title: Fitness analyses of Arabidopsis thaliana mutants depleted of FtsH metalloproteases and characterization of three FtsH6 deletion mutants exposed to high light stress, senescence and chilling.
abstract: Darwinian fitness analyses were performed, comparing single ftsh mutants with wild-type Arabidopsis thaliana plants grown under controlled laboratory conditions and in the field, by measuring plant size, survival rate, and silique and seed production. Additionally, three genotypes of ΔFtsH6 were analysed, under controlled growth conditions, with respect to both their ability to degrade the light-harvesting complex of photosystem II during senescence and light acclimation. In the field, substantial increases in variegation and reductions in growth were observed in the ΔFtsH2, ΔFtsH5 and ΔFtsH10 mutants; FtsH2 seemed particularly important for plant survival. Despite being grown in relatively cold weather, the ΔFtsH11 mutant displayed strong phenotypic deviations from wild type. Both ΔFtsH10 and ΔFtsH3 mutants exhibited less severe phenotypic changes, but were different from wild-type plants when placed in the field as young plants. When older ΔFtsH3 or ΔFtsH10 mutants were placed outdoors, no phenotypic differences from wild type were observed. Three genotypes of ΔFtsH6 displayed no phenotypic deviations from wild-type plants. Under controlled growth conditions, during senescence and light acclimation, no differences in the amount of chlorophyll or Photosystem II light-harvesting complex b3 (Lhcb3) were detected in ΔFtsH6 mutants compared with the wild type. Therefore, FtsH6 seems to be unimportant for LHCII degradation in vivo.
authors: Department of Chemistry, Umeå Plant Science Centre, Umeå University, S-901 87 Umeå, Sweden.
authors: Raik
authors: R
authors: Wagner
authors: Department of Chemistry, Umeå Plant Science Centre, Umeå University, S-901 87 Umeå, Sweden.
authors: Harald
authors: H
authors: Aigner
authors: Department of Chemistry, Umeå Plant Science Centre, Umeå University, S-901 87 Umeå, Sweden.
authors: Adriana
authors: A
authors: Pružinská
authors: Department of Plant Physiology, Umeå Plant Science Centre, Umeå University, S-901 87 Umeå, Sweden.
authors: Hanna Johansson
authors: HJ
authors: Jänkänpää
authors: Department of Plant Physiology, Umeå Plant Science Centre, Umeå University, S-901 87 Umeå, Sweden.
authors: Stefan
authors: S
authors: Jansson
authors: Department of Chemistry, Umeå Plant Science Centre, Umeå University, S-901 87 Umeå, Sweden.
authors: Christiane
authors: C
authors: Funk
mesh_terms: D017360:Arabidopsis / Q000201:enzymology / Q000235:genetics / Q000378:metabolism / Q000528:radiation effects*; D029681:Arabidopsis Proteins / Q000235:genetics / Q000378:metabolism; D002734:Chlorophyll / Q000378:metabolism; D002736:Chloroplasts / Q000378:metabolism; D003080:Cold Temperature; D005838:Genotype; D008027:Light; D045342:Light-Harvesting Protein Complexes / Q000235:genetics / Q000378:metabolism; D045726:Metalloproteases / Q000235:genetics / Q000378:metabolism*; D010641:Phenotype; D010788:Photosynthesis; D045332:Photosystem II Protein Complex / Q000235:genetics / Q000378:metabolism*; D018515:Plant Leaves / Q000235:genetics / Q000378:metabolism / Q000528:radiation effects; D017384:Sequence Deletion; D013312:Stress, Physiological; D013997:Time Factors
chemical_list: D029681:Arabidopsis Proteins; D045342:Light-Harvesting Protein Complexes; D045332:Photosystem II Protein Complex; D002734:Chlorophyll; D045726:Metalloproteases