TY  - JOUR
A1  - Münch, Miriam
A1  - Hsin, Chih-Hsuan
A1  - Ferber, Elena
A1  - Berger, Susanne
A1  - Müller, Martin J.
T1  - Reactive electrophilic oxylipins trigger a heat stress-like response through HSFA1 transcription factors
JF  - Journal of Experimental Botany
N2  - Electrophilic oxylipins trigger a heat-shock-like response in the absence of heat through the canonical heat-shock transcription factor A1, thereby helping to cope with stresses associated with protein damage.Abiotic and biotic stresses are often characterized by an induction of reactive electrophile species (RES) such as the jasmonate 12-oxo-phytodienoic acid (OPDA) or the structurally related phytoprostanes. Previously, RES oxylipins have been shown massively to induce heat-shock-response (HSR) genes including HSP101 chaperones. Moreover, jasmonates have been reported to play a role in basal thermotolerance. We show that representative HSR marker genes are strongly induced by RES oxylipins through the four master regulator transcription factors HSFA1a, b, d, and e essential for short-term adaptation to heat stress in Arabidopsis. When compared with Arabidopsis seedlings treated at the optimal acclimation temperature of 37 A degrees C, the exogenous application of RES oxylipins at 20 A degrees C induced a much weaker induction of HSP101 at both the gene and protein expression levels which, however, was not sufficient to confer short-term acquired thermotolerance. Moreover, jasmonate-deficient mutant lines displayed a wild-type-like HSR and were not compromised in acquiring thermotolerance. Hence, the OPDA- and RES oxylipin-induced HSR is not sufficient to protect seedlings from severe heat stress but may help plants to cope better with stresses associated with protein unfolding by inducing a battery of chaperones in the absence of heat.
KW  - arabidopsis-thaliana
KW  - shock response
KW  - gene-expression
KW  - model
KW  - acquired thermotolerance
KW  - 12-oxo-phytodienoic acid
KW  - thermotolerance
KW  - plants
KW  - detoxification
KW  - acquisition
KW  - activation
KW  - heat stress
KW  - jasmonates
KW  - phytoprostanes
KW  - reactive electrophilic species
KW  - unfolded protein response
Y1  - 2016
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-186766
VL  - 67
IS  - 21
ER  - 
TY  - JOUR
A1  - Nukarinen, Ella
A1  - Nägele, Thomas
A1  - Pedrotti, Lorenzo
A1  - Wurzinger, Bernhard
A1  - Mair, Andrea
A1  - Landgraf, Ramona
A1  - Börnke, Frederik
A1  - Hanson, Johannes
A1  - Teige, Markus
A1  - Baena-Gonzalez, Elena
A1  - Dröge-Laser, Wolfgang
A1  - Weckwerth, Wolfram
T1  - Quantitative phosphoproteomics reveals the role of the AMPK plant ortholog SnRK1 as a metabolic master regulator under energy deprivation
JF  - Scientific Reports
N2  - Since years, research on SnRK1, the major cellular energy sensor in plants, has tried to define its role in energy signalling. However, these attempts were notoriously hampered by the lethality of a complete knockout of SnRK1. Therefore, we generated an inducible amiRNA::SnRK1α2 in a snrk1α1 knock out background (snrk1α1/α2) to abolish SnRK1 activity to understand major systemic functions of SnRK1 signalling under energy deprivation triggered by extended night treatment. We analysed the in vivo phosphoproteome, proteome and metabolome and found that activation of SnRK1 is essential for repression of high energy demanding cell processes such as protein synthesis. The most abundant effect was the constitutively high phosphorylation of ribosomal protein S6 (RPS6) in the snrk1α1/α2 mutant. RPS6 is a major target of TOR signalling and its phosphorylation correlates with translation. Further evidence for an antagonistic SnRK1 and TOR crosstalk comparable to the animal system was demonstrated by the in vivo interaction of SnRK1α1 and RAPTOR1B in the cytosol and by phosphorylation of RAPTOR1B by SnRK1α1 in kinase assays. Moreover, changed levels of phosphorylation states of several chloroplastic proteins in the snrk1α1/α2 mutant indicated an unexpected link to regulation of photosynthesis, the main energy source in plants.
KW  - phosphoproteomics
KW  - SnRK1
KW  - energy deprivation
KW  - plants
Y1  - 2016
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-167638
VL  - 6
IS  - 31697
ER  -