Figure 5. sandman and galene jointly encode a potassium channel.

(A) Representative whole-cell currents in physiological K⁺ and Na⁺ gradients from Sandman (n = 5), Galene (n = 6), and co-transfection of both (n = 11) during voltage steps (below). (B) Normalized whole-cell currents from voltage ramps in various bath solutions. The dotted line plots the I/V curve for a hypothetical ion channel with no rectification in symmetric K⁺. The inset plots the observed reversal potential compared to a potassium-selective conductance (dashed line) at various [K⁺] _in/out ratios. The internal pipet solution is (in mM) 150 K⁺, 5 Na⁺, 3 Mg²⁺, 161 Cl⁻, 10 HEPES, pH 7.4 (in mM). The bath solution [K⁺] and [Na⁺] or [NMDG⁺] are as indicated (in mM), excepting the ‘Divalent-free’ solution which substitutes 2 mM EDTA for the divalent cations. n = 9 cells. All pooled data represent the mean +/− s.d. All voltage potentials are relative to ground.

DOI: http://dx.doi.org/10.7554/eLife.20851.017

Figure 5—figure supplement 1. Sandman and Galene do not form functional heteromeric channels with the closely related K2P subunits CG1688 or CG10864.

Representative whole-cell currents in physiological K⁺ and Na⁺ gradients from co-transfection of Sandman + CG1688 (n = 5), Sandman + CG10864 (n = 6), Galene + CG1688 (n = 7), and Galene + CG10864 (n = 5) during voltage steps (below).

DOI: http://dx.doi.org/10.7554/eLife.20851.019