Cyclic AMP (cAMP) has been proposed as a key signal in the acquisition of thermotolerance, causing a calcium influx (through the activation of cyclic nucleotide-gated ion channel 6), which promotes the expression of heat shock proteins (Gao et al. 2012). To study more in detail cAMP involvement in heat stress response, we used transgenic tobacco BY-2 cells (cAS cells), overexpressing the cAMP-sponge, which is a genetic tool able to selectively reduce cAMP content (Sabetta et al. 2016). cAS cells were less tolerant to a moderate (35°C) heat stress (HS) than wild type (WT) ones. Despite the higher antioxidant activity in cAS cells with respect to WT ones at physiological temperature (27°C), these cells experienced an imbalance in redox homeostasis after HS. The low cAMP content also prevented the activation of proteases and proteasome in response to HS. A large-scale proteomic analysis showed that at 27°C cAS cells had 435 differentially accumulated proteins (DAPs) respect to WT ones, with a high down-regulation of proteins belonging to signalling and protein degradation. In response to HS, 538 DAPs were observed in cAS cells compared with WT cells. The involvement of these proteins in the impairment of heat stress response will be discussed.
|Titolo:||Genetic buffering of cAMP impairs heat stress response in tobacco BY-2 cells|
|Data di pubblicazione:||2019|
|Appare nelle tipologie:||Poster|