Calcium imaging reveals that <i>ppk25</i> cells respond specifically to female pheromones.

<p>A. Solutions (100 ng/µl in 10%hexane, 90% water) of 7,11-HD (HD), 7,11-ND (ND), 7T, cVA, a mixture of all pheromones (mix) or 10% hexane, 90% water solution alone (hex) were applied to single leg bristles of <i>ppk25-Gal4</i>, <i>20×UAS-GCaMP3</i> flies. “<i>wt</i>” flies contained one copy of the normal <i>ppk25</i> gene. <i>ppk25 null</i> mutants were heterozygous for two different deletions of the <i>ppk25</i> locus <a href="http://www.plosgenetics.org/article/info:doi/10.1371/journal.pgen.1004238#pgen.1004238-Lin1" target="_blank">[16]</a>, and “<i>ppk25</i> rescue” flies are <i>ppk25</i> mutants carrying <i>UAS-ppk25</i> and <i>ppk25-Gal4</i> transgenes to target <i>ppk25</i> expression to <i>ppk25</i> cells <a href="http://www.plosgenetics.org/article/info:doi/10.1371/journal.pgen.1004238#pgen.1004238-Starostina1" target="_blank">[10]</a>. “#” denotes pheromones that did not elicit responses significantly higher than hexane alone in “<i>wt</i>” flies and were not tested further. n = 7–10; Mean ± SEM; ttest to <i>wt</i>, *p<0.05, **p<0.01. B. The same pheromone solutions as in A were applied to single leg bristles of <i>ppk25</i> mutants carrying the <i>ppk23-Gal4</i> and <i>20×UAS-GCaMP3</i> transgenes. As previously observed in flies with normal <i>ppk25</i> genes <a href="http://www.plosgenetics.org/article/info:doi/10.1371/journal.pgen.1004238#pgen.1004238-Thistle1" target="_blank">[13]</a>, one population of <i>ppk23</i> cells, the M cells, respond specifically to male pheromones. In contrast to <i>wt</i> males however, in <i>ppk25 null</i> mutants the second population of <i>ppk23</i> cells, corresponding to F cells does not respond to any pheromone. n = 8; Mean ± SEM; ttest to <i>wt</i>,*p<0.05,**p<0.01.