Fig. 2

Biochemical characterization reveals a physical link between the Hax1 C terminus and IQGAP1-CT. A, Schematic of IQGAP1 and various IQGAP1 mutants used for coimmunoprecipitation assays. Residue numbers at domain boundaries are indicated. B, Schematic of Hax1 and various Hax1 mutants used for coimmunoprecipitation assays. Residue numbers at domain boundaries are indicated. C, Hax1 binds to the IQGAP1 C terminus (CT) rather than N terminus (NT). HEK293T cells were transfected with different plasmids as indicated. Cell lysates were immunoprecipitated (IP) with HA-agarose beads and immunoblotted (IB) with different antibodies as indicated. For whole-cell lysate (WCL), 10 μg of total protein was used. Note that Hax1 specifically pulls down IQGAP1 CT. D, IQGAP1 binds to the Hax1 C terminus (CT) rather than N terminus (NT). The association of different Hax1 mutants with IQGAP1 was determined by coimmunoprecipitation as described above. For whole-cell lysate, 10 μg of total protein was used. Note that IQGAP1 specifically pulls down Hax1 CT. E and F, Hax1 binds to the IQGAP1 RGCT rather than GRD domain. The association of different IQGAP1 mutants with Hax1 was determined by coimmunoprecipitation as described above. For whole-cell lysate, 10 μg of total protein was used. Note that Hax1 specifically pulls down IQGAP1 RGCT domain. GRD, Ras GTPase-activating protein-related domain; RGCT, RasGAP C-terminus domain