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Journal of Plant Biology

, Volume 51, Issue 1, pp 1–10 | Cite as

The HSP90-SGT1-RAR1 molecular chaperone complex: A core modulator in plant immunity

  • Young-Su Seo
  • Sang-Kyu Lee
  • Min-Young Song
  • Jung-Pil Suh
  • Tae-Ryong Hahn
  • Pamela Ronald
  • Jong-Seong Jeon
Review

Abstract

The HSP90 (heat shock protein 90), SGT1 (suppressor of G-two allele ofSkp1), and RAR1 (required forMla12 resistance) proteins in plants form a molecular chaperone complex which is involved in diverse biological signaling including development and disease resistance. The three components of this complex interact via specific protein binding motifs and recruit client proteins to initiate a specific signaling cascade in response to cellular or environmental cues. Although the functions of this chaperone complex during development/growth have not been well characterized, the HSP90 chaperone and SGT1 and RAR1 co-chaperones have been demonstrated to be essential signaling components of plant immune responses. These three proteins also play important roles in activation of the mammalian Nod genes, which possess a structurally conserved plant resistance (R) protein motif, NB-LRR (nucleotide binding site-leucine rich repeat). In this review, we summarize the structures and functions of these molecular chaperones, and discuss their putative modes of action in plant immune responses.

Keywords

Chaperone HSP90 plant immunity RAR1 SGT1 

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Copyright information

© The Botanical Society of Korea 2008

Authors and Affiliations

  • Young-Su Seo
    • 1
  • Sang-Kyu Lee
    • 2
  • Min-Young Song
    • 2
  • Jung-Pil Suh
    • 3
  • Tae-Ryong Hahn
    • 2
  • Pamela Ronald
    • 1
  • Jong-Seong Jeon
    • 2
  1. 1.Department of Plant PathologyUniversity of CaliforniaDavisUSA
  2. 2.Plant Metabolism Research Center & Graduate School of BiotechnologyKyung Hee UniversityYonginKorea
  3. 3.IRRI-KOREA Office (IKO), National Institute of Crop ScienceRural Development AdministrationSuwonKorea

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