Rickettsia rickettsii
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ABSTRACT:
PROVIDER: PRJNA382417 | ENA |
REPOSITORIES: ENA
Similar Datasets
Project description:Comparison of gene expression between the virulent Rickettsia rickettsii R strain and avirulent Rickettsia rickettsii Iowa. Keywords: virulent vs avirulent
2008-06-04 | GSE8041 | GEO
Project description:Comparison of gene expression between the virulent Rickettsia rickettsii R strain and avirulent Rickettsia rickettsii Iowa. Keywords: virulent vs avirulent Virulent Rickettsia rickettsii R strain in triplicate was compared to avirulent Rickettsia rickettsii Iowa in triplicate
2010-05-26 | E-GEOD-8041 | biostudies-arrayexpress
Project description:Rickettsiae are strict obligate intracellular pathogens that alternate between arthropod and mammalian hosts in a zoonotic cycle. Typically, pathogenic bacteria that cycle between environmental sources and mammalian hosts adapt to the respective environments by coordinately regulating gene expression such that genes essential for survival and virulence are expressed only upon infection of mammals. Temperature is a common environmental signal for upregulation of virulence gene expression although other factors may also play a role. We examined the transcriptional responses of Rickettsia rickettsii, the agent of Rocky Mountain spotted fever, to a variety of environmental signals expected to be encountered during its life cycle. R. rickettsii exposed to differences in growth temperature (25o C vs. 37o C), iron limitation, and host cell species displayed nominal changes in gene expression under any of these conditions with only 0, 5, or 7 genes, respectively, changing more than 3-fold in expression levels. R. rickettsii is not totally devoid of ability to respond to temperature shifts as cold shock (37o C vs. 4o C) induced a change greater than 3-fold in up to 57 genes. Rickettsiae continuously occupy a relatively stable environment which is the cytosol of eukaryotic cells. Because of their obligate intracellular character, rickettsiae are believed to be undergoing reductive evolution to a minimal genome. We propose that their relatively constant environmental niche has led to a minimal requirement for R. rickettsii to respond to environmental changes with a consequent deletion of non-essential transcriptional response regulators. A minimal number of transcriptional regulators in the R. rickettsii genome is consistent with this hypothesis.
2009-05-23 | GSE14965 | GEO
Project description:Genomic comparison of virulent Rickettsia rickettsii Sheila Smith and avirulent Rickettsia rickettsii Iowa
| PRJNA100859 | ENA
Project description:Rickettsia rickettsii transcriptome - Blood feeding response
| PRJNA189711 | ENA
Project description:Rickettsiae are strict obligate intracellular pathogens that alternate between arthropod and mammalian hosts in a zoonotic cycle. Typically, pathogenic bacteria that cycle between environmental sources and mammalian hosts adapt to the respective environments by coordinately regulating gene expression such that genes essential for survival and virulence are expressed only upon infection of mammals. Temperature is a common environmental signal for upregulation of virulence gene expression although other factors may also play a role. We examined the transcriptional responses of Rickettsia rickettsii, the agent of Rocky Mountain spotted fever, to a variety of environmental signals expected to be encountered during its life cycle. R. rickettsii exposed to differences in growth temperature (25o C vs. 37o C), iron limitation, and host cell species displayed nominal changes in gene expression under any of these conditions with only 0, 5, or 7 genes, respectively, changing more than 3-fold in expression levels. R. rickettsii is not totally devoid of ability to respond to temperature shifts as cold shock (37o C vs. 4o C) induced a change greater than 3-fold in up to 57 genes. Rickettsiae continuously occupy a relatively stable environment which is the cytosol of eukaryotic cells. Because of their obligate intracellular character, rickettsiae are believed to be undergoing reductive evolution to a minimal genome. We propose that their relatively constant environmental niche has led to a minimal requirement for R. rickettsii to respond to environmental changes with a consequent deletion of non-essential transcriptional response regulators. A minimal number of transcriptional regulators in the R. rickettsii genome is consistent with this hypothesis. various growth and environmental condition comparisons
2010-06-25 | E-GEOD-14965 | biostudies-arrayexpress
Project description:Rickettsia rickettsii transcriptome - Elevation of temperature response
| PRJNA189712 | ENA
Project description:One of the most important vectors of the Brazilian Spotted Fever, the tick Amblyomma aureolatum in Brazil was used in this study. We laboratorial controlled the infection of adult females of A. aureolatum with the virulent brazilian strain Taiacu of Rickettsia rickettsii. The group of ticks was divided into 2 testing groups, group 2 (G2) composed of adult females incubated at 35°C for 3 days that were not fed after molting to adults and group 3 (G3) composed of adult females fed on its favorite natural host, the dog (Canis familiaris) also for 3 days. Right after incubation or feeding, ticks were individually dissected and all internal organs were transferred to RNAlater® Solution (Life Technologies) until gDNA and total RNA simultaneously isolation. A total of 14 ticks of each group were analyzed in two biological replicates (7 ticks each). Dye-swap was also applied to construct the technical replicate of each biological sample
2013-12-01 | GSE44315 | GEO
Project description:Limited transcriptional responses of Rickettsia rickettsii exposed to environmental stimuli
| PRJNA111843 | ENA
Project description:One of the most important vectors of the Brazilian Spotted Fever, the tick Amblyomma aureolatum in Brazil was used in this study. We laboratorial controlled the infection of adult females of A. aureolatum with the virulent brazilian strain Taiacu of Rickettsia rickettsii. The group of ticks was divided into 2 testing groups, group 1 (G1) composed of adult females incubated at 25°C for 3 days and group 2 (G2) composed of adult females incubated at 35°C for 3 days. Right after incubation of both groups, ticks were individually dissected and all internal organs were transferred to RNAlater® Solution (Life Technologies) until gDNA and total RNA simultaneously isolation. A total of 14 ticks of each group were analyzed in two biological replicates (7 ticks each). Dye-swap was also applied to construct the technical replicate of each biological sample
2013-12-01 | GSE44316 | GEO