O-GlcNAcylation of BMAL1 regulates circadian rhythms in NIH3T3 fibroblasts

► Circadian core protein BMAL1 is modified with an O-linked β-N-acetylglucosamine (O-GlcNAc). ► O-GlcNAcylation of BMAL1 stabilizes the protein. ► O-GlcNAcylation of BMAL1 enhances its transcriptional activity. ► Inhibition of O-GlcNAcylation results in dampened circadian rhythms of clock gene expression.