Figure 6. Effect of peptides from p24 cargo proteins on Arf GAP2 activity. A. Sequence of peptides used. B. Peptide titration.
Peptides fromp23, p24 and p25 were titrated into a reaction containing LUVs containing PI4P and extruded through 0.03 μm pores, 0.6 μM [α32P]GTP•myrArf1, 11.4 nM [1–521] Arf GAP2 His6 and 124 nM coatomer. Reactions were terminated after 3 min at 30 °C. C. Effect of palmitoylated peptide. P25 peptide with palmitic acid- WRM or WRM modifying the N-terminus was titrated into a GAP reaction as described in B. The data were fit to a one site binding model with an offset.