FIG. 3.

Cytokine treatment induces MEKK-1 T1383 phosphorylation in βTC-6 cells. βTC-6 cells were either left untreated or treated with a mixture of cytokines (50 units/ml IL-1β, 1,000 units/ml IFN-γ, and 1,000 units/ml TNF-α) for 0.5, 1, or 3 h. After cytokine treatment, the cells were lysed and immunoprecipitated (IP) using MEKK-1 antibody or rabbit IgG as control. The immunoprecipitated proteins were separated by SDS gel electrophoresis and analyzed by immunoblotting using T1383 phospho–MEKK-1 and MEKK-1 antibodies (A). Results from immunoblots, as the one shown in the top panel, were quantified by densitometry (B). MEKK-1 phosphorylation was determined by relating P-MEKK-1 bands to those of total MEKK-1. Data are presented as means ± SE for four individual experiments. *P < 0.05 vs. control using Student's t test.