Figure 5. Effect of an Irgm1 palmitoylation mutation on membrane binding.

Irgm1 KO MEF were transfected with plasmids expressing the indicated wild-type or mutant Irgm1 proteins. The cells were exposed to 100 U/ml IFN-γ for 16–18 h, and then used for preparation of detergent-free lysates that were separated into soluble (S) and membrane bound fractions (P) by centrifugation at 100,000×g. These fractions were separated on 10% SDS-PAGE gels that were used for western blotting with anti-Irgm1 and GAPDH antibodies. (A) Shown is a representative western blot, with the positions of MW markers shown at the left. (B) The percentage of the total protein that was detected in the P fraction was determined for three separate experiments. The average values are shown with error bars indicating standard error of the mean, and * indicating p<0.05 as determined using a one-sided z-distribution that was corrected for multiple comparisons.