Molecular basis of recycling and quality control of chloroplasts by selective autophagy

• Project/Area Number: 15H04626
• Research Category: Grant-in-Aid for Scientific Research (B)
• Allocation Type: Single-year Grants
• Section: 一般
• Research Field: Applied molecular and cellular biology
• Research Institution: Tohoku University
• Principal Investigator: Ishida Hiroyuki 東北大学, 農学研究科, 准教授 (60312625)
• Co-Investigator(Kenkyū-buntansha): 牧野 周 東北大学, 農学研究科, 教授 (70181617)
• Research Collaborator: IZUMI Masanori ; WADA Shinya ; EGUCHI Masatake ; HIROTA Takaaki ; YOKOHAMA Ryo ; NISHIMURA Tsubasa ; NAKAMURA Sakuya ; ISHIDA Hiromi
• Project Period (FY): 2015-04-01 – 2019-03-31
• Project Status: Completed (Fiscal Year 2018)
• Budget Amount: ¥15,990,000 (Direct Cost: ¥12,300,000、Indirect Cost: ¥3,690,000); Fiscal Year 2018: ¥3,120,000 (Direct Cost: ¥2,400,000、Indirect Cost: ¥720,000); Fiscal Year 2017: ¥3,510,000 (Direct Cost: ¥2,700,000、Indirect Cost: ¥810,000); Fiscal Year 2016: ¥3,510,000 (Direct Cost: ¥2,700,000、Indirect Cost: ¥810,000); Fiscal Year 2015: ¥5,850,000 (Direct Cost: ¥4,500,000、Indirect Cost: ¥1,350,000)
• Keywords: オートファジー / 葉緑体 / シロイヌナズナ / 栄養リサイクル / オルガネラ / 葉の老化 / 老化

Outline of Final Research Achievements

We aimed to reveal molecular mechanisms of selective autophagy of chloroplasts and obtained following results. (1) We revealed roles of known ATG8-interacting proteins, NBR1, ATG11, and ATI1/2 on the RCB (Rubisco-containing body) pathway and chlorophagy (whole-chloroplast autophagy). (2) We isolated novel mutants having abnormality on the RCB pathway. (3) We searched novel autophagy receptors which may act for chloroplast by co-immunoprecipitation and LC-MS/MS analysis.

Academic Significance and Societal Importance of the Research Achievements

植物に特有のオルガネラである葉緑体に注目することで、選択的オートファジーのメカニズムについて酵母や動物では得られない基礎的知見を提供した。オートファジーによる葉緑体のリサイクルや品質管理機構は、必須栄養素の体内転流、光合成、バイオマスや有用物質生産などと密接にかかわっている。その分子機構の一端を解明したことは、今後の作物の生産性や品質の向上を目指す農学研究の展開に向けても意義深い。

Research Products

• [Int'l Joint Research] コーネル大学(米国)
• [Int'l Joint Research] コーネル大学(米国)
• [Journal Article] An additional role for chloroplast proteins?an amino acid reservoir for energy production during sugar starvation (2018)
  • Author(s): Izumi Masanori、Ishida Hiroyuki
  • Journal Title: Plant Signaling & Behavior Volume: 14 Issue: 1 Pages: 1552057-1552057
  • DOI: 10.1080/15592324.2018.1552057
  • Peer Reviewed
• [Journal Article] Autophagic protein degradation provides substrates to amino acid catabolic pathways as an adaptive response to sugar starvation in Arabidopsis (2018)
  • Author(s): Hirota, T., Izumi, M., Wada, S., Makino, A., Ishida, H.
  • Journal Title: Plant Cell Physiol. Volume: （印刷中） Pages: 1363-1376
  • DOI: 10.1093/pcp/pcy005
  • Peer Reviewed
• [Journal Article] Impacts of autophagy on nitrogen use efficiency in plants (2018)
  • Author(s): Ishida, H., Makino, A
  • Journal Title: Soil Sci. Plant Nutr. Volume: 64 Issue: 1 Pages: 100-105
  • DOI: 10.1080/00380768.2017.1412239
  • NAID: 210000011955
  • Peer Reviewed
• [Journal Article] Autophagy is induced under Zn limitation and contributes to Zn-limited stress tolerance in Arabidopsis (Arabidopsis thaliana) (2017)
  • Author(s): Eguchi, M., Kimura, K., Makino, A., Ishida, H.
  • Journal Title: Soil Sci. Plant Nutr. Volume: 63 Issue: 4 Pages: 342-350
  • DOI: 10.1080/00380768.2017.1360750
  • NAID: 210000011915
  • Peer Reviewed
• [Presentation] GFS9はシロイヌナズナの暗所芽生えにおけるプラスチドのピースミールオートファジーに関与する (2019)
  • Author(s): 石田宏幸, 石田 ひろみ, 泉 正範, 林 誠, 牧野 周, Klaas van Wijk
  • Organizer: 日本植物生理学会
• [Presentation] シロイヌナズナにおける亜鉛栄養制限下でのオートファジーの誘導とストレス耐性への寄与 (2018)
  • Author(s): 江口雅丈, 木村和彦, 牧野 周, 石田宏幸
  • Organizer: 日本分子生物学会
  • Invited
• [Presentation] 植物の栄養リサイクルとオートファジー (2018)
  • Author(s): 石田宏幸
  • Organizer: 第34回ユーグレナ研究会
  • Invited
• [Presentation] Autophagy provides substrates to amino acid catabolic pathways as an adaptive response to sugar starvation in Arabidopsis (2016)
  • Author(s): Ishida, H.
  • Organizer: The 17th International Congress on Photosynthesis Research
  • Place of Presentation: MECC Maastricht, マーストリヒト、オランダ
  • Year and Date: 2016-08-07
  • Int'l Joint Research / Invited
• [Presentation] Autophagy of chloroplasts as an adaptive response to sugar starvation in Arabidopsis (2016)
  • Author(s): Ishida, H.
  • Organizer: International Conference on Arabidopsis
  • Place of Presentation: HICO, 慶州, 韓国
  • Year and Date: 2016-06-29
  • Int'l Joint Research / Invited
• [Presentation] Chloroplast autophagy as an adaptive response to sugar starvation in Arabidopsis (2016)
  • Author(s): Hirota, T., Izumi, M., Wada, S., Makino, A., Ishida, H.
  • Organizer: Gordon Research Conference ‘Mitochondria and Chloroplasts’
  • Place of Presentation: Mt Snow Hotel, バーモント、USA
  • Year and Date: 2016-06-19
  • Int'l Joint Research