FIGURE 4.

FOG1 is SUMOylated on lysines K469R and K507R. Constructs in which all six putative SUMOylated lysines were mutated to arginine in FOG1 cDNA were co-expressed along with a GFP-SUMO1 fusion protein. Immunoprecipitation was performed on whole cell lysates with a FOG1 antibody, and input and immunoprecipitates (IP) were run for Western blot with anti-FOG1 or anti-GFP (A). After identification of lysines 469 and 507 as the SUMOylated lysines, a construct containing mutations in which both lysines were mutated to arginine was made and used in immunoprecipitation experiments along with constructs for wild-type FOG1 and both single lysine 469 and 507 single mutants. Western blot analysis using antibodies against FOG1 or GFP was performed for these FOG1 versions (B).