Regulation of Chitin-Dependent Growth and Natural Competence in Vibrio parahaemolyticus

Vibrios can degrade chitin surfaces to soluble N-acetyl glucosamine oligosaccharides (GlcNAcn) that can be utilized as a carbon source and also induce a state of natural genetic competence. In this study, we characterized chitin-dependent growth and natural competence in Vibrio parahaemolyticus and its regulation. We found that growth on chitin was regulated through chitin sensors ChiS (sensor histidine kinase) and TfoS (transmembrane transcriptional regulator) by predominantly controlling the expression of chitinase VPA0055 (ChiA2) in a TfoX-dependent manner. The reduced growth of ΔchiA2, ΔchiS and ΔtfoS mutants highlighted the critical role played by ChiA2 in chitin breakdown. This growth defect of ΔchiA2 mutant could be recovered when chitin oligosaccharides GlcNAc2 or GlcNAc6 were supplied instead of chitin. The ΔtfoS mutant was also able to grow on GlcNAc2 but the ΔchiS mutant could not, which indicates that GlcNAc2 catabolic operon is dependent on ChiS and independent of TfoS. However, the ΔtfoS mutant was unable to utilize GlcNAc6 because the periplasmic enzymes required for the breakdown of GlcNAc6 were found to be downregulated at the mRNA level. We also showed that natural competence can be induced only by GlcNAc6, not GlcNAc2, because the expression of competence genes was significantly higher in the presence of GlcNAc6 compared to GlcNAc2. Moreover, this might be an indication that GlcNAc2 and GlcNAc6 were detected by different receptors. Therefore, we speculate that GlcNAc2-dependent activation of ChiS and GlcNAc6-dependent activation of TfoS might be crucial for the induction of natural competence in V. parahaemolyticus through the upregulation of the master competence regulator TfoX.

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Genome-wide identification and characterization of transcripts translationally regulated by bacterial lipopolysaccharide in macrophage-like J774.1 cells

Physiological Genomics ◽

10.1152/physiolgenomics.00095.2007 ◽

2008 ◽

Vol 33 (1) ◽

pp. 121-132 ◽

Cited By ~ 18

Author(s):

Hiroshi Kitamura ◽

Masatoshi Ito ◽

Tomoko Yuasa ◽

Chisato Kikuguchi ◽

Atsushi Hijikata ◽

...

Keyword(s):

Nitric Oxide ◽

Respiratory Chain ◽

Mrna Level ◽

Critical Role ◽

Mitochondrial Respiratory Chain ◽

Mrna Levels ◽

Dependent Manner ◽

Genome Wide ◽

A Genome ◽

Mitochondrial Respiratory

Although Escherichia coli LPS is known to elicit various proinflammatory responses in macrophages, its effect on the translational states of transcripts has not yet been explored on a genome-wide scale. To address this, we investigated the mRNA profiles in polysomal and free messenger ribonucleoprotein particle (mRNP) fractions of mouse macrophage-like J774.1 cells, using Affymetrix Mouse Genome 430 2.0 GeneChips. Comparison of the mRNA profiles in total cellular, polysomal, and free mRNP fractions enabled us to identify transcripts that were modulated at the translational level by LPS: among 19,791 transcripts, 115 and 418 were up- and downregulated at 1, 2, or 4 h after LPS stimulation (100 ng/ml) in a translation-dependent manner. Interestingly, gene ontology-based analysis suggested that translation-dependent downregulated genes frequently include those encoding proteins in the mitochondrial respiratory chain. In fact, the mRNA levels of some transcripts for complexes I, IV, and V in the mitochondrial respiratory chain were translationally downregulated, eventually contributing to the decline of their protein levels. Moreover, the amount of metabolically labeled cytochrome oxidase subunit Va in complex IV was decreased without any change of its mRNA level in total cellular fraction after LPS stimulation. Consistently, the total amounts and activities of complexes I and IV were attenuated by LPS stimulation, and the attenuation was independent of nitric oxide. These results demonstrated that translational suppression may play a critical role in the LPS-mediated attenuation of mitochondrial oxidative phosphorylation in a nitric oxide-independent manner in J774.1 cells.

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Clearance of senescent decidual cells by uterine natural killer cells drives endometrial remodeling during the window of implantation

10.1101/172593 ◽

2017 ◽

Author(s):

Paul J Brighton ◽

Yojiro Maruyama ◽

Katherine Fishwick ◽

Pavle Vrljicak ◽

Shreeya Tewary ◽

...

Keyword(s):

Natural Killer ◽

Embryo Implantation ◽

Critical Role ◽

Dependent Manner ◽

Endometrial Stromal Cells ◽

Uterine Natural Killer Cells ◽

Decidual Cells ◽

Unk Cells ◽

Dependent Growth ◽

Uterine Natural Killer

SummaryIn cycling human endometrium, menstruation is followed by rapid estrogen-dependent growth. Upon ovulation, progesterone and rising cellular cAMP levels activate the transcription factor Forkhead box O1 (FOXO1) in endometrial stromal cells (EnSCs), leading to cell cycle exit and differentiation into decidual cells that control embryo implantation. Here we show that FOXO1 also causes acute senescence of a subpopulation of decidualizing EnSCs in an IL-8 dependent manner. Selective depletion or enrichment of this subpopulation revealed that decidual senescence drives the transient inflammatory response associated with endometrial receptivity. Further, senescent cells prevent differentiation of endometrial mesenchymal stem cells in decidualizing cultures. As the cycle progresses, IL-15 activated uterine natural killer (uNK) cells selectively target and clear senescent decidual cells through granule exocytosis. Our findings reveal that acute decidual senescence governs endometrial rejuvenation and remodeling at embryo implantation, and suggest a critical role for uNK cells in maintaining homeostasis in cycling endometrium.

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Effects of phosphodiesterase inhibitors on cytokine production by microglia

Multiple Sclerosis Journal ◽

10.1177/135245859900500210 ◽

1999 ◽

Vol 5 (2) ◽

pp. 126-133 ◽

Cited By ~ 59

Author(s):

Minka Yoshikawa ◽

Akio Suzumura ◽

Tsukasa Tamaru ◽

Tetsuya Takayanagi ◽

Makato Sawada

Keyword(s):

Neurological Diseases ◽

Interleukin 1 ◽

Mrna Level ◽

Critical Role ◽

Phosphodiesterase Inhibitors ◽

Dependent Manner ◽

Tnf Α ◽

The Central Nervous System ◽

Pass Through

Type III and IV phosphodiesterase inhibitors (PDEIs) have recently been shown to suppress the production of TNF-α in several types of cells. In the present study, we have shown that all the types of PDEIs, from type 1- to V-specific and non-specific, suppress the production of TNF-α by mouse microglia stimulated with lipopolysaccharide (LPS) in a dose-dependent manner. Certain combinations of three different types of PDEIs synergistically suppressed TNF-α production by microglia at a very low concentration (1 μM). Since some PDEIs reportedly pass through the blood-brain barrier (BBB), the combination of three PDEIs may be worth trying in neurological diseases, such as multiple sclerosis and HIV-related neurological diseases in which TNF-α may play a critical role. Some PDEIs also suppressed interleukin-1 (IL-1) and IL-6 production by mouse microglia stimulated with LPS. In contrast, the production of IL-10, which is known to be an inhibitory cytokine, was upregulated by certain PDEIs. The suppression of TNF-α and induction of IL-10 were confirmed at the mRNA level by RT - PCR. PDEIs may be useful anti-inflammatory agents by downregulating inflammatory cytokines and upregulating inhibitory cytokines in the central nervous system. (CNS).

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Homocysteine- and cysteine-mediated growth defect is not associated with induction of oxidative stress response genes in yeast

Biochemical Journal ◽

10.1042/bj20051411 ◽

2006 ◽

Vol 396 (1) ◽

pp. 61-69 ◽

Cited By ~ 49

Author(s):

Arun Kumar ◽

Lijo John ◽

Md. Mahmood Alam ◽

Ankit Gupta ◽

Gayatri Sharma ◽

...

Keyword(s):

Oxidative Stress ◽

Transcriptional Profiling ◽

Critical Role ◽

Transcriptional Response ◽

Growth Defect ◽

Disease Genes ◽

Dependent Manner ◽

Yeast Growth ◽

Concentration Dependent Manner ◽

Exogenous Addition

Intracellular thiols like cysteine, homocysteine and glutathione play a critical role in the regulation of important cellular processes. Alteration of intracellular thiol concentration results in many diseased states; for instance, elevated levels of homocysteine are considered to be an independent risk factor for cardiovascular disease. Yeast has proved to be an excellent model system for studying many human diseases since it carries homologues of nearly 40% of human disease genes and many fundamental pathways are highly conserved between the two organisms. In the present study, we demonstrate that cysteine and homocysteine, but not glutathione, inhibit yeast growth in a concentration-dependent manner. Using deletion strains (str2Δ and str4Δ) we show that cysteine and homocysteine independently inhibit yeast growth. Transcriptional profiling of yeast treated with cysteine and homocysteine revealed that genes coding for antioxidant enzymes like glutathione peroxidase, catalase and superoxide dismutase were down-regulated. Furthermore, transcriptional response to homocysteine did not show any similarity to the response to H2O2. We also failed to detect induction of reactive oxygen species in homocysteine- and cysteine-treated cells, using fluorogenic probes. These results indicate that homocysteine- and cysteine-induced growth defect is not due to the oxidative stress. However, we found an increase in the expression of KAR2 (karyogamy 2) gene, a well-known marker of ER (endoplasmic reticulum) stress and also observed HAC1 cleavage in homocysteine- and cysteinetreated cells, which indicates that homocysteine- and cysteine-mediated growth defect may probably be attributed to ER stress. Transcriptional profiling also revealed that genes involved in one-carbon metabolism, glycolysis and serine biosynthesis were up-regulated on exogenous addition of cysteine and homocysteine, suggesting that cells try to reduce the intracellular concentration of thiols by up-regulating the genes involved in their metabolism.

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The Effects of Butyric Acid on the Differentiation, Proliferation, Apoptosis, and Autophagy of IPEC-J2 Cells

Current Molecular Medicine ◽

10.2174/1566524019666191024110443 ◽

2020 ◽

Vol 20 (4) ◽

pp. 307-317

Author(s):

Yuan Yang ◽

Jin Huang ◽

Jianzhong Li ◽

Huansheng Yang ◽

Yulong Yin

Keyword(s):

Cell Viability ◽

P38 Mapk ◽

Butyric Acid ◽

Cell Apoptosis ◽

Mapk Pathway ◽

Mrna Level ◽

Dependent Manner ◽

M Phase ◽

High Concentrations ◽

Underlying Mechanisms

Background: Butyric acid (BT), a short-chain fatty acid, is the preferred colonocyte energy source. The effects of BT on the differentiation, proliferation, and apoptosis of small intestinal epithelial cells of piglets and its underlying mechanisms have not been fully elucidated. Methods: In this study, it was found that 0.2-0.4 mM BT promoted the differentiation of procine jejunal epithelial (IPEC-J2) cells. BT at 0.5 mM or higher concentrations significantly impaired cell viability in a dose- and time-dependent manner. In addition, BT at high concentrations inhibited the IPEC-J2 cell proliferation and induced cell cycle arrest in the G2/M phase. Results: Our results demonstrated that BT triggered IPEC-J2 cell apoptosis via the caspase8-caspase3 pathway accompanied by excess reactive oxygen species (ROS) and TNF-α production. BT at high concentrations inhibited cell autophagy associated with increased lysosome formation. It was found that BT-reduced IPEC-J2 cell viability could be attenuated by p38 MAPK inhibitor SB202190. Moreover, SB202190 attenuated BT-increased p38 MAPK target DDIT3 mRNA level and V-ATPase mRNA level that were responsible for normal acidic lysosomes. Conclusion: In conclusion, 1) at 0.2-0.4 mM, BT promotes the differentiation of IPEC-J2 cells; 2) BT at 0.5 mM or higher concentrations induces cell apoptosis via the p38 MAPK pathway; 3) BT inhibits cells autophagy and promotes lysosome formation at high concentrations.

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The Natural Flavonoid Naringenin Inhibits the Cell Growth of WilmsTumorinChildren by Suppressing TLR4/NF-κB Signaling

Anti-Cancer Agents in Medicinal Chemistry ◽

10.2174/1871520620999200818155814 ◽

2020 ◽

Vol 20 ◽

Author(s):

Hongtao Li ◽

Peng Chen ◽

Lei Chen ◽

Xinning Wang

Keyword(s):

Cell Growth ◽

Western Blot ◽

Wilms Tumor ◽

Critical Role ◽

Time Dependent ◽

Luciferase Assay ◽

Dependent Manner ◽

Tlr4 Expression ◽

Protein Levels

Background: Nuclear factor kappa B (NF-κB) is usually activated in Wilms tumor (WT) cells and plays a critical role in WT development. Objective: The study purpose was to screen a NF-κB inhibitor from natural product library and explore its effects on WT development. Methods: Luciferase assay was employed to assess the effects of natural chemical son NF-κB activity. CCK-8 assay was conducted to assess cell growth in response to naringenin. WT xenograft model was established to analyze the effect of naringenin in vivo. Quantitative real-time PCR and Western blot were performed to examine the mRNA and protein levels of relative genes, respectively. Results: Naringenin displayed significant inhibitory effect on NF-κB activation in SK-NEP-1 cells. In SK-NEP-1 and G-401 cells, naringenin inhibited p65 phosphorylation. Moreover, naringenin suppressed TNF-α-induced p65 phosphorylation in WT cells. Naringenin inhibited TLR4 expression at both mRNA and protein levels in WT cells. CCK-8 staining showed that naringenin inhibited cell growth of the two above WT cells in dose-and time-dependent manner, whereas Toll-like receptor 4 (TLR4) over expression partially reversed the above phenomena. Besides, naringenin suppressed WT tumor growth in dose-and time-dependent manner in vivo. Western blot found that naringenin inhibited TLR4 expression and p65 phosphorylation in WT xenograft tumors. Conclusion: Naringenin inhibits WT development viasuppressing TLR4/NF-κB signaling

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Genome-wide CRISPR/Cas9 screening identifies CARHSP1 responsible for radiation resistance in glioblastoma

Cell Death and Disease ◽

10.1038/s41419-021-04000-3 ◽

2021 ◽

Vol 12 (8) ◽

Author(s):

Guo-dong Zhu ◽

Jing Yu ◽

Zheng-yu Sun ◽

Yan Chen ◽

Hong-mei Zheng ◽

...

Keyword(s):

Cold Shock ◽

Mrna Level ◽

Critical Role ◽

Inflammatory Signaling ◽

Heat Stable ◽

Genome Wide ◽

Attractive Therapeutic Target ◽

Heat Stable Protein ◽

Signaling Activation ◽

Shock Proteins

AbstractGlioblastomas (GBM) is the most common primary malignant brain tumor, and radiotherapy plays a critical role in its therapeutic management. Unfortunately, the development of radioresistance is universal. Here, we identified calcium-regulated heat-stable protein 1 (CARHSP1) as a critical driver for radioresistance utilizing genome-wide CRISPR activation screening. This is a protein with a cold-shock domain (CSD)-containing that is highly similar to cold-shock proteins. CARHSP1 mRNA level was upregulated in irradiation-resistant GBM cells and knockdown of CARHSP1 sensitized GBM cells to radiotherapy. The high expression of CARHSP1 upon radiation might mediate radioresistance by activating the inflammatory signaling pathway. More importantly, patients with high levels of CARHSP1 had poorer survival when treated with radiotherapy. Collectively, our findings suggested that targeting the CARHSP1/TNF-α inflammatory signaling activation induced by radiotherapy might directly affect radioresistance and present an attractive therapeutic target for GBM, particularly for patients with high levels of CARHSP1.

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Arginine Decarboxylase Is Essential for Pneumococcal Stress Responses

Pathogens ◽

10.3390/pathogens10030286 ◽

2021 ◽

Vol 10 (3) ◽

pp. 286

Author(s):

Mary Frances Nakamya ◽

Moses B. Ayoola ◽

Leslie A. Shack ◽

Mirghani Mohamed ◽

Edwin Swiatlo ◽

...

Keyword(s):

Stress Responses ◽

Critical Role ◽

Acid Stress ◽

Arginine Decarboxylase ◽

Arginine Deiminase ◽

Dependent Manner ◽

Cellular Processes ◽

Opportunistic Human Pathogen ◽

Thiol Peroxidase ◽

The Impact

Polyamines such as putrescine, cadaverine, and spermidine are small cationic molecules that play significant roles in cellular processes, including bacterial stress responses and host–pathogen interactions. Streptococcus pneumoniae is an opportunistic human pathogen, which causes several diseases that account for significant morbidity and mortality worldwide. As it transits through different host niches, S. pneumoniae is exposed to and must adapt to different types of stress in the host microenvironment. We earlier reported that S. pneumoniae TIGR4, which harbors an isogenic deletion of an arginine decarboxylase (ΔspeA), an enzyme that catalyzes the synthesis of agmatine in the polyamine synthesis pathway, has a reduced capsule. Here, we report the impact of arginine decarboxylase deletion on pneumococcal stress responses. Our results show that ΔspeA is more susceptible to oxidative, nitrosative, and acid stress compared to the wild-type strain. Gene expression analysis by qRT-PCR indicates that thiol peroxidase, a scavenger of reactive oxygen species and aguA from the arginine deiminase system, could be important for peroxide stress responses in a polyamine-dependent manner. Our results also show that speA is essential for endogenous hydrogen peroxide and glutathione production in S. pneumoniae. Taken together, our findings demonstrate the critical role of arginine decarboxylase in pneumococcal stress responses that could impact adaptation and survival in the host.

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Colorectal Cancer Apoptosis Induced by Dietary δ-Valerobetaine Involves PINK1/Parkin Dependent-Mitophagy and SIRT3

International Journal of Molecular Sciences ◽

10.3390/ijms22158117 ◽

2021 ◽

Vol 22 (15) ◽

pp. 8117

Author(s):

Nunzia D’Onofrio ◽

Elisa Martino ◽

Luigi Mele ◽

Antonino Colloca ◽

Martina Maione ◽

...

Keyword(s):

Colorectal Cancer ◽

Colon Cancer ◽

Mitochondrial Dysfunction ◽

Cancer Cells ◽

Current Knowledge ◽

Apoptotic Cell ◽

Critical Role ◽

Dependent Manner ◽

Colon Cancer Cells ◽

Protein Levels

Understanding the mechanisms of colorectal cancer progression is crucial in the setting of strategies for its prevention. δ-Valerobetaine (δVB) is an emerging dietary metabolite showing cytotoxic activity in colon cancer cells via autophagy and apoptosis. Here, we aimed to deepen current knowledge on the mechanism of δVB-induced colon cancer cell death by investigating the apoptotic cascade in colorectal adenocarcinoma SW480 and SW620 cells and evaluating the molecular players of mitochondrial dysfunction. Results indicated that δVB reduced cell viability in a time-dependent manner, reaching IC50 after 72 h of incubation with δVB 1.5 mM, and caused a G2/M cell cycle arrest with upregulation of cyclin A and cyclin B protein levels. The increased apoptotic cell rate occurred via caspase-3 activation with a concomitant loss in mitochondrial membrane potential and SIRT3 downregulation. Functional studies indicated that δVB activated mitochondrial apoptosis through PINK1/Parkin pathways, as upregulation of PINK1, Parkin, and LC3B protein levels was observed (p < 0.0001). Together, these findings support a critical role of PINK1/Parkin-mediated mitophagy in mitochondrial dysfunction and apoptosis induced by δVB in SW480 and SW620 colon cancer cells.

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The binding of NCAM to FGFR1 induces a specific cellular response mediated by receptor trafficking

The Journal of Cell Biology ◽

10.1083/jcb.200903030 ◽

2009 ◽

Vol 187 (7) ◽

pp. 1101-1116 ◽

Cited By ~ 78

Author(s):

Chiara Francavilla ◽

Paola Cattaneo ◽

Vladimir Berezin ◽

Elisabeth Bock ◽

Diletta Ami ◽

...

Keyword(s):

Cell Migration ◽

Cellular Response ◽

Critical Role ◽

Biological Significance ◽

Receptor Activation ◽

Dependent Manner ◽

Fgf Receptor ◽

Neural Cell Adhesion ◽

Sustained Activation

Neural cell adhesion molecule (NCAM) associates with fibroblast growth factor (FGF) receptor-1 (FGFR1). However, the biological significance of this interaction remains largely elusive. In this study, we show that NCAM induces a specific, FGFR1-mediated cellular response that is remarkably different from that elicited by FGF-2. In contrast to FGF-induced degradation of endocytic FGFR1, NCAM promotes the stabilization of the receptor, which is recycled to the cell surface in a Rab11- and Src-dependent manner. In turn, FGFR1 recycling is required for NCAM-induced sustained activation of various effectors. Furthermore, NCAM, but not FGF-2, promotes cell migration, and this response depends on FGFR1 recycling and sustained Src activation. Our results implicate NCAM as a nonconventional ligand for FGFR1 that exerts a peculiar control on the intracellular trafficking of the receptor, resulting in a specific cellular response. Besides introducing a further level of complexity in the regulation of FGFR1 function, our findings highlight the link of FGFR recycling with sustained signaling and cell migration and the critical role of these events in dictating the cellular response evoked by receptor activation.

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