title: Proteome analysis of peroxisomes from etiolated Arabidopsis seedlings identifies a peroxisomal protease involved in β-oxidation and development.
abstract: Plant peroxisomes are highly dynamic organelles that mediate a suite of metabolic processes crucial to development. Peroxisomes in seeds/dark-grown seedlings and in photosynthetic tissues constitute two major subtypes of plant peroxisomes, which had been postulated to contain distinct primary biochemical properties. Multiple in-depth proteomic analyses had been performed on leaf peroxisomes, yet the major makeup of peroxisomes in seeds or dark-grown seedlings remained unclear. To compare the metabolic pathways of the two dominant plant peroxisomal subtypes and discover new peroxisomal proteins that function specifically during seed germination, we performed proteomic analysis of peroxisomes from etiolated Arabidopsis (Arabidopsis thaliana) seedlings. The detection of 77 peroxisomal proteins allowed us to perform comparative analysis with the peroxisomal proteome of green leaves, which revealed a large overlap between these two primary peroxisomal variants. Subcellular targeting analysis by fluorescence microscopy validated around 10 new peroxisomal proteins in Arabidopsis. Mutant analysis suggested the role of the cysteine protease RESPONSE TO DROUGHT21A-LIKE1 in β-oxidation, seed germination, and growth. This work provides a much-needed road map of a major type of plant peroxisome and has established a basis for future investigations of peroxisomal proteolytic processes to understand their roles in development and in plant interaction with the environment.
authors.affiliation: Department of Energy Plant Research Laboratory , Michigan State University, East Lansing, Michigan 48824.
authors.forename: Sheng
authors.initials: S
authors.lastname: Quan
authors.forename: Pingfang
authors.initials: P
authors.lastname: Yang
authors.forename: Gaëlle
authors.initials: G
authors.lastname: Cassin-Ross
authors.forename: Navneet
authors.initials: N
authors.lastname: Kaur
authors.forename: Robert
authors.initials: R
authors.lastname: Switzenberg
authors.forename: Kyaw
authors.initials: K
authors.lastname: Aung
authors.forename: Jiying
authors.initials: J
authors.lastname: Li
authors.forename: Jianping
authors.initials: J
authors.lastname: Hu
mesh_terms: D000595:Amino Acid Sequence; D017360:Arabidopsis / Q000201:enzymology* / Q000254:growth & development* / Q000378:metabolism; D029681:Arabidopsis Proteins / Q000737:chemistry / Q000378:metabolism; D002853:Chromatography, Liquid; D057056:Cysteine Proteases / Q000378:metabolism*; D004252:DNA Mutational Analysis; D004269:DNA, Bacterial / Q000235:genetics; D004591:Electrophoresis, Polyacrylamide Gel; D064527:Etiolation; D020869:Gene Expression Profiling; D018506:Gene Expression Regulation, Plant; D053858:Metabolic Networks and Pathways; D008856:Microscopy, Fluorescence; D008969:Molecular Sequence Data; D009154:Mutation / Q000235:genetics; D010084:Oxidation-Reduction; D020675:Peroxisomes / Q000201:enzymology* / Q000378:metabolism; D020543:Proteome / Q000378:metabolism*; D040901:Proteomics; D015203:Reproducibility of Results; D036226:Seedlings / Q000235:genetics / Q000378:metabolism*; D016415:Sequence Alignment; D013347:Subcellular Fractions / Q000378:metabolism; D053719:Tandem Mass Spectrometry
chemical_list: D029681:Arabidopsis Proteins; D004269:DNA, Bacterial; D020543:Proteome; C036483:T-DNA; D057056:Cysteine Proteases