scholarly journals Posttranscriptional Regulation of Chicken ccn2 Gene Expression by Nucleophosmin/B23 during Chondrocyte Differentiation

2008 ◽  
Vol 28 (19) ◽  
pp. 6134-6147 ◽  
Author(s):  
Yoshiki Mukudai ◽  
Satoshi Kubota ◽  
Harumi Kawaki ◽  
Seiji Kondo ◽  
Takanori Eguchi ◽  
...  
Keyword(s):  
Mrna Stability ◽  
Posttranscriptional Regulation ◽  
Transcriptional Level ◽  
Chondrocyte Differentiation ◽  
Cofactor Binding ◽  
Chimeric Rnas ◽  
Cytosolic Extract ◽  
Embryonic Fibroblast

ABSTRACT CCN2/CTGF is a multifunctional factor that plays a crucial role in the growth and differentiation of chondrocytes. The chicken ccn2 gene is regulated not only at the transcriptional level but also by the interaction between a posttranscriptional element in the 3′ untranslated region (3′-UTR) and a cofactor. In the present study, we identified a nucleophosmin (NPM) (also called B23) as this cofactor. Binding of NPM to the element was confirmed, and subsequent analysis revealed a significant correlation between the decrease in cytosolic NPM and the increased stability of the ccn2 mRNA during chondrocyte differentiation in vivo. Furthermore, recombinant chicken NPM enhanced the degradation of chimeric RNAs containing the posttranscriptional cis elements in a chicken embryonic fibroblast extract in vitro. It is noteworthy that the RNA destabilization effect by NPM was far more prominent in the cytosolic extract of chondrocytes than in that of fibroblasts, representing a chondrocyte-specific action of NPM. Stimulation by growth factors to promote differentiation changed the subcellular distribution of NPM in chondrocytes, which followed the expected patterns from the resultant change in the ccn2 mRNA stability. Therefore, the present study reveals a novel aspect of NPM as a key player in the posttranscriptional regulation of ccn2 mRNA during the differentiation of chondrocytes.

scholarly journals Aberrantly high activation of a FoxM1–STMN1 axis contributes to progression and tumorigenesis in FoxM1-driven cancers

2021 ◽  
Vol 6 (1) ◽  
Author(s):  
Jun Liu ◽  
Jipeng Li ◽  
Ke Wang ◽  
Haiming Liu ◽  
Jianyong Sun ◽  
...  
Keyword(s):  
Cell Proliferation ◽  
Poor Prognosis ◽  
Soft Agar ◽  
Transcriptional Level ◽  
Regulation Mechanism ◽  
Strong Positive Correlation ◽  
Cell Viability Assay ◽  
High Level

AbstractFork-head box protein M1 (FoxM1) is a transcriptional factor which plays critical roles in cancer development and progression. However, the general regulatory mechanism of FoxM1 is still limited. STMN1 is a microtubule-binding protein which can inhibit the assembly of microtubule dimer or promote depolymerization of microtubules. It was reported as a major responsive factor of paclitaxel resistance for clinical chemotherapy of tumor patients. But the function of abnormally high level of STMN1 and its regulation mechanism in cancer cells remain unclear. In this study, we used public database and tissue microarrays to analyze the expression pattern of FoxM1 and STMN1 and found a strong positive correlation between FoxM1 and STMN1 in multiple types of cancer. Lentivirus-mediated FoxM1/STMN1-knockdown cell lines were established to study the function of FoxM1/STMN1 by performing cell viability assay, plate clone formation assay, soft agar assay in vitro and xenograft mouse model in vivo. Our results showed that FoxM1 promotes cell proliferation by upregulating STMN1. Further ChIP assay showed that FoxM1 upregulates STMN1 in a transcriptional level. Prognostic analysis showed that a high level of FoxM1 and STMN1 is related to poor prognosis in solid tumors. Moreover, a high co-expression of FoxM1 and STMN1 has a more significant correlation with poor prognosis. Our findings suggest that a general FoxM1-STMN1 axis contributes to cell proliferation and tumorigenesis in hepatocellular carcinoma, gastric cancer and colorectal cancer. The combination of FoxM1 and STMN1 can be a more precise biomarker for prognostic prediction.

scholarly journals Phosphorylation of Serine 303 Is a Prerequisite for the Stress-Inducible SUMO Modification of Heat Shock Factor 1

2003 ◽  
Vol 23 (8) ◽  
pp. 2953-2968 ◽  
Author(s):  
Ville Hietakangas ◽  
Johanna K. Ahlskog ◽  
Annika M. Jakobsson ◽  
Maria Hellesuo ◽  
Niko M. Sahlberg ◽  
...  
Keyword(s):  
Heat Shock ◽  
Phosphorylation Site ◽  
Stress Granules ◽  
Heat Shock Factor ◽  
Transcriptional Level ◽  
Heat Shock Factor 1 ◽  
Protection Mechanism ◽  
Sumo Modification

ABSTRACT The heat shock response, which is accompanied by a rapid and robust upregulation of heat shock proteins (Hsps), is a highly conserved protection mechanism against protein-damaging stress. Hsp induction is mainly regulated at transcriptional level by stress-inducible heat shock factor 1 (HSF1). Upon activation, HSF1 trimerizes, binds to DNA, concentrates in the nuclear stress granules, and undergoes a marked multisite phosphorylation, which correlates with its transcriptional activity. In this study, we show that HSF1 is modified by SUMO-1 and SUMO-2 in a stress-inducible manner. Sumoylation is rapidly and transiently enhanced on lysine 298, located in the regulatory domain of HSF1, adjacent to several critical phosphorylation sites. Sumoylation analyses of HSF1 phosphorylation site mutants reveal that specifically the phosphorylation-deficient S303 mutant remains devoid of SUMO modification in vivo and the mutant mimicking phosphorylation of S303 promotes HSF1 sumoylation in vitro, indicating that S303 phosphorylation is required for K298 sumoylation. This finding is further supported by phosphopeptide mapping and analysis with S303/7 phosphospecific antibodies, which demonstrate that serine 303 is a target for strong heat-inducible phosphorylation, corresponding to the inducible HSF1 sumoylation. A transient phosphorylation-dependent colocalization of HSF1 and SUMO-1 in nuclear stress granules provides evidence for a strictly regulated subnuclear interplay between HSF1 and SUMO.

scholarly journals Direct repeats bind the EcR/USP receptor and mediate ecdysteroid responses in Drosophila melanogaster.

1996 ◽  
Vol 16 (6) ◽  
pp. 2977-2986 ◽  
Author(s):  
C Antoniewski ◽  
B Mugat ◽  
F Delbac ◽  
J A Lepesant
Keyword(s):  
Fat Body ◽  
Cell Transformation ◽  
Direct Repeat ◽  
Transgenic Animals ◽  
Transcriptional Level ◽  
Regulatory Sequences ◽  
Direct Repeats ◽  
Fbp1 Gene

The steroid hormone 20-hydroxyecdysone plays a key role in the induction and modulation of morphogenetic events throughout Drosophila development. Previous studies have shown that a heterodimeric nuclear receptor composed of the EcR and USP proteins mediates the action of the hormone at the transcriptional through binding to palindromic ecdysteroid mediates the action of the hormone at the transcriptional level through binding to palindromic ecdysteroid response elements (EcREs) such as those present in the promoter of the hsp27 gene or the fat body-specific enhancer of the Fbp1 gene. We show that in addition to palindromic EcREs, the EcR/USP heterodimer can bind in vitro with various affinities to direct repetitions of the motif AGGTCA separated by 1 to 5 nucleotides (DR1 to DR5), which are known to be target sites for vertebrate nuclear receptors. At variance with the receptors, EcR/USP was also found to bind to a DR0 direct repeat with no intervening nucleotide. In cell transformation assays, direct repeats DR0 to DR5 alone can render the minimum viral tk or Drosophila Fbp1 promoter responsive to 20-hydroxyecdysone, as does the palindromic hsp27 EcRE. In a transgenic assay, however, neither the palindromic hsp27 element nor direct repeat DR3 alone can make the Fbp1 minimal promoter responsive to premetamorphic ecdysteroid peaks. In contrast, DR0 and DR3 elements, when substituted for the natural palindromic EcRE in the context of the Fbp1 enhancer, can drive a strong fat body-specific ecdysteroid response in transgenic animals. These results demonstrate that directly repeated EcR/USP binding sites are as effective as palindromic EcREs in vivo. They also provide evidence that additional flanking regulatory sequences are crucially required to potentiate the hormonal response mediated by both types of elements and specify its spatial and temporal pattern.

scholarly journals A dynamic equilibrium between TTP and CPEB4 controls mRNA stability and inflammation resolution

2021 ◽  
Author(s):  
Clara Suñer ◽  
Annarita Sibilio ◽  
Judit Martín ◽  
Chiara Lara Castellazzi ◽  
Oscar Reina ◽  
...  
Keyword(s):  
Inflammatory Response ◽  
Mrna Stability ◽  
Regulatory Network ◽  
Dynamic Equilibrium ◽  
Relative Number ◽  
Mapk Signalling Pathway ◽  
Mapk Signalling ◽  
Inflammation Resolution

SUMMARYTemporal control of inflammation is critical to avoid pathological developments, and is largely defined through the differential stabilities of mRNAs. While TTP-directed mRNA deadenylation is known to destabilize ARE-containing mRNAs, this mechanism alone cannot explain the variety of mRNA expression kinetics observed during inflammation resolution. Here we show that inflammation resolution requires CPEB4 expression, in vitro and in vivo. Our results identify that CPEB4-directed polyadenylation and TTP-mediated deadenylation compete during the resolutive phase of the LPS response to uncouple the degradation of pro-inflammatory mRNAs from the sustained expression of anti-inflammatory mRNAs. The outcome of this equilibrium is quantitatively defined by the relative number of CPEs and AREs in each mRNA, and further shaped by the coordinated regulation by the MAPK signalling pathway of the levels and activities of their trans-acting factors, CPEB4 and TTP. Altogether, we describe a temporal- and transcript-specific regulatory network controlling the extent of the inflammatory response.

scholarly journals AUF-1 and YB-1 are critical determinants of β-globin mRNA expression in erythroid cells

Blood ◽  
2012 ◽  
Vol 119 (4) ◽  
pp. 1045-1053 ◽  
Author(s):  
Sebastiaan van Zalen ◽  
Grace R. Jeschke ◽  
Elizabeth O. Hexner ◽  
J. Eric Russell
Keyword(s):  
Posttranscriptional Regulation ◽  
Rna Binding ◽  
Globin Gene ◽  
K562 Cells ◽  
Erythroid Cells ◽  
Erythroid Progenitors ◽  
Globin Mrna ◽  
Affinity Enrichment

Abstract The normal accumulation of β-globin protein in terminally differentiating erythroid cells is critically dependent on the high stability of its encoding mRNA. The molecular basis for this property, though, is incompletely understood. Factors that regulate β-globin mRNA within the nucleus of early erythroid progenitors are unlikely to account for the constitutively high half-life of β-globin mRNA in the cytoplasm of their anucleate erythroid progeny. We conducted in vitro protein-RNA binding analyses that identified a cytoplasm-restricted β-globin messenger ribonucleoprotein (mRNP) complex in both cultured K562 cells and erythroid-differentiated human CD34+ cells. This novel mRNP targets a specific guanine-rich pentanucleotide in a region of the β-globin 3′untranslated region that has recently been implicated as a determinant of β-globin mRNA stability. Subsequent affinity-enrichment analyses identified AUF-1 and YB-1, 2 cytoplasmic proteins with well-established roles in RNA biology, as trans-acting components of the mRNP. Factor-depletion studies conducted in vivo demonstrated the importance of the mRNP to normal steady-state levels of β-globin mRNA in erythroid precursors. These data define a previously unrecognized mechanism for the posttranscriptional regulation of β-globin mRNA during normal erythropoiesis, providing new therapeutic targets for disorders of β-globin gene expression.

scholarly journals One Small RNA of Fusarium graminearum Targets and Silences CEBiP Gene in Common Wheat

2019 ◽  
Vol 7 (10) ◽  
pp. 425 ◽  
Author(s):  
Jiao Jian ◽  
Xu Liang
Keyword(s):  
Fusarium Graminearum ◽  
Small Rna ◽  
Pathogenic Fungus ◽  
Effective Means ◽  
Transcriptional Level ◽  
Head Blight ◽  
Protein Coding ◽  
Pathogen Invasion

The pathogenic fungus Fusarium graminearum (F. graminearum), causing Fusarium head blight (FHB) or scab, is one of the most important cereal killers worldwide, exerting great economic and agronomic losses on global grain production. To repress pathogen invasion, plants have evolved a sophisticated innate immunity system for pathogen recognition and defense activation. Simultaneously, pathogens continue to evolve more effective means of invasion to conquer plant resistance systems. In the process of co-evolution of plants and pathogens, several small RNAs (sRNAs) have been proved in regulating plant immune response and plant-microbial interaction. In this study, we report that a F. graminearum sRNA (Fg-sRNA1) can suppress wheat defense response by targeting and silencing a resistance-related gene, which codes a Chitin Elicitor Binding Protein (TaCEBiP). Transcriptional level evidence indicates that Fg-sRNA1 can target TaCEBiP mRNA and trigger silencing of TaCEBiP in vivo, and in Nicotiana benthamiana (N. benthamiana) plants, Western blotting experiments and YFP Fluorescence observation proofs show that Fg-sRNA1 can suppress the accumulation of protein coding by TaCEBiP gene in vitro. F. graminearum PH-1 strain displays a weakening ability to invasion when Barley stripe mosaic virus (BSMV) vector induces effective silencing Fg-sRNA1 in PH-1 infected wheat plants. Taken together, our results suggest that a small RNA from F. graminearum can target and silence the wheat TaCEBiP gene to enhance invasion of F. graminearum.

scholarly journals Tristetraprolin regulates IL-8 mRNA stability in cystic fibrosis lung epithelial cells

2009 ◽  
Vol 296 (6) ◽  
pp. L1012-L1018 ◽  
Author(s):  
Nagaraja Sethuraman Balakathiresan ◽  
Sharmistha Bhattacharyya ◽  
Usha Gutti ◽  
Robert P. Long ◽  
Catherine Jozwik ◽  
...  
Keyword(s):  
Cystic Fibrosis ◽  
Epithelial Cells ◽  
Mrna Stability ◽  
Posttranscriptional Regulation ◽  
Lung Epithelial Cells ◽  
Cellular Phenotype ◽  
Lung Epithelial ◽  
Vitro Analysis ◽  
In Vitro Analysis

Cystic fibrosis (CF) is due to mutations in the CFTR gene and is characterized by hypersecretion of the proinflammatory chemokine IL-8 into the airway lumen. Consequently, this induces the highly inflammatory cellular phenotype typical of CF. Our initial studies revealed that IL-8 mRNA is relatively stable in CF cells compared with those that had been repaired with [WT]CFTR (wild-type CFTR). Relevantly, the 3′-UTR of IL-8 mRNA contains AU-rich sequences (AREs) that have been shown to mediate posttranscriptional regulation of proinflammatory genes upon binding to ARE-binding proteins including Tristetraprolin (TTP). We therefore hypothesized that very low endogenous levels of TTP in CF cells might be responsible for the relative stability of IL-8 mRNA. As predicted, increased expression of TTP in CF cells resulted in reduced stability of IL-8 mRNA. An in vitro analysis of IL-8 mRNA stability in CF cells also revealed a TTP-induced enhancement of deadenylation causing reduction of IL-8 mRNA stability. We conclude that enhanced stability of IL-8 mRNA in TTP-deficient CF lung epithelial cells serve to drive the proinflammatory cellular phenotype in the CF lung.

scholarly journals Regulation of Translational Efficiency by Disparate5′-UTRs of PPARγSplice Variants

PPAR Research ◽  
2009 ◽  
Vol 2009 ◽  
pp. 1-8 ◽  
Author(s):  
Shawn McClelland ◽  
Roopali Shrivastava ◽  
Jheem D. Medh
Keyword(s):  
Secondary Structure ◽  
Posttranscriptional Regulation ◽  
Protein A ◽  
Firefly Luciferase ◽  
Translational Efficiency ◽  
Protein Levels ◽  
Gene Assay ◽  
Firefly Luciferase Gene

The PPAR-γgene encodes for at least 7 unique transcripts due to alternative splicing of five exons in the5′-untranslated region (UTR). The translated region is encoded by exons 1–6, which are identical in all isoforms. This study investigated the role of the5′-UTR in regulating the efficiency with which the message is translated to protein. A coupledin vitrotranscription-translation assay demonstrated that PPAR-γ1, -γ2, and -γ5 are efficiently translated, whereas PPAR-γ4 and -γ7 are poorly translated. Anin vivoreporter gene assay using each5′-UTR upstream of the firefly luciferase gene showed that the5′-UTRs for PPAR-γ1, -γ2, and -γ4 enhanced translation, whereas the5′-UTRs for PPAR-γ5 and -γ7 inhibited translation. Models of RNA secondary structure, obtained by the mfold software, were used to explain the mechanism of regulation by each5′-UTR. In general, it was found that the translational efficiency was inversely correlated with the stability of the mRNA secondary structure, the presence of base-pairing in the consensus Kozak sequence, the number of start codons in the5′-UTR, and the length of the5′-UTR. A better understanding of posttranscriptional regulation of translation will allow modulation of protein levels without altering transcription.

177. A MECHANISM UNDERLYING DISORDERS OF SEX DEVELOPMENT CAUSED BY DAX1 DUPLICATION

2009 ◽  
Vol 21 (9) ◽  
pp. 95
Author(s):  
L. Ludbrook ◽  
R. Sekido ◽  
R. Lovell-Badge ◽  
V. Harley
Keyword(s):  
Sex Determination ◽  
Disorders Of Sex Development ◽  
Nuclear Hormone Receptor ◽  
Testicular Development ◽  
Transcriptional Level ◽  
Sox9 Expression ◽  
Transgenic Mouse Line ◽  
Sex Development

The DAX1 protein is an orphan nuclear hormone receptor expressed in developing and adult hypothalamic, pituitary, adrenal and gonadal tissues. In humans, duplication of the DAX1 gene at locus Xp21 causes Disorders of Sex Development (DSD), whereby XY individuals develop as females, due to the failure of testicular development. DAX1 acts as a co-factor for nuclear receptor-mediated transcription of steroidogenic genes. In mice, overexpression of a Dax1 transgene causes delayed testis cord formation, a milder phenotype than that seen in human (1). Exactly how DAX1 duplication interferes with typical testicular development is unclear but a ‘window' of DAX1 activity was proposed (2). In order to identify the mechanism of DAX1 action when overexpressed in the developing XY gonad, we have used both in vivo and in vitro approaches. We hypothesised that, when present in excess, DAX1 must repress the action of early testis-forming genes. We investigated the effect of Dax1 over expression, using the Dax1 transgenic mouse line, Dax1812 (1), on expression of Sox9, a critical testis-forming gene. Immunostaining of Dax1812 gonads revealed reduced Sox9 expression, suggesting excess Dax1 antagonises Sox9 upregulation during the early stages of sex determination. To determine whether antagonism of Sox9 was occurring at the transcriptional level we assessed the effect of excess Dax1 on the activity of the Testis-Specific Enhancer of Sox9 (TES), which drives Sox9 transcription in the developing XY gonad (3). In combination, the in vivo and in vitro evidence strongly suggests that Dax1, when present in excess, can repress Sox9 expression through TES and that this repression occurs through inhibition of Steroidogenic Factor-1 activity. With this work we have identified a potential mechanism for disruption of the male-specific sex determination pathway caused by DAX1 duplication and leading to DSD in XY individuals.

scholarly journals Polo-like kinase 3 inhibits glucose metabolism in colorectal cancer by targeting HSP90/STAT3/HK2 signaling

2019 ◽  
Vol 38 (1) ◽  
Author(s):  
Baochi Ou ◽  
Hongze Sun ◽  
Jingkun Zhao ◽  
Zhuoqing Xu ◽  
Yuan Liu ◽  
...  
Keyword(s):  
Colorectal Cancer ◽  
Glucose Metabolism ◽  
Transcriptional Activation ◽  
Lactate Production ◽  
Luciferase Reporter ◽  
Transcriptional Level ◽  
Atp Production ◽  
Reporter Assays

Abstract Background Polo-like kinase 3 (PLK3) has been documented as a tumor suppressor in several types of malignancies. However, the role of PLK3 in colorectal cancer (CRC) progression and glucose metabolism remains to be known. Methods The expression of PLK3 in CRC tissues was determined by immunohistochemistry. Cells proliferation was examined by EdU, CCK-8 and in vivo analyses. Glucose metabolism was assessed by detecting lactate production, glucose uptake, mitochondrial respiration, extracellular acidification rate, oxygen consumption rate and ATP production. Chromatin immunoprecipitation, luciferase reporter assays and co-immunoprecipitation were performed to explore the signaling pathway. Specific targeting by miRNAs was determined by luciferase reporter assays and correlation with target protein expression. Results PLK3 was significantly downregulated in CRC tissues and its low expression was correlated with worse prognosis of patients. In vitro and in vivo experiments revealed that PLK3 contributed to growth inhibition of CRC cells. Furthermore, we demonstrated that PLK3 impeded glucose metabolism via targeting Hexokinase 2 (HK2) expression. Mechanically, PLK3 bound to Heat shock protein 90 (HSP90) and facilitated its degradation, which led to a significant decrease of phosphorylated STAT3. The downregulation of p-STAT3 further suppressed the transcriptional activation of HK2. Moreover, our investigations showed that PLK3 was directly targeted by miR-106b at post-transcriptional level in CRC cells. Conclusion This study suggests that PLK3 inhibits glucose metabolism by targeting HSP90/STAT3/HK2 signaling and PLK3 may serve as a potential therapeutic target in colorectal cancer.

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