Fig. 6. The effect of -phosphatase on HIF-1 protein in rainbow trout RTG-2 cells. Total cell protein extract was immunoprecipitated using purified C-terminal HIF-1 antibody in the presence of phosphatase inhibitors. After precipitation, the proteins bound to Sephadex-protein-A were treated with -phosphatase in the absence of phosphatase inhibitors. Notably, phosphatase treatment inhibited the broadening of the HIF-1 protein band, a finding compatible with HIF-1 protein phosphorylation.