The Bromodomain/PHD4 of MLL and Ankyrin Repeat 1-5 of ASB2 mediate the interaction between MLL and ASB2. (A) Schematic diagram of the CxxC-PHD/Bromo serial deletions. The first and last MLL amino acid retained in the constructs are indicated. (B) CxxC-PHD/Bromo deletion constructs described in panel A were cotransfected with ASB2 into 293 cells followed by anti-Myc immunoprecipitation. Binding of ASB2 was detected by Western blotting with anti-HA antibody. (C) Schematic of HA tagged ASB2 serial deletions. The first and last ASB2 amino acid retained in the constructs are indicated. (D) ASB2 deletion constructs described in panel C were cotransfected with Myc-CxxC-PHD/Bromo in 293 cells followed by anti-Myc immunoprecipitation. Binding of ASB2 was detected by Western blotting with anti-HA antibody.