scholarly journals Generational Sensitivity Alteration in Chironomus Yoshimatsui to Carbamate and Pharmaceutical Chemicals and The Effect on Catalase, CYP450, and Hemoglobin Gene Transcription

2021 ◽  
Author(s):  
Makoto Ishimota ◽  
Naruto Tomiyama
Keyword(s):  
Treatment Group ◽  
Gene Transcription ◽  
Generalized Linear Model ◽  
Aquatic Organisms ◽  
Mrna Levels ◽  
Pharmaceutical Chemical ◽  
Hemoglobin Gene ◽  
Fifth Generation ◽  
Sensitivity Changes ◽  
Carbamate Pesticide

Abstract To ascertain the tolerance mechanisms of aquatic organisms to artificial chemicals, intergenerational sensitivity changes of Chironomus yoshimatsui to a carbamate pesticide (pirimicarb) and pharmaceutical chemical (diazepam) were investigated. The larvae (< 48-h-old) in each generation were exposed to both chemicals for 48 h and then the surviving chironomids were cultured until the fifth generation (F0–F4) without chemical addition. The 48-h 50% effective concentration (EC50) value of chironomids was determined for each generation. In the pirimicarb treatment group, the EC50 values significantly increased in F3 and F4, and those in the diazepam treatment group slightly increased. Catalase, Cytochrome P450 and hemoglobin (Hb) mRNA levels were monitored to see whether these were related to the trans-generational sensitivity. Although the generalized linear model results showed that the sensitivity to diazepam was slightly increased in the diazepam treatment, we could not find any mRNA levels related to sensitivity alteration. In contrast, the model approach showed that the chironomids exposed to pirimicarb trans-generationally became tolerant with increasing Hb mRNA levels. Therefore, they might decrease their oxidative chemical stress by modifying Hb gene transcription.

Nitric oxide increases IL-8 gene transcription and mRNA stability to enhance IL-8 gene expression in lung epithelial cells

2004 ◽  
Vol 287 (4) ◽  
pp. L764-L773 ◽  
Author(s):  
Loretta Sparkman ◽  
Vijayakumar Boggaram
Keyword(s):  
Gene Expression ◽  
Nitric Oxide ◽  
Protein Kinase ◽  
Epithelial Cells ◽  
Gene Transcription ◽  
Mrna Stability ◽  
Inflammatory Responses ◽  
Lung Epithelial Cells ◽  
Mrna Levels ◽  
Lung Epithelial

Interleukin (IL)-8, a C-X-C chemokine, is a potent chemoattractant and an activator for neutrophils, T cells, and other immune cells. The airway and respiratory epithelia play important roles in the initiation and modulation of inflammatory responses via production of cytokines and surfactant. The association between elevated levels of nitric oxide (NO) and IL-8 in acute lung injury associated with sepsis, acute respiratory distress syndrome, respiratory syncytial virus infection in infants, and other inflammatory diseases suggested that NO may play important roles in the control of IL-8 gene expression in the lung. We investigated the role of NO in the control of IL-8 gene expression in H441 lung epithelial cells. We found that a variety of NO donors significantly induced IL-8 mRNA levels, and the increase in IL-8 mRNA was associated with an increase in IL-8 protein. NO induction of IL-8 mRNA was due to increases in IL-8 gene transcription and mRNA stability. NO induction of IL-8 mRNA levels was not inhibited by 1H-[1,2,4]oxadiazolo[4,3-a]quinoxalin-1-one and KT-5823, inhibitors of soluble guanylate cyclase and protein kinase G, respectively, and 8-bromo-cGMP did not increase IL-8 mRNA levels. This indicated that NO induces IL-8 mRNA levels independently of changes in the intracellular cGMP levels. NO induction of IL-8 mRNA was significantly reduced by inhibitors of extracellular regulated kinase and protein kinase C. IL-8 induction by NO was also reduced by hydroxyl radical scavengers such as dimethyl sulfoxide and dimethylthiourea, indicating the involvement of hydroxyl radicals in the induction process. NO induction of IL-8 gene expression could be a significant contributing factor in the initiation and induction of inflammatory response in the respiratory epithelium.

The Corfu δβ thalassemia deletion disrupts γ-globin gene silencing and reveals post-transcriptional regulation of HbF expression

Blood ◽  
2005 ◽  
Vol 105 (5) ◽  
pp. 2154-2160 ◽  
Author(s):  
Lyubomira Chakalova ◽  
Cameron S. Osborne ◽  
Yan-Feng Dai ◽  
Beatriz Goyenechea ◽  
Anna Metaxotou-Mavromati ◽  
...  
Keyword(s):  
Transcriptional Regulation ◽  
Gene Transcription ◽  
Globin Gene ◽  
Fetal Hemoglobin ◽  
Critical Threshold ◽  
Critical Element ◽  
Mrna Levels ◽  
Globin Genes ◽  
Mrna Accumulation ◽  
Post Transcriptional Regulation

Abstract The 7.2 kilobase (kb) Corfu δβ thalassemia mutation is the smallest known deletion encompassing a region upstream of the human δ gene that has been suggested to account for the vastly different phenotypes in hereditary persistence of fetal hemoglobin (HPFH) versus β thalassemia. Fetal hemoglobin (HbF) expression in Corfu heterozygotes and homozygotes is paradoxically dissimilar, suggesting conflicting theories as to the function of the region on globin gene regulation. Here, we measure γ- and β-globin gene transcription, steady-state mRNA, and hemoglobin expression levels in primary erythroid cells cultured from several patients with Corfu δβ thalassemia. We show through RNA fluorescence in situ hybridization that the Corfu deletion results in high-level transcription of the fetal γ genes in cis with a concomitant reduction in transcription of the downstream β gene. Surprisingly, we find that elevated γ gene transcription does not always result in a corresponding accumulation of γ mRNA or fetal hemoglobin, indicating a post-transcriptional regulation of γ gene expression. The data suggest that efficient γ mRNA accumulation and HbF expression are blocked until β mRNA levels fall below a critical threshold. These results explain the Corfu paradox and show that the deleted region harbors a critical element that functions in the developmentally regulated transcription of the β-globin genes.

scholarly journals Feedback Inhibition of Human Scavenger Receptor Class B Type I Gene Expression by Glucocorticoid in Adrenal and Ovarian Cells

Endocrinology ◽  
2010 ◽  
Vol 151 (7) ◽  
pp. 3214-3224 ◽  
Author(s):  
Sofia Mavridou ◽  
Maria Venihaki ◽  
Olga Rassouli ◽  
Christos Tsatsanis ◽  
Dimitris Kardassis
Keyword(s):  
Gene Expression ◽  
Gene Transcription ◽  
Feedback Inhibition ◽  
Steroid Hormone ◽  
Scavenger Receptor ◽  
Type I ◽  
Mrna Levels ◽  
Ovarian Cells ◽  
Scavenger Receptor Class ◽  
Class B

Scavenger receptor class B type I (SR-BI) facilitates the reverse transport of excess cholesterol from peripheral tissues to the liver via high-density lipoproteins. In steroidogenic tissues, SR-BI supplies cholesterol for steroid hormone production. We show here that the transcription of the human SR-BI gene is subject to feedback inhibition by glucocorticoid in adrenal and ovarian cells. SR-BI mRNA levels were increased in adrenals from corticosterone-insufficient Crh−/− mice, whereas corticosterone replacement by oral administration inhibited SR-BI gene expression in these mice. SR-BI mRNA levels were increased in adrenals from wild-type mice treated with metyrapone, a drug that blocks corticosterone synthesis. Experiments in adrenocortical H295R and ovarian SKOV-3 cells using cycloheximide and siRNA-mediated gene silencing revealed that glucocorticoid-mediated inhibition of SR-BI gene transcription requires de novo protein synthesis and the glucocorticoid receptor (GR). No direct binding of GR to the SR-BI promoter could be demonstrated in vitro and in vivo, suggesting an indirect mechanism of repression of SR-BI gene transcription by GR in adrenal cells. Deletion analysis established that the region of the human SR-BI promoter between nucleotides −201 and −62 is sufficient to mediate repression by glucocorticoid. This region contains putative binding sites for transcriptional repressors that could play a role in SR-BI gene regulation in response to glucocorticoid. In summary, this is the first report showing that glucocorticoid suppress SR-BI expression suggesting that steroidogenic tissues maintain steroid hormone homeostasis by prohibiting SR-BI-mediated high-density lipoprotein cholesterol uptake when the endogenous levels of glucocorticoid are elevated.

Role of glucocorticoids in activation of hepatic PEPCK gene transcription during exercise

1994 ◽  
Vol 266 (4) ◽  
pp. E560-E566 ◽  
Author(s):  
J. E. Friedman
Keyword(s):  
Transgenic Mice ◽  
Gene Transcription ◽  
Phosphoenolpyruvate Carboxykinase ◽  
Mrna Levels ◽  
Camp Response Element ◽  
Carbohydrate Diet ◽  
High Carbohydrate ◽  
Enhancer Binding Protein ◽  
Response To Exercise

The objective of these studies was to determine the molecular basis for the activation of phosphoenolpyruvate carboxykinase (PEPCK) gene transcription during prolonged submaximal exercise. Mice were fed a high-carbohydrate diet for 1 wk and exercised continuously by swimming for up to 120 min. The level of hepatic PEPCK mRNA increased progressively during exercise, reaching 510% above control, whereas transcription of the PEPCK gene increased 1,000%, before decreasing to control levels within 60 min of recovery. In transgenic mice carrying a chimeric gene consisting of the PEPCK promoter linked to a reporter gene for bovine growth hormone (bGH), PEPCK(-460)-bGH, the level of hepatic bGH mRNA increased by 490% in response to exercise, similar to the increase in the expression of the native PEPCK gene. However, in transgenic mice with a deletion of the glucocorticoid regulatory unit, PEPCK(-355)-bGH, bGH mRNA did not increase above control values. In transgenic mice with a block mutation in adenosine 3',5'-cyclic monophosphate (cAMP) regulatory regions -90/-82 and -250/-234, PEPCK cAMP response element 1 (CRE-1)/P3(1)-bGH, exercise increased bGH mRNA 260% above controls. Adrenalectomy (Adx) had no effect on PEPCK mRNA levels in nonexercised mice, whereas in adrenalectomized (Adx)-exercised mice, PEPCK mRNA increased only 80% above basal, and, in Adx mice injected with dexamethasone, PEPCK mRNA increased with exercise 570% above controls. Exercise was also associated with a large increase in transcription of the gene for the transcription factor CCAAT/enhancer-binding protein beta (C/EBP-beta) and a smaller rise in transcription of c-jun gene, both of which returned to control levels during recovery.(ABSTRACT TRUNCATED AT 250 WORDS)

scholarly journals Regulation of glucose transporters GLUT-4 and GLUT-1 gene transcription in denervated skeletal muscle

1998 ◽  
Vol 84 (5) ◽  
pp. 1661-1666 ◽  
Author(s):  
Jared P. Jones ◽  
Edward B. Tapscott ◽  
Ann Louise Olson ◽  
Jeffrey E. Pessin ◽  
G. Lynis Dohm
Keyword(s):  
Skeletal Muscle ◽  
Gene Transcription ◽  
Male Rats ◽  
Mrna Levels ◽  
Rnase Protection ◽  
Glut 1 ◽  
Glut 4 ◽  
The Right ◽  
Gastrocnemius Muscles ◽  
Cat Gene

Because GLUT-4 expression is decreased whereas GLUT-1 expression is increased in denervated skeletal muscle, we examined the effects of denervation on GLUT-4 and GLUT-1 gene transcription. The right hindlimb skeletal muscle of male transgenic mice containing sequential truncations (2,400, 1,639, 1,154, and 730 bp) of the human GLUT-4 promoter linked to the chloramphenacol acyl transferase (CAT) gene was denervated, and the contralateral hindlimb was sham operated. RNase protection analysis revealed that after 72 h denervation decreased CAT mRNA and GLUT-4 mRNA levels 64–85%, respectively ( P < 0.05), in the gastrocnemius muscles. In contrast, denervation of the right hindlimb of male rats increased GLUT-1 gene transcription and GLUT-1 mRNA levels by 94 and 213%, respectively ( P < 0.05). In conclusion, GLUT-4 transcription is decreased but GLUT-1 transcription is increased in denervated skeletal muscle, suggesting that the effects of denervation on GLUT-4 and GLUT-1 expression are, in part, transcriptionally mediated. Furthermore, these data indicate that a DNA sequence regulated by denervation is located within 730 bp of the 5′-flanking promoter region of the human GLUT-4 gene.

Physiological concentrations of insulin and T3 stimulate 3T3-L1 adipocyte acyl-CoA synthetase gene transcription

1996 ◽  
Vol 270 (5) ◽  
pp. E873-E881 ◽  
Author(s):  
M. S. Kansara ◽  
A. K. Mehra ◽  
J. Von Hagen ◽  
E. Kabotyansky ◽  
P. J. Smith
Keyword(s):  
Gene Transcription ◽  
Fold Increase ◽  
Mrna Levels ◽  
Dependent Manner ◽  
Long Chain Fatty Acids ◽  
Reciprocal Regulation ◽  
Stearoyl Coa Desaturase ◽  
Dose Dependent ◽  
Long Chain ◽  
Stimulation Of

Acyl-CoAsynthetase (ACS) is a key gene for cellular utilization of long-chain fatty acids. We characterized its regulation by physiological concentrations of insulin that acutely regulate metabolism. Our results demonstrate that subnanomolar insulin rapidly and maximally stimulates ACS gene transcription in the absence of protein synthesis; 0.5 nM insulin produced a 2.3 +/- 0.1-fold increase in ACS mRNA levels and induced ACS gene transcription 2.4 +/- 0.3-fold. The insulin sensitivity of ACS was compared with lipoprotein lipase (LPL) and stearoyl-CoA desaturase-1 (SCD-1), which were both less sensitive to insulin. Physiological triiodothyronine (10 nm) also induced ACS mRNA 2.4 +/- 0.1-fold and gene transcription 2.8 +/- 0.3-fold and coordinately induced LPL and SCD-1 mRNA and gene transcription. Because insulin and adenosine 3',5'-cyclic monophosphate often regulate genes involved in lipid and carbohydrate metabolism in a reciprocal manner, we evaluated effects of 1-methyl-3-isobutylxanthine (MIX).ACS mRNA levels were strongly downregulated by MIX in a dose-dependent manner, and ACS gene transcription inhibited in a coordinate manner with LPL and SCD-1. These data demonstrate a uniquely sensitive pattern of stimulation of ACS gene transcription by insulin with reciprocal regulation by MIX, and they suggest a significant role for ACS as a tightly regulated “gatekeeper” gene participating in the control of adipocyte metabolism.

Hypoxia downregulates tropoelastin gene expression in rat lung fibroblasts by pretranslational mechanisms

1999 ◽  
Vol 277 (3) ◽  
pp. L566-L572 ◽  
Author(s):  
John L. Berk ◽  
Nima Massoomi ◽  
Christine Hatch ◽  
Ronald H. Goldstein
Keyword(s):  
Gene Expression ◽  
Gene Transcription ◽  
Actinomycin D ◽  
Lung Fibroblasts ◽  
Mrna Levels ◽  
Rat Lung ◽  
Cell Toxicity ◽  
Chromium Release ◽  
Injured Lung ◽  
Isolated Rat Lung

Elastolytic lung injury disrupts cell barriers, flooding alveoli and producing regional hypoxia. Abnormal O2 tensions may alter repair of damaged elastin fibers. To determine the effect of hypoxia on extravascular elastin formation, we isolated rat lung fibroblasts and cultured them under a variety of O2 conditions. Hypoxia downregulated tropoelastin mRNA in a dose- and time-related fashion while upregulating glyceraldehyde-3-phosphate dehydrogenase mRNA levels. The changes in tropoelastin gene expression were not due to cell toxicity as measured by chromium release and cell proliferation studies. Neither cycloheximide nor actinomycin D abrogated this effect. Hypoxia induced early decreases in tropoelastin mRNA stability; minor suppression of gene transcription occurred later. When returned to 21% O2, tropoelastin mRNA recovered to control levels in part by upregulating tropoelastin gene transcription. Taken together, these data indicate that hypoxia regulates tropoelastin gene expression and may alter repair of acutely injured lung.

scholarly journals Transcriptional and posttranscriptional modulation of human neutrophil elastase gene expression

Blood ◽  
1992 ◽  
Vol 79 (10) ◽  
pp. 2733-2740 ◽  
Author(s):  
K Yoshimura ◽  
RG Crystal
Keyword(s):  
Gene Expression ◽  
Bone Marrow ◽  
Gene Transcription ◽  
Neutrophil Elastase ◽  
Human Neutrophil ◽  
Leukemia Cell Line ◽  
Human Neutrophil Elastase ◽  
Mrna Levels ◽  
Mrna Transcript ◽  
Lineage Differentiation

Abstract Human neutrophil elastase (NE), a 29-Kd potent serine protease stored in azurophilic granules of mature neutrophils, is coded for by the NE gene, a single copy gene with 5 exons spanning a 6-kb segment of chromosome 11 at q14. With the knowledge that the NE gene expression is limited to early myeloid cell differentiation, mechanisms modulating expression of the NE gene were evaluated in the HL-60 promyelocytic leukemia cell line, a model of early bone marrow precursor cells. Consistent with the presence of NE messenger RNA (mRNA) transcripts in undifferentiated HL-60 cells, nuclear transcription run-on analyses showed that HL-60 cells actively transcribed the NE gene. However, the transcription rate of the NE gene was relatively low, only 40% of the myeloperoxidase gene, a gene expressed in parallel with NE. When induced toward the mononuclear phagocytic lineage with phorbol 12- myristate 13-acetate (PMA), HL-60 cells exhibited marked suppression of NE gene transcription, declining to 17% of the resting rate within 2 days. Induction toward mononuclear phagocytic lineage differentiation caused no change in NE mRNA transcript half-life (T1/2), but mRNA levels decreased markedly over time, with levels undetectable 1.5 days after PMA stimulation. In contrast, when induced toward the myelocytic lineage with dimethyl sulfoxide, the rate of NE gene transcription increased 1.9-fold within 5 days. Interestingly, the mRNA transcript levels increased 2.5-fold by 5 days despite the fact that induction toward myelocytic lineage differentiation was accompanied by a marked reduction of NE mRNA transcript T1/2. Together, these observations suggest that the NE gene expression during bone marrow differentiation is modulated mainly at the transcriptional level, with some posttranscriptional modulation contributing, particularly during myelocytic lineage differentiation.

scholarly journals Mechanisms regulating the mRNA levels of interleukin-5 and two other coordinately expressed lymphokines in the murine T lymphoma EL4.23

Blood ◽  
1994 ◽  
Vol 83 (12) ◽  
pp. 3620-3628 ◽  
Author(s):  
H Naora ◽  
IG Young
Keyword(s):  
Gene Transcription ◽  
De Novo ◽  
Mrna Levels ◽  
Interleukin 5 ◽  
Mrna Stabilization ◽  
Gm Csf ◽  
Mrna Induction ◽  
Run Off ◽  
T Lymphoma ◽  
Macrophage Colony

Abstract The mechanisms that regulate the mRNA levels of interleukin-5 (IL-5) were compared with those regulating the mRNA levels of two other coordinately expressed lymphokines in the murine T lymphoma EL4.23. Our results indicate that IL-5 mRNA levels are independently regulated from those of IL-2 and granulocyte-macrophage colony-stimulating factor (GM- CSF) mRNAs. The induction of IL-5 mRNA by phorbol 12-myristate 13- acetate (PMA) stimulation was found to be cyclosporin A-resistant, in contrast to the induction of IL-2 and GM-CSF mRNAs. Although the three lymphokine mRNAs were not detected in unstimulated cells by Northern blot analysis, the GM-CSF gene was found by nuclear run-off analysis to be constitutively transcribed. However, the IL-2 and IL-5 genes were transcriptionally inactive in the absence of PMA stimulation. The induction of IL-5 mRNA by PMA stimulation primarily involved increased transcriptional activity. In contrast, GM-CSF mRNA induction predominantly involved enhanced mRNA stability. Both transcriptional and mRNA stabilization mechanisms appeared to regulate IL-2 mRNA induction. The activation of IL-2 and IL-5 gene transcription was dependent on de novo protein synthesis. Cellular treatment with cycloheximide enhanced IL-2 gene transcription once activation was initiated, implicating the involvement of a labile repressor(s). Furthermore, IL-5 mRNA was more stable than IL-2 and GM-CSF mRNAs. These latter two species were stabilized by cycloheximide, suggesting that a labile mechanism may regulate their degradation.

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