Table 2.
Hill Equation Parameters for Fits to Calmodulin Concentration Dependence of Inhibition of Sarcoplasmic Reticulum Vesicle [3H]Ryanodine Binding
| wild type | L3 PEST | L6 NP | oxidized L6 NP | wild type | L5 NTerm | oxidized L5 NTerm | wild type | L4 CTerm | oxidized L4 CTerm | |
|---|---|---|---|---|---|---|---|---|---|---|
| inhibition (% maximal binding) | 12.1 ± 1.0 | 9.4 ± 1.2 | 9.2 ± 0.7 | 7.2 ± 1.4a | 15.0 ± 0.8 | 10.7 ± 0.8a | 7.2 ± 1.4a,b | 17.5 ± 1.7 | 15.8 ± 1.1 | 10.3 ± 2.3a |
| nic | −1.99 ± 0.53 | −2.84 ± 1.33 | −3.18 ± 0.93 | −2.12 ± 1.41 | −2.10 ± 0.38 | −3.77 ± 1.34 | −2.37 ± 2.09 | −1.78 ± 0.53 | −1.6 ± 0.34 | −2.39 ± 1.8 |
| IC50c(nM) | 27.8 ± 4.0 | 35.8 ± 7.5 | 37.8 ± 4.7 | 20.5 ± 6.8 | 31.3 ± 3.0 | 30.9 ± 3.0 | 248.3 ± 96.1a,b | 37.9 ± 7.4 | 53.7 ± 7.8 | 47.5 ± 18.8 |
| nc | 4 | 4 | 4 | 4 | 6 | 6 | 6 | 10 | 10 | 10 |
Significantly different (p < 0.05) from wild type.
Significantly different (p < 0.05) from unoxidized.
ni, the Hill coefficient of ryanodine binding; IC50, the concentration of CaM required to achieve half-inhibition of ryanodine binding; n, number of separate experiments performed.