title: Trans-generational Immune Priming Protects the Eggs Only against Gram-Positive Bacteria in the Mealworm Beetle.
abstract: In many vertebrates and invertebrates, offspring whose mothers have been exposed to pathogens can exhibit increased levels of immune activity and/or increased survival to infection. Such phenomena, called "Trans-generational immune priming" (TGIP) are expected to provide immune protection to the offspring. As the offspring and their mother may share the same environment, and consequently similar microbial threats, we expect the immune molecules present in the progeny to be specific to the microbes that immune challenged the mother. We provide evidence in the mealworm beetle Tenebrio molitor that the antimicrobial activity found in the eggs is only active against Gram-positive bacteria, even when females were exposed to Gram-negative bacteria or fungi. Fungi were weak inducers of TGIP while we obtained similar levels of anti-Gram-positive activity using different bacteria for the maternal challenge. Furthermore, we have identified an antibacterial peptide from the defensin family, the tenecin 1, which spectrum of activity is exclusively directed toward Gram-positive bacteria as potential contributor to this antimicrobial activity. We conclude that maternal transfer of antimicrobial activity in the eggs of T. molitor might have evolved from persistent Gram-positive bacterial pathogens between insect generations.
authors.affiliation: Équipe Écologie Évolutive, UMR CNRS 6282 BioGéoSciences, Université Bourgogne-Franche Comté, Dijon, France.
authors.forename: Aurore
authors.initials: A
authors.lastname: Dubuffet
authors.affiliation: Équipe Écologie Évolutive, UMR CNRS 6282 BioGéoSciences, Université Bourgogne-Franche Comté, Dijon, France.
authors.forename: Caroline
authors.initials: C
authors.lastname: Zanchi
authors.affiliation: Équipe Écologie Évolutive, UMR CNRS 6282 BioGéoSciences, Université Bourgogne-Franche Comté, Dijon, France.
authors.forename: Gwendoline
authors.initials: G
authors.lastname: Boutet
authors.affiliation: Équipe Écologie Évolutive, UMR CNRS 6282 BioGéoSciences, Université Bourgogne-Franche Comté, Dijon, France.
authors.forename: Jérôme
authors.initials: J
authors.lastname: Moreau
authors.affiliation: Équipe Écologie Évolutive, UMR CNRS 6282 BioGéoSciences, Université Bourgogne-Franche Comté, Dijon, France.
authors.forename: Maria
authors.initials: M
authors.lastname: Teixeira
authors.affiliation: Équipe Écologie Évolutive, UMR CNRS 6282 BioGéoSciences, Université Bourgogne-Franche Comté, Dijon, France.
authors.forename: Yannick
authors.initials: Y
authors.lastname: Moret
mesh_terms: D000818:Animals; D004531:Eggs / Q000382:microbiology*; D005260:Female; D006094:Gram-Positive Bacteria; D016908:Gram-Positive Bacterial Infections / Q000276:immunology*; D013058:Mass Spectrometry; D013712:Tenebrio / Q000276:immunology* / Q000382:microbiology