An organ-specific hypomethylation of cotyledon genomic rDNA in Pisum sativum L

AbstractThe CCGG and GCGC sequences in pea genomic rDNA were found to be hypomethylated relative to the leaf in the developing cotyledon. No rRNA gene copies were detected with only unmethylated CCGG sequences and the majority appeared to contain a mixture of doubly methylated (mCmCGG) and partially methylated (CmGG) sites. Some CCGG sequences were shown to have a greater probability of being undermethylated. Seed development did not appear to act as a stimulus for de novo methylation