Adult Influence on Juvenile Phenotypes by Stage-Specific Pheromone Production

• Main Authors: Michael S. Werner, Marc H. Claaßen, Tess Renahan, Mohannad Dardiry, Ralf J. Sommer
• Format: Article
• Language: English
• Published: Elsevier 2018-12-01
• Series: iScience
• Online Access: http://www.sciencedirect.com/science/article/pii/S2589004218302177

Summary: Many animal and plant species respond to population density by phenotypic plasticity. To investigate if specific age classes and/or cross-generational signaling affect density-dependent plasticity, we developed a dye-based method to differentiate co-existing nematode populations. We applied this method to Pristionchus pacificus, which develops a predatory mouth form to exploit alternative resources and kill competitors in response to high population densities. Remarkably, adult, but not juvenile, crowding induces the predatory morph in other juveniles. High-performance liquid chromatography-mass spectrometry of secreted metabolites combined with genetic mutants traced this result to the production of stage-specific pheromones. In particular, the P. pacificus-specific di-ascaroside#1 that induces the predatory morph is induced in the last juvenile stage and young adults, even though mouth forms are no longer plastic in adults. Cross-generational signaling between adults and juveniles may serve as an indication of rapidly increasing population size, arguing that age classes are an important component of phenotypic plasticity. : Physiology; Genetics; Cell Biology; Developmental Biology Subject Areas: Physiology, Genetics, Cell Biology, Developmental Biology