FIG. 4.

The AFX CR3 interacts in vitro with the KIX domain of CBP. (A) GST pull-down experiments were conducted with in vitro translated [³⁵S]methionine-labeled proteins indicated on the left. GST constructs are indicated at the top of gel lanes. GST-CBP constructs have been previously described (58). (B) Mapping of KIX interacting domain to CR3 of AFX. Various AFX fragments (indicated by horizontal bars on left) were in vitro translated with [³⁵S]methionine and incubated with GST (lane 2) or GST-KIX (lane 3) fusion proteins. Bound proteins were washed, eluted, and subjected to SDS-PAGE after autoradiography. Protein inputs are shown in lane 1. (C) In vivo interaction between CBP and AFX proteins. Constructs used in cell transfection are shown at the top of each lane and their expression was confirmed by Western blots (bottom panel). Cell lysates were precipitated with antibodies to MLL or Gal4 DBD and then blotted with anti-CBP antibody. Specific 265-kDa CBP bands are indicated in the top panel.