ATE1 and leukemia: The ATE1 Arg-tRNA protein transferase (arginyltransferase or R-transferase) conjugates Arg to secondary N-terminal residues, thus converting them to primary type 1 residues.60,61 Importantly, ATE1 seems to be solely responsible for the N-terminal arginylation.62 To dissect this axis, we treated leukemia cells with tannic acid, an inhibitor of ATE1 activity,63 but could not observe any asparaginase sensitization (Figure 6C).