derived-HLC, susceptible to killing by syngeneic and allogeneic NK cells. Both embryonic stem cell derived-HLC, and induced pluripotent stem cell derived-HLC, are killed by NK cells at higher levels than adult hepatocytes. Finally, we demonstrate that the NK cell activation receptor, NKG2D, plays a key role in NK cell killing of embryonic stem cell derived-HLC, but not induced pluripotent stem cell-derived HLC. Hepatocytes were isolated from FVB/NJ mice and C57Bl/6 mice using a modification of the Seglen’s perfusion technique.

2017-11-14 | GSE106829 | GEO

Gene expression profile of human embryonic stem cell-derived hepatocyte-like cells

Project description:The differentiation of pluripotent stem cells to hepatocyte-like cells offers the perspective of unlimited supply of human hepatocytes. However, the degree of differentiation of hepatic-like cells (HLC) remains controversial. To obtain an unbiased characterization, we performed a transcriptomics study using the Affymetrix Gene ChipÂ® HG-U133 plus 2.0, with HLC derived from embryonic and induced stem cells (ESC, hiPSC) from two different laboratories. Genome-wide gene expression profiles of ESC and HLC were compared to freshly isolated and up to 14 days cultivated primary human hepatocytes (see submission E-MTAB-3994) obtained under patient informed consent from three male donors. Three biological replicas were used for each ESC and HLC models. (associated data set: E-MTAB-3994 - Gene expression profile of human embryonic stem cell-derived hepatocyte-like cells in matrigel and recombinant laminins)

2016-02-24 | E-MTAB-4442 | biostudies-arrayexpress

Improved maturity and yield of pluripotent stem cell-derived hepatocytes for 2D and 3D modeling of human liver pathophysiology

Project description:Robust and scalable differentiation of human pluripotent stem cells into high-quality hepatocyte-like cells (HLC) is achieved by acting on Wnt/b-catenin and TGFb pathways and taking advantage of latest knowledge on human liver development. Obtained HLC are comparable to primary human hepatocytes and superior to stem cell-derived hepatocytes generated with previously described protocols. As a proof of concept, such HLC were used to assess drug hepatotoxicity and study human ductal plate and bile duct morphogenesis in a complex liver organoid model.

2022-02-03 | GSE152390 | GEO

The DEAD-box helicase Hlc regulates basal transcription and chromatin opening of stress-responsive genes.

Project description:Stress-responsive genes are lowly transcribed under normal conditions and robustly induced in response to stress. The significant difference between basal and induced transcription indicates that the general transcriptional machinery requires a mechanism to distinguish each transcription state. However, what factors specifically function in basal transcription remains poorly understood. Using a classic model stress-responsive gene (Drosophila MtnA), we found that knockdown of the DEAD-box helicase Hlc resulted in a significant transcription attenuation of MtnA under normal, but not stressed, conditions. Mechanistically, Hlc directly binds to the MtnA locus to maintain the accessibility of chromatin near the transcriptional start site, which allows the recruitment of RNA polymerase II and subsequent MtnA transcription. Using RNA-seq, we then identified plenty of additional stress-responsive genes whose basal transcription was reduced upon knockdown of Hlc. Taken together, these data suggest that Hlc-mediated basal transcription regulation is an essential and widespread mechanism for precise control of stress-responsive genes.

| S-EPMC9458421 | biostudies-literature

Transcription profiling of human MCF7 cells following short-term E deprivation, ER-alpha siRNA knockdown and oxidant treatments

Project description:To investigate the oxidant sensitivity of E/ER regulated gene expression, E/ER regulated genes are identified using E deprivation or; ER-alpha siRNA knockdown; and oxidative stress responsive is determined by 8hr exposure to diamide, hydrogen peroxide and menadione Experiment Overall Design: MCF7 cells were treated under various conditions to identifiy oxidative stress responsive E/ER regulated genes. Association of these genes with respect to tumor phenotypes are assessed

2008-11-13 | E-GEOD-10061 | biostudies-arrayexpress

DHH1/DDX6-like RNA helicases maintain ephemeral half-lives of stress-response mRNAs

Project description:Gene transcription is counterbalanced by mRNA decay processes that regulate transcript quality and quantity. We show here that the evolutionarily conserved DHH1/DDX6-like RNA HELICASEs of Arabidopsis thaliana control the ephemerality of a subset of cellular mRNAs. These RNA helicases co-localize with key markers of processing bodies and stress granules and contribute to their subcellular dynamics. They function to limit the precocious accumulation and translation of stress-responsive mRNAs associated with autoimmunity and growth inhibition under non-stress conditions. Given the conservation of this RH subfamily, they may control basal levels of conditionally-regulated mRNAs in diverse eukaryotes, accelerating responses without penalty.

2020-04-29 | GSE136713 | GEO

Marchantia polymorpha

Project description:Salinity stress-responsive transcription factors in the liverwort Marchantia polymorpha

| PRJDB6783 | ENA