title: Identification of a slowly inducible zeaxanthin-dependent component of non-photochemical quenching of chlorophyll fluorescence generated under steady-state conditions in Arabidopsis.
abstract: The induction and relaxation of non-photochemical quenching (NPQ) under steady-state conditions, i.e. during up to 90min of illumination at saturating light intensities, was studied in Arabidopsis thaliana. Besides the well-characterized fast qE and the very slow qI component of NPQ, the analysis of the NPQ dynamics identified a zeaxanthin (Zx) dependent component which we term qZ. The formation (rise time 10-15min) and relaxation (lifetime 10-15min) of qZ correlated with the synthesis and epoxidation of Zx, respectively. Comparative analysis of different NPQ mutants from Arabidopsis showed that qZ was clearly not related to qE, qT or qI and thus represents a separate, Zx-dependent NPQ component.
authors.affiliation: Biochemie der Pflanzen, Heinrich-Heine-Universität Düsseldorf, Düsseldorf, Germany.
authors.forename: Manuela
authors.initials: M
authors.lastname: Nilkens
authors.forename: Eugen
authors.initials: E
authors.lastname: Kress
authors.forename: Petar
authors.initials: P
authors.lastname: Lambrev
authors.forename: Yuliya
authors.initials: Y
authors.lastname: Miloslavina
authors.forename: Marc
authors.initials: M
authors.lastname: Müller
authors.forename: Alfred R
authors.initials: AR
authors.lastname: Holzwarth
authors.forename: Peter
authors.initials: P
authors.lastname: Jahns
mesh_terms: D017360:Arabidopsis / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism; D002734:Chlorophyll / Q000737:chemistry* / Q000378:metabolism; D005453:Fluorescence; D006863:Hydrogen-Ion Concentration; D007700:Kinetics; D008954:Models, Biological; D008956:Models, Chemical; D009154:Mutation; D055668:Photochemical Processes / Q000528:radiation effects; D010777:Photochemistry; D010788:Photosynthesis / Q000528:radiation effects; D013050:Spectrometry, Fluorescence; D024341:Xanthophylls / Q000737:chemistry* / Q000378:metabolism; D065146:Zeaxanthins
chemical_list: D024341:Xanthophylls; D065146:Zeaxanthins; D002734:Chlorophyll