Antarctic microfungi as models for exobiology

Microfungi living in different Antarctic environments are generally well adapted to high stress conditions such as low temperatures, wide thermal fluctuations, high UV irradiance, and low water and nutrients availability; for this reason they could be investigated in order to explore limits of microbial life. Microfungi living in simple cryptoendolithic microbial communities inside the porosity of rocks in the Antarctic Dry Valleys, the closest terrestrial analogue of Mars, are particularly suitable for exobiological studies. Until now studies on exobiology focused mainly on prokaryotes; since cryptoendolithic black meristematic fungi are able to tolerate hard desiccation, high UV exposure, extremely low temperatures and wide thermal fluctuations, they are proposed as the best eukaryotic models for the biological exploration of Mars. Indeed, their adaptive strategies could be crucial as predictive tools in investigating the limits of life.