Two distinct mechanisms lead to either oocyte or spermatocyte decrease in < i > C < /i > . < i > elegans < /i > after whole developmental exposure to γ-rays

by Elizabeth Dufourcq Sekatcheff, Christian Godon, Aymeric Bailly, Lo ïc Quevarec, Virginie Camilleri, Simon Galas, Sandrine Frelon Wildlife is subject to various sources of pollution, including ionizing radiation. Adverse effects can impact the survival, growth, or reproduction of organisms, later affecting population dynamics. In invertebrates, reproduction, which directly impacts population dynamics, has been found to be th e most radiosensitive endpoint. Understanding the underlying molecular pathways inducing this reproduction decrease can help to comprehend species-specific differences in radiosensitivity. From our previous studies, we found that decrease in reproduction is life stage dependent in the roundwormCaenorhabditis elegans, possibly resulting from an accumulation of damages during germ cell development and gamete differentiation. To go further, we used the same experimental design to assess more precisely the molecular determinants of reproductive toxicity, primarily decreases in gamete number. As before, worms were chronically exposed to 50 mGy ·h−1 external gamma ionizing radiation throughout different developmental periods (namely embryogenesis, gametogenesis, and full development). To enable cross species extrapolation, conserved molecular pathways across invertebrates and vertebrates were analysed: apoptosis and MAP kinase Ras/ERK (MPK-1), both involved in reproduction and stress responses. Our results showed that these pathways are life-stage depend...
Source: PLoS One - Category: Biomedical Science Authors: Source Type: research