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O'Doherty, A. M.

Publications and source records attributed to O'Doherty, A. M..

2 recordsLinked to original sources

Alveolar macrophage chromatin is uniquely modified to orchestrate host response to Mycobacterium bovis infection

Mycobacterium bovis, the causative pathogen of bovine tuberculosis (bTB), induces extensive reprogramming of the macrophage transcriptome during infection. To identify key transcriptional changes in infected bovine alveolar macrophages (bAM), we have performed both gene expression (RNA-seq) and epigenomic (ChIP-seq) analyses using two key histone modification marks associated with activation (H3K4me3) and repression (H3K27me3). Together with RNA polymerase II (PolII) occupancy data, we show that reprogramming of the bAM transcriptome after M. bovis infection affects key immune response genes. Identification of these genes also facilitated integration of GWAS data, which identified genomic regions and SNPs significantly associated with resilience to infection with M. bovis in cattle.\n\nHighlightsO_LIComprehensive analysis of bovine alveolar macrophage (bAM) transcriptome and chromatin architecture revealed Mycobacterium bovis (M. bovis) induces genome-wide chromatin remodelling in bAM\nC_LIO_LIM. bovis induces transcriptional changes of immune response genes, associated with changes of histone modifications and RNA Polymerase II (PolII) occupancy\nC_LIO_LIGWAS integration of our ChIP study enabled the identification of important SNPs for bovine tuberculosis (bTB) susceptibility\nC_LI\n\nGraphical Abstract\n\nO_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=69 SRC=\"FIGDIR/small/520098_ufig1.gif\" ALT=\"Figure 1\">\nView larger version (19K):\norg.highwire.dtl.DTLVardef@1946689org.highwire.dtl.DTLVardef@1d7c0aborg.highwire.dtl.DTLVardef@1aa5c1forg.highwire.dtl.DTLVardef@1860ea5_HPS_FORMAT_FIGEXP M_FIG C_FIG

genomics↗

The bovine alveolar macrophage DNA methylome is resilient to infection with Mycobacterium bovis

DNA methylation is pivotal in orchestrating gene expression patterns in various mammalian biological processes. Perturbation of the bovine alveolar macrophage (bAM) transcriptome, due to Mycobacterium bovis (M. bovis) infection, has been well documented; however, the impact of this intracellular pathogen on the bAM epigenome has not been determined. Here, whole genome bisulfite sequencing (WGBS) was used to assess the effect of M. bovis infection on the bAM DNA methylome. The methylomes of bAM infected with M. bovis were compared to those of non-infected bAM 24 hours post-infection (hpi). No differences in DNA methylation (CpG or non-CpG) were observed. Analysis of DNA methylation at proximal promoter regions uncovered >250 genes harbouring intermediately methylated (IM) promoters (average methylation of 33-66%). Gene ontology analysis, focusing on genes with low, intermediate or highly methylated promoters, revealed that genes with IM promoters were enriched for immune-related GO categories; this enrichment was not observed for genes in the high or low methylation groups. Targeted analysis of genes in the IM category confirmed the WGBS observation. This study is the first in cattle examining genome-wide DNA methylation at single nucleotide resolution in an important bovine cellular host-pathogen interaction model, providing evidence for IM promoter methylation in bAM.

genomics↗