Table 1

Analysis of PAR-1 mutants expressed in X. laevis oocytes

ConstructEC50
ThrombinSFLLRNP-NH2
nM μM
Wild-type0.05  ± 0.040.5  ± 0.3
Deletions
 ΔNH3 (68–93)1  ± 0.8>10
 ΔEC1 (163–174)>10NT
 ΔEC2 (240–267)>10NT
 ΔEC3 (339–344)0.1  ± 0.06>50
Point mutants
 F87A0.05  ± 0.040.5  ± 0.3
 I88A0.05  ± 0.0330  ± 15
 S89A0.05  ± 0.0430  ± 18
 D91N0.05  ± 0.030.5  ± 0.2
 S93A0.05  ± 0.020.5  ± 0.3
 Y95A0.05  ± 0.040.5  ± 0.3
 L96A0.05  ± 0.0420  ± 10
 EC1DE (D167A/E173A)0.05  ± 0.030.5  ± 0.3
 EC2DE (E241A, D256A, E260A, E264A)>10>40
 E241A0.05  ± 0.040.5  ± 0.3
 D256A0.1  ± 0.07>40
 D256N0.05  ± 0.045  ± 3
 E260A0.05  ± 0.030.5  ± 0.4
 E264A0.05  ± 0.040.5  ± 0.3
 E347A0.1  ± 0.08>50
 E347Q0.5  ± 0.3>40
 C175S10  ± 2>40
 C175S, C254S10  ± 1>40

Wild-type or mutant PAR-1 receptors were expressed in X. laevis oocytes and EC50 values for 45Ca efflux in response to thrombin and SFLLRNP were evaluated. Responses were determined as a percentage of the control value, which was the maximum response of PAR-1 to either thrombin or SFLLRNP. EC50 values shown are representative of those obtained in at least two separate experiments performed in triplicate.

    • NT, not tested: the mutants that were not responsive to thrombin were not tested for TRAP responses.