Rapid phenotypic changes in Caenorhabditis elegans under uranium exposure

• Published in: Ecotoxicology (London) Vol. 22; no. 5; pp. 862 - 868
• Main Authors: Dutilleul, Morgan, Lemaire, Laurie, Réale, Denis, Lecomte, Catherine, Galas, Simon, Bonzom, Jean-Marc
• Format: Journal Article
• Language: English
• Published: Boston Springer US 01.07.2013; Springer; Springer Nature B.V; Springer Verlag
• Subjects: Acclimation; Acclimatization; Adaptation; Adaptation, Physiological - drug effects; Adaptation, Physiological - genetics; Animals; Body Size - drug effects; Caenorhabditis elegans; Caenorhabditis elegans - drug effects; Caenorhabditis elegans - embryology; Caenorhabditis elegans - physiology; Dose-Response Relationship, Drug; Earth and Environmental Science; Ecological risk assessment; Ecology; Ecotoxicology; Embryo, Nonmammalian - drug effects; Environment; Environmental assessment; Environmental changes; Environmental Management; Environmental risk; Extinction (Biology); Genetics; Life Cycle Stages - drug effects; Life Cycle Stages - physiology; Life Sciences; Longevity - drug effects; Phenotype; Pollutants; Populations; Reproduction - drug effects; Risk Assessment; Soil Pollutants - toxicity; Species extinction; Survival; Time Factors; Uranium; Uranium Compounds - toxicity; Phenotypic changes; Experimental evolution; Uranium; Chronic exposure
• ISSN: 0963-9292; 1573-3017
• DOI: 10.1007/s10646-013-1090-9

Pollutants can induce selection pressures on populations, and the effects may be concentration-dependant. The main ways to respond to the stress are acclimation (i.e. plastic changes) and adaptation (i.e. genetic changes). Acclimation provides a short-term response to environmental changes and adaptation can have longer-term implications on the future of the population. One way of studying these responses is to conduct studies on the phenotypic changes occurring across generations in populations experimentally subjected to a selective factor (i.e. multigenerational test). To our knowledge, such studies have not been performed with uranium (U). Here, the phenotypic changes were explored across three generations in experimental Caenorhabditis elegans populations exposed to different U-concentrations. Significant negative effects of U were detected on survival, generation time, brood size, body length and body bend. At lower U-concentrations, the negative effects were reduced in the second or the third generation, indicating an improvement by acclimation. In contrast, at higher U-concentrations, the negative effects on brood size were amplified across generations. Consequently, under high U-concentrations acclimation may not be sufficient, and adaptation of individuals would be required, to permit the population to avoid extinction. The results highlight the need to consider changes across generations to enhance environmental risk assessment related to U pollution.