3T3-L1 pre-adipocytes were obtained from ATCC (Manassas, VA). The human FTO and mouse RUNX1T1 genes were cloned into pEGFP-C1B56 (link). Human SR plasmids were bought from OriGene Technologies (Rockville, MD). The expression constructs were generated using PCR and subcloned into pCS2+ vectors with an N-terminal FLAG tag57 (link). Polyclonal rabbit anti-FTO antibody was affinity-purified from rabbits immunized with 6×His-tagged full-length human FTO protein as previously reported9 (link). Polyclonal rabbit anti-ALKBH5 antibody was generated against synthesized peptide (RKYQEDSDERSD, 58-70 amino acids of human ALKBH5) by CWBio (Beijing) as previously reported34 (link). The primary antibodies were purchased from commercial sources: rabbit anti-METTL3 (MT-A70; 15073-1-AP, Proteintech Group); rabbit anti-RUNX1T1 (15494-1-AP, Proteintech); mouse anti-β-tubulin (t-5293, Sigma); rabbit anti-m6A (202003; Synaptic Systems); mouse anti-HA (cw0092B, CWbiotech); rabbit anti-Flag (F7425, Sigma); mouse anti-Flag (F1804, Sigma). The secondary antibodies used for immunoblotting and dot-blotting: anti-Rabbit IgG-HRP (p0448, dakocytomation); anti-Mouse IgG-HRP (p0161, dakocytomation).