scholarly journals Post-translational regulation of the RpoS and PsrA genes in pseudomonas putida WCS358: The role of ClpXP protease

2008 ◽  
Vol 60 (1) ◽  
pp. 1-4
Author(s):  
B. Jovcic ◽  
Jelena Begovic ◽  
Jelena Lozo ◽  
Lj. Topisirovic ◽  
M. Kojic
Keyword(s):  
Western Blot ◽  
Pseudomonas Putida ◽  
Blot Analysis ◽  
Western Blot Analysis ◽  
Translational Regulation ◽  
Stationary Phases ◽  
Transcriptional Regulators ◽  
Exponential Phase ◽  
Early Exponential Phase

The RpoS and PsrA proteins are key transcriptional regulators that are activated in response to the stationary phase of growth in pseudomonads. This study was designed to establish whether ClpXP (ATP-dependent serine protease) regulates levels of RpoS and PsrA in Pseudomonas putida WCS358. Western blot analysis of P. putida WCS358 protein extracts from the early exponentianl, late exponential, and stationary phases of growth with antibodies against RpoS and PsrA revealed that these proteins are degraded by ClpXP in the early exponential phase of growth. The obtained results demonstrate a role for ClpXP protease in post-translational regulation of proteins encoded by the rpoS and psrA genes in Pseudomonas spp.

Abstract 255: Cytoprotective Effects of Erythropoietin and Erythropoietin-derivatives in Ischaemic Human Myotubes and the Role of Pi3k/akt Signalling Pathway

2013 ◽  
Vol 33 (suppl_1) ◽  
Author(s):  
Rebekah Sian Hwee Yu ◽  
Daryll Baker ◽  
David Abraham ◽  
Janice Tsui
Keyword(s):  
Skeletal Muscle ◽  
Western Blot ◽  
Blot Analysis ◽  
Western Blot Analysis ◽  
Caspase 3 ◽  
Signalling Pathway ◽  
Critical Limb Ischaemia ◽  
Human Myotubes ◽  
Muscle Biopsies

Objectives Erythropoietin (Epo) has tissue-protective effects in response to injury, acting through the EpoR-βcR heteroreceptor. We have previously demonstrated the presence and interaction of the EpoR and βcR in human skeletal muscle. Here we aim to investigate the potential cytoprotective effects of Epo and an Epo-derivative (ARA-290) in a human in vitro model of skeletal muscle and establish a potential downstream signalling pathway utilised in protecting cells from apoptosis (including Jak-2, PI3k/Akt, NFkB). Methods Gastrocnemius muscle biopsies were obtained from patients with critical limb ischaemia and control samples were obtained from non-ischaemic patients. Human myoblasts were isolated from muscle biopsies, cultured, and allowed to differentiate into myotubes in order to investigate the cytoprotective effects of Epo and ARA-290 on myotubes subjected to simulated ischaemia. The PI3k inhibitors, LY294002 and wortmannin, were then used to determine the role of PI3k/Akt pathway in mediating cytoprotection. Following this, inhibitors against the upstreatm (Jak-2) and downstream (NFkB) molecules were also investigated. Western blot analysis, using the pro-apoptotic marker cleaved caspase-3 was performed and compared with levels of Akt and phosphorylated-Akt, using western blot analysis. Results Exogenous administration of Epo and ARA-290 were able to ameliorate the ischaemia-induced apoptosis on isolated human myotubes as shown by a significant reduction in cleaved caspase-3 expression. Addition of all inhibitors, to ARA-290 or Epo pre-treated cells, abolished the reduction in apoptosis. Conclusion The ability of ARA-290 to attenuate apoptosis in human myotubes undergoing ischaemic insult suggests a potential role in tissue protection in skeletal muscle injury. We propose that the PI3k/Akt signalling pathway is involved in mediating this cytoprotection.

TIPE1 suppresses the invasion and migration of breast cancer cells and inhibits epithelial-to-mesenchymal transition primarily via the ERK signaling pathway

2019 ◽  
Vol 51 (10) ◽  
pp. 1008-1015 ◽  
Author(s):  
Shusheng Qiu ◽  
Wei Hu ◽  
Qiuhong Ma ◽  
Yi Zhao ◽  
Liang Li ◽  
...  
Keyword(s):  
Breast Cancer ◽  
Western Blot ◽  
Cancer Cells ◽  
Blot Analysis ◽  
Western Blot Analysis ◽  
Breast Cancer Cells ◽  
Mesenchymal Transition ◽  
Invasion And Migration ◽  
And Migration

Abstract Tumor necrosis factor α-induced protein 8-like-1 (TIPE1) functions as an activator or a repressor in a tumor cell type-specific manner. However, the role of TIPE1 in breast cancer, especially regarding metastasis, is unknown. In this study, we aimed to investigate the TIPE1 expression in breast cancer tissues, the biological functions, and the underlying mechanisms of TIPE1 regarding the metastatic properties of breast cancer cells. The results of immunohistochemical staining and western blot analysis indicated that TIPE1 expression was associated with tumor size and lymph node metastasis, and the expression of TIPE1 was downregulated in the tissues of patients with lymph node metastasis. Transwell and wound healing assay results showed that TIPE1 inhibited the invasive and migratory capacities of breast cancer cells. Moreover, the epithelial-mesenchymal transition (EMT) was suppressed in TIPE1-overexpressing cells, as demonstrated by western blot analysis. In addition, western blot analysis also showed that TIPE1 reduced the expression levels of MMP2 and MMP9 and decreased the phosphorylation level of ERK. These results suggested that TIPE1 might suppress the invasion and migration of breast cancer cells and inhibit EMT primarily via the ERK signaling pathway. Our findings revealed the anti-tumor metastasis role of TIPE1 in breast cancer and TIPE1 might be a new candidate prognostic indicator and a potential molecular target for the treatment of breast cancer.

scholarly journals Primary cilia respond to intermittent low-magnitude, high-frequency vibration and mediate vibration-induced effects in osteoblasts

2020 ◽  
Vol 318 (1) ◽  
pp. C73-C82 ◽  
Author(s):  
Yan-Hui Li ◽  
Dong Zhu ◽  
Zongbing Cao ◽  
Yanwei Liu ◽  
Jian Sun ◽  
...  
Keyword(s):  
Western Blot ◽  
Blot Analysis ◽  
High Frequency ◽  
Western Blot Analysis ◽  
Primary Cilia ◽  
Critical Role ◽  
Rt Pcr ◽  
High Frequency Vibration ◽  
Low Magnitude

Our objective was to investigate the role of primary cilia in low-magnitude, high-frequency vibration (LMHFV) treatment of MC3T3-E1 osteoblasts (OBs). We used chloral hydrate (CH), which has a well-characterized function in chemically removing primary cilia, to elucidate the role of primary cilia in LMHFV-induced OB osteogenic responses through cell viability assay, Western blot analysis, real-time quantitative RT-PCR, and histochemical staining methods. We observed a significant, 30% decrease in the number of MC3T3-E1 OBs with primary cilia (reduced from 64.3 ± 5%) and an approximately 50% reduction in length of primary cilia (reduced from 3 ± 0.8 μm) after LMHFV stimulation. LMHFV stimulation upregulated protein expression of the bone matrix markers collagen 1 (COL-1), osteopontin (OPN), and osteoclacin(OCN) in MC3T3-E1 OBs, indicating that LMHFV induces osteogenesis. High-concentration or long-duration CH exposure resulted in inhibition of MC3T3-E1 OB survival. In addition, Western blot analysis and RT-PCR revealed that CH treatment prevented LMHFV-induced osteogenesis. Furthermore, decreased alkaline phosphate activity, reduced OB differentiation, mineralization, and maturation were observed in CH-pretreated and LMHFV-treated OBs. We showed that LMHFV induces morphological changes in primary cilia that may fine-tune their mechanosensitivity. In addition, we demonstrated the significant inhibition by CH of LMHFV-induced OB mineralization, maturation, and differentiation, which might reveal the critical role of primary cilia in the process.

scholarly journals The diurnal pattern of salivary IL-1β in healthy young adults

2017 ◽  
Vol 31 (5) ◽  
Author(s):  
Nur Basirah Ghazali ◽  
Michael Steele ◽  
David Koh ◽  
Adi Idris
Keyword(s):  
Young Adults ◽  
Circadian Rhythm ◽  
Western Blot ◽  
Blot Analysis ◽  
Western Blot Analysis ◽  
Inflammatory Cytokine ◽  
Enzyme Linked Immunosorbent Assay ◽  
Diurnal Pattern ◽  
Healthy Individuals

Abstract Disruption in circadian rhythm affects the production of inflammatory cytokines. Understanding how it behaves in diseased conditions is essential. Despite the role of the interleukin-1β (IL-1β), a potent inflammatory cytokine, in human diseases, little is known about the steady-state circadian rhythm of IL-1β in healthy individuals. This short study investigates the diurnal pattern of salivary IL-1β throughout the day in healthy young adults. Twelve participants provided saliva samples at various times throughout the day. Salivary IL-1β were assessed using enzyme-linked immunosorbent assay (ELISA) and Western blot analysis. Salivary IL-1β levels were highest at 0430 h and lowest at 0000 h and shared a similar diurnal pattern to that of salivary IL-6. Western blot analysis showed that these levels correspond to the mature form of IL-1β. Our findings are important as it established the diurnal pattern of salivary IL-1β is fluctuating normally throughout the day. The findings also open an incredible opportunity for developing research conducted in the field with saliva as the diagnostic tool.

FGF-7 facilitates the process of psoriasis by inducing TNF-α expression in HaCaT cells

2019 ◽  
Vol 51 (10) ◽  
pp. 1056-1063 ◽  
Author(s):  
Jiaojiao Pu ◽  
Rui Wang ◽  
Guanglin Zhang ◽  
Ju Wang
Keyword(s):  
Western Blot ◽  
Signaling Pathway ◽  
Specific Antibody ◽  
Blot Analysis ◽  
Western Blot Analysis ◽  
Quantitative Polymerase Chain Reaction ◽  
Hacat Cells ◽  
Tnf Α

Abstract The purpose of this study was to uncover the mechanism of tumor necrosis factor (TNF)-α induction by fibroblast growth factor-7 (FGF-7) in human HaCaT cells and the potential role of FGF-7-specific antibody F-9 in psoriatic therapy. TNF-α expression in HaCaT cells induced by FGF-7 was analyzed by quantitative polymerase chain reaction, western blot analysis, and enzyme-linked immunosorbent assays. In vivo, the BALB/c mouse psoriasis model established by topical application of imiquimod (IMQ) was used to determine the role of FGF-7-specific antibody (F-9) in skin inflammation. We found that induction of TNF-α expression by FGF-7 in HaCaT cells was suppressed by FGF-7-specific antibody F-9. Western blot analysis results showed that FGF-7 induced TNF-α expression in HaCaT cells via the FGF receptor 2 (FGFR2)/AKT/NF-κB signaling pathway. In vivo, F-9 could significantly ameliorate the inflammations in a mouse psoriatic model evaluated by Psoriasis Area and Severity Index scores and ear thickness, which was consistent with the results of hematoxylin–eosin staining, immunohistochemistry assay, and western blot analysis. These results indicate that FGF-7 induces TNF-α expression in HaCaT cells and FGF-7 antibody F-9 alleviates IMQ-induced psoriasiform in mice. Therefore, FGF-7/FGFR2 signaling pathway is a potential target for psoriasis treatment.

Galectin-1 induces chemokine production and proliferation in pancreatic stellate cells

2006 ◽  
Vol 290 (4) ◽  
pp. G729-G736 ◽  
Author(s):  
Atsushi Masamune ◽  
Masahiro Satoh ◽  
Jun Hirabayashi ◽  
Kenichi Kasai ◽  
Kennichi Satoh ◽  
...  
Keyword(s):  
Western Blot ◽  
Blot Analysis ◽  
Western Blot Analysis ◽  
Stellate Cells ◽  
Pancreatic Tissue ◽  
Immunofluorescent Staining ◽  
Pancreatic Stellate Cells ◽  
Chemokine Production ◽  
Cell Functions

Galectin-1 is a β-galactoside-binding lectin. Previous studies have shown that galectin-1 was expressed in fibroblasts of chronic pancreatitis and of desmoplastic reaction associated with pancreatic cancer. These fibroblasts are now recognized as activated pancreatic stellate cells (PSCs). Here, we examined the role of galectin-1 in cell functions of PSCs. PSCs were isolated from rat pancreatic tissue and used in their culture-activated phenotype unless otherwise stated. Expression of galectin-1 was assessed by Western blot analysis, RT-PCR, and immunofluorescent staining. The effects of recombinant galectin-1 on chemokine production and proliferation were evaluated. Activation of transcription factors was assessed by EMSA. Activation of MAPKs was examined by Western blot analysis using anti-phosphospecific antibodies. Galectin-1 was strongly expressed in culture-activated but not freshly isolated PSCs. Recombinant galectin-1 increased proliferation and production of monocyte chemoattractant protein-1 and cytokine-induced neutrophil chemoattractant-1. Galectin-1 activated ERK, JNK, activator protein-1, and NF-κB, but not p38 MAPK or Akt. Galectin-1 induced proliferation through ERK and chemokine production mainly through the activation of NF-κB and in part by JNK and ERK pathways. These effects of galectin-1 were abolished in the presence of thiodigalactosie, an inhibitor of β-galactoside binding. In conclusion, our results suggest a role of galectin-1 in chemokine production and proliferation through its β-galactoside binding activity in activated PSCs.

scholarly journals The role of activating transcription factor 6 in hydroxycamptothecin-induced fibroblast autophagy and apoptosis

2021 ◽  
Vol 16 (1) ◽  
Author(s):  
Jin Tao ◽  
Hui Chen ◽  
Xiaolei Li ◽  
Jingcheng Wang
Keyword(s):  
Transcription Factor ◽  
Western Blot ◽  
Blot Analysis ◽  
Western Blot Analysis ◽  
Cell Counting ◽  
Immunofluorescent Staining ◽  
Fibroblast Proliferation ◽  
Activating Transcription Factor ◽  
Related Proteins

Abstract Background The over-proliferation of fibroblasts is considered to be the main cause of scar adhesion after joint surgery. Hydroxycamptothecin (HCPT), though as a potent antineoplastic drug, shows preventive effects on scar adhesion. This study aimed to investigate the role of activating transcription factor 6 (ATF-6) in the HCPT-induced inhibition of fibroblast viability. Methods The cell counting kit-8 (CCK-8) assay, western blot analysis, lentivirus-mediated gene silencing, transmission electron microscopy (TEM) analysis, immunofluorescent staining for autophagy-related protein light chain 3 (LC3) were used to explore the effect of HCPT on triggering fibroblast apoptosis and inhibiting fibroblast proliferation, and the involvement of possible signaling pathways. Results It was found that HCPT exacerbated fibroblast apoptosis and repressed its proliferation. Subsequently, endoplasmic reticulum stress (ERS)-related proteins were determined by western blot prior to ATF6 p50 was screened out and reexamined after it was silenced. As a result, ATF6-mediated ERS played a role in HCPT-induced fibroblast apoptosis. Autophagy-related proteins and autophagosomes were detected after the HCPT administration using western blot and TEM analyses, respectively. Autophagy was activated after the HCPT treatment. With the co-treatment of autophagy inhibitor 3-methyladenine (3-MA), both the western blot analysis and the CCK-8 assay showed inhibited autophagy, which indicated that the effect of HCPT on fibroblast proliferation was partially reversed. Besides, the LC3 immunofluorescence staining revealed suppressed autophagy after silencing ATF6 p50. Conclusion Our results demonstrate that HCPT acts as a facilitator of fibroblast apoptosis and inhibitor of fibroblast proliferation for curbing the postoperative scar adhesion, in which the ATF6-mediated ERS pathway and autophagy are involved.

scholarly journals Differential Role of Rapamycin in Epidermis-Induced IL-15-IGF-1 Secretion via Activation of Akt/mTORC2

2017 ◽  
Vol 42 (5) ◽  
pp. 1755-1768 ◽  
Author(s):  
Yang Bai ◽  
Rui Xu ◽  
Xueyuan Zhang ◽  
Xiaorong Zhang ◽  
Xiaohong Hu ◽  
...  
Keyword(s):  
Wound Healing ◽  
Western Blot ◽  
Blot Analysis ◽  
Western Blot Analysis ◽  
Low Dose ◽  
Underlying Mechanism ◽  
High Dose ◽  
Mtorc1 Pathway ◽  
Hematoxylin And Eosin

Backgroud/Aims: The effects of rapamycin (RPM) on wound healing have been previously studied. However, reciprocal contradictory data have been reported, and the underlying mechanism remains unclear. This study aims to uncover differential role of RPM in regulation of wound healing and explore the possible mechanism. Methods: C57BL/6J mice and epidermal cells were treated with different doses of RPM. The wound re-epithelialization was observed by hematoxylin and eosin (HE) staining. The expression of IL-15 and IGF-1 were detected by immunohistochemistry and quantitative real-time PCR. Epidermal cell survival was determined by CCK-8 assays. Moreover, the mTORC1 and mTORC2 pathway were examined by western blot analysis. Results: This study showed that differential doses of RPM could lead to separate consequences in epidermis. Histological analyses showed that low-dose RPM promoted wound healing, and enhanced the expression of IL-15 and IGF-1. Furthermore, western blot analysis showed that the effect of low-dose RPM in epidermis were not through mTORC1 pathway. Instead, activation of the Akt/mTORC2 pathway was involved in low-dose RPM-induced IL-15 and IGF-1 production in epidermis, while high-dose RPM inhibited the expression of IL-15 and IGF-1 and the activity of mTORC1 and mTORC2 pathway. Conclusion: This study for the first time demonstrated that RPM-mediated wound healing was dose-dependent.

scholarly journals Localization, Regulation and Possible Consequences of Apoptotic Protease-Activating Factor-1 (Apaf-1) Expression in Granulosa Cells of the Mouse Ovary

Endocrinology ◽  
1999 ◽  
Vol 140 (6) ◽  
pp. 2641-2644 ◽  
Author(s):  
Rodolfo Robles ◽  
Xiao-Jing Tao ◽  
Alexander M. Trbovich ◽  
Daniel V. Maravei ◽  
Ravit Nahum ◽  
...  
Keyword(s):  
Cell Death ◽  
Western Blot ◽  
Granulosa Cell ◽  
Granulosa Cells ◽  
Blot Analysis ◽  
Cell Apoptosis ◽  
Western Blot Analysis ◽  
C Elegans

Abstract The recent characterization of apoptotic protease-activating factor-1 (Apaf-1) in vertebrates as a putative homolog of the Caenorhabditis elegans gene, ced-4, indicates that the third major arm of the C. elegans programmed cell death machinery has also been conserved through evolution. Although apoptosis is now known to be important for ovarian follicular atresia in vertebrates, nothing is known of the role of Apaf-1 in ovarian function. Herein we show by immunohistochemical analysis that Apaf-1 is abundant in granulosa cells of early antral follicles whereas in vivo gonadotropin priming completely suppresses Apaf-1 expression and granulosa cell apoptosis. Western blot analysis of fractionated protein extracts prepared from granulosa cells before and after in vitro culture without hormonal support to induce apoptosis indicated that mitochondrial cytochrome c release, a biochemical step required for the activation of Apaf-1, occurs in granulosa cells cultured in vitro. Moreover, Western blot analysis of procaspase-3 processing, a principal downstream event set in motion by activated Apaf-1, indicated that healthy granulosa cells possess almost exclusively the inactive (pro-) form of the enzyme whereas granulosa cells deprived of hormonal support rapidly process procaspase-3 to the active enzyme. Lastly, we show that serum-starved granulosa cells activate caspase-3-like enzymes both prior to and after nuclear pyknosis, as revealed by a single-cell fluorescent caspase activity assay. These data, combined with previous observations regarding the role of homologs of the two other C. elegans cell death regulatory genes, ced-9 (Bc1-2 family members) and ced-3 (caspases), in atresia fully support the hypothesis that granulosa cell apoptosis is precisely coordinated by all three major arms of a cell death program conserved through evolution.

Overexpression of the EphB4 Receptor Contributes to Imatinib Resistance in Chronic Myeloid Leukemia Through Regulating Mlcp and VAV1

Blood ◽  
2012 ◽  
Vol 120 (21) ◽  
pp. 4421-4421
Author(s):  
Liu Xiaoli ◽  
Jinfang Zhang ◽  
Qingfeng Du ◽  
Na Xu ◽  
Lulu Xu ◽  
...  
Keyword(s):  
Cell Adhesion ◽  
Chronic Myeloid Leukemia ◽  
Western Blot ◽  
Cell Lines ◽  
Blot Analysis ◽  
Western Blot Analysis ◽  
Myeloid Leukemia ◽  
K562 Cells ◽  
Differential Expression Genes

Abstract Abstract 4421 Objective: To study the role of EphB4 in imatinib (IM) resistant chronic myeloid leukemia (CML) and investigate the mechanism. Methods: We derived IM-resistant cells, K562-R cells, from wild K562 cells under gradually increasing IM concentrations. We analysed expression level of EphB4 in CML patients, wild K562 and K562-R cell lines by real-time reverse transcription PCR and Western blot analysis. Then we established stable under-expressing EphB4 cell (K562-R-EphB4-sh) lines. We analysed the sensitive for IM of K562, K562-R, K562-R-EphB4-sh cell lines by CCK8 assay. Microarray analysis was used to screen differential expression genes between K562-R and K562-R-EphB4-sh cell lines. Results: The mRNA and protein of EphB4 were significantly increased in IM resistant CML patients compared to IM sensitive CML patients (p<0.05). The Similar results were observed in K562-R and K562 cells (p<0.01). To analyze the role of EphB4 in IM resistance, EphB4 was knocked down with shRNA expressed by pLL3.7 lentivirus vector. We established stable under-expressing EphB4 cell line K562-R-EphB4-sh. RT-PCR and western blot analysis showed that mRNA and protein expression of EphB4 in K562-R-EphB4-sh cells were reduced (p<0.05). CCK8 assay found K562 cells (IC50 0.1207±0.0234μM), K562-R-EphB4-sh cells (IC50 0.7228±0.04752μM) were sensitive to IM but K562-R (IC50 2.8101±0.04674μM) still showed IM resistance (p<0.05). Those suggested K562-R-EphB4-sh cells resensitize to IM when the expression of EphB4 was down regulated. However, these cells were still less sensitive than K562 cells. Microarray analysis between K562-R and K562-R-EphB4-sh cell lines found 641 differential expression genes, most of them were related to cell adhesion and cell cytoskeleton. We confirmed MLCP and VAV1 were down regulated in K562-R-EphB4-sh cells compared to K562-R cell lines by western blot analysis. Conclusion: Our study suggest EphB4 receptor contributes to IM-resistant in CML through regulating cell adhesion molecular MLCP and VAV1, which may provide new biomarkers and contribute to] developping new drugs for the disease. Disclosures: No relevant conflicts of interest to declare.

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