scholarly journals Campylobacter jejunitranscriptome changes during loss of culturability in water

2017 ◽  
Author(s):  
Christina Bronowski ◽  
Kasem Mustafa ◽  
Ian B. Goodhead ◽  
Chloe E. James ◽  
Charlotte Nelson ◽  
...  
Keyword(s):  
Gene Expression ◽  
Sampling Time ◽  
Natural Environments ◽  
Rapid Loss ◽  
Potential Reservoir ◽  
Different Temperatures ◽  
Bacterial Gastroenteritis ◽  
Flagellar Assembly ◽  
Different Strains ◽  
Considerable Loss

AbstractBackgroundThe natural environment serves as a potential reservoir forCampylobacter,the leading cause of bacterial gastroenteritis in humans. However, little is understood about the mechanisms underlying variations in survival characteristics between different strains ofC. jejuniin natural environments, including water.ResultsWe identified threeCampylobacter jejunistrains that exhibited variability in their ability to retain culturability after suspension in water at two different temperatures (4°C and 25°C). Of the three, strainsC. jejuniM1 exhibited the most rapid loss of culturability whilst retaining viability. Using RNAseq transcriptomics, we characterised C.jejuniM1 gene expression in response to suspension in water by analyzing bacterial suspensions recovered immediately after introduction into water (Time 0), and from two sampling time/temperature combinations where considerable loss of culturability was evident, namely (i) after 24 h at 25°C, and (ii) after 72 h at 4°C. Transcript data were compared with a culture-grown control. Some gene expression characteristics were shared amongst the three populations recovered from water, with more genes being up-regulated than down. Many of the up-regulated genes were identified in the Time 0 sample, whereas the majority of down-regulated genes occurred in the 25°C (24 h) sample.ConclusionsVariations in expression were found amongst genes associated with oxygen tolerance, starvation and osmotic stress. However, we also found upregulation of flagellar assembly genes, accompanied by down-regulation of genes involved in chemotaxis. Our data also suggested a switch from secretion via thesecsystem to via thetatsystem, and that the quorum sensing geneluxSmay be implicated in the survival of strain M1 in water. Variations in gene expression also occurred in accessory genome regions. Our data suggest that despite the loss of culturability,C. jejuniM1 remains viable and adapts via specific changes in gene expression.

scholarly journals Effect of Temperature during Drying and Storage of Dried Figs on Growth, Gene Expression and Aflatoxin Production

Toxins ◽  
2021 ◽  
Vol 13 (2) ◽  
pp. 134
Author(s):  
Ana Isabel Galván ◽  
Alicia Rodríguez ◽  
Alberto Martín ◽  
Manuel Joaquín Serradilla ◽  
Ana Martínez-Dorado ◽  
...  
Keyword(s):  
Gene Expression ◽  
Aflatoxin Production ◽  
Effect Of Temperature ◽  
Mycotoxin Production ◽  
Industrial Processing ◽  
Factors Associated ◽  
Different Temperatures ◽  
Major Producer ◽  
Main Factors ◽  
And Storage

Dried fig is susceptible to infection by Aspergillus flavus, the major producer of the carcinogenic mycotoxins. This fruit may be contaminated by the fungus throughout the entire chain production, especially during natural sun-drying, post-harvest, industrial processing, storage, and fruit retailing. Correct management of such critical stages is necessary to prevent mould growth and mycotoxin accumulation, with temperature being one of the main factors associated with these problems. The effect of different temperatures (5, 16, 25, 30, and 37 °C) related to dried-fig processing on growth, one of the regulatory genes of aflatoxin pathway (aflR) and mycotoxin production by A. flavus, was assessed. Firstly, growth and aflatoxin production of 11 A. flavus strains were checked before selecting two strains (M30 and M144) for in-depth studies. Findings showed that there were enormous differences in aflatoxin amounts and related-gene expression between the two selected strains. Based on the results, mild temperatures, and changes in temperature during drying and storage of dried figs should be avoided. Drying should be conducted at temperatures >30 °C and close to 37 °C, while industry processing, storage, and retailing of dried figs are advisable to perform at refrigeration temperatures (<10 °C) to avoid mycotoxin production.

scholarly journals Rapid loss of duplicate gene expression by natural selection

Heredity ◽  
1979 ◽  
Vol 43 (2) ◽  
pp. 247-258 ◽  
Author(s):  
Fred W Allendorf
Keyword(s):  
Gene Expression ◽  
Natural Selection ◽  
Duplicate Gene ◽  
Rapid Loss ◽  
Duplicate Gene Expression

scholarly journals Shade-Inducible Gene Expression Change in <i>Arabidopsis thaliana</i> at Different Temperatures

2016 ◽  
Vol 07 (02) ◽  
pp. 352-423
Author(s):  
ByungHoon B. Kim ◽  
Kaiesa L. Peets ◽  
Jamekia S. Grant ◽  
Joshua S. Hicks ◽  
Dominique C. Zellous ◽  
...  
Keyword(s):  
Gene Expression ◽  
Arabidopsis Thaliana ◽  
Gene Expression Change ◽  
Expression Change ◽  
Inducible Gene Expression ◽  
Different Temperatures ◽  
Inducible Gene

scholarly journals Dynamics of λ-cyhalothrin disappearance and expression of selected P450 genes in bees depending on the ambient temperature

2021 ◽  
Vol 19 (1) ◽  
pp. 1251-1258
Author(s):  
Bartosz Piechowicz ◽  
Marika Kobielska ◽  
Anna Koziorowska ◽  
Magdalena Podbielska ◽  
Ewa Szpyrka ◽  
...  
Keyword(s):  
Gene Expression ◽  
Ambient Temperature ◽  
Honey Bees ◽  
Half Life ◽  
Degradation Rate ◽  
Plant Protection ◽  
Plant Protection Product ◽  
Cytochrome P450 Genes ◽  
Qpcr Method ◽  
Different Temperatures

Abstract Temperature has a significant influence on the action of pyrethroids, and their effect increases with decreasing ambient temperature. Using gas chromatography, we assessed the degradation rate of λ-cyhalothrin, active ingredients (AI) of Karate Zeon 050 CS from pyrethroid group, in bees incubated for 48 h under different temperature conditions. With RT-qPCR method, we studied expression levels of selected cytochrome P450 genes after exposure to the plant protection product (PPP). The half-life of λ-cyhalothrin decreased from 43.32 to 17.33 h in the temperature range of 21–31°C. In animals incubated at 16°C, the AI half-life was even shorter and amounted to 10.19 h. The increase in temperature increased the expression of Cyp9Q1, Cyp9Q2, and Cyp9Q3 in the group of control bees. We showed a two-fold statistically significant increase in gene expression after treatment with PPP bees. The obtained results indicate that honey bees are characterized by susceptibility to pyrethroids that vary depending on the ambient temperature. This may be due to the different expressions of genes responsible for the detoxification of these PPPs at different temperatures.

Analysis of behavior using genetical genomics in mice as a model: from alcohol preferences to gene expression differences

Genome ◽  
2007 ◽  
Vol 50 (10) ◽  
pp. 877-897 ◽  
Author(s):  
Shiva M. Singh ◽  
Julie Treadwell ◽  
Morgan L. Kleiber ◽  
Michelle Harrison ◽  
Raihan K. Uddin
Keyword(s):  
Gene Expression ◽  
Rna Binding ◽  
Human Subjects ◽  
Fold Increase ◽  
Global Gene Expression ◽  
Genetic Dissection ◽  
Behavioral Phenotypes ◽  
Neurotransmitter Transport ◽  
Genetic Strains ◽  
Different Strains

Most familial behavioral phenotypes result from the complex interaction of multiple genes. Studies of such phenotypes involving human subjects are often inconclusive owing to complexity of causation and experimental limitations. Studies of animal models argue for the use of established genetic strains as a powerful tool for genetic dissection of behavioral disorders and have led to the identification of rare genes and genetic mechanisms implicated in such phenotypes. We have used microarrays to study global gene expression in adult brains of four genetic strains of mice (C57BL/6J, DBA/2J, A/J, and BALB/c). Our results demonstrate that different strains show expression differences for a number of genes in the brain, and that closely related strains have similar patterns of gene expression as compared with distantly related strains. In addition, among the 24 000 genes and ESTs on the microarray, 77 showed at least a 1.5-fold increase in the brains of C57BL/6J mice as compared with those of DBA/2J mice. These genes fall into such functional categories as gene regulation, metabolism, cell signaling, neurotransmitter transport, and DNA/RNA binding. The importance of these findings as a novel genetic resource and their use and application in the genetic analysis of complex behavioral phenotypes, susceptibilities, and responses to drugs and chemicals are discussed.

Abstract 268: Strain-specific Cardiac Fibroblast Response to Isoproterenol-induced Cardiac Fibrosis

2017 ◽  
Vol 121 (suppl_1) ◽  
Author(s):  
Shuin Park ◽  
Sara Ranjbarvaziri ◽  
Fides Lay ◽  
Peng Zhao ◽  
Aldons J Lusis ◽  
...  
Keyword(s):  
Gene Expression ◽  
Cardiac Fibrosis ◽  
Cardiac Fibroblasts ◽  
Expression Profiles ◽  
Inbred Mouse ◽  
Gene Expression Profiles ◽  
Mouse Strains ◽  
Sequencing Analysis ◽  
Different Strains

Fibroblasts are a heterogeneous population of cells that function within the injury response mechanisms across various tissues. Despite their importance in pathophysiology, the effects of different genetic backgrounds on fibroblast contribution to the development of disease has yet to be addressed. It has previously been shown that mice in the Hybrid Mouse Diversity Panel, which consists of 110 inbred mouse strains, display a spectrum in severity of cardiac fibrosis in response to chronic treatment of isoproterenol (ISO). Here, we characterized cardiac fibroblasts (CFbs) from three different mouse strains (C57BL/6J, C3H/HeJ, and KK/HIJ) which exhibited varying degrees of fibrosis after ISO treatment. The select strains of mice underwent sham or ISO treatment via intraperitoneally-implanted osmotic pumps for 21 days. Masson’s Trichrome staining showed significant differences in fibrosis in response to ISO, with KK/HIJ mice demonstrating the highest levels, C3H/HeJ exhibiting milder levels, and C57BL/6J demonstrating little to no fibrosis. When CFbs were isolated and cultured from each strain, the cells demonstrated similar traits at the basal level but responded to ISO stimuli in a strain-specific manner. Likewise, CFbs demonstrated differential behavior and gene expression in vivo in response to ISO. ISO treatment caused CFbs to proliferate similarly across all strains, however, immunofluorescence staining showed differential levels of CFb activation. Additionally, RNA-sequencing analysis revealed unique gene expression profiles of all three strains upon ISO treatment. Our study depicts the phenotypic heterogeneity of CFbs across different strains of mice and our results suggest that ISO-induced cardiac fibrosis is a complex process that is independent of fibroblast proliferation and is mainly driven by the activation/inhibition of genes involved in pro-fibrotic pathways.

scholarly journals Global Regulation of Gene Expression and Cell Differentiation in Caulobacter crescentus in Response to Nutrient Availability

2009 ◽  
Vol 192 (3) ◽  
pp. 819-833 ◽  
Author(s):  
Jennifer C. England ◽  
Barrett S. Perchuk ◽  
Michael T. Laub ◽  
James W. Gober
Keyword(s):  
Gene Expression ◽  
Nitrogen Limitation ◽  
Caulobacter Crescentus ◽  
Regulation Of Gene Expression ◽  
Fixed Time ◽  
Natural Environments ◽  
Swarmer Cell ◽  
Regulatory Strategies ◽  
Time Period ◽  
Regulated Gene Expression

ABSTRACT In a developmental strategy designed to efficiently exploit and colonize sparse oligotrophic environments, Caulobacter crescentus cells divide asymmetrically, yielding a motile swarmer cell and a sessile stalked cell. After a relatively fixed time period under typical culture conditions, the swarmer cell differentiates into a replicative stalked cell. Since differentiation into the stalked cell type is irreversible, it is likely that environmental factors such as the availability of essential nutrients would influence the timing of the decision to abandon motility and adopt a sessile lifestyle. We measured two different parameters in nutrient-limited chemostat cultures, biomass concentration and the ratio of nonstalked to stalked cells, over a range of flow rates and found that nitrogen limitation significantly extended the swarmer cell life span. The transcriptional profiling experiments described here generate the first comprehensive picture of the global regulatory strategies used by an oligotroph when confronted with an environment where key macronutrients are sparse. The pattern of regulated gene expression in nitrogen- and carbon-limited cells shares some features in common with most copiotrophic organisms, but critical differences suggest that Caulobacter, and perhaps other oligotrophs, have evolved regulatory strategies to deal distinctly with their natural environments. We hypothesize that nitrogen limitation extends the swarmer cell lifetime by delaying the onset of a sequence of differentiation events, which when initiated by the correct combination of external environmental cues, sets the swarmer cell on a path to differentiate into a stalked cell within a fixed time period.

Texture Changes during Uniaxial Compression of Mg-3Al-1Zn

2004 ◽  
Vol 467-470 ◽  
pp. 429-434 ◽  
Author(s):  
Petra Backx ◽  
Matthew R. Barnett ◽  
Leo Kestens
Keyword(s):  
Uniaxial Compression ◽  
Annealing Treatment ◽  
Processing Parameters ◽  
Mechanical Anisotropy ◽  
Uniaxial Compression Test ◽  
Compression Tests ◽  
Texture Change ◽  
Different Temperatures ◽  
Axis Compression ◽  
Different Strains

The mechanical anisotropy of wrought Mg alloys is very high. For example the yield stress of extruded Mg-3Al-1Zn tested in tension can be as high as twice that obtained in compression [1]. To solve the problems this creates for product design it is necessary to understand the sensitivity of texture to processing parameters. Uniaxial compression tests at different temperatures were performed on cylindrical samples of an extruded Mg-3Al-1Zn bar. The texture during this deformation changes from a situation where all crystal c-axes are nearly perpendicular to the sample axis to one where the c-axes are all nearly parallel to this axis. Compression was stopped at different strains to examine the rate of this texture change. Textures were examined using EBSD measurements. It was found that different mechanisms operate depending on the temperature of deformation and that a variety of textures can be created. Also it was seen that an annealing treatment performed after compression has an influence on the texture. Afterwards the samples were subjected to another uniaxial compression test to examine the influence of texture on room temperature properties.

Sign in / Sign up

Export Citation Format

Share Document