Table 3. Basic response-shaping parameters of MEM fitting of SPRs shown in Fig. 5.
| Parameter | Units | NR | Forsk. | |
|---|---|---|---|---|
| Dark cGMP turnover rate | Pd | s−1 | 0.625 | 0.21 |
| Dark cGMP concentration | cGd | µM | 3 | 3 |
| Fraction of dark current carried by Ca2+ | fCa | - | 0.15 | 0.25 |
| Dark Ca2+ concentration | Cad | µM | 0.5 | 0.75 |
| Fast cytoplasmic Ca2+ turnover rate | β | s−1 | 3.2 | 2.2 |
| Maximum guanylate cyclase activity at 0 Ca2+ | αmax | µM⋅s−1 | 12.4 | 12 |
| Rate of Rh turn-off at Cad | Rhd | s−1 | 0.964 | 0.81 |
| Rate of inactivation of light-activated PDE | kE | s−1 | 3 | 1.1 |
| Rate of PDE activation by R* | νRE | s−1 | 200 | 180 |