Parameters and initial conditions for the fitting
| Row | Parameters (unit) | Setting | Initial value of TRPC6 endo/C6 + M1R/A7r5/C7 + M1R | Source or comments |
| 1 | PI(4,5)P2 (µM) at resting | Free | 20/20/20/20 | Bunce et al., 1993; McLaughlin and Murray, 2005 |
| 2 | ki_PLC (s−1) | Free | 0.04/1/1/1 | Rational to PI(4,5)P2 reduction with our data |
| 3 | kii_DAG kinase (s−1) | Free | 0.03/0.03/0.08/0.03 | Rational to DAG changes with our data |
| 4 | kiii_PA to PIP reactions (s−1) | Free | 0.01/0.01/0.01/0.01 | Appropriate for PI(4,5)P2 synthesis |
| 5 | kiv_PIP5K (s−1) | Free | 0.1/0.1/0.25/0.1 | Appropriate for PI(4,5)P2 resynthesis |
| 6 | kv_IP3 phosphatase (s−1) | Free | 0.5/0.5/0.5/0.5 | Appropriate for IP3 hydrolysis |
| 7 | τrd (s) | Free | 5/2/1/4 | Appropriate for Receptor desensitization |
| 8 | τsd (s) | Free | 50/10/5/10 | Same as above |
| 9 | Rd_f (no unit) | Free | 0.5/0.5/0.5/0.5 | Same as above |
| 10 | Sd_f (no unit) | Free | 0.5/0.5/0.5/0.5 | Same as above |
| 11 | spot (distance global to local; µm) | Free | 4/4/3/4 | 5 times more than the diffusion coefficient of PI(4,5)P2 |
| 12 | dcoef of PI(4,5)P2 (µm2/s) | Free | 0.8/0.8/0.8/0.8 | Golebiewska et al., 2008 |
| 13 | Ratio of local ki / global ki | Free | 1/4/2/5 | Approximate from the uneven FRET reduction (Fig. S3) |
| 14 | PI4P (µM) | Fixed | 10/10/10/10 | Brown et al., 2008 |
| 15 | Activation delay (no unit) | Free | 0.01/0.001/0.001/0.001 | Appropriate for receptor activation |
| 16 | Activation power (no unit) | Free | 0.5/0.3/0.7/0.3 | Same as above |
| 17 | Vrev (mV) | Fixed | 0/0/0/0 | |
| 18 | Vhold (mV) | Fixed | −50/−50/−50/−50 | |
| 19 | No. of channels | Free | 100–7,000 | Appropriate for the current density |
| 20 | Channel conductance (pS) | Fixed | 35/35/35/70 | Hofmann et al., 1999; Lemonnier et al., 2008 |
| 21 | K1 (Kd for DAG1; µM) | Free | 60/60/35/10 | Effective OAG concentrations are 10 to 100 µM in Hofmann et al., 1999; Okada et al., 1999; Imai et al., 2012 |
| 22 | K2 (Kd for DAG2; µM) | Free | 30/30/10/10 | Same as above |
| 23 | K3 (Kd for PI(4,5)P2; µM) | Free | 2/2/5/5 | This paper, Fig. 4 D |
| 24 | Expressed PHd (µM) | Fixed | 1.6/1.6/1.6/1.6 | This paper, Materials and methods |
| 25 | Kd PI(4,5)P2 of PHd (µM) | Fixed | 2.0/2.0/2.0/2.0 | Hirose et al., 1999 |
| 26 | Kd IP3 of PHd (µM) | Fixed | 0.1/0.1/0.1/0.1 | Hirose et al., 1999 |
| Row | Parameters (unit) | Setting | Initial value of TRPC6 endo/C6 + M1R/A7r5/C7 + M1R | Source or comments |
| 1 | PI(4,5)P2 (µM) at resting | Free | 20/20/20/20 | Bunce et al., 1993; McLaughlin and Murray, 2005 |
| 2 | ki_PLC (s−1) | Free | 0.04/1/1/1 | Rational to PI(4,5)P2 reduction with our data |
| 3 | kii_DAG kinase (s−1) | Free | 0.03/0.03/0.08/0.03 | Rational to DAG changes with our data |
| 4 | kiii_PA to PIP reactions (s−1) | Free | 0.01/0.01/0.01/0.01 | Appropriate for PI(4,5)P2 synthesis |
| 5 | kiv_PIP5K (s−1) | Free | 0.1/0.1/0.25/0.1 | Appropriate for PI(4,5)P2 resynthesis |
| 6 | kv_IP3 phosphatase (s−1) | Free | 0.5/0.5/0.5/0.5 | Appropriate for IP3 hydrolysis |
| 7 | τrd (s) | Free | 5/2/1/4 | Appropriate for Receptor desensitization |
| 8 | τsd (s) | Free | 50/10/5/10 | Same as above |
| 9 | Rd_f (no unit) | Free | 0.5/0.5/0.5/0.5 | Same as above |
| 10 | Sd_f (no unit) | Free | 0.5/0.5/0.5/0.5 | Same as above |
| 11 | spot (distance global to local; µm) | Free | 4/4/3/4 | 5 times more than the diffusion coefficient of PI(4,5)P2 |
| 12 | dcoef of PI(4,5)P2 (µm2/s) | Free | 0.8/0.8/0.8/0.8 | Golebiewska et al., 2008 |
| 13 | Ratio of local ki / global ki | Free | 1/4/2/5 | Approximate from the uneven FRET reduction (Fig. S3) |
| 14 | PI4P (µM) | Fixed | 10/10/10/10 | Brown et al., 2008 |
| 15 | Activation delay (no unit) | Free | 0.01/0.001/0.001/0.001 | Appropriate for receptor activation |
| 16 | Activation power (no unit) | Free | 0.5/0.3/0.7/0.3 | Same as above |
| 17 | Vrev (mV) | Fixed | 0/0/0/0 | |
| 18 | Vhold (mV) | Fixed | −50/−50/−50/−50 | |
| 19 | No. of channels | Free | 100–7,000 | Appropriate for the current density |
| 20 | Channel conductance (pS) | Fixed | 35/35/35/70 | Hofmann et al., 1999; Lemonnier et al., 2008 |
| 21 | K1 (Kd for DAG1; µM) | Free | 60/60/35/10 | Effective OAG concentrations are 10 to 100 µM in Hofmann et al., 1999; Okada et al., 1999; Imai et al., 2012 |
| 22 | K2 (Kd for DAG2; µM) | Free | 30/30/10/10 | Same as above |
| 23 | K3 (Kd for PI(4,5)P2; µM) | Free | 2/2/5/5 | This paper, Fig. 4 D |
| 24 | Expressed PHd (µM) | Fixed | 1.6/1.6/1.6/1.6 | This paper, Materials and methods |
| 25 | Kd PI(4,5)P2 of PHd (µM) | Fixed | 2.0/2.0/2.0/2.0 | Hirose et al., 1999 |
| 26 | Kd IP3 of PHd (µM) | Fixed | 0.1/0.1/0.1/0.1 | Hirose et al., 1999 |