Deciphering the effect of temperature on circadian clock performance in trees
Circadian clock increases organism’s fitness by providing a mechanism to anticipate events such as sunrise and adjust their transcriptional programs (Webb et al. 2019, Nature Communications 10:550). Due to its ability to maintain 24h-rhythms over a wide range of temperatures, circadian clocks have been proposed to contribute to thermal adaptation and plasticity in plants (Resco et al. 2009, Ecology letters 12:583). However, consequences of clock performance on plant behavior in natural ecosystems are scarcely known. This constitutes relevant information to understand and predict the effect of climate change on plant behavior. In this talk I will show the way in which we use indoor experiments in combination with trials in a natural laboratory in the mountains to explore the influence of temperature on the performance of circadian clocks in trees. I will show genomic, biochemical and eco-physiological experiments that provide evidence in favor that differences between species in the influence of temperature on the performance of their circadian clocks contribute to physiological adaptation of trees to the local thermic environment. Our experimental system is located in the southernmost woody ecosystem of the world: the sub-Antarctic temperate forests of Patagonia where two species of the genera Nothofagus which belongs to the order Fagales, are sharply distributed along altitudinal gradients, inhabiting non-overlapping thermal niches.