scholarly journals Transcriptional Response of Pasteurella multocida to Defined Iron Sources

2002 ◽  
Vol 184 (23) ◽  
pp. 6714-6720 ◽  
Author(s):  
Michael L. Paustian ◽  
Barbara J. May ◽  
Dongwei Cao ◽  
Daniel Boley ◽  
Vivek Kapur
Keyword(s):  
Gene Expression ◽  
Dna Microarrays ◽  
Pasteurella Multocida ◽  
Transcriptional Response ◽  
Global Gene Expression ◽  
Defined Medium ◽  
Ferric Citrate ◽  
Hypothetical Proteins ◽  
Chemically Defined Medium ◽  
Iron Source

ABSTRACT Pasteurella multocida was grown in iron-free chemically defined medium supplemented with hemoglobin, transferrin, ferritin, and ferric citrate as iron sources. Whole-genome DNA microarrays were used to monitor global gene expression over seven time points after the addition of the defined iron source to the medium. This resulted in a set of data containing over 338,000 gene expression observations. On average, 12% of P. multocida genes were differentially expressed under any single condition. A majority of these genes encoded P. multocida proteins that were involved in either transport and binding or were annotated as hypothetical proteins. Several trends are evident when the data from different iron sources are compared. In general, only two genes (ptsN and sapD) were expressed at elevated levels under all of the conditions tested. The results also show that genes with increased expression in the presence of hemoglobin did not respond to transferrin or ferritin as an iron source. Correspondingly, genes with increased expression in the transferrin and ferritin experiments were expressed at reduced levels when hemoglobin was supplied as the sole iron source. Finally, the data show that genes that were most responsive to the presence of ferric citrate did not follow a trend similar to that of the other iron sources, suggesting that different pathways respond to inorganic or organic sources of iron in P. multocida. Taken together, our results demonstrate that unique subsets of P. multocida genes are expressed in response to different iron sources and that many of these genes have yet to be functionally characterized.

Regulation of albumin gene expression in a series of rat hepatocyte cell lines immortalized by simian virus 40 and maintained in chemically defined medium

1987 ◽  
Vol 7 (10) ◽  
pp. 3740-3748
Author(s):  
C D Woodworth ◽  
H C Isom
Keyword(s):  
Gene Expression ◽  
Cell Lines ◽  
Simian Virus 40 ◽  
Growth Cycle ◽  
Defined Medium ◽  
Tyrosine Aminotransferase ◽  
Simian Virus ◽  
Chemically Defined Medium ◽  
Primary Hepatocytes ◽  
Albumin Production

A series of simian virus 40 (SV40)-immortalized hepatocyte cell lines were characterized for albumin production, the regulation of albumin production, and the expression of other liver-specific genes. This series of cell lines is particularly useful for studying the regulation of hepatocyte gene expression because the cell lines express liverlike levels of a number of liver-specific functions and do so while growing in a chemically defined medium. SV40-immortalized hepatocyte cell lines were derived from colonies of albumin-producing epithelial cells that arose after primary hepatocytes maintained in chemically defined medium were transfected with SV40 DNA. Some cell lines secreted albumin at levels equal to or greater than those secreted by freshly plated primary hepatocytes, and all but one line continued to produce albumin for more than 20 passages. The variation in albumin secretion among cell lines reflected differences in the amount of albumin produced per cell and not in the percentage of albumin-producing cells in each line. The characterization of selected cell lines showed that albumin production was regulated by cell density during the growth cycle. Albumin production in most cell lines was also regulated by dexamethasone; however, one cell line continued to produce high levels of albumin when the cells were grown in medium lacking dexamethasone, demonstrating that although glucocorticoid can induce albumin production in some cell lines, it is not required for high levels of albumin production by all cells in culture. Regulation of albumin production measured at the level of protein secretion was paralleled by changes in steady-state levels of a 2.3-kilobase albumin RNA. Albumin-producing SV40-immortalized hepatocytes secreted a variety of other plasma proteins, including transferrin, hemopexin, and the third component of complement. These cells also expressed tyrosine aminotransferase activity that was inducible by dexamethasone. Alpha-fetoprotein production was not detected in any of the cell lines examined.

scholarly journals C. elegans genetic background modifies the core transcriptional response in an α-synuclein model of Parkinson’s disease

2018 ◽  
Author(s):  
Yiru A. Wang ◽  
Basten L. Snoek ◽  
Mark G. Sterken ◽  
Joost A.G. Riksen ◽  
Jana J. Stastna ◽  
...  
Keyword(s):  
Gene Expression ◽  
Parkinson’S Disease ◽  
Parkinson's Disease ◽  
Genetic Background ◽  
Expression Patterns ◽  
Transcriptional Response ◽  
Global Gene Expression ◽  
C Elegans ◽  
The Core ◽  
Repair Mechanisms

AbstractAccumulation of protein aggregates is a major cause of Parkinson’s disease (PD), a progressive neurodegenerative condition that is one of the most common causes of dementia. Transgenic Caenorhabditis elegans worms expressing the human synaptic protein α-synuclein show inclusions of aggregated protein and replicate the defining pathological hallmarks of PD. It is however not known how PD progression and pathology differs among individual genetic backgrounds. Here, we compared gene expression patterns, and investigated the phenotypic consequences of transgenic α-synuclein expression in five different C. elegans genetic backgrounds. Transcriptome analysis indicates that the effects of -synuclein expression on pathways associated with nutrient storage, lipid transportation and ion exchange depend on the genetic background. The gene expression changes we observe suggest that a range of phenotypes will be affected by α-synuclein expression. We experimentally confirm this, showing that the transgenic lines generally show delayed development, reduced lifespan, and an increased rate of matricidal hatching. These phenotypic effects coincide with the core changes in gene expression, linking developmental arrest, mobility, metabolic and cellular repair mechanisms to α-synuclein expression. Together, our results show both genotype-specific effects and core alterations in global gene expression and in phenotype in response to -synuclein. We conclude that the PD effects are substantially modified by the genetic background, illustrating that genetic background mechanisms should be elucidated to understand individual variation in PD.

scholarly journals Induction of Mxi1-SRα by FOXO3a Contributes to Repression of Myc-Dependent Gene Expression

2007 ◽  
Vol 27 (13) ◽  
pp. 4917-4930 ◽  
Author(s):  
Oona Delpuech ◽  
Beatrice Griffiths ◽  
Philip East ◽  
Abdelkader Essafi ◽  
Eric W.-F. Lam ◽  
...  
Keyword(s):  
Gene Expression ◽  
Cell Cycle Progression ◽  
Dna Microarrays ◽  
Target Genes ◽  
Gene Activation ◽  
Transcriptional Response ◽  
Inhibitory Effect ◽  
Pi3 Kinase ◽  
Promoter Regions ◽  
Inhibition Of Proliferation

ABSTRACT Forkhead transcription factors of the O class (FOXOs) are important targets of the phosphatidylinositol 3-kinase (PI3-kinase)/Akt pathway. FOXOs have been implicated in the regulation of cell cycle progression, oxidative stress resistance, and apoptosis. Using DNA microarrays, we analyzed the transcriptional response to FOXO3a activation by gene expression analysis in DLD-1 colon cancer cells stably expressing a FOXO3a.A3-ER fusion protein. We found that activation of FOXO3a resulted in repression of a number of previously identified Myc target genes. Furthermore, FOXO3a activation induced expression of several members of the Mad/Mxd family of transcriptional repressors, most notably Mxi1. The induction of Mxi1 by FOXO3a was specific to the Mxi1-SRα isoform and was mediated by three highly conserved FOXO binding sites within the first intron of the gene. Activation of FOXO3a in response to inhibition of Akt also resulted in activation of Mxi1-SRα expression. Silencing of Mxi1 by small interfering RNA (siRNA) reduced FOXO3a-mediated repression of a number of Myc target genes. We also observed that FOXO3a activation induced a switch in promoter occupancy from Myc to Mxi1 on the E-box containing promoter regions of two Myc target genes, APEX and FOXM1. siRNA-mediated transient silencing of Mxi1 or all Mad/Mxd proteins reduced exit from S phase in response to FOXO3a activation, and stable silencing of Mxi1 or Mad1 reduced the growth inhibitory effect of FOXO3a. We conclude that induction of Mad/Mxd proteins contributes to the inhibition of proliferation in response to FOXO3a activation. Our results provide evidence of direct regulation of Mxi1 by FOXO3a and imply an additional mechanism through which the PI3-kinase/Akt/FOXO pathway can modulate Myc function.

A CHEMICALLY DEFINED MEDIUM FOR GROWTH OF PASTEURELLA MULTOCIDA

1966 ◽  
Vol 12 (5) ◽  
pp. 933-937 ◽  
Author(s):  
Laurence P. Watko
Keyword(s):  
Pasteurella Multocida ◽  
Defined Medium ◽  
Good Growth ◽  
Chemically Defined Medium ◽  
Biochemical Characteristics ◽  
Metallic Salts

The chemically defined medium of McKenzie et al. was modified by increasing dextrose and buffer and adding metallic salts. This modified medium supported growth of nine different isolates of P. multocida through 10 serial transfers. One isolate (strain X-73) was successfully subcultured through more than 100 transfers in the modified medium without change of its biochemical characteristics. Viable organisms were recovered from static cultures after 45 days" incubation at 37 C. A 1/10-ml inoculum containing approximately two or three organisms was sufficient to produce good growth within 24–48 h.

scholarly journals Global Gene Expression Profiling of Yersinia pestis Replicating inside Macrophages Reveals the Roles of a Putative Stress-Induced Operon in Regulating Type III Secretion and Intracellular Cell Division

2010 ◽  
Vol 78 (9) ◽  
pp. 3700-3715 ◽  
Author(s):  
Hana S. Fukuto ◽  
Anton Svetlanov ◽  
Lance E. Palmer ◽  
A. Wali Karzai ◽  
James B. Bliska
Keyword(s):  
Gene Expression ◽  
Yersinia Pestis ◽  
Type Iii Secretion ◽  
Dna Microarrays ◽  
Cell Envelope ◽  
Global Gene Expression ◽  
Reading Frame ◽  
Type Iii ◽  
Global Gene Expression Profiling ◽  
High Level

ABSTRACT Yersinia pestis, the causative agent of plague, is a facultative intracellular pathogen. Previous studies have indicated that the ability of Y. pestis to survive inside macrophages may be critical during the early stages of plague pathogenesis. To gain insights into the biology of intracellular Y. pestis and its environment following phagocytosis, we determined the genome-wide transcriptional profile of Y. pestis KIM5 replicating inside J774.1 macrophage-like cells using DNA microarrays. At 1.5, 4, and 8 h postinfection, a total of 801, 464, and 416 Y. pestis genes were differentially regulated, respectively, compared to the level of gene expression of control bacteria grown in tissue culture medium. A number of stress-response genes, including those involved in detoxification of reactive oxygen species, as well as several metabolic genes involved in macromolecule synthesis, were significantly induced in intracellular Y. pestis, consistent with the presence of oxidative stress and nutrient starvation inside Yersinia-containing vacuoles. A putative stress-induced operon consisting of y2313, y2315, and y2316 (y2313-y2316), and a previously unidentified open reading frame, orfX, was studied further on the basis of its high level of intracellular expression. Mutant strains harboring either deletion, Δy2313-y2316 or ΔorfX, exhibited diverse phenotypes, including reduced effector secretion by the type III secretion system, increased intracellular replication, and filamentous morphology of the bacteria growing inside macrophages. The results suggest a possible role for these genes in regulating cell envelope characteristics in the intracellular environment.

scholarly journals Effect of Anaerobiosis and Nitrate on Gene Expression in Pseudomonas aeruginosa

2005 ◽  
Vol 73 (6) ◽  
pp. 3764-3772 ◽  
Author(s):  
M. J. Filiatrault ◽  
V. E. Wagner ◽  
D. Bushnell ◽  
C. G. Haidaris ◽  
B. H. Iglewski ◽  
...  
Keyword(s):  
Gene Expression ◽  
Pseudomonas Aeruginosa ◽  
Differential Expression ◽  
Dna Microarrays ◽  
Transcriptional Response ◽  
Anaerobic Growth ◽  
Differentially Expressed

ABSTRACT DNA microarrays were used to examine the transcriptional response of Pseudomonas aeruginosa to anaerobiosis and nitrate. In response to anaerobic growth, 691 transcripts were differentially expressed. Comparisons of P. aeruginosa grown aerobically in the presence or the absence of nitrate showed differential expression of greater than 900 transcripts.

Global responses ofEscherichia colito adverse conditions determined by microarrays and FT-IR spectroscopy

2009 ◽  
Vol 55 (6) ◽  
pp. 714-728 ◽  
Author(s):  
Birgitte Moen ◽  
Astrid Oust Janbu ◽  
Solveig Langsrud ◽  
Øyvind Langsrud ◽  
Jon L. Hobman ◽  
...  
Keyword(s):  
Gene Expression ◽  
Ir Spectroscopy ◽  
Benzalkonium Chloride ◽  
Dna Microarrays ◽  
Unsaturated Fatty Acids ◽  
Heat Exposure ◽  
Global Gene Expression ◽  
Adverse Conditions ◽  
Ft Ir ◽  
Ft Ir Spectroscopy

The global gene expression and biomolecular composition in an Escherichia coli model strain exposed to 10 adverse conditions (sodium chloride, ethanol, glycerol, hydrochloric and acetic acid, sodium hydroxide, heat (46 °C), and cold (15 °C), as well as ethidium bromide and the disinfectant benzalkonium chloride) were determined using DNA microarrays and Fourier transform infrared (FT-IR) spectroscopy. In total, approximately 40% of all investigated genes (1682/4279 genes) significantly changed expression, compared with a nonstressed control. There were, however, only 3 genes (ygaW (unknown function), rmf (encoding a ribosomal modification factor), and ghrA (encoding a glyoxylate/hydroxypyruvate reductase)) that significantly changed expression under all conditions (not including benzalkonium chloride). The FT-IR analysis showed an increase in unsaturated fatty acids during ethanol and cold exposure, and a decrease during acid and heat exposure. Cold conditions induced changes in the carbohydrate composition of the cell, possibly related to the upregulation of outer membrane genes (glgAP and rcsA). Although some covariance was observed between the 2 data sets, principle component analysis and regression analyses revealed that the gene expression and the biomolecular responses are not well correlated in stressed populations of E. coli, underlining the importance of multiple strategies to begin to understand the effect on the whole cell.

Ozone-Induced Dysregulation of Neuroendocrine Axes Requires Adrenal-Derived Stress Hormones

2019 ◽  
Vol 172 (1) ◽  
pp. 38-50 ◽  
Author(s):  
Andres R Henriquez ◽  
John S House ◽  
Samantha J Snow ◽  
Colette N Miller ◽  
Mette C Schladweiler ◽  
...  
Keyword(s):  
Gene Expression ◽  
Hedgehog Signaling ◽  
Stress Hormones ◽  
Transcriptional Response ◽  
Global Gene Expression ◽  
Thyroid Stimulating Hormone ◽  
Ozone Exposure ◽  
Short Term ◽  
Sham Surgery ◽  
Wistar Kyoto

Abstract Acute ozone inhalation increases circulating stress hormones through activation of the sympathetic-adrenal-medullary and hypothalamic-pituitary-adrenal axes. Rats with adrenalectomy (AD) have attenuated ozone-induced lung responses. We hypothesized that ozone exposure will induce changes in circulating pituitary-derived hormones and global gene expression in the brainstem and hypothalamus, and that AD will ameliorate these effects. Male Wistar-Kyoto rats (13 weeks) that underwent sham surgery (SHAM) or AD were exposed to ozone (0.8 ppm) or filtered-air for 4 h. In SHAM rats, ozone exposure decreased circulating thyroid-stimulating hormone (TSH), prolactin (PRL), and luteinizing hormone (LH). AD prevented reductions in TSH and PRL, but not LH. AD increased adrenocorticotropic hormone approximately 5-fold in both air- and ozone-exposed rats. AD in air-exposed rats resulted in few significant transcriptional differences in the brainstem and hypothalamus (approximately 20 genes per tissue). In contrast, ozone-exposure in SHAM rats resulted in either increases or decreases in expression of hundreds of genes in the brainstem and hypothalamus relative to air-exposed SHAM rats (303 and 568 genes, respectively). Differentially expressed genes from ozone exposure were enriched for pathways involving hedgehog signaling, responses to alpha-interferon, hypoxia, and mTORC1, among others. Gene changes in both brain areas were analogous to those altered by corticosteroids and L-3,4-dihydroxyphenylalanine, suggesting a role for endogenous glucocorticoids and catecholamines. AD completely prevented this ozone-induced transcriptional response. These findings show that short-term ozone inhalation promotes a shift in brainstem and hypothalamic gene expression that is dependent upon the presence of circulating adrenal-derived stress hormones. This is likely to have profound downstream influence on systemic effects of ozone.

scholarly journals Expired Platelet Concentrate as a Source of Human Platelet Lysate for Xenogeneic-Free Culture of Human Dermal Fibroblasts

2021 ◽  
Vol 50 (8) ◽  
pp. 2355-2365
Author(s):  
Muhammad Najib Fathi Bin Hassan ◽  
Zheng Yie Yap ◽  
Yee Loong Tang ◽  
Min Hwei Ng ◽  
Jia Xian Law
Keyword(s):  
Gene Expression ◽  
Wound Healing ◽  
Human Platelet ◽  
Defined Medium ◽  
Pathogen Transmission ◽  
Dermal Fibroblasts ◽  
Platelet Lysate ◽  
Human Dermal Fibroblasts ◽  
Chemically Defined Medium ◽  
Human Platelet Lysate

Dermal fibroblasts have been used clinically to promote wound healing and to reduce wrinkles. Most of the time, fetal bovine serum (FBS) is used for the expansion of fibroblasts. In addition, chemically defined medium can also be used for fibroblast expansion. Nonetheless, both FBS and chemically defined medium are not ideal to culture cells that will be used clinically as FBS has the risk of pathogen transmission and induction of xenogeneic immune response whilst chemically defined medium is extremely expensive. In this study, we examine the potential of using human platelet lysate (hPL) prepared from expired platelet concentrates to culture human dermal fibroblasts. For the experiments, fibroblasts were cultured with 5 and 10% hPL, with 10% FBS as the control group to compare the cell morphology, viability, growth rate, extracellular matrix gene expression and wound healing. Results showed that fibroblasts cultured with hPL were more elongated and smaller in size. The cell viability was higher than 90% for all groups. Expansion with 10% hPL significantly shorten the population doubling time compared to the 5% hPL and 10% FBS groups. However, fibroblasts cultured with hPL have lower expression of type I collagen, type III collagen and fibronection as well as slower wound closure. In summary, hPL has the potential to be used as a serum substitute for FBS to expand fibroblasts as it significantly increases the cell proliferation. However, further studies are required to determine if the changes in the ECM gene expression and migration of the hPL-expanded fibroblasts will affect the efficacy of the cells in promoting in vivo wound healing.

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