Get access

Molecular and social regulation of worker division of labour in fire ants

Authors

  • Fabio Manfredini,

    Corresponding author
    1. Department of Entomology, Center for Pollinator Research, The Pennsylvania State University, University Park, PA, USA
    2. School of Biological Sciences, Royal Holloway University of London, Egham, UK
    Search for more papers by this author
  • Christophe Lucas,

    1. Institut de Recherche sur la Biologie de l‘Insecte (UMR 7261), CNRS, University of Tours, Parc de Grandmont, Tours, France
    2. Department of Ecology & Evolution, University of Lausanne, Lausanne, Switzerland
    Search for more papers by this author
  • Michael Nicolas,

    1. Department of Ecology & Evolution, University of Lausanne, Lausanne, Switzerland
    Current affiliation:
    1. Department of Plants Molecular Biology, Centro Nacional de Biotecnologia, 28049, Madrid, Spain
    Search for more papers by this author
  • Laurent Keller,

    1. Department of Ecology & Evolution, University of Lausanne, Lausanne, Switzerland
    Search for more papers by this author
  • DeWayne Shoemaker,

    1. USDA-ARS, Gainesville, FL, USA
    Search for more papers by this author
  • Christina M. Grozinger

    1. Department of Entomology, Center for Pollinator Research, The Pennsylvania State University, University Park, PA, USA
    Search for more papers by this author

Abstract

Reproductive and worker division of labour (DOL) is a hallmark of social insect societies. Despite a long-standing interest in worker DOL, the molecular mechanisms regulating this process have only been investigated in detail in honey bees, and little is known about the regulatory mechanisms operating in other social insects. In the fire ant Solenopsis invicta, one of the most studied ant species, workers are permanently sterile and the tasks performed are modulated by the worker's internal state (age and size) and the outside environment (social environment), which potentially includes the effect of the queen presence through chemical communication via pheromones. However, the molecular mechanisms underpinning these processes are unknown. Using a whole-genome microarray platform, we characterized the molecular basis for worker DOL and we explored how a drastic change in the social environment (i.e. the sudden loss of the queen) affects global gene expression patterns of worker ants. We identified numerous genes differentially expressed between foraging and nonforaging workers in queenright colonies. With a few exceptions, these genes appear to be distinct from those involved in DOL in bees and wasps. Interestingly, after the queen was removed, foraging workers were no longer distinct from nonforaging workers at the transcriptomic level. Furthermore, few expression differences were detected between queenright and queenless workers when we did not consider the task performed. Thus, the social condition of the colony (queenless vs. queenright) appears to impact the molecular pathways underlying worker task performance, providing strong evidence for social regulation of DOL in S. invicta.

Get access to the full text of this article

Ancillary