Transcription factor signal transducer and activator of transcription 6 (STAT6) is an inhibitory factor for adult myogenesis

Abstract Background The signal transducer and activator of transcription 6 (STAT6) transcription factor plays a vitally important role in immune cells, where it is activated mainly by interleukin-4 (IL-4). Because IL-4 is an essential cytokine for myotube formation, STAT6 might also be involved in myogenesis as part of IL-4 signaling. This study was conducted to elucidate the role of STAT6 in adult myogenesis in vitro and in vivo. Methods Myoblasts were isolated from male mice and were differentiated on a culture dish to evaluate the change in STAT6 during myotube formation. Then, the effects of STAT6 overexpression and inhibition on proliferation, differentiation, and fusion in those cells were studied. Additionally, to elucidate the myogenic role of STAT6 in vivo, muscle regeneration after injury was evaluated in STAT6 knockout mice. Results IL-4 can increase STAT6 phosphorylation, but STAT6 phosphorylation decreased during myotube formation in culture. STAT6 overexpression decreased, but STAT6 knockdown increased the differentiation index and the fusion index. Results indicate that STAT6 inhibited myogenin protein expression. Results of in vivo experiments show that STAT6 knockout mice exhibited better regeneration than wild-type mice 5 days after cardiotoxin-induced injury. It is particularly interesting that results obtained using cells from STAT6 knockout mice suggest that this STAT6 inhibitory action for myogenesis was not mediated by IL-4 but might instead be associated with p38 mitogen-activated protein kinase phosphorylation. However, STAT6 was not involved in the proliferation of myogenic cells in vitro and in vivo. Conclusion Results suggest that STAT6 functions as an inhibitor of adult myogenesis. Moreover, results suggest that the IL-4-STAT6 signaling axis is unlikely to be responsible for myotube formation.

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Thymoquinone, a Dietary Bioactive Compound, Exerts Anti-Inflammatory Effects in Colitis by Stimulating Expression of the Colonic Epithelial PPAR-γ Transcription Factor

Nutrients ◽

10.3390/nu13041343 ◽

2021 ◽

Vol 13 (4) ◽

pp. 1343

Author(s):

Balaji Venkataraman ◽

Saeeda Almarzooqi ◽

Vishnu Raj ◽

Abdullah T. Alhassani ◽

Ahmad S. Alhassani ◽

...

Keyword(s):

Transcription Factor ◽

Activity Index ◽

Nigella Sativa ◽

Mapk Signaling ◽

Mitogen Activated Protein Kinase ◽

Ppar Γ ◽

Anti Inflammatory ◽

Ht 29

Inflammatory bowel diseases (IBD) are chronic inflammatory disorders with increasing incidence and prevalence worldwide. Here, we investigated thymoquinone (TQ), a naturally occurring phytochemical present in Nigella sativa, for anti-inflammatory effects in colonic inflammation. To address this, we used in vivo (mice) and in vitro (HT-29 cells) models in this investigation. Our results showed that TQ treatment significantly reduced the disease activity index (DAI), myeloperoxidase (MPO) activity, and protected colon microscopic architecture. In addition, TQ also reduced the expression of proinflammatory cytokines and mediators at both the mRNA and protein levels. Further, TQ decreased phosphorylation of the activated mitogen-activated protein kinase (MAPK) signaling pathway and nuclear factor kappa B (NF-κB) proteins and enhanced colon epithelial PPAR-γ transcription factor expression. TQ significantly decreased proinflammatory chemokines (CXCL-1 and IL-8), and mediator (COX-2) mRNA expression in HT-29 cells treated with TNF-α. TQ also increased HT-29 PPAR-γ mRNA, PPAR-γ protein expression, and PPAR-γ promoter activity. These results indicate that TQ inhibits MAPK and NF-κB signaling pathways and transcriptionally regulates PPAR-γ expression to induce potent anti-inflammatory activity in vivo and in vitro models of colon inflammation.

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Genetic Suppressor Element 1 (GSE1) Promotes the Oncogenic and Recurrent Phenotypes of Castration-Resistant Prostate Cancer by Targeting Tumor-Associated Calcium Signal Transducer 2 (TACSTD2)

Cancers ◽

10.3390/cancers13163959 ◽

2021 ◽

Vol 13 (16) ◽

pp. 3959

Author(s):

Oluwaseun Adebayo Bamodu ◽

Yuan-Hung Wang ◽

Chen-Hsun Ho ◽

Su-Wei Hu ◽

Chia-Da Lin ◽

...

Keyword(s):

Prostate Cancer ◽

Disease Progression ◽

Therapy Resistance ◽

Calcium Signal ◽

Signal Transducer ◽

Castration Resistance ◽

Castration Resistant

Background: prostate cancer (PCa) is a principal cause of cancer-related morbidity and mortality. Castration resistance and metastasis are clinical challenges and continue to impede therapeutic success, despite diagnostic and therapeutic advances. There are reports of the oncogenic activity of genetic suppressor element (GSE)1 in breast and gastric cancers; however, its role in therapy resistance, metastasis, and susceptibility to disease recurrence in PCa patients remains unclear. Objective: this study investigated the role of aberrantly expressed GSE1 in the metastasis, therapy resistance, relapse, and poor prognosis of advanced PCa. Methods: we used a large cohort of multi-omics data and in vitro, ex vivo, and in vivo assays to investigate the potential effect of altered GSE1 expression on advanced/castration-resistant PCa (CRPC) treatment responses, disease progression, and prognosis. Results: using a multi-cohort approach, we showed that GSE1 is upregulated in PCa, while tumor-associated calcium signal transducer 2 (TACSTD2) is downregulated. Moreover, the direct, but inverse, correlation interaction between GSE1 and TACSTD2 drives metastatic disease, castration resistance, and disease progression and modulates the clinical and immune statuses of patients with PCa. Patients with GSE1highTACSTD2low expression are more prone to recurrence and disease-specific death than their GSE1lowTACSTD2high counterparts. Interestingly, we found that the GSE1–TACSTD2 expression profile is associated with the therapy responses and clinical outcomes in patients with PCa, especially those with metastatic/recurrent disease. Furthermore, we demonstrate that the shRNA-mediated targeting of GSE1 (shGSE1) significantly inhibits cell proliferation and attenuates cell migration and tumorsphere formation in metastatic PC3 and DU145 cell lines, with an associated suppression of VIM, SNAI2, and BCL2 and the concomitant upregulation of TACSTD2 and BAX. Moreover, shGSE1 enhances sensitivity to the antiandrogens abiraterone and enzalutamide in vitro and in vivo. Conclusion: these data provide preclinical evidence of the oncogenic role of dysregulated GSE1–TACSTD2 signaling and show that the molecular or pharmacological targeting of GSE1 is a workable therapeutic strategy for inhibiting androgen-driven oncogenic signals, re-sensitizing CRPC to treatment, and repressing the metastatic/recurrent phenotypes of patients with PCa.

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Progression and Differentiation of Alveolar Rhabdomyosarcoma Is Regulated by PAX7 Transcription Factor—Significance of Tumor Subclones

Cells ◽

10.3390/cells10081870 ◽

2021 ◽

Vol 10 (8) ◽

pp. 1870

Author(s):

Klaudia Skrzypek ◽

Grażyna Adamek ◽

Marta Kot ◽

Bogna Badyra ◽

Marcin Majka

Keyword(s):

Transcription Factor ◽

Cell Lines ◽

Migration Activity ◽

Id Proteins ◽

Rh30 Cell ◽

Str Profile ◽

And Migration

Rhabdomyosarcoma (RMS), is the most frequent soft tissue tumor in children that originates from disturbances in differentiation process. Mechanisms leading to the development of RMS are still poorly understood. Therefore, by analysis of two RMS RH30 cell line subclones, one subclone PAX7 negative, while the second one PAX7 positive, and comparison with other RMS cell lines we aimed at identifying new mechanisms crucial for RMS progression. RH30 subclones were characterized by the same STR profile, but different morphology, rate of proliferation, migration activity and chemotactic abilities in vitro, as well as differences in tumor morphology and growth in vivo. Our analysis indicated a different level of expression of adhesion molecules (e.g., from VLA and ICAM families), myogenic microRNAs, such as miR-206 and transcription factors, such as MYOD, MYOG, SIX1, and ID. Silencing of PAX7 transcription factor with siRNA confirmed the crucial role of PAX7 transcription factor in proliferation, differentiation and migration of RMS cells. To conclude, our results suggest that tumor cell lines with the same STR profile can produce subclones that differ in many features and indicate crucial roles of PAX7 and ID proteins in the development of RMS.

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Role for the Ran Binding Protein, Mog1p, in Saccharomyces cerevisiae SLN1-SKN7 Signal Transduction

Eukaryotic Cell ◽

10.1128/ec.3.6.1544-1556.2004 ◽

2004 ◽

Vol 3 (6) ◽

pp. 1544-1556 ◽

Cited By ~ 17

Author(s):

Jade Mei-Yeh Lu ◽

Robert J. Deschenes ◽

Jan S. Fassler

Keyword(s):

Signal Transduction ◽

Transcription Factor ◽

Osmotic Stress ◽

Kinase Activity ◽

Mitogen Activated Protein Kinase ◽

Osmotic Response ◽

Mitogen Activated Protein ◽

Kinase Pathway

ABSTRACT Yeast Sln1p is an osmotic stress sensor with histidine kinase activity. Modulation of Sln1 kinase activity in response to changes in the osmotic environment regulates the activity of the osmotic response mitogen-activated protein kinase pathway and the activity of the Skn7p transcription factor, both important for adaptation to changing osmotic stress conditions. Many aspects of Sln1 function, such as how kinase activity is regulated to allow a rapid response to the continually changing osmotic environment, are not understood. To gain insight into Sln1p function, we conducted a two-hybrid screen to identify interactors. Mog1p, a protein that interacts with the yeast Ran1 homolog, Gsp1p, was identified in this screen. The interaction with Mog1p was characterized in vitro, and its importance was assessed in vivo. mog1 mutants exhibit defects in SLN1-SKN7 signal transduction and mislocalization of the Skn7p transcription factor. The requirement for Mog1p in normal localization of Skn7p to the nucleus does not fully account for the mog1-related defects in SLN1-SKN7 signal transduction, raising the possibility that Mog1p may play a role in Skn7 binding and activation of osmotic response genes.

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The use of siRNA as a pharmacological tool to assess a role for the transcription factor NF-IL6 in the brain under in vitro and in vivo conditions during LPS-induced inflammatory stimulation

Journal of Basic and Clinical Physiology and Pharmacology ◽

10.1515/jbcpp-2017-0017 ◽

2017 ◽

Vol 28 (6) ◽

Cited By ~ 2

Author(s):

Jelena Damm ◽

Joachim Roth ◽

Rüdiger Gerstberger ◽

Christoph Rummel

Keyword(s):

Transcription Factor ◽

Brain Cells ◽

Nuclear Factor ◽

Si Rna ◽

The Brain ◽

Deficient Mice ◽

Transcription Factor Nuclear Factor

AbstractBackground:Studies with NF-IL6-deficient mice indicate that this transcription factor plays a dual role during systemic inflammation with pro- and anti-inflammatory capacities. Here, we aimed to characterize the role of NF-IL6 specifically within the brain.Methods:In this study, we tested the capacity of short interfering (si) RNA to silence the inflammatory transcription factor nuclear factor-interleukin 6 (NF-IL6) in brain cells underResults:In cells of a mixed neuronal and glial primary culture from the ratConclusions:This approach was, thus, not suitable to characterize the role NF-IL6 in the brain

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Lineage-specific requirements of β-catenin in neural crest development

The Journal of Cell Biology ◽

10.1083/jcb.200209039 ◽

2002 ◽

Vol 159 (5) ◽

pp. 867-880 ◽

Cited By ~ 207

Author(s):

Lisette Hari ◽

Véronique Brault ◽

Maurice Kléber ◽

Hye-Youn Lee ◽

Fabian Ille ◽

...

Keyword(s):

Transcription Factor ◽

Neural Crest ◽

Neural Crest Cells ◽

Neural Crest Stem Cells ◽

Downstream Signaling ◽

Neural Crest Development ◽

Sensory Neurogenesis

β-Catenin plays a pivotal role in cadherin-mediated cell adhesion. Moreover, it is a downstream signaling component of Wnt that controls multiple developmental processes such as cell proliferation, apoptosis, and fate decisions. To study the role of β-catenin in neural crest development, we used the Cre/loxP system to ablate β-catenin specifically in neural crest stem cells. Although several neural crest–derived structures develop normally, mutant animals lack melanocytes and dorsal root ganglia (DRG). In vivo and in vitro analyses revealed that mutant neural crest cells emigrate but fail to generate an early wave of sensory neurogenesis that is normally marked by the transcription factor neurogenin (ngn) 2. This indicates a role of β-catenin in premigratory or early migratory neural crest and points to heterogeneity of neural crest cells at the earliest stages of crest development. In addition, migratory neural crest cells lateral to the neural tube do not aggregate to form DRG and are unable to produce a later wave of sensory neurogenesis usually marked by the transcription factor ngn1. We propose that the requirement of β-catenin for the specification of melanocytes and sensory neuronal lineages reflects roles of β-catenin both in Wnt signaling and in mediating cell–cell interactions.

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MAPK-directed activation of the whitefly transcription factor CREB leads to P450-mediated imidacloprid resistance

Proceedings of the National Academy of Sciences ◽

10.1073/pnas.1913603117 ◽

2020 ◽

Vol 117 (19) ◽

pp. 10246-10253 ◽

Cited By ~ 7

Author(s):

Xin Yang ◽

Shun Deng ◽

Xuegao Wei ◽

Jing Yang ◽

Qiannan Zhao ◽

...

Keyword(s):

Transcription Factor ◽

Signaling Pathway ◽

Gene Families ◽

Mapk Signaling ◽

Mitogen Activated Protein Kinase ◽

Bzip Transcription Factor ◽

Camp Response Element ◽

Response Element

The evolution of insect resistance to pesticides poses a continuing threat to agriculture and human health. While much is known about the proximate molecular and biochemical mechanisms that confer resistance, far less is known about the regulation of the specific genes/gene families involved, particularly by trans-acting factors such as signal-regulated transcription factors. Here we resolve in fine detail the trans-regulation of CYP6CM1, a cytochrome P450 that confers resistance to neonicotinoid insecticides in the whitefly Bemisia tabaci, by the mitogen-activated protein kinase (MAPK)-directed activation of the transcription factor cAMP-response element binding protein (CREB). Reporter gene assays were used to identify the putative promoter of CYP6CM1, but no consistent polymorphisms were observed in the promoter of a resistant strain of B. tabaci (imidacloprid-resistant, IMR), which overexpresses this gene, compared to a susceptible strain (imidacloprid-susceptible, IMS). Investigation of potential trans-acting factors using in vitro and in vivo assays demonstrated that the bZIP transcription factor CREB directly regulates CYP6CM1 expression by binding to a cAMP-response element (CRE)-like site in the promoter of this gene. CREB is overexpressed in the IMR strain, and inhibitor, luciferase, and RNA interference assays revealed that a signaling pathway of MAPKs mediates the activation of CREB, and thus the increased expression of CYP6CM1, by phosphorylation-mediated signal transduction. Collectively, these results provide mechanistic insights into the regulation of xenobiotic responses in insects and implicate both the MAPK-signaling pathway and a transcription factor in the development of pesticide resistance.

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Interleukin 1 induces renal CD44 expression in vivo and in vitro: role of the transcription factor Egr-1

Nephrology ◽

10.1046/j.1440-1797.2002.00046.x ◽

2002 ◽

Vol 7 (3) ◽

pp. 136-144

Author(s):

Kazunori Takazoe ◽

Rita Foti ◽

Lynette A Hurst ◽

Hui Y Lan ◽

Robert C Atkins ◽

...

Keyword(s):

Transcription Factor ◽

Interleukin 1 ◽

Cd44 Expression

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Transcription factor Krüppel-like factor 2 plays a vital role in endothelial colony forming cells differentiation

Cardiovascular Research ◽

10.1093/cvr/cvt113 ◽

2013 ◽

Vol 99 (3) ◽

pp. 514-524 ◽

Cited By ~ 20

Author(s):

Yimeng Song ◽

Xiaoxia Li ◽

Dawei Wang ◽

Chenglai Fu ◽

Zhenjiu Zhu ◽

...

Keyword(s):

Transcription Factor ◽

Tube Formation ◽

Vital Role ◽

Ampk Activation ◽

Cell Markers ◽

Endothelial Colony Forming Cells ◽

Angiogenesis Assay

Abstract Aims Endothelial colony forming cells (ECFCs) participate in post-natal vasculogenesis. We previously reported that vascular endothelial growth factor (VEGF) promotes human ECFC differentiation through AMP-activated protein kinase (AMPK) activation. However, the mechanisms underlying transcriptional regulation of ECFC differentiation still remain largely elusive. Here, we investigated the role of transcription factor Krüppel-like factor 2 (KLF2) in the regulation of ECFC function. Methods and results Human ECFCs were isolated from cord blood and cultured. Treatment with VEGF significantly increased endothelial markers in ECFCs and their capacity for migration and tube formation. The mRNA and protein levels of KLF2 were also significantly up-regulated. This up-regulation was abrogated by AMPK inhibition or by knockdown of KLF2 with siRNA. Furthermore, adenovirus-mediated overexpression of KLF2 promoted ECFC differentiation by enhancing expression of endothelial cell markers, reducing expression of progenitor cell markers, and increasing the capacity for tube formation in vitro, indicating the important role of KLF2 in ECFC-mediated angiogenesis. Histone deacetylase 5 (HDAC5) was phosphorylated by AMPK activity induced by VEGF and the AMPK agonist AICAR (5-amino-1-β-d-ribofuranosyl-imidazole-4-carboxamide). In vivo angiogenesis assay revealed that overexpression of KLF2 in bone-marrow-derived pro-angiogenic progenitor cells promoted vessel formation when the cells were implanted in C57BL/6 mice. Conclusion Up-regulation of KLF2 by AMPK activation constitutes a novel mechanism of ECFC differentiation, and may have therapeutic value in the treatment of ischaemic heart disease.

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Limited role of CD28-mediated signals in T helper subset differentiation.

Journal of Experimental Medicine ◽

10.1084/jem.184.3.803 ◽

1996 ◽

Vol 184 (3) ◽

pp. 803-810 ◽

Cited By ~ 75

Author(s):

D R Brown ◽

J M Green ◽

N H Moskowitz ◽

M Davis ◽

C B Thompson ◽

...

Keyword(s):

T Cell Differentiation ◽

Interleukin 4 ◽

T Helper ◽

T Helper 1 ◽

Absolute Requirement ◽

Costimulatory Signals ◽

Draining Lymph Nodes

The role of CD28-mediated signals in T helper cell maturation is not fully understood. We tested the requirement for costimulation through CD28 in several systems of CD4+, T cell differentiation. In vivo priming of mice with genetic disruption of CD28 (CD28-/-) yielded normal levels of antigen-specific interferon gamma production but markedly diminished levels of interleukin 4 (IL-4) after in vitro restimulation. In response to the pathogenic microbe, Leishman a major, C57BL6 CD28-/- mice were fully capable of controlling infection and exhibited a normal T helper 1 response. BALB/c CD28-/- mice unexpectedly exhibited normal susceptibility to L. major. BALB/c CD28-/- mice developed high levels of IL-4 mRNA and protein induction in the draining lymph nodes. In addition, susceptibility of BALB/c CD28-/- mice was reversed by neutralization of IL-4 in vivo. We also activated transgenic CD28-bearing T cells from the BALB and C57BL background in vitro in the presence of CTLA4Ig. BALB cells had greater IL-4 producing capacity than C57BL cells in the absence of costimulation. Diverse factors including costimulatory signals, genetic polymorphism, and the nature of the immunogen all influence T helper phenotype commitment, but these results provide evidence that CD28 is not an absolute requirement for generating either Th1 or Th2 responses.

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