Cell Stress and Chaperones

, Volume 14, Issue 3, pp 233–243

Characterization of orchardgrass p23, a flowering plant Hsp90 cohort protein

  • Joon-Yung Cha
  • Netty Ermawati
  • Min Hee Jung
  • Mukhamad Su’udi
  • Ki-Yong Kim
  • Jae-Yean Kim
  • Chang-deok Han
  • Kon Ho Lee
  • Daeyoung Son
Original Paper

DOI: 10.1007/s12192-008-0077-6

Cite this article as:
Cha, JY., Ermawati, N., Jung, M.H. et al. Cell Stress and Chaperones (2009) 14: 233. doi:10.1007/s12192-008-0077-6
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Abstract

p23 is a heat shock protein 90 (Hsp90) co-chaperone and stabilizes the Hsp90 heterocomplex in mammals and yeast. In this study, we isolated a complementary DNA (cDNA) encoding p23 from orchardgrass (Dgp23) and characterized its functional roles under conditions of thermal stress. Dgp23 is a 911 bp cDNA with an open reading frame predicted to encode a 180 amino acid protein. Northern analysis showed that expression of Dgp23 transcripts was heat inducible. Dgp23 has a well-conserved p23 domain and interacted with an orchardgrass Hsp90 homolog in vivo, like mammalian and yeast p23 homologs. Recombinant Dgp23 is a small acidic protein with a molecular mass of approximately 27 kDa and pI 4.3. Dgp23 was also shown to function as a chaperone protein by suppression of malate dehydrogenase thermal aggregation. Differential scanning calorimetry thermograms indicated that Dgp23 is a heat-stable protein, capable of increasing the Tm of lysozyme. Moreover, overexpression of Dgp23 in a yeast p23 homolog deletion strain, Δsba1, increased cell viability. These results suggest that Dgp23 plays a role in thermal stress-tolerance and functions as a co-chaperone of Hsp90 and as a chaperone.

Keywords

ChaperoneCo-chaperoneHsp90p23OrchardgrassHeat stressThermotolerance

Copyright information

© Cell Stress Society International 2008

Authors and Affiliations

  • Joon-Yung Cha
    • 1
    • 2
  • Netty Ermawati
    • 1
    • 2
  • Min Hee Jung
    • 1
    • 2
  • Mukhamad Su’udi
    • 1
    • 2
  • Ki-Yong Kim
    • 3
  • Jae-Yean Kim
    • 1
    • 2
  • Chang-deok Han
    • 1
    • 2
  • Kon Ho Lee
    • 1
    • 2
  • Daeyoung Son
    • 1
    • 2
  1. 1.Division of Applied Life Science (BK21 Program), Environmental Biotechnology National Core Research CenterGyeongsang National UniversityJinjuSouth Korea
  2. 2.Plant Molecular Biology and Biotechnology Research CenterGyeongsang National UniversityJinjuSouth Korea
  3. 3.National Institute of Animal Science, RDACheonanSouth Korea