TABLE 4.
Properties of 45L and S6 mutants
The values denote means ± S.E.
| RyR1 |
Po |
No. of events/min | Toa | Tcb | |
|---|---|---|---|---|---|
| 0.1 μm Ca2+ | 2 μm Ca2+ | ||||
| ms | ms | ||||
| WT | 0.005 ± 0.002 (24) | 0.27 ± 0.03 (29) | 23,821 ± 2001 (19) | 0.68 ± 0.06 (19) | 2.39 ± 0.37 (19) |
| V4830W | 0.99 ± 0.01 (16)c | 0.96 ± 0.03 (10)c | 318 ± 155 (9)c | 369.80 ± 70.8 (9)c | 1.73 ± 0.87 (9) |
| H4832W | 0.015 ± 0.014 (13) | 0.10 ± 0.03 (13)c | 13,647 ± 4235 (11)c | 0.32 ± 0.02 (11)c | 7.25 ± 1.80 (11)c |
| G4834W | 0.006 ± 0.005 (14) | 0.10 ± 0.04 (15)c | 9625 ± 2491 (10)c | 0.33 ± 0.02 (10)c | 11.69 ± 2.96 (10)c |
| V4838W | 0.026 ± 0.013 (8)c | 0.38 ± 0.07 (17) | 22,602 ± 2296 (14) | 1.72 ± 0.86 (14) | 2.22 ± 0.64 (14) |
| T4840W | 0.49 ± 0.22 (3)c | 0.83 ± 0.09 (7)c | 4120 ± 942 (6)c | 19.9 ± 8.5 (6)c | 2.26 ± 0.66 (6) |
| V4841W | 0.0003 ± 0.001 (3) | 0.20 ± 0.06 (13) | 15,982 ± 2516 (11) | 0.65 ± 0.14 (11) | 5.02 ± 1.25 (11) |
| Q4947N | 0.001 ± 0.001 (4) | 0.02 ± 0.01c (10) | 3355 ± 943c (10) | 0.36 ± 0.07c (10) | 107.63 ± 59.67c (10) |
| Q4947T | 0.003 ± 0.002 (3) | 0.03 ± 0.01c (10) | 5335 ± 1238c (10) | 0.35 ± 0.03c (10) | 24.76 ± 10.63c (10) |
| Q4947S | 0.004 ± 0.004 (4) | 0.07 ± 0.03c (11) | 10,182 ± 3534c (11) | 0.34 ± 0.03c (11) | 65.42 ± 41.82 (11) |
a Mean open time at cytoplasmic 2 μm Ca2+.
b Mean closed time at cytoplasmic 2 μm Ca2+.
c p < 0.05 compared with WT.