Table 1. KCNMA1 mutation effects on BK channel function.
| Mutation | BK current properties | Mechanism |
|---|---|---|
| D434G | Increased current | G-V shift to hyperpolarized potentials, increased open probability, faster activation, slower deactivation, increased Ca2+ sensitivity (Du et al., 2005; Díez-Sampedro et al., 2006; Wang et al., 2009; Yang et al., 2010; Plante et al., 2019) |
| N995/999/1053S | Increased current | G-V shift to hyperpolarized potentials, increased open probability, faster activation, slower deactivation, Ca2+-independent mechanism (Li et al., 2018; Plante et al., 2019) |
| S351Y, G356R, G375R, N449fs*, I663V | No current | Not determined (Liang et al., 2019) |
| C413Y, P805L | Reduced current | G-V shift to depolarized potentials, decreased expression (P805L; Liang et al., 2019) |
| D984N | Reduced current | Not determined (Liang et al., 2019) |
| G354S | Reduced current | Slower activation (Carvalho-de-Souza et al., 2016) |
| R458Ter, Y676Lfs*7 | Not determined | Putative truncations (Tabarki et al., 2016; Yeşil et al., 2018) |
| K518N, E656A, N1195S | No current difference | Li et al., 2018 |
| E884K | Not determined | Zhang et al., 2015 |
Dark gray, GOF mutations; light gray, LOF mutations; no shading, VUS. Full descriptions of experimental investigations for mutant channel properties are contained in Supplemental text. The N995S/N999S/N1053S mutation is reported in the literature using three different reference sequence numbering schemes but constitutes the same residue substitution (Figure 1). In this review, this mutation will be referred to by the numbering scheme in the original publication for the data being discussed.