Geschmack ist vorhersagbar: Mit FlavorMiner. FlavorMiner heißt das Tool, das IPB-Chemiker und Partner aus Kolumbien jüngst entwickelt haben. Das Programm kann, basierend auf maschinellem Lernen (KI), anhand der…
Seit Februar 2021 bietet Wolfgang Brandt, ehemaliger Leiter der Arbeitsgruppe Computerchemie am IPB, sein Citizen Science-Projekt zur Pilzbestimmung an. Dafür hat er in regelmäßigen Abständen öffentliche Vorträge zur Vielfalt…
Li, K.; Prada, J.; Damineli, D. S. C.; Liese, A.; Romeis, T.; Dandekar, T.; Feijó, J. A.; Hedrich, R.; Konrad, K. R.;An optimized genetically encoded dual reporter for simultaneous ratio imaging of Ca2+
and H+
reveals new insights into ion signaling in plantsNew Phytol.2302292-2310(2021)DOI: 10.1111/nph.17202
Whereas the role of calcium ions (Ca2+) in plant signaling is well studied, the physiological significance of pH-changes remains largely undefined.Here we developed CapHensor, an optimized dual-reporter for simultaneous Ca2+ and pH ratio-imaging and studied signaling events in pollen tubes (PTs), guard cells (GCs), and mesophyll cells (MCs). Monitoring spatio-temporal relationships between membrane voltage, Ca2+- and pH-dynamics revealed interconnections previously not described.In tobacco PTs, we demonstrated Ca2+-dynamics lag behind pH-dynamics during oscillatory growth, and pH correlates more with growth than Ca2+. In GCs, we demonstrated abscisic acid (ABA) to initiate stomatal closure via rapid cytosolic alkalization followed by Ca2+ elevation. Preventing the alkalization blocked GC ABA-responses and even opened stomata in the presence of ABA, disclosing an important pH-dependent GC signaling node. In MCs, a flg22-induced membrane depolarization preceded Ca2+-increases and cytosolic acidification by c. 2 min, suggesting a Ca2+/pH-independent early pathogen signaling step. Imaging Ca2+ and pH resolved similar cytosol and nuclear signals and demonstrated flg22, but not ABA and hydrogen peroxide to initiate rapid membrane voltage-, Ca2+- and pH-responses.We propose close interrelation in Ca2+- and pH-signaling that is cell type- and stimulus-specific and the pH having crucial roles in regulating PT growth and stomata movement.