Sex-specific variation in the emphasis, inducibility and timing of the post-mating immune response in Drosophila melanogaster

    Authors

    W. E. Winterhalter;K. M. Fedorka

    Abbreviated Journal Title

    Proc. R. Soc. B-Biol. Sci.

    Keywords

    mating; immunity; sexual dimorphism; specificity; inducibility; Drosophila; SEXUALLY-TRANSMITTED-DISEASE; TIME QUANTITATIVE PCR; LIFE-HISTORY; PHENOLOXIDASE ACTIVITY; ECOLOGICAL IMMUNOLOGY; EVOLUTIONARY ECOLOGY; PARASITE RESISTANCE; BATEMANS PRINCIPLE; SYSTEM ACTIVATION; INNATE; IMMUNITY; Biology; Ecology; Evolutionary Biology

    Abstract

    Ecological immunology attempts to explain variation in immune function. Much of this work makes predictions about how potential hosts should invest in overall immunity. However, this 'overall' perspective under-emphasizes other critical aspects, such as the specificity, inducibility and timing of an immune response. Here, we investigate these aspects by examining gene regulation across several immune system components in both male and female Drosophila melanogaster prior to and after mating. To elucidate potentially important temporal dynamics, we also assayed several genes over time. We found that males and females emphasized different components of their immune system, however overall investment was similar. Specifically, the sexes emphasized different gene paralogues within major gene families, and males tended to invest more in gram-negative defence. By contrast, the inducibility of the immune response was both transient (lasting approx. 24 hours) and equal between the sexes. Furthermore, mating tended to induce humoral gene upregulation, while cell-mediated genes were unaffected. Within the humoral system, gram-negative bacterial defence genes exhibited a greater inducibility than those associated with fungal or gram-positive bacterial defence. Our results suggest that variation in the effectiveness of the immune response between the sexes may be driven by differences in emphasis rather than overall investment.

    Journal Title

    Proceedings of the Royal Society B-Biological Sciences

    Volume

    276

    Issue/Number

    1659

    Publication Date

    1-1-2009

    Document Type

    Article

    Language

    English

    First Page

    1109

    Last Page

    1117

    WOS Identifier

    WOS:000263148000017

    ISSN

    0962-8452

    Share

    COinS