title: Coevolved crypts and exocrine glands support mutualistic bacteria in fungus-growing ants.
abstract: Attine ants engage in a quadripartite symbiosis with fungi they cultivate for food, specialized garden parasites, and parasite-inhibiting bacteria. Molecular phylogenetic evidence supports an ancient host-pathogen association between the ant-cultivar mutualism and the garden parasite. Here we show that ants rear the antibiotic-producing bacteria in elaborate cuticular crypts, supported by unique exocrine glands, and that these structures have been highly modified across the ants' evolutionary history. This specialized structural evolution, together with the absence of these bacteria and modifications in other ant genera that do not grow fungus, indicate that the bacteria have an ancient and coevolved association with the ants, their fungal cultivar, and the garden parasite.
authors.affiliation: Department of Bacteriology, University of Wisconsin at Madison, Madison, WI 53706, USA. currie@bact.wisc.edu
authors.forename: Cameron R
authors.initials: CR
authors.lastname: Currie
authors.forename: Michael
authors.initials: M
authors.lastname: Poulsen
authors.forename: John
authors.initials: J
authors.lastname: Mendenhall
authors.forename: Jacobus J
authors.initials: JJ
authors.lastname: Boomsma
authors.forename: Johan
authors.initials: J
authors.lastname: Billen
mesh_terms: D000192:Actinomycetales / Q000254:growth & development / Q000502:physiology*; D000818:Animals; D000900:Anti-Bacterial Agents / Q000096:biosynthesis; D000898:Antibiosis; D001000:Ants / Q000033:anatomy & histology* / Q000382:microbiology* / Q000502:physiology / Q000648:ultrastructure; D005075:Biological Evolution; D005088:Exocrine Glands / Q000033:anatomy & histology / Q000382:microbiology; D005260:Female; D005658:Fungi / Q000254:growth & development*; D006999:Hypocreales / Q000254:growth & development*; D008855:Microscopy, Electron, Scanning; D046529:Microscopy, Electron, Transmission; D010802:Phylogeny; D013045:Species Specificity; D013559:Symbiosis
chemical_list: D000900:Anti-Bacterial Agents