Figure 4

Reinstating the WT ICD in zebrafish GlyR_EM decreases agonist efficacy.A, upper panel, whole cell current responses to glycine, β-alanine, taurine, and GABA of zebrafish WT α1 GlyR. A, lower panel, averaged concentration-response curves to glycine (black), β-alanine (blue), taurine (red), and GABA (green) on zebrafish α1 GlyR. Each curve is constructed from pooling individual concentration-response curves obtained in different cells (n = 6–10). Error bars represent S.E. Responses are normalized to the response to 10 mm glycine in each cell. B, cell-attached recordings of clusters of zebrafish α1 single-channel activity evoked by saturating agonist concentrations (10 mm glycine, 30 mmβ-alanine, 100 mm taurine, 100 mm GABA). C, boxplot of the maximum P_open values produced by saturating concentrations of different agonists for zebrafish α1 GlyR_EM (black, left hand side), zebrafish α1 GlyR ΔICD (dark gray in the middle), and zebrafish α1 GlyR (blue, right hand side). Each point is a P_open value from a cluster of single-channel activity. Boxes and whiskers show the 25th and 75th percentiles and the furthest points that fall within 1.5 times of the interquartile range from the 25th to 75th percentiles, respectively. The horizontal line in the box is the median. Asterisks and brackets denote differences that reached statistical significance (randomization test, two tail, unpaired; 10,000 iterations; p < 0.005).