@Article{IPB-2160, author = {Ibañez, C. and Delker, C. and Martinez, C. and Bürstenbinder, K. and Janitza, P. and Lippmann, R. and Ludwig, W. and Sun, H. and James, G. V. and Klecker, M. and Grossjohann, A. and Schneeberger, K. and Prat, S. and Quint, M.}, title = {{Brassinosteroids Dominate Hormonal Regulation of Plant Thermomorphogenesis via BZR1}}, year = {2018}, pages = {303-310.e3}, journal = {Curr Biol}, doi = {10.1016/j.cub.2017.11.077}, url = {http://www.cell.com/current-biology/abstract/S0960-9822(17)31602-0}, volume = {28}, abstract = {Thermomorphogenesis is defined as the suite of morphological changes that together are likely to contribute to adaptive growth acclimation to usually elevated ambient temperature [ 1, 2 ]. While many details of warmth-induced signal transduction are still elusive, parallels to light signaling recently became obvious (reviewed in [ 3 ]). It involves photoreceptors that can also sense changes in ambient temperature [ 3–5 ] and act, for example, by repressing protein activity of the central integrator of temperature information PHYTOCHROME-INTERACTING FACTOR 4 (PIF4 [ 6 ]). In addition, PIF4 transcript accumulation is tightly controlled by the evening complex member EARLY FLOWERING 3 [ 7, 8 ]. According to the current understanding, PIF4 activates growth-promoting genes directly but also via inducing auxin biosynthesis and signaling, resulting in cell elongation. Based on a mutagenesis screen in the model plant Arabidopsis thaliana for mutants with defects in temperature-induced hypocotyl elongation, we show here that both PIF4 and auxin function depend on brassinosteroids. Genetic and pharmacological analyses place brassinosteroids downstream of PIF4 and auxin. We found that brassinosteroids act via the transcription factor BRASSINAZOLE RESISTANT 1 (BZR1), which accumulates in the nucleus at high temperature, where it induces expression of growth-promoting genes. Furthermore, we show that at elevated temperature BZR1 binds to the promoter of PIF4, inducing its expression. These findings suggest that BZR1 functions in an amplifying feedforward loop involved in PIF4 activation. Although numerous negative regulators of PIF4 have been described, we identify BZR1 here as a true temperature-dependent positive regulator of PIF4, acting as a major growth coordinator.} } @Article{IPB-2237, author = {Wasternack, C. and Strnad, M.}, title = {{Jasmonates: News on Occurrence, Biosynthesis, Metabolism and Action of an Ancient Group of Signaling Compounds}}, year = {2018}, pages = {2539}, journal = {Int J Mol Sci}, doi = {10.3390/ijms19092539}, url = {https://dx.doi.org/10.3390/ijms19092539}, volume = {19}, abstract = {Jasmonic acid (JA) and its related derivatives are ubiquitously occurring compounds of land plants acting in numerous stress responses and development. Recent studies on evolution of JA and other oxylipins indicated conserved biosynthesis. JA formation is initiated by oxygenation of α-linolenic acid (α-LeA, 18:3) or 16:3 fatty acid of chloroplast membranes leading to 12-oxo-phytodienoic acid (OPDA) as intermediate compound, but in Marchantiapolymorpha and Physcomitrellapatens, OPDA and some of its derivatives are final products active in a conserved signaling pathway. JA formation and its metabolic conversion take place in chloroplasts, peroxisomes and cytosol, respectively. Metabolites of JA are formed in 12 different pathways leading to active, inactive and partially active compounds. The isoleucine conjugate of JA (JA-Ile) is the ligand of the receptor component COI1 in vascular plants, whereas in the bryophyte M. polymorpha COI1 perceives an OPDA derivative indicating its functionally conserved activity. JA-induced gene expressions in the numerous biotic and abiotic stress responses and development are initiated in a well-studied complex regulation by homeostasis of transcription factors functioning as repressors and activators.} } @Article{IPB-1902, author = {Strehmel, N. and Mönchgesang, S. and Herklotz, S. and Krüger, S. and Ziegler, J. and Scheel, D.}, title = {{Piriformospora indica Stimulates Root Metabolism of Arabidopsis thaliana}}, year = {2016}, pages = {1091}, journal = {Int J Mol Sci}, doi = {10.3390/ijms17071091}, url = {https://dx.doi.org/10.3390/ijms17071091}, volume = {17}, abstract = {Piriformospora indica is a root-colonizing fungus, which interacts with a variety of plants including Arabidopsis thaliana. This interaction has been considered as mutualistic leading to growth promotion of the host. So far, only indolic glucosinolates and phytohormones have been identified as key players. In a comprehensive non-targeted metabolite profiling study, we analyzed Arabidopsis thaliana’s roots, root exudates, and leaves of inoculated and non-inoculated plants by ultra performance liquid chromatography/electrospray ionization quadrupole-time-of-flight mass spectrometry (UPLC/(ESI)-QTOFMS) and gas chromatography/electron ionization quadrupole mass spectrometry (GC/EI-QMS), and identified further biomarkers. Among them, the concentration of nucleosides, dipeptides, oligolignols, and glucosinolate degradation products was affected in the exudates. In the root profiles, nearly all metabolite levels increased upon co-cultivation, like carbohydrates, organic acids, amino acids, glucosinolates, oligolignols, and flavonoids. In the leaf profiles, we detected by far less significant changes. We only observed an increased concentration of organic acids, carbohydrates, ascorbate, glucosinolates and hydroxycinnamic acids, and a decreased concentration of nitrogen-rich amino acids in inoculated plants. These findings contribute to the understanding of symbiotic interactions between plant roots and fungi of the order of Sebacinales and are a valid source for follow-up mechanistic studies, because these symbioses are particular and clearly different from interactions of roots with mycorrhizal fungi or dark septate endophytes } } @Article{IPB-831, author = {Schilling, S. and Stenzel, I. and von Bohlen, A. and Wermann, M. and Schulz, K. and Demuth, H.-U. and Wasternack, C.}, title = {{Isolation and characterization of the glutaminyl cyclases from Solanum tuberosum and Arabidopsis thaliana: implications for physiological functions}}, year = {2007}, pages = {145-153}, journal = {Biol. Chem}, doi = {10.1515/BC.2007.016}, volume = {388}, }