title: Defining the dynamin-based ring organizing center on the peroxisome-dividing machinery isolated fromCyanidioschyzon merolae.
abstract: Organelle division is executed through contraction of a ring-shaped supramolecular dividing machinery. A core component of the machinery is the dynamin-based ring conserved during the division of mitochondrion, plastid and peroxisome. Here, using isolated peroxisome-dividing (POD) machinery from a unicellular red algae,Cyanidioschyzon merolae, we identified a dynamin-based ring organizing center (DOC) that acts as an initiation point for formation of the dynamin-based ring.C. merolaecontains a single peroxisome, the division of which can be highly synchronized by light-dark stimulation; thus, intact POD machinery can be isolated in bulk. Dynamin-based ring homeostasis is maintained by the turnover of the GTP-bound form of the dynamin-related protein Dnm1 between the cytosol and division machinery via the DOC. A single DOC is formed on the POD machinery with a diameter of 500-700 nm, and the dynamin-based ring is unidirectionally elongated from the DOC in a manner that is dependent on GTP concentration. During the later step of membrane fission, the second DOC is formed and constructs the double dynamin-based ring to make the machinery thicker. These findings provide new insights to define fundamental mechanisms underlying the dynamin-based membrane fission in eukaryotic cells.
authors.affiliation: Medical Institute of Bioregulation, Kyushu University, 3-1-1 Maidashi, Higashi-ku, Fukuoka 812-8582, Japan.
authors.forename: Yuuta
authors.initials: Y
authors.lastname: Imoto
authors.affiliation: Medical Institute of Bioregulation, Kyushu University, 3-1-1 Maidashi, Higashi-ku, Fukuoka 812-8582, Japan.
authors.forename: Yuichi
authors.initials: Y
authors.lastname: Abe
authors.affiliation: Department of Biology, Faculty of Sciences, Kyushu University, 744 Motooka Nishi-ku, Fukuoka 819-0395, Japan.
authors.forename: Kanji
authors.initials: K
authors.lastname: Okumoto
authors.affiliation: Medical Institute of Bioregulation, Kyushu University, 3-1-1 Maidashi, Higashi-ku, Fukuoka 812-8582, Japan.
authors.forename: Masanori
authors.initials: M
authors.lastname: Honsho
authors.affiliation: Department of Chemical and Biological Science, Faculty of Science, Japan Women's University, 2-8-1 Mejirodai, Bunkyo-ku, Tokyo 112-8681, Japan.|Core Research for Evolutional Science and Technology, Japan Science and Technology Agency, Gobancho, Chiyoda-ku, Tokyo 102-0076, Japan.
authors.forename: Haruko
authors.initials: H
authors.lastname: Kuroiwa
authors.affiliation: Department of Chemical and Biological Science, Faculty of Science, Japan Women's University, 2-8-1 Mejirodai, Bunkyo-ku, Tokyo 112-8681, Japan.|Core Research for Evolutional Science and Technology, Japan Science and Technology Agency, Gobancho, Chiyoda-ku, Tokyo 102-0076, Japan.
authors.forename: Tsuneyoshi
authors.initials: T
authors.lastname: Kuroiwa
authors.affiliation: Medical Institute of Bioregulation, Kyushu University, 3-1-1 Maidashi, Higashi-ku, Fukuoka 812-8582, Japan yfujiki@kyudai.jp.
authors.forename: Yukio
authors.identifier: 0000-0002-8138-6376
authors.initials: Y
authors.lastname: Fujiki
mesh_terms: D020418:Algal Proteins / Q000378:metabolism*; D001681:Biological Assay; D002453:Cell Cycle; D003600:Cytosol / Q000378:metabolism; D034281:Dynamins / Q000378:metabolism*; D006160:Guanosine Triphosphate / Q000378:metabolism; D008954:Models, Biological; D020675:Peroxisomes / Q000378:metabolism*; D000461:Rhodophyta / Q000378:metabolism*
chemical_list: D020418:Algal Proteins; D006160:Guanosine Triphosphate; D034281:Dynamins
keywords: 
  Organelle-dividing machinery; DOC; Dnm1; Dynamin-based ring; GTP; Peroxisome