Epigenetics and Bacterial Infections

Institut Pasteur, Unité des Interactions Bactéries-Cellules, Paris F-75015, France.
Cold Spring Harbor Perspectives in Medicine (Impact Factor: 7.56). 12/2012; 2(12). DOI: 10.1101/cshperspect.a010272
Source: PubMed

ABSTRACT Epigenetic mechanisms regulate expression of the genome to generate various cell types during development or orchestrate cellular responses to external stimuli. Recent studies highlight that bacteria can affect the chromatin structure and transcriptional program of host cells by influencing diverse epigenetic factors (i.e., histone modifications, DNA methylation, chromatin-associated complexes, noncoding RNAs, and RNA splicing factors). In this article, we first review the molecular bases of the epigenetic language and then describe the current state of research regarding how bacteria can alter epigenetic marks and machineries. Bacterial-induced epigenetic deregulations may affect host cell function either to promote host defense or to allow pathogen persistence. Thus, pathogenic bacteria can be considered as potential epimutagens able to reshape the epigenome. Their effects might generate specific, long-lasting imprints on host cells, leading to a memory of infection that influences immunity and might be at the origin of unexplained diseases.

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Available from: Helene Bierne, May 11, 2014
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    • "As sequencing on this scale improves with longer, better quality reads we will be able to perform de novo assemblies for each genome, which would allow all DNA in an isolate to be identified and tested for association with a specific trait. It has been suggested that genome sequencing alone cannot give sufficient information to explain or predict complex phenotypes , as it does not consider the additional factors that affect protein expression such as epigenetics (Borrell and Gagneux 2011; Jelier et al. 2011; Beltrao et al. 2012; Bierne et al. 2012). However, here we have shown that using robust statistical techniques on large collections of sequenced isolates alongside machine learning approaches can yield desired results. "
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