Putative DNA-(amino)methyltransferases in eucaryotes

By computer analysis of the known data bases, we have established that the open reading frames (ORF) coding for proteins that possess high degree of h omology with procaryotic DNA-(amino)methyltransferases are present in the g enomes of Leishmania major, Saccharomyces cerevisiae, Schizosaccharomyces p ombe, Arabidopsis thaliana, Drosophila melanogaster, Caenorhabditis elegans , and Homo sapiens. Conservative motifs typical for bacterial DNA-(amino)me thyltransferases are detected in the amino acid sequences of these putative proteins. The ORF of all putative eucaryotic DNA-(amino)methyltransferases found are encoded in nuclear DNA. In mitochondrial genomes including a few fully sequenced higher plant mtDNA, nucleotide sequences significantly hom ologous to genes of procaryotic DNA-(amino)methyltransferases are not found . Thus, ORF homologous to bacterial adenine DNA- methyltransferases are pre sent in nuclei of protozoa, yeasts, insects, nematodes, vertebrates, higher plants, and other eucaryotes. A special search for corresponding proteins and, in particular, adenine DNA-methyltransferases in these organisms and a study of their functions are quite promising.