14th POG 2019 - Plant Oxygen Group Meeting, Munich, Germany, 10 - 13 July 2019, pp.45
Break-down of lipids in cell membranes by ROS causes producƟon of lipid peroxidaƟon products such as 4-
hydroxy-2-nonenal (HNE), 4-hydroxy-2-hexenal (HHE), and acrolein (ACR) which are called as reacƟve carbonyl
species (RCS). Although there are studies about RCS in animals, studies in plants are limited, which mostly
invesƟgate their detoxificaƟon mechanisms. The aim of this work was to understand RCS metabolism and its
signalling comparaƟvely in glycophyte Arabidopsis thaliana and halophyte Eutrema parvulum, which is important
for elucidaƟon of new mechanisms related to salt stress tolerance. RCS profiles of A. thaliana and E. parvulum
were determined under salinity (50 mM-600 mM NaCl) and also the acƟviƟes of RCS detoxificaƟon enzymes
aldehyde dehydrogenase (ALDH), alkenal reductase (AER), aldo-keto reductase (AKR), glutathione-S-transferase
(GST) were measured. The effects of exogenous RCS (HNE, HHE, ACR) on the acƟviƟes of RCS detoxificaƟon
enzymes (ALDH, AER, AKR, GST) and the acƟviƟes of anƟoxidant defence system were also elucidated. ROS
signalling also cross-talk stress hormones such as ABA, JA, SA under stress. Therefore, the effects of exogenous
RCS on contents of ABA, JA and SA were determined. Morevoer, effects of RCS on expression of ion transporters
were also invesƟgated. Data provided evidence for regulaƟon of anƟoxidant defence enzymes and ROS signalling
in plants depending on the type and concentraƟon of the RCS. In regards of glycophyte and halophyte
comparison, remarkable differences were, (i) response of A. thaliana H2O2 scavenging enzymes (CAT, POX, APX)
was stronger to RCS treatment (ii) NADPH oxidase mediated ROS signalling was downregulated in A. thaliana in
response to RCS. In addiƟon, gene expression data demonstrated that RCS treatments induced SOS1, NHX1 and
NHX5 expression depending on type and concentraƟon of RCS. Moreover, growth data indicate that RCS
treatments can miƟgate negaƟve effects of salt stress in E. parvulum.