Figure 1.

PZ-128. A, The activated structure of PAR1 (protease-activated receptor 1; on-state: chartreuse) bound to intracellular G protein was modeled on the x-ray structure of the β2-adrenergic receptor (purple) bound to Gs (red) and the x-ray structure of PAR1 in the (B) off-state (orange).³³ PZ-128 (white), is a N-palmitoylated peptide (palmitate-KKSRALF) derived from the juxtamembrane region of the third intracellular (i3) loop-transmembrane 6 segments of PAR1.¹⁴ PZ-128 rapidly flips across the lipid bilayer to the intracellular surface where it specifically inhibits signaling between PAR1 and associated G proteins.