Table 2.
Effects of mutations on caffeine activation of RyR2
| Apparent EC50 (mm) | Adjusted p value | n number | |
|---|---|---|---|
| A. Mutations of Ca2+-coordinating residues | |||
| RyR2 WT | 0.19 ± 0.01 | -- | 4 |
| E3848A | 2.69 ± 0.22 | <0.0001 | 4 |
| E3848A/E3922A | 2.68 ± 0.17 | <0.0001 | 4 |
| H3850A | 3.98 ± 0.40 | <0.0001 | 4 |
| E3922A | 3.99 ± 0.03 | <0.0001 | 4 |
| Q3925A | 6.53 ±0.00 | <0.0001 | 4 |
| T4931A | 1.88 ± 0.13 | <0.0001 | 4 |
| ANOVA summary: F = 427.1, p value < 0.0001 | |||
| B. Mutations of residues with negatively charged or oxygen-containing side chains | |||
| RyR2 WT | 0.18 ± 0.02 | -- | 5 |
| T3929A | 0.36 ± 0.04 | 0.0003 | 5 |
| Q3932A | 0.41 ± 0.05 | 0.0008 | 5 |
| Q3933A | 0.19 ± 0.04 | 0.9956 | 5 |
| S3984A | 0.12 ± 0.01 | 0.0172 | 5 |
| N3989A | 0.19 ±0.07 | >0.9999 | 5 |
| E4146A | 1.01 ± 0.16 | 0.0019 | 5 |
| Y4149S | 0.09 ± 0.01 | 0.0021 | 5 |
| T4934A | 0.44 ± 0.05 | 0.0003 | 5 |
| Q4936A | 0.13 ± 0.02 | 0.0346 | 5 |
| E4937A | 1.05 ± 0.18 | 0.0024 | 5 |
| ANOVA summary: F = 93.0, p value < 0.0001 | |||
| C. Disease-associated mutations | |||
| RyR2 WT | 0.18 ± 0.01 | -- | 5 |
| K3997E | 0.17 ± 0.03 | 0.4697 | 5 |
| M3999V | 0.08 ± 0.01 | <0.0001 | 5 |
| F4020L | 0.10 ± 0.02 | <0.0001 | 5 |
| N4097S | 0.15 ± 0.01 | 0.0149 | 5 |
| R4157Q | 0.15 ± 0.02 | 0.0133 | 5 |
| L4188P | 0.07 ± 0.00 | <0.0001 | 5 |
| T4196A | 0.11 ± 0.01 | <0.0001 | 5 |
| Q4201R | 0.13 ± 0.01 | 0.0002 | 5 |
| ANOVA summary: F = 32.0, p value < 0.0001 | |||
Data are presented as mean ± S.D. The significance of differences in caffeine activation between WT and mutants was evaluated by performing one-way ANOVA with Dunnett's multiple comparisons post hoc testing. A p value <0.05 was considered statistically significant.