title: Deficiency of Starch Synthase IIIa and IVb Alters Starch Granule Morphology from Polyhedral to Spherical in Rice Endosperm.
abstract: Starch granule morphology differs markedly among plant species. However, the mechanisms controlling starch granule morphology have not been elucidated. Rice (Oryza sativa) endosperm produces characteristic compound-type granules containing dozens of polyhedral starch granules within an amyloplast. Some other cereal species produce simple-type granules, in which only one starch granule is present per amyloplast. A double mutant rice deficient in the starch synthase (SS) genes SSIIIa and SSIVb (ss3a ss4b) produced spherical starch granules, whereas the parental single mutants produced polyhedral starch granules similar to the wild type. The ss3a ss4b amyloplasts contained compound-type starch granules during early developmental stages, and spherical granules were separated from each other during subsequent amyloplast development and seed dehydration. Analysis of glucan chain length distribution identified overlapping roles for SSIIIa and SSIVb in amylopectin chain synthesis, with a degree of polymerization of 42 or greater. Confocal fluorescence microscopy and immunoelectron microscopy of wild-type developing rice seeds revealed that the majority of SSIVb was localized between starch granules. Therefore, we propose that SSIIIa and SSIVb have crucial roles in determining starch granule morphology and in maintaining the amyloplast envelope structure. We present a model of spherical starch granule production.
authors.affiliation: Department of Biological Production, Akita Prefectural University, Akita City, Akita 010-0195, Japan (Y.T., N.C., Y.N., N.F.);Division of Plant Sciences, National Institute of Agrobiological Sciences, Tsukuba 305-8602, Japan (Y.K.);Institute of Plant Science and Resources, Okayama University, Kurashiki 710-0046, Japan (R.M.);Department of General Education, Yamaguchi Prefectural University, Yamaguchi 753-8502, Japan (M.O.);Plant Genetic Resources, Institute of Genetic Resources, Faculty of Agriculture, Kyushu University, Fukuoka 812-8581, Japan (M.F., T.K.);RIKEN Center for Sustainable Resource Science, Tsurumi-ku, Yokohama 230-0045, Japan (Y.O., M.K., K.S., K.T., M.S.);Graduate School of Pharmaceutical Sciences, Chiba University, Chuo-ku, Chiba 260-8675, Japan (K.S.); andDepartment of Food Science and Human Nutrition, Iowa State University, Ames, Iowa 50011-1120 (Y.A., J.-L.J.).
authors.forename: Yoshiko
authors.initials: Y
authors.lastname: Toyosawa
authors.affiliation: Department of Biological Production, Akita Prefectural University, Akita City, Akita 010-0195, Japan (Y.T., N.C., Y.N., N.F.);Division of Plant Sciences, National Institute of Agrobiological Sciences, Tsukuba 305-8602, Japan (Y.K.);Institute of Plant Science and Resources, Okayama University, Kurashiki 710-0046, Japan (R.M.);Department of General Education, Yamaguchi Prefectural University, Yamaguchi 753-8502, Japan (M.O.);Plant Genetic Resources, Institute of Genetic Resources, Faculty of Agriculture, Kyushu University, Fukuoka 812-8581, Japan (M.F., T.K.);RIKEN Center for Sustainable Resource Science, Tsurumi-ku, Yokohama 230-0045, Japan (Y.O., M.K., K.S., K.T., M.S.);Graduate School of Pharmaceutical Sciences, Chiba University, Chuo-ku, Chiba 260-8675, Japan (K.S.); andDepartment of Food Science and Human Nutrition, Iowa State University, Ames, Iowa 50011-1120 (Y.A., J.-L.J.).
authors.forename: Yasushi
authors.initials: Y
authors.lastname: Kawagoe
authors.affiliation: Department of Biological Production, Akita Prefectural University, Akita City, Akita 010-0195, Japan (Y.T., N.C., Y.N., N.F.);Division of Plant Sciences, National Institute of Agrobiological Sciences, Tsukuba 305-8602, Japan (Y.K.);Institute of Plant Science and Resources, Okayama University, Kurashiki 710-0046, Japan (R.M.);Department of General Education, Yamaguchi Prefectural University, Yamaguchi 753-8502, Japan (M.O.);Plant Genetic Resources, Institute of Genetic Resources, Faculty of Agriculture, Kyushu University, Fukuoka 812-8581, Japan (M.F., T.K.);RIKEN Center for Sustainable Resource Science, Tsurumi-ku, Yokohama 230-0045, Japan (Y.O., M.K., K.S., K.T., M.S.);Graduate School of Pharmaceutical Sciences, Chiba University, Chuo-ku, Chiba 260-8675, Japan (K.S.); andDepartment of Food Science and Human Nutrition, Iowa State University, Ames, Iowa 50011-1120 (Y.A., J.-L.J.).
authors.forename: Ryo
authors.initials: R
authors.lastname: Matsushima
authors.affiliation: Department of Biological Production, Akita Prefectural University, Akita City, Akita 010-0195, Japan (Y.T., N.C., Y.N., N.F.);Division of Plant Sciences, National Institute of Agrobiological Sciences, Tsukuba 305-8602, Japan (Y.K.);Institute of Plant Science and Resources, Okayama University, Kurashiki 710-0046, Japan (R.M.);Department of General Education, Yamaguchi Prefectural University, Yamaguchi 753-8502, Japan (M.O.);Plant Genetic Resources, Institute of Genetic Resources, Faculty of Agriculture, Kyushu University, Fukuoka 812-8581, Japan (M.F., T.K.);RIKEN Center for Sustainable Resource Science, Tsurumi-ku, Yokohama 230-0045, Japan (Y.O., M.K., K.S., K.T., M.S.);Graduate School of Pharmaceutical Sciences, Chiba University, Chuo-ku, Chiba 260-8675, Japan (K.S.); andDepartment of Food Science and Human Nutrition, Iowa State University, Ames, Iowa 50011-1120 (Y.A., J.-L.J.).
authors.forename: Naoko
authors.identifier: http://orcid.org/0000-0002-6792-2232
authors.initials: N
authors.lastname: Crofts
authors.affiliation: Department of Biological Production, Akita Prefectural University, Akita City, Akita 010-0195, Japan (Y.T., N.C., Y.N., N.F.);Division of Plant Sciences, National Institute of Agrobiological Sciences, Tsukuba 305-8602, Japan (Y.K.);Institute of Plant Science and Resources, Okayama University, Kurashiki 710-0046, Japan (R.M.);Department of General Education, Yamaguchi Prefectural University, Yamaguchi 753-8502, Japan (M.O.);Plant Genetic Resources, Institute of Genetic Resources, Faculty of Agriculture, Kyushu University, Fukuoka 812-8581, Japan (M.F., T.K.);RIKEN Center for Sustainable Resource Science, Tsurumi-ku, Yokohama 230-0045, Japan (Y.O., M.K., K.S., K.T., M.S.);Graduate School of Pharmaceutical Sciences, Chiba University, Chuo-ku, Chiba 260-8675, Japan (K.S.); andDepartment of Food Science and Human Nutrition, Iowa State University, Ames, Iowa 50011-1120 (Y.A., J.-L.J.).
authors.forename: Masahiro
authors.initials: M
authors.lastname: Ogawa
authors.affiliation: Department of Biological Production, Akita Prefectural University, Akita City, Akita 010-0195, Japan (Y.T., N.C., Y.N., N.F.);Division of Plant Sciences, National Institute of Agrobiological Sciences, Tsukuba 305-8602, Japan (Y.K.);Institute of Plant Science and Resources, Okayama University, Kurashiki 710-0046, Japan (R.M.);Department of General Education, Yamaguchi Prefectural University, Yamaguchi 753-8502, Japan (M.O.);Plant Genetic Resources, Institute of Genetic Resources, Faculty of Agriculture, Kyushu University, Fukuoka 812-8581, Japan (M.F., T.K.);RIKEN Center for Sustainable Resource Science, Tsurumi-ku, Yokohama 230-0045, Japan (Y.O., M.K., K.S., K.T., M.S.);Graduate School of Pharmaceutical Sciences, Chiba University, Chuo-ku, Chiba 260-8675, Japan (K.S.); andDepartment of Food Science and Human Nutrition, Iowa State University, Ames, Iowa 50011-1120 (Y.A., J.-L.J.).
authors.forename: Masako
authors.initials: M
authors.lastname: Fukuda
authors.affiliation: Department of Biological Production, Akita Prefectural University, Akita City, Akita 010-0195, Japan (Y.T., N.C., Y.N., N.F.);Division of Plant Sciences, National Institute of Agrobiological Sciences, Tsukuba 305-8602, Japan (Y.K.);Institute of Plant Science and Resources, Okayama University, Kurashiki 710-0046, Japan (R.M.);Department of General Education, Yamaguchi Prefectural University, Yamaguchi 753-8502, Japan (M.O.);Plant Genetic Resources, Institute of Genetic Resources, Faculty of Agriculture, Kyushu University, Fukuoka 812-8581, Japan (M.F., T.K.);RIKEN Center for Sustainable Resource Science, Tsurumi-ku, Yokohama 230-0045, Japan (Y.O., M.K., K.S., K.T., M.S.);Graduate School of Pharmaceutical Sciences, Chiba University, Chuo-ku, Chiba 260-8675, Japan (K.S.); andDepartment of Food Science and Human Nutrition, Iowa State University, Ames, Iowa 50011-1120 (Y.A., J.-L.J.).
authors.forename: Toshihiro
authors.initials: T
authors.lastname: Kumamaru
authors.affiliation: Department of Biological Production, Akita Prefectural University, Akita City, Akita 010-0195, Japan (Y.T., N.C., Y.N., N.F.);Division of Plant Sciences, National Institute of Agrobiological Sciences, Tsukuba 305-8602, Japan (Y.K.);Institute of Plant Science and Resources, Okayama University, Kurashiki 710-0046, Japan (R.M.);Department of General Education, Yamaguchi Prefectural University, Yamaguchi 753-8502, Japan (M.O.);Plant Genetic Resources, Institute of Genetic Resources, Faculty of Agriculture, Kyushu University, Fukuoka 812-8581, Japan (M.F., T.K.);RIKEN Center for Sustainable Resource Science, Tsurumi-ku, Yokohama 230-0045, Japan (Y.O., M.K., K.S., K.T., M.S.);Graduate School of Pharmaceutical Sciences, Chiba University, Chuo-ku, Chiba 260-8675, Japan (K.S.); andDepartment of Food Science and Human Nutrition, Iowa State University, Ames, Iowa 50011-1120 (Y.A., J.-L.J.).
authors.forename: Yozo
authors.initials: Y
authors.lastname: Okazaki
authors.affiliation: Department of Biological Production, Akita Prefectural University, Akita City, Akita 010-0195, Japan (Y.T., N.C., Y.N., N.F.);Division of Plant Sciences, National Institute of Agrobiological Sciences, Tsukuba 305-8602, Japan (Y.K.);Institute of Plant Science and Resources, Okayama University, Kurashiki 710-0046, Japan (R.M.);Department of General Education, Yamaguchi Prefectural University, Yamaguchi 753-8502, Japan (M.O.);Plant Genetic Resources, Institute of Genetic Resources, Faculty of Agriculture, Kyushu University, Fukuoka 812-8581, Japan (M.F., T.K.);RIKEN Center for Sustainable Resource Science, Tsurumi-ku, Yokohama 230-0045, Japan (Y.O., M.K., K.S., K.T., M.S.);Graduate School of Pharmaceutical Sciences, Chiba University, Chuo-ku, Chiba 260-8675, Japan (K.S.); andDepartment of Food Science and Human Nutrition, Iowa State University, Ames, Iowa 50011-1120 (Y.A., J.-L.J.).
authors.forename: Miyako
authors.initials: M
authors.lastname: Kusano
authors.affiliation: Department of Biological Production, Akita Prefectural University, Akita City, Akita 010-0195, Japan (Y.T., N.C., Y.N., N.F.);Division of Plant Sciences, National Institute of Agrobiological Sciences, Tsukuba 305-8602, Japan (Y.K.);Institute of Plant Science and Resources, Okayama University, Kurashiki 710-0046, Japan (R.M.);Department of General Education, Yamaguchi Prefectural University, Yamaguchi 753-8502, Japan (M.O.);Plant Genetic Resources, Institute of Genetic Resources, Faculty of Agriculture, Kyushu University, Fukuoka 812-8581, Japan (M.F., T.K.);RIKEN Center for Sustainable Resource Science, Tsurumi-ku, Yokohama 230-0045, Japan (Y.O., M.K., K.S., K.T., M.S.);Graduate School of Pharmaceutical Sciences, Chiba University, Chuo-ku, Chiba 260-8675, Japan (K.S.); andDepartment of Food Science and Human Nutrition, Iowa State University, Ames, Iowa 50011-1120 (Y.A., J.-L.J.).
authors.forename: Kazuki
authors.initials: K
authors.lastname: Saito
authors.affiliation: Department of Biological Production, Akita Prefectural University, Akita City, Akita 010-0195, Japan (Y.T., N.C., Y.N., N.F.);Division of Plant Sciences, National Institute of Agrobiological Sciences, Tsukuba 305-8602, Japan (Y.K.);Institute of Plant Science and Resources, Okayama University, Kurashiki 710-0046, Japan (R.M.);Department of General Education, Yamaguchi Prefectural University, Yamaguchi 753-8502, Japan (M.O.);Plant Genetic Resources, Institute of Genetic Resources, Faculty of Agriculture, Kyushu University, Fukuoka 812-8581, Japan (M.F., T.K.);RIKEN Center for Sustainable Resource Science, Tsurumi-ku, Yokohama 230-0045, Japan (Y.O., M.K., K.S., K.T., M.S.);Graduate School of Pharmaceutical Sciences, Chiba University, Chuo-ku, Chiba 260-8675, Japan (K.S.); andDepartment of Food Science and Human Nutrition, Iowa State University, Ames, Iowa 50011-1120 (Y.A., J.-L.J.).
authors.forename: Kiminori
authors.initials: K
authors.lastname: Toyooka
authors.affiliation: Department of Biological Production, Akita Prefectural University, Akita City, Akita 010-0195, Japan (Y.T., N.C., Y.N., N.F.);Division of Plant Sciences, National Institute of Agrobiological Sciences, Tsukuba 305-8602, Japan (Y.K.);Institute of Plant Science and Resources, Okayama University, Kurashiki 710-0046, Japan (R.M.);Department of General Education, Yamaguchi Prefectural University, Yamaguchi 753-8502, Japan (M.O.);Plant Genetic Resources, Institute of Genetic Resources, Faculty of Agriculture, Kyushu University, Fukuoka 812-8581, Japan (M.F., T.K.);RIKEN Center for Sustainable Resource Science, Tsurumi-ku, Yokohama 230-0045, Japan (Y.O., M.K., K.S., K.T., M.S.);Graduate School of Pharmaceutical Sciences, Chiba University, Chuo-ku, Chiba 260-8675, Japan (K.S.); andDepartment of Food Science and Human Nutrition, Iowa State University, Ames, Iowa 50011-1120 (Y.A., J.-L.J.).
authors.forename: Mayuko
authors.initials: M
authors.lastname: Sato
authors.affiliation: Department of Biological Production, Akita Prefectural University, Akita City, Akita 010-0195, Japan (Y.T., N.C., Y.N., N.F.);Division of Plant Sciences, National Institute of Agrobiological Sciences, Tsukuba 305-8602, Japan (Y.K.);Institute of Plant Science and Resources, Okayama University, Kurashiki 710-0046, Japan (R.M.);Department of General Education, Yamaguchi Prefectural University, Yamaguchi 753-8502, Japan (M.O.);Plant Genetic Resources, Institute of Genetic Resources, Faculty of Agriculture, Kyushu University, Fukuoka 812-8581, Japan (M.F., T.K.);RIKEN Center for Sustainable Resource Science, Tsurumi-ku, Yokohama 230-0045, Japan (Y.O., M.K., K.S., K.T., M.S.);Graduate School of Pharmaceutical Sciences, Chiba University, Chuo-ku, Chiba 260-8675, Japan (K.S.); andDepartment of Food Science and Human Nutrition, Iowa State University, Ames, Iowa 50011-1120 (Y.A., J.-L.J.).
authors.forename: Yongfeng
authors.initials: Y
authors.lastname: Ai
authors.affiliation: Department of Biological Production, Akita Prefectural University, Akita City, Akita 010-0195, Japan (Y.T., N.C., Y.N., N.F.);Division of Plant Sciences, National Institute of Agrobiological Sciences, Tsukuba 305-8602, Japan (Y.K.);Institute of Plant Science and Resources, Okayama University, Kurashiki 710-0046, Japan (R.M.);Department of General Education, Yamaguchi Prefectural University, Yamaguchi 753-8502, Japan (M.O.);Plant Genetic Resources, Institute of Genetic Resources, Faculty of Agriculture, Kyushu University, Fukuoka 812-8581, Japan (M.F., T.K.);RIKEN Center for Sustainable Resource Science, Tsurumi-ku, Yokohama 230-0045, Japan (Y.O., M.K., K.S., K.T., M.S.);Graduate School of Pharmaceutical Sciences, Chiba University, Chuo-ku, Chiba 260-8675, Japan (K.S.); andDepartment of Food Science and Human Nutrition, Iowa State University, Ames, Iowa 50011-1120 (Y.A., J.-L.J.).
authors.forename: Jay-Lin
authors.identifier: http://orcid.org/0000-0002-7570-2774
authors.initials: JL
authors.lastname: Jane
authors.affiliation: Department of Biological Production, Akita Prefectural University, Akita City, Akita 010-0195, Japan (Y.T., N.C., Y.N., N.F.);Division of Plant Sciences, National Institute of Agrobiological Sciences, Tsukuba 305-8602, Japan (Y.K.);Institute of Plant Science and Resources, Okayama University, Kurashiki 710-0046, Japan (R.M.);Department of General Education, Yamaguchi Prefectural University, Yamaguchi 753-8502, Japan (M.O.);Plant Genetic Resources, Institute of Genetic Resources, Faculty of Agriculture, Kyushu University, Fukuoka 812-8581, Japan (M.F., T.K.);RIKEN Center for Sustainable Resource Science, Tsurumi-ku, Yokohama 230-0045, Japan (Y.O., M.K., K.S., K.T., M.S.);Graduate School of Pharmaceutical Sciences, Chiba University, Chuo-ku, Chiba 260-8675, Japan (K.S.); andDepartment of Food Science and Human Nutrition, Iowa State University, Ames, Iowa 50011-1120 (Y.A., J.-L.J.).
authors.forename: Yasunori
authors.identifier: http://orcid.org/0000-0001-7660-0078
authors.initials: Y
authors.lastname: Nakamura
authors.affiliation: Department of Biological Production, Akita Prefectural University, Akita City, Akita 010-0195, Japan (Y.T., N.C., Y.N., N.F.);Division of Plant Sciences, National Institute of Agrobiological Sciences, Tsukuba 305-8602, Japan (Y.K.);Institute of Plant Science and Resources, Okayama University, Kurashiki 710-0046, Japan (R.M.);Department of General Education, Yamaguchi Prefectural University, Yamaguchi 753-8502, Japan (M.O.);Plant Genetic Resources, Institute of Genetic Resources, Faculty of Agriculture, Kyushu University, Fukuoka 812-8581, Japan (M.F., T.K.);RIKEN Center for Sustainable Resource Science, Tsurumi-ku, Yokohama 230-0045, Japan (Y.O., M.K., K.S., K.T., M.S.);Graduate School of Pharmaceutical Sciences, Chiba University, Chuo-ku, Chiba 260-8675, Japan (K.S.); andDepartment of Food Science and Human Nutrition, Iowa State University, Ames, Iowa 50011-1120 (Y.A., J.-L.J.) naokof@akita-pu.ac.jp.
authors.forename: Naoko
authors.initials: N
authors.lastname: Fujita
mesh_terms: D018744:DNA, Plant / Q000235:genetics; D056625:Endosperm / Q000378:metabolism / Q000648:ultrastructure; D050356:Lipid Metabolism; D008855:Microscopy, Electron, Scanning; D046529:Microscopy, Electron, Transmission; D009154:Mutation; D012275:Oryza / Q000235:genetics / Q000378:metabolism*; D010802:Phylogeny; D010940:Plant Proteins / Q000235:genetics / Q000378:metabolism; D030821:Plants, Genetically Modified; D018087:Plastids / Q000378:metabolism / Q000648:ultrastructure; D011994:Recombinant Proteins / Q000235:genetics / Q000378:metabolism; D013213:Starch / Q000737:chemistry / Q000378:metabolism* / Q000648:ultrastructure; D013214:Starch Synthase / Q000172:deficiency* / Q000235:genetics
chemical_list: D018744:DNA, Plant; D010940:Plant Proteins; D011994:Recombinant Proteins; D013213:Starch; D013214:Starch Synthase