Transcriptome-based mapping of m6A sites in newly synthesized mRNA population in U2OS cells.

The goal was to see whether and how mRNA stability is linked to m6A peak position in newly synthesized mRNA population. U2OS cells were metabolically labeled with bromouridine (BrU). Total cytoplasmic mRNA was extracted from labeled U2OS cells followed by BrU-RNA immunoprecipitation (BrU-RIP) to purify BrU-labeled mRNAs that represent a pool of newly synthesized mRNA. Four RNA samples were collected and fragmented to an average size of about 100nt, which was followed by m6A-RNA IP of m6A site-bearing RNA fragments.