Alignment of insect sNPF sequences.

<p><b>A.</b> The unique amino acid sequence of the <i>S. invicta</i> short neuropeptide F active peptide(s) is compared to those of other insect species. Aligned sNPF sequences are from (top to bottom): three ant species <i>Solin</i> (<i>Solenopsis invicta</i> KJ812404), <i>Acrec</i> (<i>Acromyrmex echinatior</i> EGI59536.1), and <i>Camfl</i> (<i>Camponotus floridanus</i> EFN66516.1); the honey bee, <i>Apime</i> (<i>Apis mellifera</i> XP_003250155.1); a basal ant, <i>Harsa</i> (<i>Harpegnathos saltator</i> EFN85447.1); the locust, <i>Schgr</i> (<i>Schistocerca gregaria</i> AHH85823.1); the flour beetle, <i>Trica</i> (<i>Tribolium castaneum</i> EEZ97763.1); dipterans, <i>Anoga</i> (<i>Anopheles gambiae</i> ABD96048.1), <i>Aedae</i> (<i>Aedes aegypti</i> ABE72968.1), and <i>Drome</i> (<i>Drosophila melanogaster</i> AAN11060.1); the brown planthopper, <i>Nillu</i> (<i>Nilaparvata lugens</i> BAO00976.1), and three lepidopterans, <i>Helar</i> (<i>Helicoverpa armigera</i> AGH25568.1), <i>Danpl</i> (<i>Danaus plexippus</i> EHJ63336.1), and <i>Bommo</i> (<i>Bombyx mori</i> NP_001127729.1). Identical amino acid residues are shaded black. In the alignment, active peptides corresponding to the location of <i>S. invicta</i> sNPFs are underlined with a solid line, and additional orthologous peptides encoded in cDNAs from other species are underlined with dashed lines. Arrowheads indicate the predicted post-translational cleavage sites for processing the prepropeptide to active peptide(s). <b>B.</b> Alignment of partial sNPF nucleotide sequences encoding the active peptide in four ant species. Identical nucleotides are shaded black. Amino acid residues for the active sNPF peptide (shaded gray) are in the middle of the respective codon; for <i>S. invicta</i> are at the top and for the other three ant species, at the bottom. The arrowhead indicates a transversion from C to G in the codon first position in <i>S. invicta</i> resulting in Ala (A), and not Pro (P) as in other ants, and the insertion of six additional nucleotides also extends the peptide length. There is a conservative replacement of R for H in <i>S. invicta</i> and F (TTT or TTC) is replaced with Y (TAC). The sequence for C-terminal α-amidation of Y or F is X-Gly-basic residue (R), and Gly provides the nitrogen for the same <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0109590#pone.0109590-Eipper1" target="_blank">[70]</a>.