Dem IPB wird erneut ein beispielhaftes Handeln im Sinne einer chancengleichheitsorientierten Personal- und Organisationspolitik bescheinigt. Das Institut erhält zum 6. Mal in Folge das TOTAL E-QUALITY…
Die Plant Science Student Conference (PSSC) wird seit 20 Jahren im jährlichen Wechsel von Studierenden der beiden Leibniz-Institute IPK und IPB organisiert. Im Interview erläutern Christina Wäsch…
Floss, D. S.; Walter, M. H.;Role of carotenoid cleavage dioxygenase 1 (CCD1) in apocarotenoid biogenesis revisitedPlant Signal Behav.4172-175(2009)DOI: 10.4161/psb.4.3.7840
Oxidative tailoring of C40 carotenoids by double bond-specific cleavage enzymes (carotenoid cleavage dioxygenases, CCDs) gives rise to various apocarotenoids. AtCCD1 generating C13 and C14 apocarotenoids and orthologous enzymes in other plants are the only CCDs acting in the cytosol, while the hitherto presumed C40 substrate is localized in the plastid. A new model for CCD1 action arising from a RNAi-mediated CCD1 gene silencing study in mycorrhizal hairy roots of Medicago truncatula may solve this contradiction. This approach unexpectedly resulted in the accumulation of C27 apocarotenoids but not C40 carotenoids suggesting C27 as the main substrates for CCD1 in planta. It further implies a consecutive two-step cleavage process, in which another CCD performs the primary cleavage of C40 to C27 in the plastid followed by C27 export and further cleavage by CCD1 in the cytosol. We compare the specificities and subcellular locations of the various CCDs and propose the plastidial CCD7 to be the first player in mycorrhizal apocarotenoid biogenesis.
Publikation
Bethke, G.; Scheel, D.; Lee, J.;Sometimes new results raise new questions: the question marks between mitogen-activated protein kinase and ethylene signalingPlant Signal Behav.4672-674(2009)DOI: 10.4161/psb.4.7.9039
In Arabidopsis thaliana, mitogen activated protein kinase (MAPK) signaling cascades that contain MPK3, MPK4 and MPK6 have been implicated in various aspects of developmental processes and stress responses. We identified an ethylene response factor (ERF104), which controls innate immunity, to be a specific substrate of MPK6 and showed that ethylene signaling regulates the release of the ERF104 substrate from its kinase. Implications and questions that arise from our findings are addressed. To promote discussions, previously unpublished data, that are rather confounding, are presented and possible explanation provided on how these may fit into our current model.