FLT3 and acute myeloid leukemia: To evaluate the catalytic function of UBE2N in AML, we modeled AML in lineage-negative (Lin–) BM cells from Ube2nC87S;Rosa26CreERT2 or control mice by retroviral expression of MLL-AF9, MN1, AML1-ETO9a, RUNX1D171N, or FLT3-ITD AML oncogenes (Figure 2D).