Plasticity and evolution of the Caenorhabditis germline
Résumé
We are interested in understanding the mechanisms and evolution of developmental plasticity, i.e. how developmental processes change in response to the environment. As a study system, we focus on the C. elegans germline, which is a molecularly well-tractable system and shows a high degree of environmental sensitivity. We are interested in studying germ line plasticity in a range of ecologically relevant environmental conditions using a set of wild isolates from the three hermaphroditic Caenorhabditis species (C.elegans, C.briggsae and C.sp.11). In our initial analyses, we characterized how germ cell proliferation, entry into meiosis and apoptosis are modified in animals exposed to conditions, such as liquid, starvation, food source, acetic acid, temperature shifts, osmotic or oxidative stress. This data suggests that the processes occurring in the germ line are strongly responsive to changes of the environment, to ultimately affect offspring number and quality. We also find significant genotype -by-environment interaction for germline and reproductive traits, with different species showing very different reproductive schedules depending on the environment.