title: Photoprotective function of chloroplast avoidance movement: in vivo chlorophyll fluorescence study.
abstract: Light-induced chloroplast avoidance movement has long been considered to be a photoprotective mechanism. Here, we present an experimental model in which this function can be shown for wild type Arabidopsis thaliana. We used blue light of different fluence rates for chloroplast positioning, and strong red light inactive in chloroplast positioning as a stressing light. The performance of photosystem II was measured by means of chlorophyll fluorescence. After stressing light treatment, a smaller decrease in photosystem II quantum yield was observed for leaves with chloroplasts in profile position as compared with leaves with chloroplasts in face position. Three Arabidopsis mutants, phot2 (no avoidance response), npq1 (impaired zeaxanhtin accumulation) and stn7 (no state transition), were examined for their chloroplast positioning and chlorophyll fluorescence parameters under identical experimental conditions. The results obtained for these mutants revealed additional stressing effects of blue light as compared with red light.
authors.affiliation: Department of Plant Biotechnology, Faculty of Biochemistry, Biophysics and Biotechnology, Jagiellonian University, Kraków, Poland.
authors.forename: Olga
authors.initials: O
authors.lastname: Sztatelman
authors.forename: Andrzej
authors.initials: A
authors.lastname: Waloszek
authors.forename: Agnieszka Katarzyna
authors.initials: AK
authors.lastname: Banaś
authors.forename: Halina
authors.initials: H
authors.lastname: Gabryś
mesh_terms: D017360:Arabidopsis / Q000378:metabolism* / Q000528:radiation effects; D029681:Arabidopsis Proteins / Q000235:genetics / Q000378:metabolism; D002734:Chlorophyll / Q000378:metabolism*; D002736:Chloroplasts / Q000378:metabolism* / Q000528:radiation effects; D005453:Fluorescence; D018506:Gene Expression Regulation, Plant / Q000528:radiation effects; D008027:Light
chemical_list: D029681:Arabidopsis Proteins; D002734:Chlorophyll