Reports

Dense nonsymmetrical DNA methylation resulting from repeat-induced point mutation in Neurospora

See allHide authors and affiliations

Science  10 Dec 1993:
Vol. 262, Issue 5140, pp. 1724-1728
DOI: 10.1126/science.8259516

Abstract

Cytosine methylation has been implicated in epigenetic control of gene expression in animals, plants, and fungi. It has been assumed that all methylation in eukaryotes is at symmetrical sequences such as CpG/GpC, because this can explain perpetuation of methylation states. Here the bisulfite genomic sequencing method was used to examine methylation in DNA from a Neurospora gene exposed to repeat-induced point mutation. 5-Methylcytosine was not limited to symmetrical sites and individual molecules showed different patterns and amounts of modification. The methylation extended beyond the mutated region and even beyond the edge of the duplicated segment.