Activation by bombykal.

<p>(<i>A</i>) Current responses and (<i>B</i>) dose-dependent relationships obtained by challenging BmorOR1•BmorOrco-expressing oocytes with increasing concentrations of bombykol and bombykal. <i>n</i> = 6.</p

Chemical structures.

<p>Structures of the silkworm moth sex pheromone (<b>1</b>) and bombykol-related compounds, which were used to challenge BmorOR1•BmorOrco-expressing oocytes.</p

Stereochemical selectivity.

<p>(<i>A</i>) Traces and (<i>B</i>) quantification of current responses from BmorOR1•BmorOrco-expressing oocytes perfused with four isomers of bombykol at 0.1 µM. <i>n</i> = 5. Bars with the same letter arwe not significantly different (One-way ANOVA, P<0.01).</p

Effect of number of carbons distal to unsaturation.

<p>(<i>A</i>) Current responses obtained by challenging BmorOR1•BmorOrco-expressing oocytes with bombykol (lower trace, positive control), (10<i>E</i>,12<i>Z</i>)-octadecadien-1-ol (<b>7</b>), and (10<i>E</i>,12<i>Z</i>)-tetradecadien-1-ol (<b>8</b>), robust response at 10 µM. (B) Dose-dependent relationships; <i>n</i> = 4.</p

Synthetic pheromone components trapped by PBP.

<p>(<i>A</i>) Traces and (<i>B</i>) quantification of current responses obtained from the BmorOR1•BmorOrco-expressing oocytes when presented with bombykol and bombykal solubilized either by DMSO or BmorPBP1. <i>n</i> = 3. *Significantly different (t-test, P<0.05).</p

Schemes A–C.

<p>Synthetic sequence for preparation of analogues <b>7</b>–<b>11</b> containing the (<i>E</i>,<i>Z</i>)-dienyl moiety.</p

Effect of altering unsaturation on receptor response.

<p>(<i>A</i>) Traces and (<i>B</i>) quantification of current responses elicited by (8<i>E</i>,10<i>Z</i>)-hexadecadien-1-ol (<b>9</b>) and 10,12-hexadecadiyn-1-ol (<b>6</b>) presented at 1 mM. <i>n</i> = 3. Bars with the same letter are not significantly different (One-way ANOVA, P<0.01).</p

Reducing responses by adding rigidity to the C1–C9 moiety.

<p>(<i>A</i>) Current responses elicited by (10<i>E</i>,12<i>Z</i>)-hexadecadien-4-yn-1-ol (<b>10</b>), (4<i>Z</i>,10<i>E</i>,12<i>Z</i>)-hexadecatrien-1-ol (<b>11</b>), and bombykol (<b>1</b>) from BmorOR1•BmorOrco-expressing oocytes (ligands presented at 10 µM). EC₅₀s 1.7×10⁻⁵M, 1.3×10⁻⁵M, and 5.9×10⁻⁶M, respectively. (B) Dose-dependent relationships, <i>n</i> = 3–4.</p

General route for the synthesis of 13 <i>β</i>-ionone and benzaldehyde analogues (3a−m).

<p>1 =  <i>β</i>-ionone, 2a−m = 13 forms of benzaldehyde, 3a−m = 13 analogues of <i>β</i>-ionone and benzaldehyde. R is listed in <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0099142#pone-0099142-t001" target="_blank">Table 1</a>.</p

Physical properties, IR, HRMS and ¹³C NMR data for compounds 3a−m.

<p>Physical properties, IR, HRMS and ¹³C NMR data for compounds 3a−m.</p