Pre-copulatory reproductive behaviours are preserved in Drosophila melanogaster infected with bacteria.
Authors: Saloni Rose 1; Esteban Beckwith 2,3; Charlotte Burmester 1; Robin May 4; Marc Dionne 2; Carolina Rezaval 1
Affiliations: 1) University of Birmingham; 2) MRC Centre for Molecular Bacteriology and Infection and Department of Life Sciences, Imperial College London, London SW7 2AZ, United Kingdom; 3) Instituto de Fisiología, Biología Molecular y Neurociencias (IFIBYNE), UBA-CONICET, Buenos Aires, Argentina; 4) Institute of Microbiology & Infection, University of Birmingham, Birmingham B15 2TT, United Kingdom
Keywords: g. courtship and mating; c. innate immunity
The activation of the immune system upon infection exerts a huge energetic demand on an individual, decreasing available resources for other vital processes, such as reproduction. However, the factors that determine the trade-off between defensive and reproductive traits remain poorly understood. Here, we exploit the experimental malleability of the fruit fly Drosophila melanogaster to systematically assess the impact of immune system activation on pre-copulatory reproductive behaviour. Contrary to our expectations, we found that male flies undergoing an immune activation continue to display high levels of courtship and mating success. Similarly, immune-challenged female flies remain highly sexually receptive. By combining behavioural paradigms, a diverse panel of pathogens and genetic strategies to induce both arms of the fly immune system, we show that pre-copulatory reproductive behaviours are preserved in infected flies, despite the huge metabolic cost of infection.