title: Translocation of bacteria from the gut to the eggs triggers maternal transgenerational immune priming in Tribolium castaneum.
abstract: Invertebrates can be primed to enhance their protection against pathogens they have encountered before. This enhanced immunity can be passed maternally or paternally to the offspring and is known as transgenerational immune priming. We challenged larvae of the red flour beetle Tribolium castaneum by feeding them on diets supplemented with Escherichia coli, Micrococcus luteus or Pseudomonas entomophila, thus mimicking natural exposure to pathogens. The oral uptake of bacteria induced immunity-related genes in the offspring, but did not affect the methylation status of the egg DNA. However, we observed the translocation of bacteria or bacterial fragments from the gut to the developing eggs via the female reproductive system. Such translocating microbial elicitors are postulated to trigger bacterial strain-specific immune responses in the offspring and provide an alternative mechanistic explanation for maternal transgenerational immune priming in coleopteran insects.
authors.affiliation: Department of Bioresources, Fraunhofer Institute for Molecular Biology and Applied Ecology, Winchester Strasse 2, 35395 Giessen, Germany.
authors.forename: Eileen
authors.initials: E
authors.lastname: Knorr
authors.affiliation: Institute for Insect Biotechnology, Justus-Liebig-University of Giessen, Heinrich-Buff-Ring 26-32, 35392 Giessen, Germany.
authors.forename: Henrike
authors.initials: H
authors.lastname: Schmidtberg
authors.affiliation: Department of Bioresources, Fraunhofer Institute for Molecular Biology and Applied Ecology, Winchester Strasse 2, 35395 Giessen, Germany.
authors.forename: Derya
authors.initials: D
authors.lastname: Arslan
authors.affiliation: Department of Bioresources, Fraunhofer Institute for Molecular Biology and Applied Ecology, Winchester Strasse 2, 35395 Giessen, Germany.
authors.forename: Linda
authors.initials: L
authors.lastname: Bingsohn
authors.affiliation: Department of Bioresources, Fraunhofer Institute for Molecular Biology and Applied Ecology, Winchester Strasse 2, 35395 Giessen, Germany Institute for Insect Biotechnology, Justus-Liebig-University of Giessen, Heinrich-Buff-Ring 26-32, 35392 Giessen, Germany andreas.vilcinskas@agrar.uni-giessen.de.
authors.forename: Andreas
authors.initials: A
authors.lastname: Vilcinskas
mesh_terms: D000818:Animals; D019175:DNA Methylation; D004926:Escherichia coli / Q000502:physiology; D005260:Female; D041981:Gastrointestinal Tract / Q000382:microbiology; D008297:Male; D016982:Micrococcus luteus / Q000502:physiology; D010063:Ovum / Q000276:immunology / Q000382:microbiology*; D011549:Pseudomonas / Q000502:physiology; D059467:Transcriptome; D014231:Tribolium / Q000235:genetics / Q000276:immunology* / Q000382:microbiology*
keywords: Tribolium castaneum; fitness costs; innate immunity; maternal inheritance; parental investment; transgenerational immune priming