scholarly journals Chromatin-release of the long ncRNA A-ROD is required for transcriptional activation of its target gene DKK1

2017 ◽  
Author(s):  
Evgenia Ntini ◽  
Julia Liz ◽  
Jose M Muino ◽  
Annalisa Marsico ◽  
Ulf Andersson Ørom
Keyword(s):  
Transcriptional Activation ◽  
Target Gene ◽  
Regulation Of Transcription ◽  
Dependent Manner ◽  
Regulatory Interaction ◽  
Activating Function ◽  
Chromatin Interactions ◽  
Functional Involvement ◽  
Non Coding Rnas ◽  
Mcf 7

AbstractLong non-coding RNAs (ncRNAs) are involved in both positive and negative regulation of transcription. Long ncRNAs are often enriched in the nucleus and at chromatin but whether chromatin-release plays a functional role is unknown. Here, we used epigenetic marks, expression level and strength of chromatin interactions to group long ncRNAs and find that those engaged in strong chromatin interactions are less enriched at chromatin in MCF-7 cells, suggesting a functional involvement of chromatin-release of long ncRNAs in transcriptional regulation. To study this further, we identify the long ncRNA A-ROD, an activating regulator of the Wnt signaling inhibitor DKK1. We show that A-ROD enhances transcription elongation of DKK1 in an RNA-dependent manner and that A-ROD recruits EBP1 to the DKK1 promoter. Our data suggest that the activating function depends on the release of A-ROD from chromatin, and further identify a functional regulatory interaction mediated by A-ROD in the transcription activation of DKK1. We propose that the release of a subset of long ncRNAs is important for their function, adding a new mechanistic perspective to the subcellular localization of long ncRNAs.

Progesterone enhances target gene transcription by receptor free of heat shock proteins hsp90, hsp56, and hsp70

1991 ◽  
Vol 11 (10) ◽  
pp. 4998-5004
Author(s):  
M K Bagchi ◽  
S Y Tsai ◽  
M J Tsai ◽  
B W O'Malley
Keyword(s):  
Heat Shock ◽  
Heat Shock Proteins ◽  
Heat Shock Protein ◽  
Transcriptional Activation ◽  
Target Gene ◽  
Steroid Hormone ◽  
Receptor Activation ◽  
Target Cells ◽  
Dependent Manner ◽  
Shock Proteins

Steroid receptors regulate transcription of target genes in vivo and in vitro in a steroid hormone-dependent manner. Unoccupied progesterone receptor exists in the low-salt homogenates of target cells as a functionally inactive 8 to 10S complex with several nonreceptor components such as two molecules of 90-kDa heat shock protein (hsp90), a 70-kDa heat shock protein (hsp70), and a 56-kDa heat shock protein (hsp56). Ligand-induced dissociation of receptor-associated proteins such as hsp90 has been proposed as the mechanism of receptor activation. Nevertheless, it has not been established whether, beyond release of heat shock proteins, the steroidal ligand plays a role in modulating receptor activity. To examine whether the release of these nonreceptor proteins from receptor complex results in a constitutively active receptor, we isolated an unliganded receptor form essentially free of hsp90, hsp70, and hsp56. Using a recently developed steroid hormone-responsive cell-free transcription system, we demonstrate for the first time that the dissociation of heat shock proteins is not sufficient to generate a functionally active receptor. This purified receptor still requires hormone for high-affinity binding to a progesterone response element and for efficient transcriptional activation of a target gene. When an antiprogestin, Ru486, is bound to the receptor, it fails to promote efficient transcription. We propose that in the cell, in addition to the release of receptor-associated inhibitory proteins, a distinct hormone-mediated activation event must precede efficient gene activation.

scholarly journals Progesterone enhances target gene transcription by receptor free of heat shock proteins hsp90, hsp56, and hsp70.

1991 ◽  
Vol 11 (10) ◽  
pp. 4998-5004 ◽  
Author(s):  
M K Bagchi ◽  
S Y Tsai ◽  
M J Tsai ◽  
B W O'Malley
Keyword(s):  
Heat Shock ◽  
Heat Shock Proteins ◽  
Heat Shock Protein ◽  
Transcriptional Activation ◽  
Target Gene ◽  
Steroid Hormone ◽  
Receptor Activation ◽  
Target Cells ◽  
Dependent Manner ◽  
Shock Proteins

Steroid receptors regulate transcription of target genes in vivo and in vitro in a steroid hormone-dependent manner. Unoccupied progesterone receptor exists in the low-salt homogenates of target cells as a functionally inactive 8 to 10S complex with several nonreceptor components such as two molecules of 90-kDa heat shock protein (hsp90), a 70-kDa heat shock protein (hsp70), and a 56-kDa heat shock protein (hsp56). Ligand-induced dissociation of receptor-associated proteins such as hsp90 has been proposed as the mechanism of receptor activation. Nevertheless, it has not been established whether, beyond release of heat shock proteins, the steroidal ligand plays a role in modulating receptor activity. To examine whether the release of these nonreceptor proteins from receptor complex results in a constitutively active receptor, we isolated an unliganded receptor form essentially free of hsp90, hsp70, and hsp56. Using a recently developed steroid hormone-responsive cell-free transcription system, we demonstrate for the first time that the dissociation of heat shock proteins is not sufficient to generate a functionally active receptor. This purified receptor still requires hormone for high-affinity binding to a progesterone response element and for efficient transcriptional activation of a target gene. When an antiprogestin, Ru486, is bound to the receptor, it fails to promote efficient transcription. We propose that in the cell, in addition to the release of receptor-associated inhibitory proteins, a distinct hormone-mediated activation event must precede efficient gene activation.

scholarly journals Cyclin-Dependent Kinase 8 Positively Cooperates with Mediator To Promote Thyroid Hormone Receptor-Dependent Transcriptional Activation

2010 ◽  
Vol 30 (10) ◽  
pp. 2437-2448 ◽  
Author(s):  
Madesh Belakavadi ◽  
Joseph D. Fondell
Keyword(s):  
Thyroid Hormone ◽  
Transcriptional Activation ◽  
Target Gene ◽  
Thyroid Hormone Receptor ◽  
Type I ◽  
Dependent Manner ◽  
Gene Promoters ◽  
Cyclin Dependent Kinase ◽  
Pol Ii

ABSTRACT Mediator is a multisubunit assemblage of proteins originally identified in humans as a coactivator bound to thyroid hormone receptors (TRs) and essential for thyroid hormone (T3)-dependent transcription. Cyclin-dependent kinase 8 (CDK8), cyclin C, MED12, and MED13 form a variably associated Mediator subcomplex (termed the CDK8 module) whose functional role in TR-dependent transcription remains unclear. Using in vitro and cellular approaches, we show here that Mediator complexes containing the CDK8 module are specifically recruited into preinitiation complexes at the TR target gene type I deiodinase (DioI) together with RNA polymerase II (Pol II) in a TR- and T3-dependent manner. We found that CDK8 is essential for robust T3-dependent Dio1 transcription and that CDK8 knockdown via RNA interference decreased Pol II occupancy, and also the recruitment of the Pol II kinase CDK9, at the DioI promoter. Chromatin immunoprecipitation revealed CDK8 occupancy at the DioI promoter concurrent with active transcription, thus suggesting CDK8 involvement in transcriptional reinitiation. Mutagenesis assays showed that CDK8 kinase activity is necessary for full T3-dependent DioI activation, whereas in vitro kinase studies indicated that CDK8 may contribute to Pol II phosphorylation. Collectively, our data suggest CDK8 plays an important coactivator role in TR-dependent transcription by promoting Pol II recruitment and activation at TR target gene promoters.

scholarly journals Increased processing of SINE B2 ncRNAs unveils a novel type of transcriptome deregulation in amyloid beta neuropathology

eLife ◽  
2020 ◽  
Vol 9 ◽  
Author(s):  
Yubo Cheng ◽  
Luke Saville ◽  
Babita Gollen ◽  
Christopher Isaac ◽  
Abel Belay ◽  
...  
Keyword(s):  
Amyloid Beta ◽  
Transcriptional Activation ◽  
Rna Processing ◽  
Target Gene ◽  
Amyloid Toxicity ◽  
B2 Rna ◽  
Mouse Hippocampus ◽  
Response To Stress ◽  
Non Coding Rnas ◽  
Pathologic Processes

The functional importance of many non-coding RNAs (ncRNAs) generated by repetitive elements and their connection with pathologic processes remains elusive. B2 RNAs, a class of ncRNAs of the B2 family of SINE repeats, mediate through their processing the transcriptional activation of various genes in response to stress. Here, we show that this response is dysfunctional during amyloid beta toxicity and pathology in the mouse hippocampus due to increased levels of B2 RNA processing, leading to constitutively elevated B2 RNA target gene expression and high Trp53 levels. Evidence indicates that Hsf1, a master regulator of stress response, mediates B2 RNA processing in hippocampal cells and is activated during amyloid toxicity, accelerating the processing of SINE RNAs and gene hyper-activation. Our study reveals that in mouse, SINE RNAs constitute a novel pathway deregulated in amyloid beta pathology, with potential implications for similar cases in the human brain, such as Alzheimer’s disease (AD).

Design, Synthesis and Cytotoxicity Evaluation of New 3, 5-Disubstituted-2-Thioxoimidazolidinones

2018 ◽  
Vol 18 (4) ◽  
pp. 573-582 ◽  
Author(s):  
Khaled R.A. Abdellatif ◽  
Mostafa M. Elbadawi ◽  
Mohammed T. Elsaady ◽  
Amer A. Abd El-Hafeez ◽  
Takashi Fujimura ◽  
...  
Keyword(s):  
Breast Cancer ◽  
Cell Line ◽  
Cell Lines ◽  
Cancer Cell ◽  
Topoisomerase I ◽  
Cancer Cell Line ◽  
Cytotoxic Agents ◽  
Dependent Manner ◽  
Human Lung Fibroblast ◽  
Mcf 7

Background: Some 2-thioxoimidazolidinones have been reported as anti-prostate and anti-breast cancer agents through their inhibitory activity on topoisomerase I that is considered as a potential chemotherapeutic target. Objective: A new series of 3,5-disubstituted-2-thioxoimidazolidinone derivatives 10a-f and their S-methyl analogs 11a-f were designed, synthesized and evaluated for cytotoxicity against human prostate cancer cell line (PC-3), human breast cancer cell line (MCF-7) and non-cancerous human lung fibroblast cell line (WI-38). </P><P> Results and Method: While compounds 10a-f showed a broad range of activities against PC-3 and MCF-7 cell lines (IC50 = 34.0 – 186.9 and 24.6 – 147.5 µM respectively), the S-methyl analogs 11a-f showed (IC50 = 22.7 – 198.5 and 16.9 – 188.2 µM respectively) in comparison with 5-fluorouracil (IC50 = 60.7 and 40.7 µM respectively). 11c (IC50 = 22.7 and 29.2 µM) and 11f (IC50 = 28.7 and 16.9 µM) were the most potent among all compounds against both PC-3 and MCF-7 respectively with no cytotoxicity against WI-38. Conclusion: The newly synthesized compounds showed good activity against PC-3 and MCF-7 cell lines in comparison with 5-fluorouracil. Compounds 11c and 11f bound with human topoisomerase I similar to its known inhibitors and significantly inhibited its DNA relaxation activity in a dose dependent manner which may rationalize their molecular mechanism as cytotoxic agents.

scholarly journals SUMO-Activating Enzyme Subunit 1 (SAE1) Is a Promising Diagnostic Cancer Metabolism Biomarker of Hepatocellular Carcinoma

Cells ◽  
2021 ◽  
Vol 10 (1) ◽  
pp. 178
Author(s):  
Jiann Ruey Ong ◽  
Oluwaseun Adebayo Bamodu ◽  
Nguyen Viet Khang ◽  
Yen-Kuang Lin ◽  
Chi-Tai Yeh ◽  
...  
Keyword(s):  
Hepatocellular Carcinoma ◽  
Cancer Metabolism ◽  
Interaction Analysis ◽  
Normal Liver ◽  
Diagnostic Value ◽  
Vital Role ◽  
Regulation Of Transcription ◽  
Dependent Manner ◽  
Post Translational Modification ◽  
Characteristic Analysis

Hepatocellular carcinoma (HCC) is one of the most diagnosed malignancies and a leading cause of cancer-related mortality globally. This is exacerbated by its highly aggressive phenotype, and limitation in early diagnosis and effective therapies. The SUMO-activating enzyme subunit 1 (SAE1) is a component of a heterodimeric small ubiquitin-related modifier that plays a vital role in SUMOylation, a post-translational modification involving in cellular events such as regulation of transcription, cell cycle and apoptosis. Reported overexpression of SAE1 in glioma in a stage-dependent manner suggests it has a probable role in cancer initiation and progression. In this study, hypothesizing that SAE1 is implicated in HCC metastatic phenotype and poor prognosis, we analyzed the expression of SAE1 in several cancer databases and to unravel the underlying molecular mechanism of SAE1-associated hepatocarcinogenesis. Here, we demonstrated that SAE1 is over-expressed in HCC samples compared to normal liver tissue, and this observed SAE1 overexpression is stage and grade-dependent and associated with poor survival. The receiver operating characteristic analysis of SAE1 in TCGA−LIHC patients (n = 421) showed an AUC of 0.925, indicating an excellent diagnostic value of SAE1 in HCC. Our protein-protein interaction analysis for SAE1 showed that SAE1 interacted with and activated oncogenes such as PLK1, CCNB1, CDK4 and CDK1, while simultaneously inhibiting tumor suppressors including PDK4, KLF9, FOXO1 and ALDH2. Immunohistochemical staining and clinicopathological correlate analysis of SAE1 in our TMU-SHH HCC cohort (n = 54) further validated the overexpression of SAE1 in cancerous liver tissues compared with ‘normal’ paracancerous tissue, and high SAE1 expression was strongly correlated with metastasis and disease progression. The oncogenic effect of upregulated SAE1 is associated with dysregulated cancer metabolic signaling. In conclusion, the present study demonstrates that SAE1 is a targetable cancer metabolic biomarker with high potential diagnostic and prognostic implications for patients with HCC.

scholarly journals Anticancer Potential of Biogenic Silver Nanoparticles: A Mechanistic Study

Pharmaceutics ◽  
2021 ◽  
Vol 13 (5) ◽  
pp. 707
Author(s):  
Mohd Shahnawaz Khan ◽  
Alya Alomari ◽  
Shams Tabrez ◽  
Iftekhar Hassan ◽  
Rizwan Wahab ◽  
...  
Keyword(s):  
Silver Nanoparticles ◽  
Cancer Cells ◽  
Cell Lines ◽  
Human Life ◽  
Mechanistic Study ◽  
Dependent Manner ◽  
Rt Pcr ◽  
Cell Viability Assay ◽  
Hct 116 ◽  
Mcf 7

The continuous loss of human life due to the paucity of effective drugs against different forms of cancer demands a better/noble therapeutic approach. One possible way could be the use of nanostructures-based treatment methods. In the current piece of work, we have synthesized silver nanoparticles (AgNPs) using plant (Heliotropiumbacciferum) extract using AgNO3 as starting materials. The size, shape, and structure of synthesized AgNPs were confirmed by various spectroscopy and microscopic techniques. The average size of biosynthesized AgNPs was found to be in the range of 15 nm. The anticancer potential of these AgNPs was evaluated by a battery of tests such as MTT, scratch, and comet assays in breast (MCF-7) and colorectal (HCT-116) cancer models. The toxicity of AgNPs towards cancer cells was confirmed by the expression pattern of apoptotic (p53, Bax, caspase-3) and antiapoptotic (BCl-2) genes by RT-PCR. The cell viability assay showed an IC50 value of 5.44 and 9.54 µg/mL for AgNPs in MCF-7 and HCT-116 cell lines respectively. We also observed cell migration inhibiting potential of AgNPs in a concentration-dependent manner in MCF-7 cell lines. A tremendous rise (150–250%) in the production of ROS was observed as a result of AgNPs treatment compared with control. Moreover, the RT-PCR results indicated the difference in expression levels of pro/antiapoptotic proteins in both cancer cells. All these results indicate that cell death observed by us is mediated by ROS production, which might have altered the cellular redox status. Collectively, we report the antimetastasis potential of biogenic synthesized AgNPs against breast and colorectal cancers. The biogenic synthesis of AgNPs seems to be a promising anticancer therapy with greater efficacy against the studied cell lines.

scholarly journals Identification and Roles of miR-29b-1-3p and miR29a-3p-Regulated and Non-Regulated lncRNAs in Endocrine-Sensitive and Resistant Breast Cancer Cells

Cancers ◽  
2021 ◽  
Vol 13 (14) ◽  
pp. 3530
Author(s):  
Penn Muluhngwi ◽  
Carolyn M. Klinge
Keyword(s):  
Breast Cancer ◽  
Cancer Survival ◽  
Expression Patterns ◽  
Endocrine Resistance ◽  
Estrogen Receptor Α ◽  
Resistant Cell ◽  
Differentially Expressed ◽  
Primary Tumors ◽  
Non Coding Rnas ◽  
Mcf 7

Despite improvements in the treatment of endocrine-resistant metastatic disease using combination therapies in patients with estrogen receptor α (ERα) primary tumors, the mechanisms underlying endocrine resistance remain to be elucidated. Non-coding RNAs (ncRNAs), including microRNAs (miRNA) and long non-coding RNAs (lncRNA), are targets and regulators of cell signaling pathways and their exosomal transport may contribute to metastasis. Previous studies have shown that a low expression of miR-29a-3p and miR-29b-3p is associated with lower overall breast cancer survival before 150 mos. Transient, modest overexpression of miR-29b1-3p or miR-29a-3p inhibited MCF-7 tamoxifen-sensitive and LCC9 tamoxifen-resistant cell proliferation. Here, we identify miR-29b-1/a-regulated and non-regulated differentially expressed lncRNAs in MCF-7 and LCC9 cells using next-generation RNA seq. More lncRNAs were miR-29b-1/a-regulated in LCC9 cells than in MCF-7 cells, including DANCR, GAS5, DSCAM-AS1, SNHG5, and CRND. We examined the roles of miR-29-regulated and differentially expressed lncRNAs in endocrine-resistant breast cancer, including putative and proven targets and expression patterns in survival analysis using the KM Plotter and TCGA databases. This study provides new insights into lncRNAs in endocrine-resistant breast cancer.

scholarly journals Wnt/β-catenin Pathway-Mediated PPARδ Expression during Embryonic Development Differentiation and Disease

2021 ◽  
Vol 22 (4) ◽  
pp. 1854
Author(s):  
Tabinda Sidrat ◽  
Zia-Ur Rehman ◽  
Myeong-Don Joo ◽  
Kyeong-Lim Lee ◽  
Il-Keun Kong
Keyword(s):  
Embryonic Development ◽  
Transcriptional Activation ◽  
Target Gene ◽  
Developmental Stages ◽  
Embryonic Stem ◽  
Hereditary Diseases ◽  
Peroxisome Proliferator ◽  
Peroxisome Proliferator Activated Receptor ◽  
Stem Cell Regulation ◽  
Early Developmental

The Wnt/β-catenin signaling pathway plays a crucial role in early embryonic development. Wnt/β-catenin signaling is a major regulator of cell proliferation and keeps embryonic stem cells (ESCs) in the pluripotent state. Dysregulation of Wnt signaling in the early developmental stages causes several hereditary diseases that lead to embryonic abnormalities. Several other signaling molecules are directly or indirectly activated in response to Wnt/β-catenin stimulation. The crosstalk of these signaling factors either synergizes or opposes the transcriptional activation of β-catenin/Tcf4-mediated target gene expression. Recently, the crosstalk between the peroxisome proliferator-activated receptor delta (PPARδ), which belongs to the steroid superfamily, and Wnt/β-catenin signaling has been reported to take place during several aspects of embryonic development. However, numerous questions need to be answered regarding the function and regulation of PPARδ in coordination with the Wnt/β-catenin pathway. Here, we have summarized the functional activation of the PPARδ in co-ordination with the Wnt/β-catenin pathway during the regulation of several aspects of embryonic development, stem cell regulation and maintenance, as well as during the progression of several metabolic disorders.

scholarly journals Transcriptome analysis reveals potential function of long non-coding RNAs in 20-hydroxyecdysone regulated autophagy in Bombyx mori

BMC Genomics ◽  
2021 ◽  
Vol 22 (1) ◽  
Author(s):  
Huili Qiao ◽  
Jingya Wang ◽  
Yuanzhuo Wang ◽  
Juanjuan Yang ◽  
Bofan Wei ◽  
...  
Keyword(s):  
Bombyx Mori ◽  
Target Gene ◽  
Fat Body ◽  
Expression Profiles ◽  
Functional Characterization ◽  
Differentially Expressed ◽  
Post Injection ◽  
Biological Processes ◽  
Potential Target ◽  
Non Coding Rnas

Abstract Background 20-hydroxyecdysone (20E) plays important roles in insect molting and metamorphosis. 20E-induced autophagy has been detected during the larval–pupal transition in different insects. In Bombyx mori, autophagy is induced by 20E in the larval fat body. Long non-coding RNAs (lncRNAs) function in various biological processes in many organisms, including insects. Many lncRNAs have been reported to be potential for autophagy occurrence in mammals, but it has not been investigated in insects. Results RNA libraries from the fat body of B. mori dissected at 2 and 6 h post-injection with 20E were constructed and sequenced, and comprehensive analysis of lncRNAs and mRNAs was performed. A total of 1035 lncRNAs were identified, including 905 lincRNAs and 130 antisense lncRNAs. Compared with mRNAs, lncRNAs had longer transcript length and fewer exons. 132 lncRNAs were found differentially expressed at 2 h post injection, compared with 64 lncRNAs at 6 h post injection. Thirty differentially expressed lncRNAs were common at 2 and 6 h post-injection, and were hypothesized to be associated with the 20E response. Target gene analysis predicted 6493 lncRNA-mRNA cis pairs and 42,797 lncRNA-mRNA trans pairs. The expression profiles of LNC_000560 were highly consistent with its potential target genes, Atg4B, and RNAi of LNC_000560 significantly decreased the expression of LNC_000560 and Atg4B. These results indicated that LNC_000560 was potentially involved in the 20E-induced autophagy of the fat body by regulating Atg4B. Conclusions This study provides the genome-wide identification and functional characterization of lncRNAs associated with 20E-induced autophagy in the fat body of B. mori. LNC_000560 and its potential target gene were identified to be related to 20-regulated autophagy in B. mori. These results will be helpful for further studying the regulatory mechanisms of lncRNAs in autophagy and other biological processes in this insect model.

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