title: OsATG7 is required for autophagy-dependent lipid metabolism in rice postmeiotic anther development.
abstract: In flowering plants, the tapetum, the innermost layer of the anther, provides both nutrient and lipid components to developing microspores, pollen grains, and the pollen coat. Though the programmed cell death of the tapetum is one of the most critical and sensitive steps for fertility and is affected by various environmental stresses, its regulatory mechanisms remain mostly unknown. Here we show that autophagy is required for the metabolic regulation and nutrient supply in anthers and that autophagic degradation within tapetum cells is essential for postmeiotic anther development in rice. Autophagosome-like structures and several vacuole-enclosed lipid bodies were observed in postmeiotic tapetum cells specifically at the uninucleate stage during pollen development, which were completely abolished in a retrotransposon-insertional OsATG7 (autophagy-related 7)-knockout mutant defective in autophagy, suggesting that autophagy is induced in tapetum cells. Surprisingly, the mutant showed complete sporophytic male sterility, failed to accumulate lipidic and starch components in pollen grains at the flowering stage, showed reduced pollen germination activity, and had limited anther dehiscence. Lipidomic analyses suggested impairment of editing of phosphatidylcholines and lipid desaturation in the mutant during pollen maturation. These results indicate a critical involvement of autophagy in a reproductive developmental process of rice, and shed light on the novel autophagy-mediated regulation of lipid metabolism in eukaryotic cells.
authors.affiliation: Department of Applied Biological Science; Tokyo University of Science; Noda, Chiba Japan; Research Institute for Science and Technology; Tokyo University of Science; Noda, Chiba Japan; School of Bioscience and Biotechnology; Tokyo University of Technology; Hachioji, Tokyo Japan.
authors.forename: Takamitsu
authors.initials: T
authors.lastname: Kurusu
authors.affiliation: Department of Applied Biological Science; Tokyo University of Science; Noda, Chiba Japan.
authors.forename: Tomoko
authors.initials: T
authors.lastname: Koyano
authors.affiliation: Department of Applied Biological Science; Tokyo University of Science; Noda, Chiba Japan.
authors.forename: Shigeru
authors.initials: S
authors.lastname: Hanamata
authors.affiliation: Plant Genetics Laboratory; National Institute of Genetics; Mishima, Shizuoka Japan.
authors.forename: Takahiko
authors.initials: T
authors.lastname: Kubo
authors.affiliation: Department of Applied Biological Science; Tokyo University of Science; Noda, Chiba Japan.
authors.forename: Yuhei
authors.initials: Y
authors.lastname: Noguchi
authors.affiliation: Department of Applied Biological Science; Tokyo University of Science; Noda, Chiba Japan.
authors.forename: Chikako
authors.initials: C
authors.lastname: Yagi
authors.affiliation: Department of Chemical Biological Science; Faculty of Science; Japan Women's University; Bunkyo-ku, Tokyo Japan.
authors.forename: Noriko
authors.initials: N
authors.lastname: Nagata
authors.affiliation: Department of Applied Biological Science; Tokyo University of Science; Noda, Chiba Japan.
authors.forename: Takashi
authors.initials: T
authors.lastname: Yamamoto
authors.affiliation: Faculty of Bioscience; Nagahama Institute of Bio-Science and Technology; Shiga, Japan.
authors.forename: Takayuki
authors.initials: T
authors.lastname: Ohnishi
authors.affiliation: Metabolomic Function Research Group; RIKEN Center for Sustainable Resource Science; Yokohama, Kanagawa Japan.
authors.forename: Yozo
authors.initials: Y
authors.lastname: Okazaki
authors.affiliation: Department of Applied Biological Science; Tokyo University of Science; Noda, Chiba Japan.
authors.forename: Nobutaka
authors.initials: N
authors.lastname: Kitahata
authors.affiliation: Department of Applied Biological Science; Tokyo University of Science; Noda, Chiba Japan.
authors.forename: Daichi
authors.initials: D
authors.lastname: Ando
authors.affiliation: Environmental Stress Research Unit; Division of Plant Sciences; National Institute of Agrobiological Sciences; Tsukuba, Ibaraki Japan.
authors.forename: Masaya
authors.initials: M
authors.lastname: Ishikawa
authors.affiliation: Department of Applied Plant Science; Graduate School of Agricultural Sciences; Tohoku University; Sendai, Miyagi, Japan.
authors.forename: Shinya
authors.initials: S
authors.lastname: Wada
authors.affiliation: Agrogenomics Research Center; National Institute of Agrobiological Sciences; Tsukuba, Ibaraki Japan.
authors.forename: Akio
authors.initials: A
authors.lastname: Miyao
authors.affiliation: Agrogenomics Research Center; National Institute of Agrobiological Sciences; Tsukuba, Ibaraki Japan.
authors.forename: Hirohiko
authors.initials: H
authors.lastname: Hirochika
authors.affiliation: Research Institute for Science and Technology; Tokyo University of Science; Noda, Chiba Japan; Department of Biological Science and Technology; Tokyo University of Science; Katsushika, Tokyo Japan.
authors.forename: Hiroaki
authors.initials: H
authors.lastname: Shimada
authors.affiliation: Department of Applied Plant Science; Graduate School of Agricultural Sciences; Tohoku University; Sendai, Miyagi, Japan.
authors.forename: Amane
authors.initials: A
authors.lastname: Makino
authors.affiliation: Metabolomic Function Research Group; RIKEN Center for Sustainable Resource Science; Yokohama, Kanagawa Japan; Graduate School of Pharmaceutical Sciences; Chiba University; Chiba, Chiba Japan.
authors.forename: Kazuki
authors.initials: K
authors.lastname: Saito
authors.affiliation: Department of Applied Plant Science; Graduate School of Agricultural Sciences; Tohoku University; Sendai, Miyagi, Japan.
authors.forename: Hiroyuki
authors.initials: H
authors.lastname: Ishida
authors.affiliation: Faculty of Bioscience; Nagahama Institute of Bio-Science and Technology; Shiga, Japan.
authors.forename: Tetsu
authors.initials: T
authors.lastname: Kinoshita
authors.affiliation: Plant Genetics Laboratory; National Institute of Genetics; Mishima, Shizuoka Japan.
authors.forename: Nori
authors.initials: N
authors.lastname: Kurata
authors.affiliation: Department of Applied Biological Science; Tokyo University of Science; Noda, Chiba Japan; Research Institute for Science and Technology; Tokyo University of Science; Noda, Chiba Japan.
authors.forename: Kazuyuki
authors.initials: K
authors.lastname: Kuchitsu
mesh_terms: D001343:Autophagy / Q000235:genetics*; D035264:Flowers / Q000235:genetics / Q000254:growth & development* / Q000378:metabolism; D050356:Lipid Metabolism / Q000235:genetics*; D008540:Meiosis / Q000235:genetics; D012275:Oryza / Q000235:genetics / Q000254:growth & development / Q000378:metabolism; D010940:Plant Proteins / Q000502:physiology*; D030821:Plants, Genetically Modified; D011058:Pollen / Q000235:genetics / Q000378:metabolism; D044764:Ubiquitin-Activating Enzymes / Q000502:physiology*
chemical_list: D010940:Plant Proteins; D044764:Ubiquitin-Activating Enzymes
keywords: anther; autophagy; male sterility; pollen development; rice