Project description:Up until now, the existence of Dnmt2-mediated DNA methylation has mostly been supported by focal analyses in organisms that contain Dnmt2, but no Dnmt1 or Dnmt3 DNA methyltransferase. In these organisms, several independent studies have also provided support for a biologically important function of Dnmt2-dependent DNA methylation. For example, Dnmt2-dependent methylation in Entamoeba histolytica, the causative agent of amebic dysentery, has been connected to the parasite s virulence. However, global DNA methylation levels in Entamoeba have been found to be very low. In addition, no specific features, such as CpG-specificity and specificity for certain genetic subcompartments have been described. This distinguishes Dnmt2-dependent methylation patterns from all other known methylomes and has raised questions about the validity of the underlying results. We have used whole-genome bisulfite sequencing for an unbiased characterization of the Entamoeba histolytica methylome at single-base resolution in a E.histolytica strain HM-1:IMSS devoid of significant level of EhDnmt2 (Ehmeth) expression.
Project description:Up until now, the existence of Dnmt2-mediated DNA methylation has mostly been supported by focal analyses in organisms that contain Dnmt2, but no Dnmt1 or Dnmt3 DNA methyltransferase. In these organisms, several independent studies have also provided support for a biologically important function of Dnmt2-dependent DNA methylation. For example, Dnmt2-dependent methylation in Entamoeba histolytica, the causative agent of amebic dysentery, has been connected to the parasite s virulence. However, global DNA methylation levels in Entamoeba have been found to be very low. In addition, no specific features, such as CpG-specificity and specificity for certain genetic subcompartments have been described. This distinguishes Dnmt2-dependent methylation patterns from all other known methylomes and has raised questions about the validity of the underlying results. We have used whole-genome bisulfite sequencing for an unbiased characterization of the Entamoeba histolytica methylome at single-base resolution in a E.histolytica strain HM-1:IMSS devoid of significant level of EhDnmt2 (Ehmeth) expression. Paired-end BS-sequencing was performed on an Illumina Genome Analyzer with read lengths of 105 base pairs and an average insert size of 200 bp.
Project description:The ability of Entamoeba histolytica to phagocytose host cells correlates to observed virulence in vivo. To better understand the mechanism of phagocytosis we used paramagnetic beads coated with host ligand and sorted trophozoites based on phagocytic ability. Gene expression was then measured in both the sorted phagocytic and non-phagocytic populations using a custom Affymetrix chip for E. histolytica. Feed forward regulation of phagocytosis by Entamoeba histolytica. Infection and Immunity. PMID 23045476