title: Reproduction-Immunity Trade-Offs in Insects.
abstract: Immune defense and reproduction are physiologically and energetically demanding processes and have been observed to trade off in a diversity of female insects. Increased reproductive effort results in reduced immunity, and reciprocally, infection and activation of the immune system reduce reproductive output. This trade-off can manifest at the physiological level (within an individual) and at the evolutionary level (genetic distinction among individuals in a population). The resource allocation model posits that the trade-off arises because of competition for one or more limiting resources, and we hypothesize that pleiotropic signaling mechanisms regulate allocation of that resource between reproductive and immune processes. We examine the role of juvenile hormone, 20-hydroxyecdysone, and insulin/insulin-like growth factor-like signaling in regulating both oogenesis and immune system activity, and propose a signaling network that may mechanistically regulate the trade-off. Finally, we discuss implications of the trade-off in an ecological and evolutionary context.
authors.affiliation: Field of Genetics, Genomics, and Development.|Department of Entomology.
authors.forename: Robin A
authors.initials: RA
authors.lastname: Schwenke
authors.affiliation: Field of Genetics, Genomics, and Development.|Department of Entomology.
authors.forename: Brian P
authors.initials: BP
authors.lastname: Lazzaro
authors.affiliation: Field of Genetics, Genomics, and Development.|Department of Molecular Biology and Genetics, Cornell University, Ithaca, New York 14853; email: ras599@cornell.edu , bplazzaro@cornell.edu , mfw5@cornell.edu.
authors.forename: Mariana F
authors.initials: MF
authors.lastname: Wolfner
mesh_terms: D000818:Animals; D007107:Immune System; D007301:Insect Hormones / Q000378:metabolism; D007313:Insecta / Q000276:immunology / Q000502:physiology*; D007328:Insulin / Q000378:metabolism; D009866:Oogenesis; D015398:Signal Transduction; D013002:Somatomedins / Q000378:metabolism
chemical_list: D007301:Insect Hormones; D007328:Insulin; D013002:Somatomedins
keywords: egg production; hormones; infection; life-history trade-off; resource allocation; signaling pleiotropy