RT Journal Article SR Electronic T1 orco mutagenesis causes loss of antennal lobe glomeruli and impaired social behavior in ants JF bioRxiv FD Cold Spring Harbor Laboratory SP 112532 DO 10.1101/112532 A1 Waring Trible A1 Ni-Chen Chang A1 Benjamin J Matthews A1 Sean K McKenzie A1 Leonora Olivos-Cisneros A1 Peter R Oxley A1 Jonathan Saragosti A1 Daniel JC Kronauer YR 2017 UL http://biorxiv.org/content/early/2017/02/28/112532.abstract AB Life inside ant colonies is orchestrated with a diverse set of pheromones, but it is not clear how ants perceive these social cues. It has been proposed that pheromone perception in ants evolved via expansions in the numbers of odorant receptors (ORs) and antennal lobe glomeruli. Here we generate the first mutant lines in ants by disrupting orco, a gene required for the function of all ORs. We find that orco mutants exhibit severe deficiencies in social behavior and fitness, suggesting that they are unable to perceive pheromones. Surprisingly, unlike in Drosophila melanogaster, orco mutant ants also lack most of the approximately 500 antennal lobe glomeruli found in wild-types. These results illustrate that ORs are essential for ant social organization, and raise the possibility that, similar to mammals, receptor function is required for the development and/or maintenance of the highly complex olfactory processing areas in the ant brain.