A dynamic rRNA ribomethylome drives stemness in acute myeloid leukemia.

The development and regulation of malignant self-renewal remains an unresolved issue. Here, we provide biochemical, genetic, and functional evidence that dynamics in ribosomal RNA (rRNA) 2'-O-methylation regulate leukemia stem cell (LSC) activity in vivo. A comprehensive analysis of the rRNA 2'-O-methylation landscape of 94 acute myeloid leukemia (AML) patients revealed dynamic 2'-O-methylation specifically at exterior sites of ribosomes. rRNA 2'-O-methylation pattern is closely associated with AML development stage and LSC gene expression signature. Forced expression of 2'-O-methyltransferase FBL induced an AML stem cell phenotype and enabled engraftment of non-LSC leukemia cells in NSG mice. Enhanced 2'-O-methylation redirected the ribosome translation program towards amino acid transporter mRNAs enriched in optimal codons and subsequently increased intracellular amino acid levels. Methylation at the single site 18S-guanosine 1447 was instrumental for LSC activity. Collectively, our work demonstrates that dynamic 2'-O-Me at specific sites on ribosomal RNAs shifts translational preferences and controls AML-LSC self-renewal.