Sensing DNA methylation in the protozoan parasite Entamoeba histolytica.

In the protozoan parasite Entamoeba histolytica, 5-methylcytosine (m5C) was found predominantly in repetitive elements. Its formation is catalysed by Ehmeth, a DNA methyltransferase that belongs to the Dnmt2 subfamily. Here we describe a 32 kDa nuclear protein that binds in vitro with higher affinity to the methylated form of a DNA encoding a reverse transcriptase of an autonomous non-long-terminal repeat retrotransposon (RT LINE) compared with the non-methylated RT LINE.

Pleiotropic phenotype in Entamoeba histolytica overexpressing DNA methyltransferase (Ehmeth).

The protozoan parasite Entamoeba histolytica expresses a cytosine-5 DNA methyltransferase (Ehmeth) that belongs to the Dnmt2 proteins family. The biological function of members of the Dnmt2 family is unknown. Constitutive overexpression of Ehmeth resulted in a pleiotropic phenotype that includes accumulation of multinucleated cells, upregulation of Heat shock protein 70 (HSP70) expression and resistance to oxidative stress.

Entamoeba histolytica DNA methyltransferase (Ehmeth) is a nuclear matrix protein that binds EhMRS2, a DNA that includes a scaffold/matrix attachment region (S/MAR).

The protozoan parasite Entamoeba histolytica express a cytosine-5 DNA methyltransferase (Ehmeth) that belongs to the DNMT2 protein family. The biological function of members of this DNMT2 family is unknown. In the present study, we have demonstrated that Ehmeth is a nuclear matrix protein.

Identification of methylated sequences in genomic DNA of adult Drosophila melanogaster.

The genome of Drosophila melanogaster contains methylated cytosines. Recent studies indicate that DNA methylation in the fruit fly depends on one DNA methyltransferase, dDNMT2. No obvious phenotype is associated with the downregulation of this DNA methyltransferase.

Characterization of cytosine methylated regions and 5-cytosine DNA methyltransferase (Ehmeth) in the protozoan parasite Entamoeba histolytica.

The DNA methylation status of the protozoan parasite Entamoeba histolytica was heretofore unknown. In the present study, we developed a new technique, based on the affinity of methylated DNA to 5-methylcytosine antibodies, to identify methylated DNA in this parasite. Ribosomal DNA and ribosomal DNA circles were isolated by this method and we confirmed the validity of our approach by sodium bisulfite sequencing.