The Discovery And Identification Of WTAP,a Novel Component Of N~6-Methyladenosine Methyltransferase

N6-methyladnosine (m6A) is the most prevalent internal modification in polyadenylated mRNAs in higher eukaryotes, which could play important roles in post-transcriptional processes such as pre-mRNA splicing, transportation, degradation, translation and so on. The finding that m6A level changed during different stages of oncogenesis revealved the relationship between m6A and cancer. Furthermore, METTL3is reported to show diverse expression profiles in different embryo stages which indicated that m6A might be related to development. Until now, a lot of progresses have been made on the study of m6A, the formation of m6A is catalyzed by a huge methytransferase complex containing core functional component METTL3and the discovery of the m6A demethylases---FTO and ALKBH5makes m6A to be the first reversible RNA methylation. However the other components of the methyltransferase complex remain to be a mystery, so this study is designed to dissect the methyltransferase complex and explore the biological functions of METTL3. By successfully uncovering WTAP, the potential protein of METTL3via immunoprecipation, we proved the interaction between METTL3and WTAP on both protein and cellular levels. WTAP could co-localize with METTL3in the nuclear speckle which is an organell enriched in splcing factors. These findings are very important for the exploration on how m6A regulate biological processes such as target genes expression, alternative splicing and so on.