Figure 8.

Proteosome inhibitor lactacystin does not inhibit desaturase degradation. Experimental conditions were as in Figure 4 except for addition of lactacystin in the indicated sample lanes. The incubation temperature and the final concentration of lactacystin in the samples are shown at the top of the panel. Lanes 1 and 2 represent incubation mixtures containing 10–15 μg of microsomes. Lanes 3 and 4, microsomes and P-2 fraction; lanes 5–8, samples containing 10–15 μg of P-2 fraction. Before the SDS-PAGE, 125 μl of the loading buffer containing SDS, β-mercaptoethanol, glycerol, and tracking dye were added, and 10-μl samples were run on duplicate gels. (A) Coomassie Blue-stained gel. (B) Immunoblot of the above gel with desaturase antibody.