Cytosine methylation changes in rice centromeric and telomeric sequences induced by foreign DNA introgression

Cytosine methylation changes (hyper- or hypomethylation) in centromeric and telomeric sequences were observed in all three studied rice introgression lines containing DNA from wild rice, Zizania latifolia Griseb. The changed genomic Southern hybridization patterns were complex and non-concordant bet ween a pair of isoschizomers (HpaII/MspI) digests, indicating methylation m odifications at both the inner and outer cytosines of the CCGG sites. The c hanged patterns were inherited through generations. Possible mechanism for the methylation changes and their potential implications for the phenotypic variation and genome organization are discussed.