Figure 7. Wt Mll is required for colony formation of MA9-induced BM.

(A) A flowchart for procedures of MA9-induced transformation and 4-OHT-induced Mll excision. (B) Mll excision reduced the number of colonies from MA9-transduced BM from the Mll^f/f;Cre-ER mice. (C) 4-OHT failed to reduce colony formation of MA9 retrovirus-transduced BM from the Mll^f/f mice. (D) Genotyping with genomic DNA showed that 4-OHT induced Mll excision in MA9-transformed cells with the Mll^f/f;Cre-ER genotype (lane 2) but failed to induce Mll excision in MA9-transformed BM cells with Mll^f/f but without the Cre-ER transgene (lane 4). (E) Wt Mll excision failed to reduce Hoxa9/Meis1-induced BM colony formation (Top). 4-OHT-induced wt Mll excision in Hoxa9/Meis1-transformed BM (Bottom). (F) Wt Mll excision reduced colony formation from normal BM. BM from corn oil (CO) or TAM-treated Mll^f/f;Cre-ER mice was plated on methylcellulose medium and the colony number was scored at the first plating (Top). Wt Mll was excised in BM from TAM-treated, but not from corn oil-fed, Mll^f/f;Cre-ER mice (Bottom). (G) BM from corn oil or TAM-treated Mll^f/f;Cre-ER mice was first transduced with MA9, followed by plating on methylcellulose medium, and the colony number was scored at the first plating. Error bars denote +/− SD.