title: Sucrose Production Mediated by Lipid Metabolism Suppresses the Physical Interaction of Peroxisomes and Oil Bodies during Germination of Arabidopsis thaliana.
abstract: Physical interaction between organelles is a flexible event and essential for cells to adapt rapidly to environmental stimuli. Germinating plants utilize oil bodies and peroxisomes to mobilize storage lipids for the generation of sucrose as the main energy source. Although membrane interaction between oil bodies and peroxisomes has been widely observed, its underlying molecular mechanism is largely unknown. Here we present genetic evidence for control of the physical interaction between oil bodies and peroxisomes. We identified alleles of the sdp1 mutant altered in oil body morphology. This mutant accumulates bigger and more oil body aggregates compared with the wild type and showed defects in lipid mobilization during germination. SUGAR DEPENDENT 1 (SDP1) encodes major triacylglycerol lipase in Arabidopsis Interestingly, sdp1 seedlings show enhanced physical interaction between oil bodies and peroxisomes compared with the wild type, whereas exogenous sucrose supplementation greatly suppresses the interaction. The same phenomenon occurs in the peroxisomal defective 1 (ped1) mutant, defective in lipid mobilization because of impaired peroxisomal β-oxidation, indicating that sucrose production is a key factor for oil body-peroxisomal dissociation. Peroxisomal dissociation and subsequent release from oil bodies is dependent on actin filaments. We also show that a peroxisomal ATP binding cassette transporter, PED3, is the potential anchor protein to the membranes of these organelles. Our results provide novel components linking lipid metabolism and oil body-peroxisome interaction whereby sucrose may act as a negative signal for the interaction of oil bodies and peroxisomes to fine-tune lipolysis.
authors.affiliation: From the Department of Cell Biology, National Institute for Basic Biology, Myodaiji-cho, Okazaki 444-8585, Japan, the Department of Basic Biology, School of Life Science, SOKENDAI (Graduate University for Advanced Studies), Myodaiji-cho, Okazaki 444-8585, Japan, the RIKEN Center for Sustainable Resource Science, RIKEN, 1-7-22 Suehiro-cho, Tsurumi-ku, Yokohama 230-0045, Japan, the Graduate School of Biological Science, Nara Institute of Science and Technology, 8916-5 Takayama, Ikoma, Nara 630-0192, Japan, and.
authors.forename: Songkui
authors.identifier: 0000-0001-7777-6681
authors.initials: S
authors.lastname: Cui
authors.affiliation: the Graduate School of Science and Technology, Niigata University, 8050 Ikarashi, Ninotyou, Niigata 950-2181, Japan.
authors.forename: Yasuko
authors.initials: Y
authors.lastname: Hayashi
authors.affiliation: the Graduate School of Science and Technology, Niigata University, 8050 Ikarashi, Ninotyou, Niigata 950-2181, Japan.
authors.forename: Masayoshi
authors.initials: M
authors.lastname: Otomo
authors.affiliation: From the Department of Cell Biology, National Institute for Basic Biology, Myodaiji-cho, Okazaki 444-8585, Japan, the Department of Basic Biology, School of Life Science, SOKENDAI (Graduate University for Advanced Studies), Myodaiji-cho, Okazaki 444-8585, Japan, the Laboratory of Biological Diversity, Department of Evolutionary Biology and Biodiversity, National Institute for Basic Biology, Myodaiji-cho, Okazaki 444-8585, Japan.
authors.forename: Shoji
authors.initials: S
authors.lastname: Mano
authors.affiliation: the Department of Applied Biological Chemistry, Faculty of Agriculture, Niigata University, Niigata 950-2181, Japan.
authors.forename: Kazusato
authors.initials: K
authors.lastname: Oikawa
authors.affiliation: the Department of Bioscience, Nagahama Institute of Bio-Science and Technology, 1266 Tamura-Cho, Nagahama 526-0829, Japan.
authors.forename: Makoto
authors.initials: M
authors.lastname: Hayashi
authors.affiliation: From the Department of Cell Biology, National Institute for Basic Biology, Myodaiji-cho, Okazaki 444-8585, Japan, mikosome@nibb.ac.jp.
authors.forename: Mikio
authors.initials: M
authors.lastname: Nishimura
mesh_terms: D018528:ATP-Binding Cassette Transporters / Q000235:genetics / Q000378:metabolism; D000251:Adenosine Triphosphatases; D017360:Arabidopsis / Q000502:physiology*; D029681:Arabidopsis Proteins / Q000235:genetics / Q000378:metabolism; D002265:Carboxylic Ester Hydrolases / Q000235:genetics / Q000378:metabolism; D018525:Germination / Q000502:physiology*; D066292:Lipid Droplets / Q000378:metabolism*; D050356:Lipid Metabolism / Q000502:physiology*; D020675:Peroxisomes / Q000235:genetics / Q000378:metabolism*; D013395:Sucrose / Q000378:metabolism*
chemical_list: D018528:ATP-Binding Cassette Transporters; D029681:Arabidopsis Proteins; D013395:Sucrose; D002265:Carboxylic Ester Hydrolases; C510423:SDP1 protein, Arabidopsis; D000251:Adenosine Triphosphatases; C456843:At4g39850 protein, Arabidopsis
keywords: ABC transporter; lipid droplet; lipolysis; membrane; oil body; organelle; peroxisome; sucrose production