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The N6-methyladenosine (m6A) modification is one of the most frequently methylated nucleotides in eukaryotic mRNA, accounting for over 80% of all RNA base methylations and present in various species.Recently two independent studies combining m6A-immunoprecipitation with high throughput analysis revealed that the m6A modification tends to mainly occur in intragenic regions including coding sequences (CDS), stop codon flanking regions and 3-UTR.The frequency was especially high in the 3-end of CDS and the first quarter of the 3-UTR, with an average of 1 m6A per 2000 ribonucleotides.The m6A modification occurs in highly conserved regions with the consensus sequence: RRACH (R=G or A; H=A, C or U).During the course of brain development a dynamic change in m6A levels on RNA can be observed, suggesting the existence of enzymes catalyzing its addition and the removal.Consistently we in collaboration with professor Chuan He identified two AlkB dioxygenase family proteins, FTO (Fat mass and obesity related gene) and ALKBH5, responsible for catalyzing the removal of the m6A mark both in vitro and in vivo.These two enzymes function in various biological processes ranging from development, metabolism, to fertility, and regulate the expression levels of thousands of genes, implying a pivotal physiological epitranscriptomic function of m6A in regulating RNA metabolism.We have also identified mammalian wilms tumour 1-associating protein (WTAP) and methyltransferase-like protein 14 (METTL14) as components of the mammalian METTL3 m6A methyltransferase complex.In particular, WTAP appears to serve as a regulatory subunit essential for METTL3 methyltrasferase activity.We will discuss this newly emerging research area in this genomics conference.