Centers & Labs

RIKEN Center for Sustainable Resource Science

Plant Productivity Systems Research Group

Group Director: Hitoshi Sakakibara (D.Agr.)
Hitoshi  Sakakibara(D.Agr.)

Our group will conduct studies on uptake and signaling of nitrogen, action mechanisms of phytohormones, and mechanisms of metal tolerance and accumulation to aim for development of innovation technology for low-input production of plants by saving nitrogen and water, and recovery and recycling of metals. We will also conduct studies for discovery of novel signaling molecules and key genes for plant productivity by using hormonome platform.

Main Research Field


Related Research Fields

Chemistry / Agricultural sciences


  • Molecular Plant Physiology
  • Nitrogen Nutrition
  • Plant Productivity
  • Plant hormones

Selected Publications

  1. Osugi, T., Kojima, M., Takebayashi, Y., Ueda, N., Kiba, T. and Sakakibara, H.
    "Systemic transport of trans-zeatin and its precursor have differing roles in shoots of Arabidopsis"
    Nature Plants 3: 17112 (2017)
  2. Kiba, T., Takei, K., Kojima, M. and Sakakibara, H.:
    "Side-chain modification of cytokinins control shoot growth in Arabidopsis"
    Dev. Cell 27, 452-461 (2013).
  3. Kiba, T., Feria-Bourrellier, A.-B., Lafouge, F., Lezhneva, L., Boutet-Mercey, S., Orsel, M., Bréhaut, V., Miller, A., Daniel-Vedele, F., Sakakibara, H. and Krapp, A.:
    "The Arabidopsis nitrate transporter NRT2.4 plays a double role in roots and shoots of nitrogen-starved plants "
    Plant Cell 24, 245-258 (2012).
  4. Nakamichi, N., Kiba, T., Henriques, R., Mizuno, T., Chua, N.-H. and Sakakibara, H.:
    "PSEUDO-RESPONSE REGULATORS 9, 7 and 5 are transcriptional repressors in the Arabidopsis circadian clock"
    Plant Cell 22, 594-605 (2010).
  5. Kuroha, T., Tokunaga, H., Kojima, M., Ueda, N., Ishida, T., Nagawa, S., Fukuda, H., Sugimoto, K. and Sakakibara, H.:
    "Functional analyses of LONELY GUY cytokinin-activating enzymes reveal the importance of the direct activation pathway in Arabidopsis"
    Plant Cell 21, 3152-3169 (2009).
  6. Kojima, M., Kamada-Nobusada, T., Komatsu, H., Takei, K., Kuroha, T., Mizutani, M., Ashikari, M., Ueguchi-Tanaka, M., Matsuoka, M., Suzuki, K. and Sakakibara, H.:
    "Highly-sensitive and high-throughput analysis of plant hormones using MS-probe modification and liquid chromatography-tandem mass spectrometry: an application for hormone profiling in Oryza sativa "
    Plant Cell Physiol. 50, 1201-1214 (2009).
  7. Sugawara, H., Ueda, N., Kojima, M., Makita, N., Yamaya, T. and Sakakibara, H.:
    "Structural insight into the reaction mechanism and evolution of cytokinin biosynthesis"
    Proc. Natl. Acad. Sci. U.S.A. 105, 2734-2739 (2008).
  8. Kurakawa, T., Ueda, N., Maekawa, M., Kobayashi, K., Kojima, M., Nagato, Y., Sakakibara, H. and Kyozuka, J.:
    "Direct control of shoot meristem activity by a cytokinin activating enzyme"
    Nature 445, 652-655 (2007).
  9. Sakakibara, H.:
    "Cytokinins: Activity, biosynthesis and translocation"
    Annu. Rev. Plant Biol. 57, 431-449 (2006).
  10. Sakakibara, H., Kasahara, H., Ueda, N., Kojima, M., Takei, K., Hishiyama, S., Asami, T., Okada, K., Kamiya, Y., Yamaya, T., and Yamaguchi, S.
    "Agrobacterium tumefaciens increases cytokinin production in plastids by modifying the biosynthetic pathway in the host plant"
    Proc. Natl. Acad. Sci. U.S.A. 102, 9972-9977 (2005).

Lab Members

Principal Investigator

Hitoshi Sakakibara
Group Director

Core Members

Misao Itouga
Senior Research Scientist
Takatoshi Kiba
Research Scientist
Mikiko Kojima
Technical Scientist
Toshihisa Nomura
Postdoctoral Researcher
Nanae Mori
Technical Staff I
Yumiko Takebayashi
Technical Staff I
Erika Toda
Technical Staff I
Jun Inaba
Technical Staff II

Contact information

E712 East Research Building
1-7-22 Suehiro-cho, Tsurumi-ku, Yokohama, Kanagawa 230-0045, Japan

Email: sakaki [at]

Related links

Recent research results

January 17, 2018: Press Release
Clean and green: a moss that removes lead (Pb) from water
February 24, 2017: RIKEN RESEARCH
Getting to the root of nitrite toxicity
January 13, 2017: RIKEN RESEARCH
Precise gene editing in mosses
June 10, 2016: RIKEN RESEARCH
Super-sized plants by tweaking just one gene