Foreseen climate change involves, among other effects, increases of temperature in many areas of the globe, with heat waves occurring more often and lasting longer. These changes are expected to affect crop growth, reproduction and yield causing huge economic losses in agriculture.
Heat response is a complex trait and depends on different aspects as heat intensity and duration, the rate of increase in temperature or the plant developmental stage among others.
In many plant species, an exposure to a sublethal temperature triggers an adaptative response called acclimation. This response involves an extensive molecular reprogramming that allows the plant to further survive to an otherwise lethal increase of temperature. A related response is also launched under an abrupt and lethal heat stress that, in this case, is unable to successfully promote thermotolerance and therefore ends up in plant death. Although these molecular programs are expected to have common players, the overlapping degree and the specific regulators of each process are currently unknown.
To answer these questions, researchers form CBGP and CNIC, led by Dr. Mar Castellano, have carried out a proteomics study to analyse the changes in the proteome during the early stages of the plant response to a severe heat stress that lead Arabidopsis seedlings either to survival or death. This analysis dissects these responses, unravels the common players and identifies the specific proteins associated with these different fates. In addition, this study has allowed the identification and the analysis of different key proteins involved in the plant response to high temperatures but whose role in the heat stress response was not previously characterised.
Thermotolerance assays showing that 7 day-old Arabidopsis seedlings are able to cope with a severe heat stress of 45ºC for 3h when they have been exposed to a prior acclimation period of 38ºC for 1h (A). However, similar plants are unable to survive to the same abrupt treatment without acclimation (B). Plants were photographed 7 days after the last heat stress treatment. In the original article, the changes in the proteome at different time-points of these two treatments are compared