Browse
Submit Data
Databases
API
Help

Dataset Information

30 Views

0 Connections

0 Citations

0 Reanalyses

0 Downloads

Omics score: 0

Qki regulates myelinogenesis through Srebp2-dependent cholesterol biosynthesis.

ABSTRACT: Myelination depends on timely, precise control of oligodendrocyte differentiation and myelinogenesis. Cholesterol is the most abundant component of myelin and essential for myelin membrane assembly in the central nervous system. However, the underlying mechanisms of precise control of cholesterol biosynthesis in oligodendrocytes remain elusive. In the present study, we found that Qki depletion in neural stem cells or oligodendrocyte precursor cells in neonatal mice resulted in impaired cholesterol biosynthesis and defective myelinogenesis without compromising their differentiation into Aspa⁺Gstpi⁺ myelinating oligodendrocytes. Mechanistically, Qki-5 functions as a co-activator of Srebp2 to control transcription of the genes involved in cholesterol biosynthesis in oligodendrocytes. Consequently, Qki depletion led to substantially reduced concentration of cholesterol in mouse brain, impairing proper myelin assembly. Our study demonstrated that Qki-Srebp2-controlled cholesterol biosynthesis is indispensable for myelinogenesis and highlights a novel function of Qki as a transcriptional co-activator beyond its canonical function as an RNA-binding protein.

SUBMITTER: Zhou X

PROVIDER: S-EPMC8139834 | biostudies-literature |

REPOSITORIES: biostudies-literature

ACCESS DATA

Json Xml

Similar Datasets

Qki activates Srebp2-mediated cholesterol biosynthesis for maintenance of eye lens transparency.

Project description:Defective cholesterol biosynthesis in eye lens cells is often associated with cataracts; however, how genes involved in cholesterol biosynthesis are regulated in lens cells remains unclear. Here, we show that Quaking (Qki) is required for the transcriptional activation of genes involved in cholesterol biosynthesis in the eye lens. At the transcriptome level, lens-specific Qki-deficient mice present downregulation of genes associated with the cholesterol biosynthesis pathway, resulting in a significant reduction of total cholesterol level in the eye lens. Mice with Qki depletion in lens epithelium display progressive accumulation of protein aggregates, eventually leading to cataracts. Notably, these defects are attenuated by topical sterol administration. Mechanistically, we demonstrate that Qki enhances cholesterol biosynthesis by recruiting Srebp2 and Pol II in the promoter regions of cholesterol biosynthesis genes. Supporting its function as a transcription co-activator, we show that Qki directly interacts with single-stranded DNA. In conclusion, we propose that Qki-Srebp2-mediated cholesterol biosynthesis is essential for maintaining the cholesterol level that protects lens from cataract development.

| S-EPMC8139980 | biostudies-literature

Carbon dioxide regulates cholesterol levels through SREBP2.

Project description:In mammals, O2 and CO2 levels are tightly regulated and are altered under various pathological conditions. While the molecular mechanisms that participate in O2 sensing are well characterized, little is known regarding the signaling pathways that participate in CO2 signaling and adaptation. Here, we show that CO2 levels control a distinct cellular transcriptional response that differs from mere pH changes. Unexpectedly, we discovered that CO2 regulates the expression of cholesterogenic genes in a SREBP2-dependent manner and modulates cellular cholesterol accumulation. Molecular dissection of the underlying mechanism suggests that CO2 triggers SREBP2 activation through changes in endoplasmic reticulum (ER) membrane cholesterol levels. Collectively, we propose that SREBP2 participates in CO2 signaling and that cellular cholesterol levels can be modulated by CO2 through SREBP2.

| S-EPMC10651039 | biostudies-literature

Carbon dioxide regulates cholesterol levels through SREBP2

Project description:In mammals, O2 and CO2 levels are tightly regulated and are altered under various pathological conditions. While the molecular mechanisms that participate in O2 sensing are well characterized, little is known regarding the signaling pathways that participate in CO2 signaling and adaptation. Here, we show that CO2 levels control a distinct cellular transcriptional response that differs from mere pH changes. Unexpectedly, we discovered that CO2 regulates the expression of cholesterogenic genes in a SREBP2-dependent manner and modulates cellular cholesterol accumulation. Molecular dissection of the underlying mechanism suggests that CO2 triggers SREBP2 activation through changes in endoplasmic reticulum membrane cholesterol levels. Collectively, we propose that SREBP2 participates in CO2 signaling and that cellular cholesterol levels can be modulated by CO2 through SREBP2

2023-10-06 | GSE196294 | GEO

Carbon dioxide regulates cholesterol levels through SREBP2

Project description:Carbon dioxide regulates cholesterol levels through SREBP2

| PRJNA804192 | ENA

COVID-19-activated SREBP2 disturbs cholesterol biosynthesis and leads to cytokine storm.

Project description:Sterol regulatory element binding protein-2 (SREBP-2) is activated by cytokines or pathogen, such as virus or bacteria, but its association with diminished cholesterol levels in COVID-19 patients is unknown. Here, we evaluated SREBP-2 activation in peripheral blood mononuclear cells of COVID-19 patients and verified the function of SREBP-2 in COVID-19. Intriguingly, we report the first observation of SREBP-2 C-terminal fragment in COVID-19 patients' blood and propose SREBP-2 C-terminal fragment as an indicator for determining severity. We confirmed that SREBP-2-induced cholesterol biosynthesis was suppressed by Sestrin-1 and PCSK9 expression, while the SREBP-2-induced inflammatory responses was upregulated in COVID-19 ICU patients. Using an infectious disease mouse model, inhibitors of SREBP-2 and NF-κB suppressed cytokine storms caused by viral infection and prevented pulmonary damages. These results collectively suggest that SREBP-2 can serve as an indicator for severity diagnosis and therapeutic target for preventing cytokine storm and lung damage in severe COVID-19 patients.

| S-EPMC7471497 | biostudies-literature

PIN1 isomerase promotes the initiation and progression of bladder cancer through SREBP2-mediated cholesterol biosynthesis pathway

Project description:Bladder cancer, one of the most diagnosed cancers worldwide, is associated with high morbidity, mortality, and a poor prognosis. The PIN1 phospho-dependent prolyl isomerase is frequently overexpressed in many human cancer types and affects tumor initiation and progression through disrupting the balance of oncoprotein and tumor suppressor protein signaling. However, the functional pSer/Thr.Pro protein substrates of PIN1 and its effects on downstream signaling in bladder carcinogenesis remain largely unknown. Phenotypically, we discovered that ablation of Pin1 in human/mouse bladder cancer cells and organoids formed from mouse primary urothelial cells resulted in decreased cell proliferation, stemness maintenance, cell invasion, migration, urothelium clearance capacity, and reduced free/total cholesterol levels in vitro. Re-expressing Pin1 in Pin1 knockout cells reversed the defects caused by lack of Pin1. Moreover, in vivo subcutaneous xenograft and allograft transplantation mouse models combined with an orthotopic implantation model were utilized to confirm a positive role for Pin1 in controlling tumor growth and potential metastasis. Therapeutically, a combination of the sulfopin PIN1 inhibitor and the simvastatin HMGCR inhibitor was shown to suppress cell proliferation in vitro and tumor growth in vivo synergistically. Mechanistically, we observed a negative enrichment of SREBP2-driven cholesterol metabolism pathways in PIN1 knockout cells via RNA-sequencing and used a suite of diverse molecular and biochemical approaches to show that PIN1 interacts with JNK-dependent phosphorylated SREBP2 (Ser455) and vice versa. These results indicate that active cholesterol biosynthesis pathway in bladder cancer cells is regulated by PIN1-mediated isomerization and JNK-mediated phosphorylation of its key transcriptional factor SREBP2. These findings emphasize that PIN1 can act as a regulator and potential therapeutic target in bladder cancer.

2024-11-17 | GSE262761 | GEO

Inhibition of cholesterol biosynthesis through RNF145-dependent ubiquitination of SCAP.

Project description:Cholesterol homeostasis is maintained through concerted action of the SREBPs and LXRs. Here, we report that RNF145, a previously uncharacterized ER membrane ubiquitin ligase, participates in crosstalk between these critical signaling pathways. RNF145 expression is induced in response to LXR activation and high-cholesterol diet feeding. Transduction of RNF145 into mouse liver inhibits the expression of genes involved in cholesterol biosynthesis and reduces plasma cholesterol levels. Conversely, acute suppression of RNF145 via shRNA-mediated knockdown, or chronic inactivation of RNF145 by genetic deletion, potentiates the expression of cholesterol biosynthetic genes and increases cholesterol levels both in liver and plasma. Mechanistic studies show that RNF145 triggers ubiquitination of SCAP on lysine residues within a cytoplasmic loop essential for COPII binding, potentially inhibiting its transport to Golgi and subsequent processing of SREBP-2. These findings define an additional mechanism linking hepatic sterol levels to the reciprocal actions of the SREBP-2 and LXR pathways.

| S-EPMC5656429 | biostudies-literature

Rspo1/Rspo3-LGR4 signaling inhibits hepatic cholesterol synthesis through the AMPKα-SREBP2 pathway.

Project description:R-spondins (Rspos) are endogenous ligands of leucine-rich repeat-containing G-protein-coupled receptor 4 (LGR4). Rspos-LGR4 signaling plays important roles in embryogenesis, gastrointestinal homeostasis, and food intake. Here, we investigated the impacts of Rspos-LGR4 on hepatic cholesterol synthesis. Rspo1/3 and Lgr4 knockdown mice were used to investigate the impacts of Rspo1/3-LGR4 on hepatic cholesterol synthesis. AMPKα agonist, antagonist, and shRNA were used to explore the downstream targets of Rspos-LGR4 signaling. In our study, we reported that LGR4, Rspo1, and Rspo3 were highly expressed in hepatocytes and their expressions were sensitive to energy states. Rspo1 and Rspo3 reversed OA-induced cholesterol synthesis, accompanying with increased the phosphorylation of AMPKα Thr172, reduced SREBP2 nuclear translocation, and Srebf2 mRNA expression. Conversely, hepatic LGR4 knockdown increased hepatic cholesterol synthesis and decreased the phosphorylation of AMPKα both in vitro and in vivo. Activation or inhibition of AMPKα significantly abolished the effects of LGR4 deficiency or Rspos, respectively, on cholesterol synthesis. Knockdown of AMPKα1 or/and AMPKα2 repressed Rspos-induced inhibition on cholesterol synthesis. Our study indicates that Rspo1/Rspo3-LGR4 signaling in hepatocytes suppresses cholesterol synthesis via the AMPKα-SREBP2 pathway.

| S-EPMC8016451 | biostudies-literature

Podocalyxin-Like Protein 1 Regulates Pluripotency through the Cholesterol Biosynthesis Pathway

Project description:Deciphering signaling mechanisms critical for the extended pluripotent stem cell (EPSC) state and primed pluripotency is necessary for understanding embryonic development. Here, we identify a membrane protein, Podocalyxin-like protein 1 (PODXL) as being essential for extended and primed pluripotency. Alteration of PODXL expression levels affects self-renewal, protein expression of c-MYC and telomerase, and induced pluripotent stems cell (iPSC) and EPSC colony formation. PODXL is the first membrane protein reported to regulate de novo cholesterol biosynthesis, and human pluripotent stem cells (hPSCs) are more sensitive to cholesterol depletion than fibroblasts. The addition of exogenous cholesterol fully restores PODXL knockdown-mediated loss of pluripotency. PODXL affects lipid raft dynamics via the regulation of cholesterol. PODXL recruits the RAC1/CDC42/actin network to regulate SREBP1 and SREBP2 maturation and lipid raft dynamics. Single-cell RNA sequencing reveals PODXL overexpression enhanced chimerism between human cells in mouse host embryos (hEPSCs 57%). Interestingly, in the human-mouse chimeras, laminin and collagen signaling-related pathways are dominant in PODXL overexpressing cells. We conclude that cholesterol regulation via PODXL signaling is critical for ESC/EPSC.

2022-09-22 | GSE213618 | GEO

NRF3 upregulates gene expression in SREBP2-dependent mevalonate pathway with cholesterol uptake and lipogenesis inhibition.

Project description:Lipids, such as cholesterol and fatty acids, influence cell signaling, energy storage, and membrane formation. Cholesterol is biosynthesized through the mevalonate pathway, and aberrant metabolism causes metabolic diseases. The genetic association of a transcription factor NRF3 with obesity has been suggested, although the molecular mechanisms remain unknown. Here, we show that NRF3 upregulates gene expression in SREBP2-dependent mevalonate pathway. We further reveal that NRF3 overexpression not only reduces lanosterol, a cholesterol precursor, but also induces the expression of the GGPS1 gene encoding an enzyme in the production of GGPP from farnesyl pyrophosphate (FPP), a lanosterol precursor. NRF3 overexpression also enhances cholesterol uptake through RAB5-mediated macropinocytosis process, a bulk and fluid-phase endocytosis pathway. Moreover, we find that GGPP treatment abolishes NRF3 knockdown-mediated increase of neutral lipids. These results reveal the potential roles of NRF3 in the SREBP2-dependent mevalonate pathway for cholesterol uptake through macropinocytosis induction and for lipogenesis inhibition through GGPP production.

| S-EPMC8506969 | biostudies-literature

OmicsDI is part of the ELIXIR infrastructure

OmicsDI is an Elixir interoperability service. Learn more ›

Tweets

OmicsDI Databases

PRIDE
PeptideAtlas
MassIVE
JPOST Repository
Physiome Model Repository

EGA
EVA
ENA
LINCS
PAXDB
Cell Collective

MetaboLights
Metabolomics Workbench
MetabolomeExpress
GNPS
BioModels
FAIRDOMHub

ArrayExpress
dbGaP
ExpressionAtlas
GEO
NODE

Information

Databases
Help
API
Contact us
Code on GitHub
Terms of use
Submit Data