Genome-wide detection of high abundance N6-methyladenosine sites by microarray.

N(6)-methyladenosine (m(6)A), the most abundant internal RNA modification, functions in diverse biological processes, including regulation of embryonic stem cell self-renewal and differentiation. As yet, methods to detect m(6)A in the transcriptome rely on the availability and quality of an m(6)A antibody and are often associated with a high rate of false positives. Here, based on our observation that m(6)A interferes with A-T/U pairing, we report a microarray-based technology to map m(6)A sites in mouse embryonic stem cells. We identified 72 unbiased sites exhibiting high m(6)A levels from 66 PolyA RNAs. Bioinformatics analyses suggest identified sites are enriched on developmental regulators and may in some contexts modulate microRNA/mRNA interactions. Overall, we have developed microarray-based technology to capture highly enriched m(6)A sites in the mammalian transcriptome. This method provides an alternative means to identify m(6)A sites for certain applications.