Fig. 4. Transgenic overexpression of Dnmt2 causes hypermethylation of the Drosophila genome. (A) Western analysis demonstrates significant levels of Dnmt2 protein in transgenic flies (left lanes). No protein was detectable in controls (right lane). (B) Genomic DNA from transgenic flies was analyzed by capillary electrophoresis. This revealed readily detectable amounts of 5-methylcytosine. (C) Very little 5-methylcytosine was present in matched control samples that did not overexpress Dnmt2. (D) The cytosine methylation level was quantified in several independent measurements from several independent experiments and the average was determined. Standard deviations are indicated by error bars.