MLLT3 and leukemia: For example, UTX is a coactivator of TAL1 and removes H3K27me at the TAL1 target locus, allowing TAL1-mediated activation of a leukemic program.138 JMJD1C functions as a coactivator for the AML1-ETO-containing AETFC complex to drive leukemic programs by maintaining low H3K9me2 levels.139 JMJD1C is also an important mediator of MLL-AF9-driven and HOXA9-driven leukemia stem cell (LSC) function (Fig. 5).