| Summary: | During early development the vertebrate body plan is established by gradients of signaling molecules, so-called morphogens, that lead to different transcriptional responses in target tissues. In the wild, embryos encounter a wide range of temperature regimes, such as the cold of the arctic or the heat of tropical ecosystems. Also, day and night temperatures vary considerably. Since the temperature is typically kept constant in laboratory environments, little is known about how morphogen gradients are affected by these shifts in temperature and how embryos, especially of eurytherm species, cope with this stress. The Einstein-Stokes equation demonstrates that free diffusion scales linearly with the temperature in kelvin and therefore changes very little at physiological temperatures. Enzymatic reactions, on the contrary, change their speed by a factor of 2-3 for every 10°C within biologically relevant ranges, described by the Q10 rule. In this project, we are analyzing the effect of temperature fluctuations on Nodal-mediated germ layer patterning in teleost fish. Our primary model organism are eurytherm medaka (Oryzias latipes) embryos, due to their wide temperature tolerance and the ability to resume development after temperature-induced arrest. We are applying a combination of live imaging of signaling molecules at endogenous levels with measurements of their biophysical properties to mathematically model and experimentally test the effect of temperature fluctuations on morphogen gradient formation and interpretation. This will help us to understand the influence of ecological factors on embryogenesis and evolution of externally developing, eurytherm species, and the mechanisms of robustness towards these factors.
|
|---|