FIGURE 1.

Representative model of hPAR₁ displaying the five potential N-linked glycosylation sequons and potential proteinase cleavage sites at the extracellular N terminus. Three sequons are located on the receptor N terminus (Asn³⁵-Ala³⁶-Thr³⁷, Asn⁶²-Glu⁶³-Ser⁶⁴, and Asn⁷⁵-Lys⁷⁶-Ser⁷⁷) and two are located within extracellular loop 2 (ECL2; Asn²⁵⁰-Ile²⁵¹-Thr²⁵⁴ and Asn²⁵⁹-Glu²⁶⁰-Thr²⁶¹). Of the sequons at the N terminus, one (Asn³⁵-Ala³⁶-Thr³⁷) is located N-terminal of the cleavage/activation site (R⁴¹↓S⁴²FLLR), and the remaining two (Asn⁶²-Glu⁶³-Ser⁶⁴ and Asn⁷⁵-Lys⁷⁶-Ser⁷⁷) are located downstream of the cleavage/activation site. The disulfide bridge is shown by the two cysteines (C-C). The red arrows indicate the preferential cleavage site for each proteinase. TH, thrombin; TRY, trypsin; THE, thermolysin; PR3, proteinase 3; CG, cathepsin G; ELA, elastase. This figure was adapted from Refs. 4, 12, 13, and 29.