Cardiospecific deletion of β-catenin gene associated with an activity violation of signaling cascades involved in the development of myocardial hypertrophy

The aim of our study was to investigate the molecular mechanisms of hypertrophy response under cardiospecific β-catenin haploinsufficiency condition. Materials and methods. Studies were done with β-catenin condtional knockout mice (β-catflox/flox) and α-MHC-Cre-transgenic mice. To induce hypertrophy we used swimming test during 6 weeks. Using western-blot, we have analyzed the level of studied proteins. Results. It has been shown that the β-catenin haploinsufficiency is associated with increased signaling activity of MAPK, PI3-kinase-mTOR-dependent signaling cascades in both: with prolonged physical activity and without it. However, even with an increased activity of this signalling, β-catenin haploinsufficient mice expressed weaker hypertrophic response. Conclusions. The transcriptional activity of β-catenin is necessary for the proper interaction of signaling cascades during heart maturation and adaptation to stress. Keywords: β-catenin, hypertrophy, Wnt-signalling, MAPK signalling, PI3-kinase-mTOR-dependent cascade, PKA-signalling, myocardium.

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Calcium State-Dependent Regulation of Epithelial Cell Quiescence by Stanniocalcin 1a

Frontiers in Cell and Developmental Biology ◽

10.3389/fcell.2021.662915 ◽

2021 ◽

Vol 9 ◽

Author(s):

Shuang Li ◽

Chengdong Liu ◽

Allison Goldstein ◽

Yi Xin ◽

Caihuan Ke ◽

...

Keyword(s):

Molecular Mechanisms ◽

Premature Death ◽

Pi3 Kinase ◽

Dependent Manner ◽

Tor Signaling ◽

State Dependent ◽

Cell Quiescence ◽

Genetic Deletion ◽

Igf1 Receptor ◽

Signaling Activity

The molecular mechanisms regulating cell quiescence-proliferation balance are not well defined. Using a zebrafish model, we report that Stc1a, a secreted glycoprotein, plays a key role in regulating the quiescence-proliferation balance of Ca2+ transporting epithelial cells (ionocytes). Zebrafish stc1a, but not the other stc genes, is expressed in a Ca2+ state-dependent manner. Genetic deletion of stc1a, but not stc2b, increased ionocyte proliferation, leading to elevated body Ca2+ levels, cardiac edema, body swelling, and premature death. The increased ionocyte proliferation was accompanied by an increase in the IGF1 receptor-mediated PI3 kinase-Akt-Tor signaling activity in ionocytes. Inhibition of the IGF1 receptor, PI3 kinase, Akt, and Tor signaling reduced ionocyte proliferation and rescued the edema and premature death in stc1a–/– fish, suggesting that Stc1a promotes ionocyte quiescence by suppressing local IGF signaling activity. Mechanistically, Stc1 acts by inhibiting Papp-aa, a zinc metalloproteinase degrading Igfbp5a. Inhibition of Papp-aa proteinase activity restored ionocyte quiescence-proliferation balance. Genetic deletion of papp-aa or its substrate igfbp5a in the stc1a–/– background reduced ionocyte proliferation and rescued the edema and premature death. These findings uncover a novel and Ca2+ state-dependent pathway regulating cell quiescence. Our findings also provide new insights into the importance of ionocyte quiescent-proliferation balance in organismal Ca2+ homeostasis and survival.

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The Anti-Atherogenic Properties of Sesamin are Mediated via Improved Macrophage Cholesterol Efflux Through PPARγ1-LXRα and MAPK Signaling

International Journal for Vitamin and Nutrition Research ◽

10.1024/0300-9831/a000195 ◽

2014 ◽

Vol 84 (1-2) ◽

pp. 79-91 ◽

Cited By ~ 7

Author(s):

Amin F. Majdalawieh ◽

Hyo-Sung Ro

Keyword(s):

Cholesterol Efflux ◽

Transcriptional Activity ◽

Molecular Mechanisms ◽

Foam Cell ◽

Mapk Signaling ◽

Luciferase Reporter ◽

Foam Cell Formation ◽

Dependent Manner ◽

Concentration Dependent Manner ◽

Macrophage Cholesterol Efflux

Background: Foam cell formation resulting from disrupted macrophage cholesterol efflux, which is triggered by PPARγ1 and LXRα, is a hallmark of atherosclerosis. Sesamin and sesame oil exert anti-atherogenic effects in vivo. However, the exact molecular mechanisms underlying such effects are not fully understood. Aim: This study examines the potential effects of sesamin (0, 25, 50, 75, 100 μM) on PPARγ1 and LXRα expression and transcriptional activity as well as macrophage cholesterol efflux. Methods: PPARγ1 and LXRα expression and transcriptional activity are assessed by luciferase reporter assays. Macrophage cholesterol efflux is evaluated by ApoAI-specific cholesterol efflux assays. Results: The 50 μM, 75 μM, and 100 μM concentrations of sesamin up-regulated the expression of PPARγ1 (p< 0.001, p < 0.001, p < 0.001, respectively) and LXRα (p = 0.002, p < 0.001, p < 0.001, respectively) in a concentration-dependent manner. Moreover, 75 μM and 100 μM concentrations of sesamin led to 5.2-fold (p < 0.001) and 6.0-fold (p<0.001) increases in PPAR transcriptional activity and 3.9-fold (p< 0.001) and 4.2-fold (p < 0.001) increases in LXR transcriptional activity, respectively, in a concentration- and time-dependent manner via MAPK signaling. Consistently, 50 μM, 75 μM, and 100 μM concentrations of sesamin improved macrophage cholesterol efflux by 2.7-fold (p < 0.001), 4.2-fold (p < 0.001), and 4.2-fold (p < 0.001), respectively, via MAPK signaling. Conclusion: Our findings shed light on the molecular mechanism(s) underlying sesamins anti-atherogenic effects, which seem to be due, at least in part, to its ability to up-regulate PPARγ1 and LXRα expression and transcriptional activity, improving macrophage cholesterol efflux. We anticipate that sesamin may be used as a therapeutic agent for treating atherosclerosis.

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The apple C2H2-type zinc finger transcription factor MdZAT10 positively regulates JA-induced leaf senescence by interacting with MdBT2

Horticulture Research ◽

10.1038/s41438-021-00593-0 ◽

2021 ◽

Vol 8 (1) ◽

Author(s):

Kuo Yang ◽

Jian-Ping An ◽

Chong-Yang Li ◽

Xue-Na Shen ◽

Ya-Jing Liu ◽

...

Keyword(s):

Mass Spectrometry ◽

Transcription Factor ◽

Liquid Chromatography ◽

Zinc Finger ◽

Leaf Senescence ◽

Transcriptional Activity ◽

Molecular Mechanisms ◽

Liquid Chromatography Mass Spectrometry ◽

Zinc Finger Transcription Factor ◽

Insight Into

AbstractJasmonic acid (JA) plays an important role in regulating leaf senescence. However, the molecular mechanisms of leaf senescence in apple (Malus domestica) remain elusive. In this study, we found that MdZAT10, a C2H2-type zinc finger transcription factor (TF) in apple, markedly accelerates leaf senescence and increases the expression of senescence-related genes. To explore how MdZAT10 promotes leaf senescence, we carried out liquid chromatography/mass spectrometry screening. We found that MdABI5 physically interacts with MdZAT10. MdABI5, an important positive regulator of leaf senescence, significantly accelerated leaf senescence in apple. MdZAT10 was found to enhance the transcriptional activity of MdABI5 for MdNYC1 and MdNYE1, thus accelerating leaf senescence. In addition, we found that MdZAT10 expression was induced by methyl jasmonate (MeJA), which accelerated JA-induced leaf senescence. We also found that the JA-responsive protein MdBT2 directly interacts with MdZAT10 and reduces its protein stability through ubiquitination and degradation, thereby delaying MdZAT10-mediated leaf senescence. Taken together, our results provide new insight into the mechanisms by which MdZAT10 positively regulates JA-induced leaf senescence in apple.

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PRMT5 Promotes EMT Through Regulating Akt Activity in Human Lung Cancer

Cell Transplantation ◽

10.1177/09636897211001772 ◽

2021 ◽

Vol 30 ◽

pp. 096368972110017

Author(s):

Jianhao Huang ◽

Yonghua Zheng ◽

Xiao Zheng ◽

Bao Qian ◽

Qi Yin ◽

...

Keyword(s):

Lung Cancer ◽

Cancer Cells ◽

Molecular Mechanisms ◽

Human Lung ◽

Akt Signaling ◽

Lung Cancer Cells ◽

Signaling Cascades ◽

Human Lung Cancer ◽

Mesenchymal Transition ◽

Human Lung Cancer Cells

The type II protein arginine methyltransferase 5 (PRMT5) has been engaged in various human cancer development and progression types. Nevertheless, few studies uncover the biological functions of PRMT5 in the epithelial-mesenchymal transition (EMT) of human lung cancer cells, and the associated molecular mechanisms and signaling cascades are entirely unknown. Here, we show that PRMT5 is the ectopic expression in human lung cancer tissues and cell lines. Further study reveals that silencing PRMT5 by lentivirus-mediated shRNA or blocking of PRMT5 by specific inhibitor GSK591 attenuates the expression levels of EMT-related markers in vivo, using the xenograft mouse model. Moreover, our results show that down-regulation of PRMT5 impairs EGFR/Akt signaling cascades in human lung cancer cells, whereas re-expression of PRMT5 recovers those changes, suggesting that PRMT5 regulates EMT probably through EGFR/Akt signaling axis. Altogether, our results demonstrate that PRMT5 serves as a critical oncogenic regulator and promotes EMT in human lung cancer cells. More importantly, our findings also suggest that PRMT5 may be a potential therapeutic candidate for the treatment of human lung cancer.

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R-Ras Controls Membrane Protrusion and Cell Migration through the Spatial Regulation of Rac and Rho

Molecular Biology of the Cell ◽

10.1091/mbc.e04-04-0277 ◽

2005 ◽

Vol 16 (1) ◽

pp. 84-96 ◽

Cited By ~ 63

Author(s):

Michele A. Wozniak ◽

Lina Kwong ◽

David Chodniewicz ◽

Richard L. Klemke ◽

Patricia J. Keely

Keyword(s):

Cell Migration ◽

Molecular Mechanisms ◽

Leading Edge ◽

Pi3 Kinase ◽

Dominant Negative ◽

Cell Periphery ◽

Membrane Protrusion ◽

Spatial Regulation ◽

Entire Cell ◽

Migratory Cells

Although it is known that the spatial coordination of Rac and Rho activity is essential for cell migration, the molecular mechanisms regulating these GTPases during migration are unknown. We found that the expression of constitutively activated R-Ras (38V) blocked membrane protrusion and random migration. In contrast, expression of dominant negative R-Ras (41A) enhanced migrational persistence and membrane protrusion. Endogenous R-Ras is necessary for cell migration, as cells that were transfected with siRNA for R-Ras did not migrate. Expression of R-Ras (38V) decreased Rac activity and increased Rho activity around the entire cell periphery, whereas expression of dominant negative R-Ras (41A) showed the converse, suggesting that R-Ras can spatially activate Rho and inactivate Rac. Consistent with this role, endogenous R-Ras localized and was preferentially activated at the leading edge of migratory cells in response to adhesion. The effects of R-Ras on cell migration are mediated by PI3-Kinase, as an effector mutant that uncouples PI3-Kinase binding from R-Ras (38V) rescued migration. From these data, we hypothesize that R-Ras plays a key role in cell migration by locally regulating the switch from Rac to Rho activity after membrane protrusion and adhesion.

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Regulation of β myosin heavy chain, c-myc and c-fos proto-oncogenes in thyroid hormone-induced hypertrophy of the rat myocardium

Clinical Science ◽

10.1042/cs0840061 ◽

1993 ◽

Vol 84 (1) ◽

pp. 61-67 ◽

Cited By ~ 9

Author(s):

N. K. Green ◽

M. D. Gammage ◽

J. A. Franklyn ◽

A. M. Heagerty ◽

M. C. Sheppard

Keyword(s):

Thyroid Hormone ◽

Right Ventricular ◽

Myosin Heavy Chain ◽

Heavy Chain ◽

Molecular Mechanisms ◽

Left Ventricular ◽

Transcriptional Level ◽

Messenger Rnas ◽

Hypertrophic Response ◽

Left And Right

1. In order to investigate the molecular mechanisms determining the hypertrophic response of the ventricular myocardium to thyroid hormone administration, changes in left and right ventricular expression of the c-myc, c-fos and H-ras proto-oncogenes in response to treatment with 3,3′,5-tri-iodothyronine were defined. 2. Adult female Wistar rats were treated with daily subcutaneous injections of 3,3′,5-tri-iodothyronine (50 μg) for 1, 3, 7 or 14 days (n = 6 in each treatment group) and the results from 3,3′,5-tri-iodothyronine-treated animals were compared with those obtained from untreated controls (n = 6). Changes in the weight of the left and right ventricles in response to 3,3′,5-tri-iodothyronine treatment were measured; changes in expression of the c-myc, c-fos and H-ras proto-oncogenes were determined in parallel by measurement of specific messenger RNAs by Northern and dot hybridization, as well as changes in expression of β myosin heavy chain messenger RNA. 3. Treatment with 3,3′,5-tri-iodothyronine resulted in increases in both left and right ventricular weights after 3 days, an effect maintained up to 14 days. Despite an increase in left ventricular weight, levels of β myosin heavy chain, c-myc, c-fos and H-ras mRNAs in the left ventricle were unchanged; in contrast, an increase in right ventricular weight was associated with increased expression of β myosin heavy chain, c-myc and c-fos messenger RNAs. 4. These specific ventricular changes in gene expression, in the face of a hypertrophic response of both ventricles to 3,3′,5-tri-iodothyronine, suggest that the cardiac growth response to thyroid hormones reflects the well-documented secondary haemodynamic influences rather than direct gene regulatory actions of 3,3′,5-tri-iodothyronine at the transcriptional level on the genes studied. Changes in right ventricular proto-oncogene and β myosin heavy chain expression may in turn reflect an increase in right ventricular pressure load.

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Clinical Importance of Wnt5a in the Pathogenesis of Colorectal Cancer

Journal of Oncology ◽

10.1155/2021/3136508 ◽

2021 ◽

Vol 2021 ◽

pp. 1-8

Author(s):

Mehran Pashirzad ◽

Thozhukat Sathyapalan ◽

Amirhossein Sahebkar

Keyword(s):

Colorectal Cancer ◽

Molecular Mechanisms ◽

Potential Role ◽

Clinical Importance ◽

Signaling Cascades ◽

Cancer Type ◽

Invasion And Metastasis ◽

Cellular Processes ◽

Wnt5a Expression ◽

Noncanonical Signaling

Wnt5a is one of the potent signaling molecules that initiates responses involved in cancer through activation of both canonical and noncanonical signaling cascades. Wnt5a both directly and indirectly triggers cancer-associated signaling pathways based on the cancer type. In colorectal cancer (CRC), altering Wnt5a expression can influence several cellular processes of tumor cells, including proliferation, differentiation, migration, invasion, and metastasis. This review summarizes the molecular mechanisms and clinical importance of Wnt5a in the pathogenesis of CRC for better understanding the pathogenesis and its potential role as a prognostic marker and as an appropriate therapeutic target in the treatment of this disease in the future.

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Epigenetic regulations follow cell cycle progression during differentiation of human pluripotent stem cells

10.1101/2020.06.26.173211 ◽

2020 ◽

Author(s):

Pedro Madrigal ◽

Siim Pauklin ◽

Kim Jee Goh ◽

Rodrigo Grandy ◽

Anna Osnato ◽

...

Keyword(s):

Cell Cycle ◽

Stem Cells ◽

Cell Fate ◽

Cell Cycle Progression ◽

Molecular Mechanisms ◽

Embryonic Stem ◽

Chromatin Accessibility ◽

Activator Protein 1 ◽

Cellular Division ◽

Mapk Signalling

AbstractMost mammalian stem cells undergo cellular division during their differentiation to produce daughter cells with a new cellular identity. However, the cascade of epigenetic events and molecular mechanisms occurring between successive cell divisions upon differentiation have not yet been described in detail due to technical limitations. Here, we address this question by taking advantage of the Fluorescent Ubiquitination-based Cell Cycle Indicator (FUCCI) reporter to develop a culture system allowing the differentiation of human Embryonic Stem Cells (hESCs) synchronised for their cell cycle. Using this approach, we have assessed the epigenome and transcriptome dynamics during the first two divisions leading to definitive endoderm. We first observed that transcription of key markers of differentiation occurs before division suggesting that differentiation is initiated during the progression of cell cycle. Furthermore, ATAC-seq shows a major decrease in chromatin accessibility after pluripotency exit indicating that the first event of differentiation is the inhibition of alternative cell fate. In addition, using digital genomic footprinting we identified novel cell cycle-specific transcription factors with regulatory potential in endoderm specification. Of particular interest, Activator protein 1 (AP-1) controlled p38/MAPK signalling seems to be necessary for blocking endoderm shifting cell fate toward mesoderm lineage. Finally, histone modifications analyses suggest a temporal order between different marks. We can also conclude that enhancers are dynamically and rapidly established / decommissioned between different cell cycle upon differentiation. Overall, these data not only reveal key the successive interplays between epigenetic modifications during differentiation but also provide a valuable resource to investigate novel mechanisms in germ layer specification.

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The multi-site docking protein Grb2-associated binder 1 (Gab1) enhances interleukin-6-induced MAPK-pathway activation in an SHP2-, Grb2-, and time-dependent manner

Cell Communication and Signaling ◽

10.1186/s12964-019-0451-2 ◽

2019 ◽

Vol 17 (1) ◽

Cited By ~ 2

Author(s):

Hannes Bongartz ◽

Karen Gille ◽

Wiebke Hessenkemper ◽

Katharina Mandel ◽

Marc Lewitzky ◽

...

Keyword(s):

Interleukin 6 ◽

Molecular Mechanisms ◽

Mapk Pathway ◽

Sh2 Domain ◽

Time Dependent ◽

Signalling Pathways ◽

Dependent Manner ◽

Mapk Activation ◽

Pathway Activation ◽

Mapk Signalling

Abstract Background Cytokine-dependent activation of signalling pathways is tightly orchestrated. The spatiotemporal activation of signalling pathways dictates the specific physiological responses to cytokines. Dysregulated signalling accounts for neoplastic, developmental, and inflammatory diseases. Grb2-associated binder (Gab) family proteins are multi-site docking proteins, which expand cytokine-induced signal transduction in a spatial- and time-dependent manner by coordinating the recruitment of proteins involved in mitogen activated protein kinase (MAPK)/extracellular-signal regulated kinase (ERK) and phosphatidyl-inositol-3-kinase (PI3K) signalling. Interaction of Gab family proteins with these signalling proteins determines strength, duration and localization of active signalling cascades. However, the underlying molecular mechanisms of signal orchestration by Gab family proteins in IL-6-induced signalling are only scarcely understood. Methods We performed kinetic analyses of interleukin-6 (IL-6)-induced MAPK activation and analysed downstream responses. We compared signalling in wild-type cells, Gab1 knock-out cells, those reconstituted to express Gab1 mutants, and cells expressing gp130 receptors or receptor mutants. Results Interleukin-6-induced MAPK pathway activation can be sub-divided into an early Gab1-independent and a subsequent Gab1-dependent phase. Early Gab1-independent MAPK activation is critical for the subsequent initiation of Gab1-dependent amplification of MAPK pathway activation and requires binding of SH2 domain-containing phosphatase 2 (SHP2) to the interleukin-6 receptor complex. Subsequent and coordinated recruitment of Grb2 and SHP2 to Gab1 is essential for Gab1-dependent amplification of IL-6-induced late MAPK pathway activation and subsequent gene expression. Conclusions Overall, we elaborated the molecular requirements for Gab1-dependent, spatiotemporal orchestration of interleukin-6-dependent MAPK signalling. We discriminated IL-6-induced Gab1-independent, early activation of MAPK signalling and Gab1-dependent, sustained activation of MAPK signalling.

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Sp1 and Smad transcription factors co-operate to mediate TGF-β-dependent activation of amyloid-β precursor protein gene transcription

Biochemical Journal ◽

10.1042/bj20040682 ◽

2004 ◽

Vol 383 (2) ◽

pp. 393-399 ◽

Cited By ~ 45

Author(s):

Fabian DOCAGNE ◽

Cecilia GABRIEL ◽

Nathalie LEBEURRIER ◽

Sylvain LESNÉ ◽

Yannick HOMMET ◽

...

Keyword(s):

Transcription Factor ◽

Transcriptional Activity ◽

Molecular Mechanisms ◽

Transforming Growth Factor ◽

Amyloid Β ◽

Transforming Growth Factor Β ◽

Precursor Protein ◽

Transcriptional Level ◽

Amyloid Β Peptide ◽

Aβ Amyloid

Abnormal deposition of Aβ (amyloid-β peptide) is one of the hallmarks of AD (Alzheimer's disease). This peptide results from the processing and cleavage of its precursor protein, APP (amyloid-β precursor protein). We have demonstrated previously that TGF-β (transforming growth factor-β), which is overexpressed in AD patients, is capable of enhancing the synthesis of APP by astrocytes by a transcriptional mechanism leading to the accumulation of Aβ. In the present study, we aimed at further characterization of the molecular mechanisms sustaining this TGF-β-dependent transcriptional activity. We report the following findings: first, TGF-β is capable of inducing the transcriptional activity of a reporter gene construct corresponding to the +54/+74 region of the APP promoter, named APPTRE (APP TGF-β-responsive element); secondly, although this effect is mediated by a transduction pathway involving Smad3 (signalling mother against decapentaplegic peptide 3) and Smad4, Smad2 or other Smads failed to induce the activity of APPTRE. We also observed that the APPTRE sequence not only responds to the Smad3 transcription factor, but also the Sp1 (signal protein 1) transcription factor co-operates with Smads to potentiate the TGF-β-dependent activation of APP. TGF-β signalling induces the formation of nuclear complexes composed of Sp1, Smad3 and Smad4. Overall, the present study gives new insights for a better understanding of the fine molecular mechanisms occurring at the transcriptional level and regulating TGF-β-dependent transcription. In the context of AD, our results provide additional evidence for a key role for TGF-β in the regulation of Aβ production.

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