title: Involvement of Deg5 protease in wounding-related disposal of PsbF apoprotein.
abstract: Deg5 is a serine-type protease peripherally attached to luminal side of thylakoid membrane. Given the lack of knowledge concerning its function homozygous T-DNA insertion line depleted in Deg5 was prepared to study the functional importance of this protease in Arabidopsis thaliana. deg5 mutants displayed a pleiotropic phenotype with regard to fourth whorl leaves of four-weeks old plants. The alterations involved an increased leaf area, reduced leaf thickness, reduced cross-sectional area of palisade mesophyll cells as well as changed chloroplast ultrastructure including lack of signs of entering the senescence phase (e.g. presence of much smaller plastoglobules) and the accumulation of large starch grains at the end of the dark period. It was shown that whereas PsbA, C and F apoproteins of photosystem II reaction center undergo an extensive disappearance in response to a set of brief stresses deg5 mutant was fully resistant to the disappearance of PsbF apoprotein which follows an exposition of leaves to wounding. Our results demonstrate that Deg5 is of seminal importance for normal plant development and degradation of PsbF which occurs following brief wounding.
authors.affiliation: Department of Plant Physiology, Institute of Experimental Biology, Faculty of Biology, Adam Mickiewicz University, ul. Umultowska 89, Poznań, Poland. rtl@amu.edu.pl
authors.forename: Robert
authors.initials: R
authors.lastname: Luciński
authors.forename: Lucyna
authors.initials: L
authors.lastname: Misztal
authors.forename: Sławomir
authors.initials: S
authors.lastname: Samardakiewicz
authors.forename: Grzegorz
authors.initials: G
authors.lastname: Jackowski
mesh_terms: D000222:Adaptation, Physiological / Q000235:genetics*; D001059:Apoproteins / Q000378:metabolism; D017360:Arabidopsis / Q000235:genetics / Q000254:growth & development / Q000378:metabolism*; D029681:Arabidopsis Proteins / Q000235:genetics / Q000378:metabolism*; D002736:Chloroplasts / Q000648:ultrastructure; D004269:DNA, Bacterial; D003624:Darkness; D016254:Mutagenesis, Insertional; D010641:Phenotype; D045332:Photosystem II Protein Complex / Q000378:metabolism*; D010935:Plant Diseases / Q000235:genetics*; D018515:Plant Leaves / Q000033:anatomy & histology / Q000378:metabolism; D012697:Serine Endopeptidases / Q000235:genetics / Q000378:metabolism*; D013213:Starch / Q000378:metabolism; D013312:Stress, Physiological / Q000235:genetics*
chemical_list: D001059:Apoproteins; D029681:Arabidopsis Proteins; D004269:DNA, Bacterial; D045332:Photosystem II Protein Complex; C036483:T-DNA; D013213:Starch; C436319:SPPA protein, Arabidopsis; D012697:Serine Endopeptidases