Offre de stage M2: The mechanisms and genetic basis of heat-induced male infertility

Climate change threatens global biodiversity in many ways, including via insults to animal fertility that can occur upon exposure to extreme environmental conditions. With regard to the most frequently-studied climate change component of temperature, this has prompted a recent shift away from ‘critical thermal limits’, based solely on where animals are able to survive, towards so-called ‘critical fertility limits’ that take into account the temperature range in which animals can reproduce. There is thus an urgent need to better understand the links between climate stressors such as temperature and basic aspects of reproductive biology that ultimately drive fertility and fitness outcomes, both to forecast the declines in fertility we might expect to observe under current climate change scenarios and predict the capacity for both plastic and evolutionary responses in fertility traits that might mitigate these impacts. We are currently developing the free- living flatworm Macrostomum lignano as a model system to investigate the effects of heat and salinity on fertility, based on useful features such as its transparency (permitting in vivo observations of sperm production and storage) and simultaneous hermaphroditism (allowing to directly compare impacts on male and female gametogenesis). The internship would build on our emerging results documenting the susceptibility of these flatworms to heat- and salinity-induced infertility, with a particular focus on (1) defining thresholds of exposure that cause a breakdown in spermatogenesis; and (2) whether there exists genetic variation in this trait suggestive of the capacity for it to evolve.

The internship will be based at the Ecobio lab (UMR 6553 CNRS) on the Beaulieu Campus, Université de Rennes, and will contribute to the ongoing Chaire de Recherche Rennes Métropole / Chaire de Professeur Junior project “Fertility in a Changing World”. You will join four researchers already working on different aspects of the project, providing an excellent environment for interaction and collaboration. You will be trained in appropriate experimental and analytical approaches, including extensive use of photomicroscopy to accurately record fertility phenotypes.

For more information or to apply (with a CV, letter of motivation and contact details of 1 or 2 potential referees), please email Steven Ramm (steven.ramm@univ-rennes.fr)