Structural and functional differences of cytosolic 90-kDa heat-shock proteins (Hsp90s) in Arabidopsis thaliana

Structural and functional differences of cytosolic 90-kDa heat-shock proteins (Hsp90s) in Arabidopsis thaliana

Copyright © 2013 The Authors. Published by Elsevier Masson SAS.. All rights reserved.

Bibliographische Detailangaben
Veröffentlicht in:Plant physiology and biochemistry : PPB. - 1991. - 70(2013) vom: 23. Sept., Seite 368-73
1. Verfasser: Cha, Joon-Yung (VerfasserIn)
Weitere Verfasser: Ahn, Gyeongik, Kim, Joo Yeon, Kang, Sun Bin, Kim, Mi Ri, Su'udi, Mukhamad, Kim, Woe-Yeon, Son, Daeyoung
Format: Online-Aufsatz
Sprache:English
Veröffentlicht: 2013
Zugriff auf das übergeordnete Werk:Plant physiology and biochemistry : PPB
Schlagworte:Comparative Study Journal Article Research Support, Non-U.S. Gov't Arabidopsis thaliana Chaperone Cytoplasm G6PDH HS Heat shock protein 90 Hsps mehr... MDH Oligomerization SEC glucose-6-phosphate dehydrogenase heat shock heat shock proteins malate dehydrogenase size-exclusion chromatography Arabidopsis Proteins HSP90 Heat-Shock Proteins Molecular Chaperones Adenosine Triphosphate 8L70Q75FXE
Beschreibung
Zusammenfassung:Copyright © 2013 The Authors. Published by Elsevier Masson SAS.. All rights reserved.
The seven members of the 90-kDa heat shock protein (Hsp90) family encode highly conserved molecular chaperones essential for cell survival in Arabidopsis thaliana. Hsp90 are abundant proteins, localized in different compartments with AtHsp90.1-4 in the cytosol and AtHsp90.5-7 in different organelles. Among the AtHsp90, AtHsp90.1, is stress-inducible and shares comparatively low sequence identity with the constitutively expressed AtHsp90.2-4. Even though abundant information is available on mammalian cytosolic Hsp90 proteins, it is unknown whether cytosolic Hsp90 proteins display different structural and functional properties. We have now analyzed two A. thalianas cytosolic Hsp90s, AtHsp90.1 and AtHsp90.3, for functional divergence. AtHsp90.3 showed higher holdase chaperone activity than AtHsp90.1, although both AtHsp90s exhibited effective chaperone activity. Size-exclusion chromatography revealed different oligomeric states distinguishing the two Hsp90 proteins. While AtHsp90.1 exists in several oligomeric states, including monomers, dimers and higher oligomers, AtHsp90.3 exists predominantly in a high oligomeric state. High oligomeric state of AtHsp90.1 showed higher holdase chaperone activity than the respective monomer or dimer states. When high oligomeric forms of AtHsp90.1 and AtHsp90.3 are reduced by DTT, activity was reduced compared to that found in the native high oligomeric state. In addition, ATP-dependent foldase chaperone activity of AtHsp90.3 was higher with strong intrinsic ATPase activity than that of AtHsp90.1. As a conclusion, the two A. thaliana cytosolic Hsp90 proteins display different functional activities depending on structural differences, implying functional divergence although the proteins are localized to the same sub-cellular organelle
Beschreibung:Date Completed 13.02.2014
Date Revised 09.04.2022
published: Print-Electronic
Citation Status MEDLINE
ISSN:1873-2690
DOI:10.1016/j.plaphy.2013.05.039