ERGs at 6 dpf in the presence of drugs suggest alterations in GABAergic signaling.

<p>A) In 50 µM DNQX, which isolates the ON–bipolar cells, WT and <i>celsr3</i> mutant eyes have a similar response suggesting that ON-bipolar cells are normal (see <a href="http://www.plosgenetics.org/article/info:doi/10.1371/journal.pgen.1002239#s2" target="_blank">Results</a>), and it is ionotropic glutamate responses that are defective. B) The DNQX sensitive curve is obtained by subtracting the DNQX-treated waveform from the untreated response <a href="http://www.plosgenetics.org/article/info:doi/10.1371/journal.pgen.1002239#pgen.1002239-Nelson1" target="_blank">[23]</a>. The isolated DNQX sensitive b-wave element is called b1. The b1 element is larger in <i>celsr3</i> mutants. C) The WT and <i>celsr3</i> mutant response is similar in 25 µM picrotoxin, a GABA_A/C inhibitor, suggesting that changes to GABA signaling are causing the increase in the <i>celsr3</i> mutant b1-wave. Black bar indicates 3 sec. light pulse. Graphs are the average of at least 6 animals.