Cysteine reactivity of RGS RH domains with DACM
Summary of RGS RH domain reactions with the environmentally sensitive maleimide dye DACM from kinetic traces shown in Fig. 4. Data represent mean time t1/2 as determined via fit to one phase association with the 95% CI in parentheses from n = 3 independent experiments. n.d. indicates reactivity that was undistinguishable from RGS6 and RGS7, which lack cys residues. t1/2, s (95% CI)
| RGS | No. of Cys Residues | pH 7.5 | pH 7.0 | pH 6.5 |
|---|---|---|---|---|
| 1 | 3 | 74 (69–80) | 225 (218–232) | 762 (742–781) |
| 2 | 4 | 275 (269–282) | 1170 (1140–1200) | >1000 |
| 4 | 4 | 61 (55–68) | 150 (139–162) | 316 (302–331) |
| 5 | 1 | 830 (591–1200) | 614 (508–746) | n.d. |
| 8 | 2 | 531 (355–799) | 476 (390–583) | >1000 |
| 10 | 1 | n.d. | 472 (414–539) | >1000 |
| 14 | 2 | >1000 | >1000 | >1000 |
| 16 | 3 | 224 (216–233) | 623 (605–641) | >1000 |
| 17 | 1 | n.d. | 361 (263–495) | n.d. |
| 18 | 2 | 10 (9–12) | 59 (56–63) | 244 (237–251) |