title: Phenotypical consequences of expressing the dually targeted Presequence Protease, AtPreP, exclusively in mitochondria.
abstract: Endosymbiotic organelles, mitochondria and chloroplasts, are sites of an intensive protein synthesis and degradation. A consequence of these processes is production of both free targeting peptides, i.e. mitochondrial presequences and chloroplastic transit peptides, and other short unstructured peptides. Mitochondrial, as well as chloroplastic peptides are degraded by Presequence Protease (PreP), which is dually targeted to mitochondrial matrix and chloroplastic stroma. Elimination of PreP in Arabidopsis thaliana leads to growth retardation, chlorosis and impairment of mitochondrial functions potentially due to the accumulation of targeting peptides. In this work we analyzed the influence of the restoration of mitochondrial peptide degradation by AtPreP on plant phenotype. We showed that exclusive mitochondrial expression of AtPreP results in total restoration of the proteolytic activity, but it does not restore the wild-type phenotype. The plants grow shorter roots and smaller rosettes compared to the plants expressing AtPreP1 in both mitochondria and chloroplasts. With this analysis we are aiming at understanding the physiological impact of the role of the dually targeted AtPreP in single type of destination organelle.
authors.affiliation: Department of Biochemistry and Biophysics, Stockholm University, Arrhenius Laboratories for Natural Sciences, SE-106 91 Stockholm, Sweden.
authors.forename: Beata
authors.initials: B
authors.lastname: Kmiec
authors.affiliation: Department of Biochemistry and Biophysics, Stockholm University, Arrhenius Laboratories for Natural Sciences, SE-106 91 Stockholm, Sweden.
authors.forename: Pedro F
authors.initials: PF
authors.lastname: Teixeira
authors.affiliation: Department of Biochemistry and Biophysics, Stockholm University, Arrhenius Laboratories for Natural Sciences, SE-106 91 Stockholm, Sweden. Electronic address: e_glaser@dbb.su.se.
authors.forename: Elzbieta
authors.initials: E
authors.lastname: Glaser
mesh_terms: D017360:Arabidopsis / Q000235:genetics* / Q000254:growth & development / Q000378:metabolism; D029681:Arabidopsis Proteins / Q000037:antagonists & inhibitors / Q000235:genetics; D002736:Chloroplasts / Q000235:genetics* / Q000378:metabolism; D018507:Gene Expression Regulation, Developmental; D018506:Gene Expression Regulation, Plant; D005816:Genetic Complementation Test; D005838:Genotype; D008928:Mitochondria / Q000235:genetics* / Q000378:metabolism; D010447:Peptide Hydrolases / Q000172:deficiency / Q000235:genetics; D010641:Phenotype; D018517:Plant Roots / Q000235:genetics* / Q000254:growth & development / Q000378:metabolism; D030821:Plants, Genetically Modified; D059748:Proteolysis
chemical_list: D029681:Arabidopsis Proteins; D010447:Peptide Hydrolases; C511107:presequence protease PreP, Arabidopsis
keywords: Dual targeting; Mitochondria; Peptide degradation; Presequence Protease