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Discover Oncology Nov 2022The NONO protein belongs to the multifunctional family of proteins that can bind DNA, RNA and proteins. It is located in the nucleus of most mammalian cells and can...
Expression levels of NONO, a nuclear protein primarily involved in paraspeckles function, are associated with several deregulated molecular pathways and poor clinical outcome in multiple myeloma.
PURPOSE
The NONO protein belongs to the multifunctional family of proteins that can bind DNA, RNA and proteins. It is located in the nucleus of most mammalian cells and can affect almost every step of gene regulation. Dysregulation of NONO has been found in many types of cancer; however, data regarding its expression and relevance in Multiple Myeloma (MM) are virtually absent.
METHODS
We took advantage of a large cohort of MM patients enrolled in the Multiple Myeloma Research Foundation CoMMpass study to elucidate better the clinical and biological relevance of NONO expression in the context of the MM genomic landscape and transcriptome.
RESULTS
NONO is overexpressed in pathological samples compared to normal controls. In addition, higher NONO expression levels are significant independent prognostic markers of worse clinical outcome in MM. Our results indicate that NONO deregulation may play a pathogenetic role in MM by affecting cell cycle, DNA repair mechanisms, and influencing translation by regulating ribosome biogenesis and assembly. Furthermore, our data suggest NONO involvement in the metabolic reprogramming of glucose metabolism from respiration to aerobic glycolysis, a phenomenon known as the 'Warburg Effect' that supports rapid cancer cell growth, survival, and invasion.
CONCLUSION
These findings strongly support the need of future investigations for the understanding of the mechanisms of deregulation and the biological role and activity of NONO in MM.
PubMed: 36367609
DOI: 10.1007/s12672-022-00582-2 -
International Journal of Molecular... Oct 2022More research is required to understand how melatonin protects neurons. The study aimed to find out if and how long non-coding RNA (lncRNA) contributes to melatonin's...
More research is required to understand how melatonin protects neurons. The study aimed to find out if and how long non-coding RNA (lncRNA) contributes to melatonin's ability to defend the hippocampus from HO-induced oxidative injury. LncRNAs related to oxidative injury were predicted by bioinformatics methods. Mouse hippocampus-derived neuronal HT22 cells were treated with HO with or without melatonin. Viability and apoptosis were detected by Cell Counting Kit-8 and Hoechst33258. RNA and protein levels were measured by quantitative real-time PCR, Western blot, and immunofluorescence. Bioinformatics predicted that 38 lncRNAs were associated with oxidative injury in mouse neurons. LncRNA nuclear paraspeckle assembly transcript 1 (NEAT1) was related to HO-induced oxidative injury and up-regulated by melatonin in HT22 cells. The knockdown of NEAT1 exacerbated HO-induced oxidative injury, weakened the moderating effect of melatonin, and abolished the increasing effect of melatonin on the mRNA and protein level of . Taken together, melatonin attenuates HO-induced oxidative injury by upregulating lncRNA NEAT1, which is essential for melatonin stabilizing the mRNA and protein level of for the survival of HT22 cells. The research may assist in the treatment of oxidative injury-induced hippocampal degeneration associated with aging using melatonin and its target lncRNA NEAT1.
Topics: Mice; Animals; RNA, Long Noncoding; Melatonin; Hydrogen Peroxide; Hippocampus; Apoptosis; Oxidative Stress; RNA, Messenger; MicroRNAs
PubMed: 36361683
DOI: 10.3390/ijms232112891 -
EMBO Reports Jan 2023Paraspeckles are subnuclear RNA-protein structures that are implicated in important processes including cellular stress response, differentiation, and cancer...
Paraspeckles are subnuclear RNA-protein structures that are implicated in important processes including cellular stress response, differentiation, and cancer progression. However, it is unclear how paraspeckles impart their physiological effect at the molecular level. Through biochemical analyses, we show that paraspeckles interact with the SWI/SNF chromatin-remodeling complex. This is specifically mediated by the direct interaction of the long-non-coding RNA NEAT1 of the paraspeckles with ARID1B of the cBAF-type SWI/SNF complex. Strikingly, ARID1B depletion, in addition to resulting in loss of interaction with the SWI/SNF complex, decreases the binding of paraspeckle proteins to chromatin modifiers, transcription factors, and histones. Functionally, the loss of ARID1B and NEAT1 influences the transcription and the alternative splicing of a common set of genes. Our findings reveal that dynamic granules such as the paraspeckles may leverage the specificity of epigenetic modifiers to impart their regulatory effect, thus providing a molecular basis for their function.
Topics: Paraspeckles; Transcription Factors; RNA, Long Noncoding; Chromatin Assembly and Disassembly; Chromatin
PubMed: 36354291
DOI: 10.15252/embr.202255345 -
Renal Failure Dec 2022Given the reported effects of nuclear paraspeckle assembly transcript 1 (NEAT1) on kidney injury, a study is worth formulating to investigate whether and how NEAT1...
BACKGROUND
Given the reported effects of nuclear paraspeckle assembly transcript 1 (NEAT1) on kidney injury, a study is worth formulating to investigate whether and how NEAT1 impacts podocytes.
MATERIALS AND METHODS
A mouse podocyte injury model was established using the adriamycin (ADR)-induced mouse podocyte cell line (MPC5). The target relationships between NEAT1 and microRNA (miR)-23b-3p and between miR-23b-3p and Bcl-2 interacting protein 3 like (BNIP3L) were verified by dual-luciferase reporter assay and RNA immunoprecipitation assay. After ADR-induced MPC5 cells were transfected with NEAT1 overexpression plasmid (oe-NEAT1) or shNEAT1, the viability and apoptosis of MPC5 cells were evaluated by Cell Counting Kit-8 (CCK-8) assay and flow cytometry, respectively. The expressions of MPC5, miR-23b-3p, BNIP3L and the factors related to podocyte injury, apoptosis and epithelial-mesenchymal transition were determined using quantitative real-time polymerase chain reaction (qRT-PCR) and Western blot.
RESULTS
NEAT1 was high-expressed in ADR-induced cell model. After transfection with oe-NEAT1, the expression of NEAT1, the levels of marker (Desmin) and apoptosis were promoted, while the viability and the levels of podocyte injury markers (WT1, Nephrin) were inhibited in ADR-induced cells. However, shNEAT1 generated the effects opposite to oe-NEAT1. Besides, miR-23b-3p competitively bound to NEAT1 and targeted BNIP3L. MiR-23b-3p inhibitor reversed the effect of shNEAT1, while its effect could be further offset by shBNIP3L. Furthermore, miR-23b-3p inhibitor affected mouse podocyte injury through downregulating Bcl-2 and E-cadherin levels and upregulating Cleaved-caspase-3, Bax, N-cadherin, Vimentin and Snail levels, but shBNIP3L did oppositely.
CONCLUSION
NEAT1 promotes the podocyte injury targeting miR-23b-3p/BNIP3L axis.
Topics: Animals; Mice; Apoptosis; MicroRNAs; Paraspeckles; Podocytes; Proto-Oncogene Proteins c-bcl-2; RNA, Long Noncoding
PubMed: 36350669
DOI: 10.1080/0886022X.2022.2091998 -
PloS One 2022The herpes simplex virus 1 (HSV-1) virion host shut-off (vhs) protein cleaves both cellular and viral mRNAs by a translation-initiation-dependent mechanism, which should...
The herpes simplex virus 1 (HSV-1) virion host shut-off (vhs) protein cleaves both cellular and viral mRNAs by a translation-initiation-dependent mechanism, which should spare circular RNAs (circRNAs). Here, we show that vhs-mediated degradation of linear mRNAs leads to an enrichment of circRNAs relative to linear mRNAs during HSV-1 infection. This was also observed in influenza A virus (IAV) infection, likely due to degradation of linear host mRNAs mediated by the IAV PA-X protein and cap-snatching RNA-dependent RNA polymerase. For most circRNAs, enrichment was not due to increased circRNA synthesis but due to a general loss of linear RNAs. In contrast, biogenesis of a circRNA originating from the long isoform (NEAT1_2) of the nuclear paraspeckle assembly transcript 1 (NEAT1) was induced both in HSV-1 infection-in a vhs-independent manner-and in IAV infection. This was associated with induction of novel linear splicing of NEAT1_2 both within and downstream of the circRNA. NEAT1_2 forms a scaffold for paraspeckles, nuclear bodies located in the interchromatin space, must likely remain unspliced for paraspeckle assembly and is up-regulated in HSV-1 and IAV infection. We show that NEAT1_2 splicing and up-regulation can be induced by ectopic co-expression of the HSV-1 immediate-early proteins ICP22 and ICP27, potentially linking increased expression and splicing of NEAT1_2. To identify other conditions with NEAT1_2 splicing, we performed a large-scale screen of published RNA-seq data. This uncovered both induction of NEAT1_2 splicing and poly(A) read-through similar to HSV-1 and IAV infection in cancer cells upon inhibition or knockdown of CDK7 or the MED1 subunit of the Mediator complex phosphorylated by CDK7. In summary, our study reveals induction of novel circular and linear NEAT1_2 splicing isoforms as a common characteristic of HSV-1 and IAV infection and highlights a potential role of CDK7 in HSV-1 or IAV infection.
Topics: Humans; Herpesvirus 1, Human; RNA, Circular; Immediate-Early Proteins; Influenza, Human; Herpes Simplex; RNA, Messenger; Protein Isoforms; RNA-Dependent RNA Polymerase; Mediator Complex
PubMed: 36279270
DOI: 10.1371/journal.pone.0276467 -
Journal of Oncology 2022(NEAT1) is commonly considered an oncogene in various cancers. The long noncoding RNA NEAT1 has been reported to be overexpressed in colorectal cancer (CRC). However,...
BACKGROUND
(NEAT1) is commonly considered an oncogene in various cancers. The long noncoding RNA NEAT1 has been reported to be overexpressed in colorectal cancer (CRC). However, the exact role of NEAT1 in CRC remains unknown. Our research aimed to explore the function of NEAT1 in the tumorigenesis and the development of CRC.
METHODS
Real-time quantitative PCR (qRT-PCR) was used to detect the NEAT1, miR-216b, and YIN-YANG-1 (YY1) mRNA levels in CRC tissues and cells, then immunohistochemistry (IHC) was used to detect the expression of YY1 in CRC tissues. Luciferase reporter, qPCR, western blot, and DNA pulldown assays were conducted to study the relationships between NEAT1, miR-216b, and YY1. Flow cytometry analysis was performed for cell cycle and apoptosis analyses, and a colony formation assay was performed to test cell proliferation. Transwell assays were performed to detect cell invasion and migration.
RESULTS
The NEAT1 expression was significantly upregulated in CRC tissues compared with its expression in normal tissues, and downregulation of NEAT1 suppressed the proliferation, migration, and invasion of CRC cells. Moreover, we found NEAT1 decreased the miR-216b level directly, and the suppression of miR-216b could inhibit the function of downstream YY1. However, overexpression of YY1 accelerated CRC cell proliferation, migration, and invasion.
CONCLUSION
Our results indicated that NEAT1 acted as an oncogene in CRC and promoted the progression of CRC by directly sponging miR-216 b expression to activate the expression of YY1. The NEAT1/miR-216b/YY1 axis may be a novel therapeutic target for CRC.
PubMed: 36262350
DOI: 10.1155/2022/8130132 -
Open Life Sciences 2022The study's purpose was to investigate the biological function of long non-coding RNA nuclear paraspeckle assembly transcript 1 (NEAT1) in hepatoma carcinoma (HCC). HCC...
The study's purpose was to investigate the biological function of long non-coding RNA nuclear paraspeckle assembly transcript 1 (NEAT1) in hepatoma carcinoma (HCC). HCC tissues and cells exhibited increased levels of NEAT1 and decreased levels of miR-125a-5p. Reduction in the expression of NEAT suppressed HepG2 cell proliferation and increased apoptosis. This was accompanied by suppression of the AKT/mTOR and ERK pathways, while the opposite was observed for miR-125a-5p. Angiogenesis assay results indicated that NEAT was proangiogenic. A dual-luciferase reporter assay indicated that NEAT1 was bound to miR-125a-5p and miR-125a-5p was bound to vascular endothelial growth factor (VEGF). The proangiogenic effects of NEAT and its stimulation of AKT/mTOR and ERK were reversed by miR-125a-5p. The anti-angiogenic effects of miR-125a-5p and its inhibitory effect on AKT/mTOR and ERK pathways were reversed by co-incubation with VEGF. The conclusion was that NEAT1 enhances angiogenesis in HCC by VEGF via a competing endogenous RNA (ceRNA) of miR-125a-5p that regulates AKT/mTOR and ERK pathways.
PubMed: 36213383
DOI: 10.1515/biol-2022-0498 -
The Journal of Biological Chemistry Nov 2022RNA-binding proteins of the DBHS (Drosophila Behavior Human Splicing) family, NONO, SFPQ, and PSPC1 have numerous roles in genome stability and transcriptional and...
RNA-binding proteins of the DBHS (Drosophila Behavior Human Splicing) family, NONO, SFPQ, and PSPC1 have numerous roles in genome stability and transcriptional and posttranscriptional regulation. Critical to DBHS activity is their recruitment to distinct subnuclear locations, for example, paraspeckle condensates, where DBHS proteins bind to the long noncoding RNA NEAT1 in the first essential step in paraspeckle formation. To carry out their diverse roles, DBHS proteins form homodimers and heterodimers, but how this dimerization influences DBHS localization and function is unknown. Here, we present an inducible GFP-NONO stable cell line and use it for live-cell 3D-structured illumination microscopy, revealing paraspeckles with dynamic, twisted elongated structures. Using siRNA knockdowns, we show these labeled paraspeckles consist of GFP-NONO/endogenous SFPQ dimers and that GFP-NONO localization to paraspeckles depends on endogenous SFPQ. Using purified proteins, we confirm that partner swapping between NONO and SFPQ occurs readily in vitro. Crystallographic analysis of the NONO-SFPQ heterodimer reveals conformational differences to the other DBHS dimer structures, which may contribute to partner preference, RNA specificity, and subnuclear localization. Thus overall, our study suggests heterodimer partner availability is crucial for NONO subnuclear distribution and helps explain the complexity of both DBHS protein and paraspeckle dynamics through imaging and structural approaches.
Topics: Humans; Dimerization; Paraspeckles; RNA-Binding Proteins; Gene Expression Regulation; RNA, Long Noncoding
PubMed: 36209820
DOI: 10.1016/j.jbc.2022.102563 -
Molecular Biology and Evolution Oct 2022Although new genes can arrive from modes other than duplication, few examples are well characterized. Given high expression in some human brain subregions and a putative...
Although new genes can arrive from modes other than duplication, few examples are well characterized. Given high expression in some human brain subregions and a putative link to psychological disorders [e.g., schizophrenia (SCZ)], suggestive of brain functionality, here we characterize piggyBac transposable element-derived 1 (PGBD1). PGBD1 is nonmonotreme mammal-specific and under purifying selection, consistent with functionality. The gene body of human PGBD1 retains much of the original DNA transposon but has additionally captured SCAN and KRAB domains. Despite gene body retention, PGBD1 has lost transposition abilities, thus transposase functionality is absent. PGBD1 no longer recognizes piggyBac transposon-like inverted repeats, nonetheless PGBD1 has DNA binding activity. Genome scale analysis identifies enrichment of binding sites in and around genes involved in neuronal development, with association with both histone activating and repressing marks. We focus on one of the repressed genes, the long noncoding RNA NEAT1, also dysregulated in SCZ, the core structural RNA of paraspeckles. DNA binding assays confirm specific binding of PGBD1 both in the NEAT1 promoter and in the gene body. Depletion of PGBD1 in neuronal progenitor cells (NPCs) results in increased NEAT1/paraspeckles and differentiation. We conclude that PGBD1 has evolved core regulatory functionality for the maintenance of NPCs. As paraspeckles are a mammal-specific structure, the results presented here show a rare example of the evolution of a novel gene coupled to the evolution of a contemporaneous new structure.
Topics: Animals; Cell Nucleus; DNA Transposable Elements; Histones; Humans; Mammals; Nerve Tissue Proteins; Paraspeckles; RNA, Long Noncoding; Transposases
PubMed: 36205081
DOI: 10.1093/molbev/msac175 -
Frontiers in Molecular Biosciences 2022In recent decades, a growing number of biomolecular condensates have been identified in eukaryotic cells. These structures form through phase separation and have been... (Review)
Review
In recent decades, a growing number of biomolecular condensates have been identified in eukaryotic cells. These structures form through phase separation and have been linked to a diverse array of cellular processes. While a checklist of established membrane-bound organelles is present across the eukaryotic domain, less is known about the conservation of membrane-less subcellular structures. Many of these structures can be seen throughout eukaryotes, while others are only thought to be present in metazoans or a limited subset of species. In particular, the nucleus is a hub of biomolecular condensates. Some of these subnuclear domains have been found in a broad range of organisms, which is a characteristic often attributed to essential functionality. However, this does not always appear to be the case. For example, the nucleolus is critical for ribosomal biogenesis and is present throughout the eukaryotic domain, while the Cajal bodies are believed to be similarly conserved, yet these structures are dispensable for organismal survival. Likewise, depletion of the omega speckles reduces viability, despite the apparent absence of this domain in higher eukaryotes. By reviewing primary research that has analyzed the presence of specific condensates (nucleoli, Cajal bodies, amyloid bodies, nucleolar aggresomes, nuclear speckles, nuclear paraspeckles, nuclear stress bodies, PML bodies, omega speckles, NUN bodies, mei2 dots) in a cross-section of organisms (e.g., human, mouse, , , yeast), we adopt a human-centric view to explore the emergence, retention, and absence of a subset of nuclear biomolecular condensates. This overview is particularly important as numerous biomolecular condensates have been linked to human disease, and their presence in additional species could unlock new and well characterized model systems for health research.
PubMed: 36203874
DOI: 10.3389/fmolb.2022.998363