Dataset Information

MicroRNA buffering and altered variance of gene expression in response to Salmonella infection.

ABSTRACT: One potential role of miRNAs is to buffer variation in gene expression, although conflicting results have been reported. To investigate the buffering role of miRNAs in response to Salmonella infection in pigs, we sequenced miRNA and mRNA in whole blood from 15 pig samples before and after Salmonella challenge. By analyzing inter-individual variation in gene expression patterns, we found that for moderately and lowly expressed genes, putative miRNA targets showed significantly lower expression variance compared with non-miRNA-targets. Expression variance between highly expressed miRNA targets and non-miRNA-targets was not significantly different. Further, miRNA targets demonstrated significantly reduced variance after challenge whereas non-miRNA-targets did not. RNA binding proteins (RBPs) are significantly enriched among the miRNA targets with dramatically reduced variance of expression after Salmonella challenge. Moreover, we found evidence that targets of young (less-conserved) miRNAs showed lower expression variance compared with targets of old (evolutionarily conserved) miRNAs. These findings point to the importance of a buffering effect of miRNAs for relatively lowly expressed genes, and suggest that the reduced expression variation of RBPs may play an important role in response to Salmonella infection.

SUBMITTER: Bao H

PROVIDER: S-EPMC3981782 | biostudies-literature | 2014

REPOSITORIES: biostudies-literature

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MicroRNA buffering and altered variance of gene expression in response to Salmonella infection.

Bao Hua H Kommadath Arun A Plastow Graham S GS Tuggle Christopher K CK Guan Le Luo le L Stothard Paul P

PloS one 20140409 4

One potential role of miRNAs is to buffer variation in gene expression, although conflicting results have been reported. To investigate the buffering role of miRNAs in response to Salmonella infection in pigs, we sequenced miRNA and mRNA in whole blood from 15 pig samples before and after Salmonella challenge. By analyzing inter-individual variation in gene expression patterns, we found that for moderately and lowly expressed genes, putative miRNA targets showed significantly lower expression va ...[more]

PMID: 24718561

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Project description:Strong epidemiological and pathological evidence supports a role for Chlamydia pneumoniae infection in atherosclerosis and human coronary heart disease. Animal models have shown that C. pneumoniae disseminates hematogenously in infected monocytes and macrophages, while in vitro data suggest that infected macrophages can transmit C. pneumoniae infection directly to endothelial cells. Endothelial cells may be key in vivo targets for C. pneumoniae infection; given that these cells are important in regulating the dynamics of the vessel wall, we used cDNA microarrays to study the transcriptional response of endothelial cells to infection with C. pneumoniae. cDNA arrays were used to characterize the mRNA expression profiles for 268 human genes following infection with C. pneumoniae, which were compared to mRNA profiles of uninfected cells. Selected genes of interest were further investigated by reverse transcription-PCR throughout a 24-h period of infection. C. pneumoniae infection upregulated mRNA expression for approximately 20 (8%) of the genes studied. Genes coding for cytokines (interleukin-1), chemokines (monocyte chemotactic protein 1 and interleukin-8), and cellular growth factors (heparin-binding epidermal-like growth factor, basic fibroblast growth factor, and platelet-derived growth factor B chain) were the most prominently upregulated. In addition to these families of genes, increases in mRNA levels for intracellular kinases and cell surface receptors with signal transduction activities were observed. Time course experiments showed that mRNA levels were upregulated within 2 h following infection. These results expand our knowledge of the response of endothelial cells to C. pneumoniae by further defining the repertoire of C. pneumoniae-inducible genes and provide new insight into potential mechanisms of atherogenesis. In addition, the use of cDNA microarrays may prove useful for the study of host cell responses to C. pneumoniae infection during latent and replicative stages of infection and related pathology.

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MicroRNA buffering and altered variance of gene expression in response to Salmonella infection.

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MicroRNA buffering and altered variance of gene expression in response to Salmonella infection.

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