scholarly journals circRNA N6-methyladenosine methylation in preeclampsia and the potential role of N6-methyladenosine-modified circPAPPA2 in trophoblast invasion

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Yonggang Zhang ◽  
Hongling Yang ◽  
Yan Long ◽  
Yipeng Zhang ◽  
Ronggui Chen ◽  
...  
Keyword(s):  
Rna Stability ◽  
Start Codon ◽  
Trophoblast Invasion ◽  
Reverse Transcription Pcr ◽  
Mrna Binding Protein ◽  
Rna Immunoprecipitation ◽  
New Vision ◽  
Mrna Binding

AbstractHere, we performed N6-methyladenosine (m6A) RNA sequencing to determine the circRNA m6A methylation changes in the placentas during the pathogenesis of preeclampsia (PE). We verified the expression of the circRNA circPAPPA2 using quantitative reverse transcription-PCR. An invasion assay was carried out to identify the role of circPAPPA2 in the development of PE. Mechanistically, we investigated the cause of the altered m6A modification of circPAPPA2 through overexpression and knockdown cell experiments, RNA immunoprecipitation, fluorescence in situ hybridization and RNA stability experiments. We found that increases in m6A-modified circRNAs are prevalent in PE placentas and that the main changes in methylation occur in the 3’UTR and near the start codon, implicating the involvement of these changes in PE development. We also found that the levels of circPAPPA2 are decreased but that m6A modification is augmented. Furthermore, we discovered that methyltransferase‑like 14 (METTL14) increases the level of circPAPPA2 m6A methylation and that insulin-like growth factor 2 mRNA-binding protein 3 (IGF2BP3) maintains circPAPPA2 stability. Decreases in IGF2BP3 levels lead to declines in circPAPPA2 levels. In summary, we provide a new vision and strategy for the study of PE pathology and report that placental circRNA m6A modification appears to be an important regulatory mechanism.

scholarly journals GRK2-Dependent HuR Phosphorylation Regulates HIF1α Activation under Hypoxia or Adrenergic Stress

Cancers ◽  
2020 ◽  
Vol 12 (5) ◽  
pp. 1216
Author(s):  
Clara Reglero ◽  
Vanesa Lafarga ◽  
Verónica Rivas ◽  
Ángela Albitre ◽  
Paula Ramos ◽  
...  
Keyword(s):  
Hypoxia Inducible Factor ◽  
Luminal Breast Cancer ◽  
Adaptation To Hypoxia ◽  
Receptor Kinase ◽  
Breast Cancer Patients ◽  
Mrna Binding Protein ◽  
Relevant Role ◽  
Mrna Binding ◽  
G Protein Coupled

Adaptation to hypoxia is a common feature in solid tumors orchestrated by oxygen-dependent and independent upregulation of the hypoxia-inducible factor-1α (HIF-1α). We unveiled that G protein-coupled receptor kinase (GRK2), known to be overexpressed in certain tumors, fosters this hypoxic pathway via phosphorylation of the mRNA-binding protein HuR, a central HIF-1α modulator. GRK2-mediated HuR phosphorylation increases the total levels and cytoplasmic shuttling of HuR in response to hypoxia, and GRK2-phosphodefective HuR mutants show defective cytosolic accumulation and lower binding to HIF-1α mRNA in hypoxic Hela cells. Interestingly, enhanced GRK2 and HuR expression correlate in luminal breast cancer patients. GRK2 also promotes the HuR/HIF-1α axis and VEGF-C accumulation in normoxic MCF7 breast luminal cancer cells and is required for the induction of HuR/HIF1-α in response to adrenergic stress. Our results point to a relevant role of the GRK2/HuR/HIF-1α module in the adaptation of malignant cells to tumor microenvironment-related stresses.

scholarly journals Expression of the pyr Operon of Lactobacillus plantarum Is Regulated by Inorganic Carbon Availability through a Second Regulator, PyrR2, Homologous to the Pyrimidine-Dependent Regulator PyrR1

2006 ◽  
Vol 188 (24) ◽  
pp. 8607-8616 ◽  
Author(s):  
Florence Arsène-Ploetze ◽  
Valérie Kugler ◽  
Jan Martinussen ◽  
Françoise Bringel
Keyword(s):  
Lactobacillus Plantarum ◽  
Inorganic Carbon ◽  
Rna Binding ◽  
Rna Stability ◽  
Gene Replacement ◽  
Amino Acid Identity ◽  
Reverse Transcription Pcr ◽  
Phenotype Analysis ◽  
High Concentrations

ABSTRACT Inorganic carbon (IC), such as bicarbonate or carbon dioxide, stimulates the growth of Lactobacillus plantarum. At low IC levels, one-third of natural isolated L. plantarum strains are nutritionally dependent on exogenous arginine and pyrimidine, a phenotype previously defined as high-CO2-requiring (HCR) prototrophy. IC enrichment significantly decreased the amounts of the enzymes in the pyrimidine biosynthetic pathway encoded by the pyrR 1 BCAa 1 Ab 1 DFE operon, as demonstrated by proteomic analysis. Northern blot and reverse transcription-PCR experiments demonstrated that IC levels regulated pyr genes mainly at the level of transcription or RNA stability. Two putative PyrR regulators with 62% amino acid identity are present in the L. plantarum genome. PyrR1 is an RNA-binding protein that regulates the pyr genes in response to pyrimidine availability by a mechanism of transcriptional attenuation. In this work, the role of PyrR2 was investigated by allelic gene replacement. Unlike the pyrR 1 mutant, the ΔpyrR 2 strain acquired a demand for both pyrimidines and arginine unless bicarbonate or CO2 was present at high concentrations, which is known as an HCR phenotype. Analysis of the IC- and pyrimidine-mediated regulation in pyrR 1 and pyrR 2 mutants suggested that only PyrR2 positively regulates the expression levels of the pyr genes in response to IC levels but had no effect on pyrimidine-mediated repression. A model is proposed for the respective roles of PyrR1 and PyrR2 in the pyr regulon expression.

scholarly journals LncRNA AC245100.4 binds HSP90 to promote the proliferation of prostate cancer

Epigenomics ◽  
2020 ◽  
Vol 12 (15) ◽  
pp. 1257-1271
Author(s):  
Rongjun Cui ◽  
Chi Liu ◽  
Ping Lin ◽  
Hui Xie ◽  
Wei Wang ◽  
...  
Keyword(s):  
Prostate Cancer ◽  
Cell Counting ◽  
Chaperone Function ◽  
In Vivo Assays ◽  
Iκb Kinase ◽  
Rna Immunoprecipitation ◽  
The Stability

Aim: To investigate the role and mechanisms of AC245100.4 in prostate cancer. Materials & methods: The expression and location of AC245100.4 were examined using real-time PCR and  in situ hybridization. Cell Counting Kit-8, clone formation, flow cytometry and in vivo assays were conducted to determine the role of AC245100.4. RNA antisense purification with mass spectrometry and RNA immunoprecipitation were performed to identify proteins that bind to AC245100.4. Western blotting was performed to quantify the expression of protein. Results: AC245100.4 expression was upregulated in prostate cancer and mainly located in the cytoplasm. Knockdown of AC245100.4 inhibited proliferation of prostate cancer. Mechanistically, AC245100.4 bound to HSP90 and altered its chaperone function, increased the stability of IκB kinase and activated the NFκB signaling pathway. Conclusion: AC245100.4 promotes the proliferation of prostate cancer via binding of HSP90.

scholarly journals CLUH regulates mitochondrial biogenesis by binding mRNAs of nuclear-encoded mitochondrial proteins

2014 ◽  
Vol 207 (2) ◽  
pp. 213-223 ◽  
Author(s):  
Jie Gao ◽  
Désirée Schatton ◽  
Paola Martinelli ◽  
Henriette Hansen ◽  
David Pla-Martin ◽  
...  
Keyword(s):  
Mitochondrial Biogenesis ◽  
Mitochondrial Proteins ◽  
Control Mechanisms ◽  
Messenger Ribonucleic Acid ◽  
Mrna Binding Protein ◽  
Protein Biogenesis ◽  
Genes Encoding ◽  
Rna Immunoprecipitation ◽  
Tyrosinated Tubulin ◽  
Mrna Binding

Mitochondrial function requires coordination of two genomes for protein biogenesis, efficient quality control mechanisms, and appropriate distribution of the organelles within the cell. How these mechanisms are integrated is currently not understood. Loss of the Clu1/CluA homologue (CLUH) gene led to clustering of the mitochondrial network by an unknown mechanism. We find that CLUH is coregulated both with genes encoding mitochondrial proteins and with genes involved in ribosomal biogenesis and translation. Our functional analysis identifies CLUH as a cytosolic messenger ribonucleic acid (RNA; mRNA)–binding protein. RNA immunoprecipitation experiments followed by next-generation sequencing demonstrated that CLUH specifically binds a subset of mRNAs encoding mitochondrial proteins. CLUH depletion decreased the levels of proteins translated by target transcripts and caused mitochondrial clustering. A fraction of CLUH colocalizes with tyrosinated tubulin and can be detected close to mitochondria, suggesting a role in regulating transport or translation of target transcripts close to mitochondria. Our data unravel a novel mechanism linking mitochondrial biogenesis and distribution.

scholarly journals A novel lncRNA SOX2OT promotes the malignancy of human colorectal cancer by interacting with miR-194-5p/SOX5 axis

2021 ◽  
Vol 12 (5) ◽  
Author(s):  
Ye Feng ◽  
Ying Xu ◽  
Yongjian Gao ◽  
Yiying Chen ◽  
Xuefeng Wang ◽  
...  
Keyword(s):  
Colorectal Cancer ◽  
Luciferase Reporter ◽  
Migration And Invasion ◽  
Loss Of Function ◽  
Functional Relationships ◽  
Rna Immunoprecipitation ◽  
Proliferation And Metastasis

AbstractLong noncoding RNAs (lncRNAs) show emerging roles in colorectal cancer (CRC) development and are considered to be involved in the potential mechanism of tumor malignancy. While Sox2 overlapping transcript (SOX2OT) has been implicated in the progression of multiple cancers, its role in CRC remains to be explored. In this study, in situ hybridization (ISH) and qRT-PCR were performed to establish the functional relationships between SOX2OT and CRC deranged in CRC tissue and cells. Subsequently, SOX2OT shRNAs vectors were transfected into CRC cells to performed loss-of-function assays to detect the potential role of SOX2OT on proliferation and metastasis in vitro and vivo. The results showed SOX2OT was an oncogene that was up-regulated in human CRC tissues and cell lines. SOX2OT silencing suppressed cell proliferation, migration, and invasion in CRC cells in vitro, and inhibited tumorigenesis in the mouse xenografts. Bioinformatic predictive analysis coupled with the dual-luciferase reporter, RNA immunoprecipitation (RIP), and functional rescue assay elucidated the mechanistic network of the SOX2OT-miR-194-5p-SOX5 axis in CRC. Mechanistically, SOX2OT acted as a competing endogenous RNA (ceRNA) to upregulate SOX5 by sponging miR-194-5p. Downregulated SOX2OT boosted miR-194-5p expression, thus decreased the protein level of SOX5, which suppresses tumorgenesis of CRC.

scholarly journals METTL3 Promotes Lung Adenocarcinoma Tumorigenesis and Inhibits Ferroptosis by Stabilizing SLC7A11 m6A Modification

2021 ◽  
Author(s):  
Yiming Xu ◽  
Dandan Lv ◽  
Chao Yan ◽  
Hua Su ◽  
Xue Zhang ◽  
...  
Keyword(s):  
Cell Proliferation ◽  
Lung Adenocarcinoma ◽  
Rna Stability ◽  
Underlying Mechanism ◽  
Rna Immunoprecipitation ◽  
Direct Target ◽  
Novel Target

Abstract Background: N6-methyladenosine (m 6 A) has emerged as a significant regulator of the progress of various cancers. However, its role in lung adenocarcinoma (LUAD) remains unclear. Here, we explored the biological function and underlying mechanism of methyltransferase-like 3 (METTL3), the main catalyst of m 6 A, in LUAD progression. Methods: The expression of m 6 A, METTL3, YTHDF1 and SLC7A11 were detected by immunochemistry or/and online datasets in LUAD patients. The effects of METTL3 on LUAD cell proliferation, apoptosis and ferroptosis were assessed through in vitro loss-and gain-of-function experiments. The in vivo effect on tumorigenesis of METTL3 was evaluated using the LUAD cell xenograft mouse model. MeRIP-seq, RNA immunoprecipitation and RNA stability assay were conducted to explore the molecular mechanism of METTL3 in LUAD. Results: The results showed that the m 6 A level, as well as the methylase METTL3 were both significantly elevated in LUAD patients and lung cancer cells. Functionally, we found that METTL3 could promote proliferation and inhibit ferroptosis in different LUAD cell models, while METTL3 knockdown suppressed LUAD growth in cell-derived xenografts. Mechanistically, solute carrier 7A11 (SLC7A11), the subunit of system Xc - , was identified as the direct target of METTL3 by mRNA-seq and MeRIP-seq. METTL3-mediated m 6 A modification could stabilize SLC7A11 mRNA and promote its translation, thus promoting LUAD cell proliferation and inhibiting cell ferroptosis, a novel form of programmed cell death. Additionally, we demonstrated that YTHDF1, a m 6 A reader, was recruited by METTL3 to enhance SLC7A11 m 6 A modification. Moreover, the expression of YTHDF1 and SLC7A11 were positively correlated with METTL3 and m 6 A in LUAD tissues.Conclusions: These findings reinforced the oncogenic role of METTL3 in LUAD progression and revealed its underlying correlation with cancer cell ferroptosis; these findings also indicate that METTL3 is a promising novel target in LUAD diagnosis and therapy.

scholarly journals Endothelin A Receptor Blockade Prevents Capillary/Myocyte Mismatch in the Heart of Uremic Animals

2000 ◽  
Vol 11 (9) ◽  
pp. 1702-1711 ◽  
Author(s):  
KERSTIN AMANN ◽  
KLAUS MÜNTER ◽  
SABINE WESSELS ◽  
JÜRGEN WAGNER ◽  
VITALI BALAJEW ◽  
...  
Keyword(s):  
Receptor Antagonist ◽  
Reverse Transcription ◽  
Left Ventricular ◽  
Capillary Length ◽  
Subtotal Nephrectomy ◽  
Reverse Transcription Pcr ◽  
Endothelin A Receptor ◽  
Immunohistochemical Studies

Abstract.In the heart of uremic animals and patients, the number of capillaries per volume of myocardium is reduced. Immunohistochemical studies demonstrated increased cardiac endothelin-1 (ET-1) expression in the left ventricle of uremic animals. Therefore, whether treatment with a selective ETA-receptor antagonist prevented such capillary-myocyte mismatch was investigated. Twenty-four h after subtotal nephrectomy, rats were left untreated or started on treatment with the ETA-receptor antagonist LU 135252 (20 mg/kg per d) and with the angiotensin-converting enzyme (ACE) inhibitor trandolapril (0.3 mg/kg per d), respectively. BP was monitored by telemetry. Myocardial capillary length density was analyzed by stereologic techniques that avoid anisotropy artifacts. In addition, cardiac ET-1 protein and mRNA were measured using immunohistochemistry,in situhybridization, and quantitative reverse transcription—PCR. Changes in cardiac ETA-and ETB-PCR. receptor mRNA were measured using reverse transcription—PCR. Fifteen wk after subtotal nephrectomy, significantly reduced left ventricular capillary length density (3307 ± 535 mm/mm3) was found compared with sham-operated controls (3995 ± 471 mm/mm3); this was also seen in animals that were treated with trandolapril (3503 ± 533 mm/mm3) but not in animals that were treated with LU 135252 (3800 ± 303 mm/mm3). The results support a role of ET-1 in the genesis of left ventricular capillary/myocyte mismatch in uremia.

scholarly journals Regulation of LH Receptor mRNA Binding Protein by miR-122 in Rat Ovaries

Endocrinology ◽  
2013 ◽  
Vol 154 (12) ◽  
pp. 4826-4834 ◽  
Author(s):  
Bindu Menon ◽  
Jennifer Sinden ◽  
Meghan Franzo-Romain ◽  
Raman Bhadradri Botta ◽  
K. M. J. Menon
Keyword(s):  
Nucleic Acid ◽  
Mrna Expression ◽  
Signaling Pathways ◽  
Binding Protein ◽  
Locked Nucleic Acid ◽  
Down Regulation ◽  
Lh Receptor ◽  
Mrna Binding Protein ◽  
Mrna Binding

LH receptor (LHR) expression in the ovary is regulated by the RNA binding protein, (LHR mRNA binding protein [LRBP]), which has been identified as being mevalonate kinase. This study examined the role of microRNA miR-122 in LRBP-mediated LHR mRNA expression. Real-time PCR analysis of ovaries from pregnant mare serum gonadotropin/human chorionic gonadotropin (hCG)-primed female rats treated with hCG to down-regulate LHR expression showed that an increase in miR-122 expression preceded LHR mRNA down-regulation. The expression of miR-122 and its regulation was confirmed using fluorescent in situ hybridization of the frozen ovary sections using 5′-fluorescein isothiocyanate-labeled miR-122 locked nucleic acid probe. The increased expression of miR-122 preceded increased expression of LRBP mRNA and protein, and these increases were followed by LHR mRNA down-regulation. Inhibition of protein kinase A (PKA) and ERK1/2 signaling pathways by H89 and UO126, respectively, attenuated the hCG-mediated up-regulation of miR-122 levels. This was also confirmed in vitro using human granulosa cells. These results suggest the possibility that hCG-mediated miR-122 expression is mediated by the activation of cAMP/PKA/ERK signaling pathways. Inhibition of miR-122 by injection of the locked nucleic acid-conjugated antagomir of miR-122 abrogated the hCG-mediated increases in LRBP protein expression. Because it has been previously shown that miR-122 regulates sterol regulatory element-binding proteins (SREBPs) and SREBPs, in turn, regulate LRBP expression, the role of SREBPs in miR-122-mediated increase in LRBP expression was then examined. The levels of active forms of both SREBP-1a and SREBP-2 were increased in response to hCG treatment, and the stimulatory effect was sustained up to 4 hours. Taken together, our results suggest that hCG-induced down-regulation of LHR mRNA expression is mediated by activation of cAMP/PKA/ERK pathways to increase miR-122 expression, which then increases LRBP expression through the activation of SREBPs.

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