Functional Analysis of Arabidopsis AtRBR1 after sucrose starvation

2010 Fiscal Year Final Research Report

• Project/Area Number: 20570042
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Single-year Grants
• Section: 一般
• Research Field: Plant molecular biology/Plant physiology
• Research Institution: Ishikawa Prefectural University
• Principal Investigator: SEKINE Masami Ishikawa Prefectural University, 生物資源環境学部, 准教授 (70226653)
• Project Period (FY): 2008 – 2010
• Keywords: 細胞周期 / シロイヌナズナ / 栄養飢餓 / RNAi

Research Abstract

Although sucrose availability is crucial for commitment to plant cell division during G1 phase by controlling the expression of D-type cyclins, it has remained unclear how these factors mediate entry into the cell cycle. Here we show that Arabidopsis RETINOBLASTOMA-RELATED PROTEIN 1 (AtRBR1) is involved in G1-phase cell cycle arrest caused by sucrose starvation. We generated estrogen-inducible AtRBR1 RNA interference (RNAi) Arabidopsis suspension MM2d cells, and found that downregulation of AtRBR1 leads to a higher frequency of arrest in G2 phase, instead of G1-phase arrest in the uninduced control, after sucrose starvation. Downregulation of AtRBR1 also stimulated the activation of E2F-regulated genes when these genes were repressed in the uninduced cells under the limited sucrose conditions. We conclude that AtRBR1 is a key effector for the ability of sucrose to modulate progression from G1 phase.

Research Products

• [Journal Article] Key Arabidopsis cell cycle proteins undergo proteasome-mediated degradation during sucrose starvation. (2011)
  • Author(s): Hirano, H., Shinmyo, A., Sekine, M.
  • Journal Title: Plant Physiology and Biochemistry 49 Pages: 687-691
• [Journal Article] Cryptogein-induced cell cycle arrest at G2 phase is associated with inhibition of cyclin-dependent kinases, suppression of expression of cell cycle-related genes and protein degradation in synchronized tobacco BY-2 cells. (2011)
  • Author(s): Ohno, R., Kadota, Y., Fujii, S., Sekine, M., Umeda, M., Kuchitsu, K.
  • Journal Title: Plant & Cell Physiology 52 Pages: 922-932
• [Journal Article] Both negative and positive G1 cell cycle regulators undergo proteasome-mediated degradation during sucrose starvation in Arabidopsis.
  • Author(s): Hirano, H., Shinmyo, A., Sekine, M.
  • Journal Title: Plant Signaling & Behavior in press
• [Presentation] Arabidopsis RETINOBLASTOMA-RELATED PROTEIN1 is involved in G1-phase arrest in sucrose starvation. (2010)
  • Author(s): Hirano, H., Shinmyo, A., Sekine, M.
  • Organizer: 21^<st> International Conference on Arabidopsis Research.
  • Place of Presentation: Pacifico Yokohama, Yokohama, Japan
  • Year and Date: 20100606-20100610
• [Book] Plant cyclin-dependent kinase activity using immunoprecipitation coupled kinase assay and baculovirus expression system. Methods in Molecular Biology. Plant Kinases: Methods and Protocols. Edited by N. Dissmeyer and A. Schnittger
  • Author(s): Harashima, H., Sekine, M.
  • Publisher: Humana Press Inc., Totowa, NJ. in press
• [Remarks] ホームページ等
  • URL: http://www.ishikawa-pu.ac.jp/guidance/teacher/bioproduciton/b_sekine.html