Skip to main content
ARS Home » Northeast Area » Beltsville, Maryland (BARC) » Beltsville Agricultural Research Center » Bee Research Laboratory » Research » Publications at this Location » Publication #309031

Title: A depauperate immune repertoire precedes evolution of sociality in bees

item BARRIBEAU, SETH - Eth Zurich
item SADD, BEN - Illinois State University
item DU PLESSIS, LOUIS - Eth Zurich
item BROWN, MARK - University Of London
item BUECHEL, SEVERINE - Eth Zurich
item CAROLAN, JAMES - National University Of Ireland
item CHRISTIAENS, OLIVIER - Ghent University
item COLGAN, THOMAS - Trinity College
item ERLER, SILVIO - University Of Agricultural Sciences And Veterinary Medicine - Romania
item Evans, Jay
item HELBING, SOPHIE - Martin Luther University
item KARAUS, ELKE - Eth Zurich
item LATTORFF, MICHAEL - Martin Luther University
item MARXER, MONIKA - Eth Zurich
item MEEUS, IVAN - Ghent University
item NAPFLIN, KATHRIN - Eth Zurich
item SMAGGHE, GUY - Ghent University
item WATERHOUSE, ROBERT - University Of Geneva
item YU, NA - Ghent University
item ZDOBNOV, EVGENY - University Of Geneva
item SCHMID-HEMPEL, PAUL - Eth Zurich

Submitted to: Genome Biology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 3/11/2015
Publication Date: 4/24/2015
Citation: Barribeau, S.M., Sadd, B.M., Du Plessis, L., Brown, M.J., Buechel, S.D., Carolan, J.C., Christiaens, O., Colgan, T.J., Erler, S., Evans, J.D., Helbing, S., Karaus, E., Lattorff, M.G., Marxer, M., Meeus, I., Napflin, K., Schmid-Hempel, R., Smagghe, G., Waterhouse, R.M., Yu, N., Zdobnov, E.M., Schmid-Hempel, P. 2015. A depauperate immune repertoire precedes evolution of sociality in bees. Genome Biology. 16:83.

Interpretive Summary: Social insects defend themselves against parasites and pathogens using behaviour and physiological defenses. This study explores immune defense found in honey bees, two bumble bee species and a solitary pollinator, the alfalfa leafcutting bee. All of these groups show a similar set of immune genes, stressing the importance of immunity across the bees, and indicating additional targets for selection of robust honey bees for agriculture.

Technical Abstract: Sociality has many rewards, but it can also be dangerous, as high population density and low genetic diversity, common in many social insects, is ideal for parasite transmission. Social insects may therefore be expected to have evolved a specialised immune arsenal to guard against this threat. Surprisingly, the honeybee genome, which was the first social insect genome sequenced, revealed a dramatic reduction in the number of canonical immune-related genes relative to the genomes of solitary insects. Social protection from infection, including behavioural responses, may explain the honeybee's depauperate immune repertoire. Here we describe the immunological properties based on full genome sequencing of two ecologically and commercially important species of bumblebees (Bombus impatiens and B. terrestris) separated by ~18 million years and the Atlantic Ocean. We find remarkable similarity among the immune systems of these bumblebees and to those of the western honeybee (Apis mellifera), the dwarf honeybee (A. florea), and the solitary leafcutting bee (Megachile rotundata) across 27 immune-related gene families suggesting that a reduced immune repertoire predates the evolution of sociality in bees. Bumblebees diverged from Apis and Megachile ~70 and ~105 MYA respectively. The evolution of behavioural defences to parasitism thus appear to have emerged after the evolution of high-density insect societies comprised of highly-related individuals, rather than being a precondition for such evolution. Transcriptional assays confirm the activity of a number of these predicted immune genes in an immunological context, including several novel genes. These differences may reflect the divergent pressures exerted by parasites across social contexts.