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Journal of Inflammation Research 2022Nuclear paraspeckle assembly transcript 1 (Neat1) located at chromosome 11 is a long non-coding RNA that is widely expressed in mammalian cell types, and which is... (Review)
Review
Nuclear paraspeckle assembly transcript 1 (Neat1) located at chromosome 11 is a long non-coding RNA that is widely expressed in mammalian cell types, and which is overexpressed in several inflammation-related disorders. Inflammation implies a plethora of mutual interactions between both soluble factors and cells due to various stimuli including tissue injury. Although there is no doubt that inflammation is critically involved in multiple biological and pathological processes alike, the precise mechanisms being involved are still open for debate. In this context, the role of Neat1 as a regulator of inflammation, microglial activation, and lipid accumulation under various inflammatory conditions remains elusive. Herein, we review the regulation of Neat1 and how it modulates the expression of its target genes. Thereafter, we will review the impact of Neat1 on inflammation by activating or inhibiting various signaling pathways, such as microRNAs, AKT, TLR4, TRAF6, and NF-κB.
PubMed: 35115805
DOI: 10.2147/JIR.S338162 -
Bioengineered Feb 2022Long non-coding RNA nuclear paraspeckle assembly transcript 1 (NEAT1) is a novel pro-inflammatory factor in severe human diseases. Since inflammatory plays important...
Long non-coding RNA nuclear paraspeckle assembly transcript 1 (NEAT1) is a novel pro-inflammatory factor in severe human diseases. Since inflammatory plays important roles in periodontitis progression, we aimed to explore the role of NEAT1 in chronic periodontitis (CP) in vitro. We established a periodontitis cell model was established by lipopolysaccharide (Pg-LPS)-induced periodontal ligament cells (PDLCs). Quantitative reverse transcription polymerase chain reaction (qRT-PCR) was performed to detect the expression of NEAT1, microRNA (miR)-200c-3p, and tumor necrosis factor receptor-associated factor 6 (). Cell viability, inflammatory factors, and protein expression of Bcl-2, Bax, and were analyzed by MTT, enzyme-linked immunosorbent assay, and Western blot. The target relationships among NEAT1, miR-200c-3p, and were predicted by the StarBase/TargetScan software, and further validated by dual-luciferase reporter assay. In this research, NEAT1 is up-regulated in CP tissues and periodontitis model group. Silencing of NEAT1 and over-expression of miR-200c-3p enhanced cell viability and repressed apoptosis in the periodontitis model group. NEAT1 targets miR-200c-3p, and miR-200c-3p further targets . MiR-200c-3p inhibitor or over-expression of reversed the promoting effect of NEAT1 knockdown on cell viability, and the inhibiting effects on inflammatory cytokines and cell apoptosis. Consequently, the silencing of NEAT1 inhibits inflammation and apoptosis via targeting miR-200c-3p/ axis, thereby contributing to alleviate the progression of CP. This finding could provide an underlying target for the treatment of CP.
Topics: Bacteroidaceae Infections; Chronic Periodontitis; Female; Humans; Male; Models, Biological; Periodontal Ligament; Porphyromonas gingivalis; RNA, Long Noncoding
PubMed: 35034548
DOI: 10.1080/21655979.2021.2018387 -
Nucleic Acids Research Jan 2022The Drosophila behaviour/human splicing (DBHS) proteins are a family of RNA/DNA binding cofactors liable for a range of cellular processes. DBHS proteins include the...
The Drosophila behaviour/human splicing (DBHS) proteins are a family of RNA/DNA binding cofactors liable for a range of cellular processes. DBHS proteins include the non-POU domain-containing octamer-binding protein (NONO) and paraspeckle protein component 1 (PSPC1), proteins capable of forming combinatorial dimers. Here, we describe the crystal structures of the human NONO and PSPC1 homodimers, representing uncharacterized DBHS dimerization states. The structures reveal a set of conserved contacts and structural plasticity within the dimerization interface that provide a rationale for dimer selectivity between DBHS paralogues. In addition, solution X-ray scattering and accompanying biochemical experiments describe a mechanism of cooperative RNA recognition by the NONO homodimer. Nucleic acid binding is reliant on RRM1, and appears to be affected by the orientation of RRM1, influenced by a newly identified 'β-clasp' structure. Our structures shed light on the molecular determinants for DBHS homo- and heterodimerization and provide a basis for understanding how DBHS proteins cooperatively recognize a broad spectrum of RNA targets.
Topics: DNA-Binding Proteins; Dimerization; Humans; Models, Molecular; Protein Conformation; RNA; RNA Splicing; RNA-Binding Proteins
PubMed: 34904671
DOI: 10.1093/nar/gkab1216 -
Circulation Journal : Official Journal... May 2022Nuclear paraspeckle assembly transcript 1 (NEAT1) has been reported to be involved in the progression of many cancers; however, the role and mechanisms underlying NEAT1...
Nuclear Paraspeckle Assembly Transcript 1 Enhances Hydrogen Peroxide-Induced Human Vascular Smooth Muscle Cell Injury by Regulating miR-30d-5p/A Disintegrin and Metalloprotease 10.
BACKGROUND
Nuclear paraspeckle assembly transcript 1 (NEAT1) has been reported to be involved in the progression of many cancers; however, the role and mechanisms underlying NEAT1 in abdominal aortic aneurysm (AAA) remain unclear.Methods and Results: The expression of NEAT1, miR-30d-5p and A disintegrin and metalloprotease 10 (ADAM10) was measured by qRT-PCR and western blot. Functional experiments were conducted by using a CCK-8 assay, EDU assay, flow cytometry, western blot, ELISA, and commercial kits. The target relation was confirmed by dual-luciferase reporter assay and the RIP assay. It was then found that NEAT1 was upregulated in peripheral blood of AAA patients ~3.46-fold, smooth muscle cells (SMCs) isolated from AAA tissues ~2.6-fold and in a hydrogen peroxide (HO)-induced injury model of human vascular SMC (HVSMCs) ~2.0- and 3.9-fold at 50 µmol/L and 200 µmol/L HOtreatment, respectively. NEAT1 deletion attenuated HO-induced cell proliferation promotion (40.0% vs. 74.3%), apoptosis inhibition (25.0% vs. 13.5%), and reduction of inflammatory response and oxidative stress in HVSMCs. Mechanistically, NEAT1 targeted miR-30d-5p to prevent the degradation of its target, ADAM10, in HVSMCs. Further rescue experiments suggested miR-30d-5p inhibition mitigated the effects of NEAT1 deletion on HO-induced HVSMCs. Moreover, ADAM10 overexpression counteracted the inhibitory functions of miR-30d-5p on HO-evoked HVSMC injury.
CONCLUSIONS
NEAT1 promoted HO-induced HVSMC injury by inducing cell apoptosis, inflammation and oxidative stress through miR-30d-5p/ADAM10 axis, indicating the possible involvement of NEAT1 in the pathogenesis of AAA.
Topics: Apoptosis; Carrier Proteins; Cell Proliferation; Disintegrins; Humans; Hydrogen Peroxide; Metalloproteases; MicroRNAs; Muscle, Smooth, Vascular; Myocytes, Smooth Muscle; Paraspeckles; RNA, Long Noncoding
PubMed: 34880199
DOI: 10.1253/circj.CJ-21-0042 -
Cell Metabolism Dec 2021Accelerated glycolysis is the main metabolic change observed in cancer, but the underlying molecular mechanisms and their role in cancer progression remain poorly...
Accelerated glycolysis is the main metabolic change observed in cancer, but the underlying molecular mechanisms and their role in cancer progression remain poorly understood. Here, we show that the deletion of the long noncoding RNA (lncRNA) Neat1 in MMTV-PyVT mice profoundly impairs tumor initiation, growth, and metastasis, specifically switching off the penultimate step of glycolysis. Mechanistically, NEAT1 directly binds and forms a scaffold bridge for the assembly of PGK1/PGAM1/ENO1 complexes and thereby promotes substrate channeling for high and efficient glycolysis. Notably, NEAT1 is upregulated in cancer patients and correlates with high levels of these complexes, and genetic and pharmacological blockade of penultimate glycolysis ablates NEAT1-dependent tumorigenesis. Finally, we demonstrate that Pinin mediates glucose-stimulated nuclear export of NEAT1, through which it exerts isoform-specific and paraspeckle-independent functions. These findings establish a direct role for NEAT1 in regulating tumor metabolism, provide new insights into the Warburg effect, and identify potential targets for therapy.
Topics: Animals; Breast Neoplasms; Cell Line, Tumor; Cell Proliferation; Female; Gene Expression Regulation, Neoplastic; Glycolysis; Humans; Mice; MicroRNAs; RNA, Long Noncoding
PubMed: 34879239
DOI: 10.1016/j.cmet.2021.11.011 -
Aging Nov 2021Long noncoding RNA nuclear paraspeckle assembly transcript 1 (lncRNA NEAT1) is abnormally expressed in numerous tumors and functions as an oncogene, but the role of...
Long noncoding RNA nuclear paraspeckle assembly transcript 1 (lncRNA NEAT1) is abnormally expressed in numerous tumors and functions as an oncogene, but the role of NEAT1 in laryngocarcinoma is largely unknown. Our study validated that NEAT1 expression was markedly upregulated in laryngocarcinoma tissues and cells. Downregulation of NEAT1 dramatically suppressed cell proliferation and invasion through inhibiting miR-524-5p expression. Additionally, NEAT1 overexpression promoted cell growth and metastasis, while overexpression of miR-524-5p could reverse the effect. NEAT1 increased the expression of histone deacetylase 1 gene (HDAC1) via sponging miR-524-5p. Mechanistically, overexpression of HDAC1 recovered the cancer-inhibiting effects of miR-524-5p mimic or NEAT1 silence by deacetylation of tensin homolog deleted on chromosome ten (PTEN) and inhibiting AKT signal pathway. Moreover, experiments indicated that silence of NEAT1 signally suppressed tumor growth. Taken together, knockdown of NEAT1 suppressed laryngocarcinoma cell growth and metastasis by miR-524-5p/HDAC1/PTEN/AKT signal pathway, which provided a potential therapeutic target for laryngocarcinoma.
Topics: Acetylation; Adult; Cell Proliferation; Female; Histone Deacetylase 1; Humans; Laryngeal Neoplasms; Male; MicroRNAs; Middle Aged; Neoplasm Invasiveness; PTEN Phosphohydrolase; RNA, Long Noncoding
PubMed: 34837887
DOI: 10.18632/aging.203719 -
Molecular Therapy Oncolytics Dec 2021hnRNPK is a multifunctional protein that plays an important role in cancer cell proliferation and metastasis via its RNA- and DNA-binding properties. Previously we...
hnRNPK is a multifunctional protein that plays an important role in cancer cell proliferation and metastasis via its RNA- and DNA-binding properties. Previously we showed that cell-penetrating peptides derived from the RGG RNA-binding domain of SAFA (hnRNPU) disrupt cancer cell proliferation and survival. Here we explore the efficacy of a peptide derived from the RGG domain of hnRNPK. This peptide acts in a dominant-negative manner on several hnRNPK functions to induce death of multiple types of cancer cells. The peptide phenocopies the effect of hnRNPK knockdown on its mRNA-stability targets such as and and alters the levels and locations of long non-coding RNAs (lncRNAs) and proteins required for nuclear and paraspeckle formation and function. The RGG-derived peptide also decreases euchromatin as evidenced by loss of active marks and polymerase II occupancy. Our findings reveal the potential therapeutic utility of the hnRNPK RGG-derived peptide in a range of cancers.
PubMed: 34820504
DOI: 10.1016/j.omto.2021.10.004 -
International Journal of Ophthalmology 2021To explore the regulatory mechanism of nuclear paraspeckle assembly transcript 1 (NEAT1) in the pathogenesis of posterior capsule opacification (PCO).
AIM
To explore the regulatory mechanism of nuclear paraspeckle assembly transcript 1 (NEAT1) in the pathogenesis of posterior capsule opacification (PCO).
METHODS
Quantitative reverse transcription polymerase chain reaction (RT-qPCR) was executed to analyze NEAT1 and microRNA (miR)-26a-5p expression in transforming growth factor-beta 2 (TGF-β2)-disposed lens epithelial cells (LECs). The proliferation, cell cycle progression, apoptosis, and migration of TGF-β2-disposed LECs were evaluated. The relationship between NEAT1 or fanconi anemia (FA) complementation group E (FANCE) and miR-26a-5p was verified by dual-luciferase reporter assay.
RESULTS
TGF-β2 induced NEAT1 expression in LECs. NEAT1 inhibition accelerated apoptosis, cell cycle arrest, decreased proliferation, epithelial-mesenchymal transition (EMT), and migration of TGF-β2-disposed LECs. NEAT1 sponged miR-26a-5p to further regulate FANCE expression. Rescue experiments presented that miR-26a-5p downregulation overturned NEAT1 silencing-mediated impacts on TGF-β2-disposed LEC biological behaviors. Additionally, FANCE overexpression reversed miR-26a-5p mimic-mediated impacts on TGF-β2-disposed LEC biological behaviors.
CONCLUSION
TGF-β2-induced NEAT1 facilitates LEC proliferation, migration, and EMT by upregulating FANCE sequestering miR-26a-5p.
PubMed: 34804856
DOI: 10.18240/ijo.2021.11.05 -
International Journal of Molecular... Nov 2021Extracellular matrix (ECM)-derived mechanical stimuli regulate many cellular processes and phenotypes through mechanotransduction signaling pathways. Substrate stiffness...
BACKGROUND
Extracellular matrix (ECM)-derived mechanical stimuli regulate many cellular processes and phenotypes through mechanotransduction signaling pathways. Substrate stiffness changes cell phenotypes and promotes angiogenesis, epithelial to mesenchymal transition (EMT), and metastasis in tumors. Enhanced liver tissue matrix stiffness plays a crucial role in the tumorigenesis and malignant development of liver cancer and is associated with unfavorable survival outcomes. However, how liver cancer cells sense changes in ECM stiffness and the underlying molecular mechanisms are largely unknown.
METHODS
Seeding HepG2 cells on the micropillar gels, HepG2 cells were assessed for responsiveness to mechanotransduction using Western blot and immunofluorescence.
CONCLUSIONS
We found that higher substrate stiffness dramatically enhanced malignant cell phenotypes and promoted G1/S transition in HepG2 cells. Furthermore, nuclear paraspeckle assembly transcript 1 () was identified as a matrix stiffness-responsive long non-coding RNA (lncRNA) regulating proliferation and EMT in response to increasing matrix stiffness during the progression of HepG2 cells towards liver cancer phenotypes. Higher matrix stiffness contributed to enhancing expression, which activated the WNT/β-catenin pathway. β-catenin translocates and enters the nucleus and the EMT transcription factor zinc finger E-box binding homeobox 1 (ZEB1) was upregulated to trigger EMT. Additionally, the proteins required for matrix stiffness-induced proliferation and resistance were strikingly upregulated in HepG2 cells. Therefore, our findings provide evidence that ECM-derived mechanical signals regulate cell proliferation and drive EMT through a /WNT/β-catenin mechanotransduction pathway in the tumor microenvironment of liver cancer.
Topics: Animals; Cell Line, Tumor; Cell Movement; Cell Proliferation; Epithelial-Mesenchymal Transition; Extracellular Matrix; Female; Humans; Liver Neoplasms; Mechanotransduction, Cellular; Mice; Mice, Nude; RNA, Long Noncoding; Wnt Signaling Pathway; Zinc Finger E-box-Binding Homeobox 1; beta Catenin
PubMed: 34769497
DOI: 10.3390/ijms222112066 -
Hybridization-proximity labeling reveals spatially ordered interactions of nuclear RNA compartments.Molecular Cell Jan 2022The ability of RNAs to form specific contacts with other macromolecules provides an important mechanism for subcellular compartmentalization. Here we describe a suite of...
The ability of RNAs to form specific contacts with other macromolecules provides an important mechanism for subcellular compartmentalization. Here we describe a suite of hybridization-proximity (HyPro) labeling technologies for unbiased discovery of proteins (HyPro-MS) and transcripts (HyPro-seq) associated with RNAs of interest in genetically unperturbed cells. As a proof of principle, we show that HyPro-MS and HyPro-seq can identify both known and previously unexplored spatial neighbors of the noncoding RNAs 45S, NEAT1, and PNCTR expressed at markedly different levels. Notably, HyPro-seq uncovers an extensive repertoire of incompletely processed, adenosine-to-inosine-edited transcripts accumulating at the interface between their encoding chromosomal regions and the NEAT1-containing paraspeckle compartment. At least some of these targets require NEAT1 for their optimal expression. Overall, this study provides a versatile toolkit for dissecting RNA interactomes in diverse biomedical contexts and expands our understanding of the functional architecture of the mammalian nucleus.
Topics: Cell Compartmentation; Cell Nucleus; Genetic Techniques; HeLa Cells; Humans; Mass Spectrometry; Proof of Concept Study; Protein Binding; Proteome; RNA, Long Noncoding; RNA, Nuclear; RNA, Ribosomal; RNA-Binding Proteins; RNA-Seq; Transcriptome
PubMed: 34741808
DOI: 10.1016/j.molcel.2021.10.009