Analysis of overlapping cDNA clones specific for a putative second DNA methyltransferase-encoding gene in Arabidopsis...

We have isolated and sequenced overlapping cDNA clones specific for a putative second DNA methyltransferase (MTase)-encoding gene (MTase11) from Arabidopsis thaliana (At) recently described as a genomic DNA fragment [Scheidt et al., Nucleic Acids Res. 22 (1994) 953-958]. The gene seems to be present as a single copy in the At genome and is transcribed into a 2.2-kb messenger detectable only in young seedlings. Using sequence comparison we found structural differences between the cDNA clones and the previously reported genomic fragment. The amino-acid sequence deduced from the 1.8-kb cDNA sequence shows the occurrence of the conserved motif number VI characteristic for m5C-MTases. Northern and Southern analysis detects no cross-hybridization with the originally described MTase-encoding At gene (MTase1) [Finnegan and Dennis, Nucleic Acids Res. 21 (1993) 2383-2388].