PMID- 10759842
OWN - NLM
STAT- MEDLINE
DCOM- 20000613
LR  - 20231213
IS  - 0014-2956 (Print)
IS  - 0014-2956 (Linking)
VI  - 267
IP  - 8
DP  - 2000 Apr
TI  - High-molecular-mass complexes formed in vivo contain smHSPs and HSP70 and display 
      chaperone-like activity.
PG  - 2195-207
AB  - Stress can have profound effects on the cell. The elicitation of the stress 
      response in the cell is often accompanied by the synthesis of high-molecular-mass 
      complexes, sometimes termed heat shock granules (HSGs). The presence of the 
      complexes has been shown to be important for the survival of cells subjected to 
      stress. We purified these complexes from heat-stressed BY-2 tobacco cells. HSG 
      complexes formed in vivo contain predominantly smHSPs, HSP40 and HSP70 and 
      display chaperone-like activity. Tubulins as well as other proteins may be part 
      of the complex or its substrate. The proteins, except smHSPs and to some extent 
      HSP70, were hypersensitive to proteolysis, suggesting that they were partially 
      denatured and not an integral part of the HSG complexes. When citrate synthase 
      was used as the substrate, in vivo generated HSG complexes exhibited strong 
      nucleotide-dependent in vitro chaperone activity. Measurable ATP-mediated 
      hydrolytic activity was detected. Isolated HSG complexes are stable until ATP is 
      added, which leads to rapid dissociation of the complex into subunits. It is 
      proposed that smHSPs form the core of the complex in association with 
      ATP-dependent HSP70 and HSP40 cochaperones. Implications of these findings are 
      discussed.
FAU - Smykal, P
AU  - Smykal P
AD  - Department of Plant Physiology, Charles University, Prague, Czech Republic.
FAU - Hrdy, I
AU  - Hrdy I
FAU - Pechan, P M
AU  - Pechan PM
LA  - eng
PT  - Journal Article
PT  - Research Support, Non-U.S. Gov't
PL  - England
TA  - Eur J Biochem
JT  - European journal of biochemistry
JID - 0107600
RN  - 0 (HSP40 Heat-Shock Proteins)
RN  - 0 (HSP70 Heat-Shock Proteins)
RN  - 0 (Heat-Shock Proteins)
RN  - 0 (Macromolecular Substances)
RN  - 0 (Molecular Chaperones)
RN  - 0 (Plant Proteins)
RN  - 8L70Q75FXE (Adenosine Triphosphate)
RN  - EC 2.3.3.1 (Citrate (si)-Synthase)
RN  - EC 3.4.21.64 (Endopeptidase K)
SB  - IM
MH  - Adenosine Triphosphate/metabolism/pharmacology
MH  - Cell Line
MH  - Chromatography, High Pressure Liquid
MH  - Citrate (si)-Synthase/metabolism
MH  - Electrophoresis, Polyacrylamide Gel
MH  - Endopeptidase K/metabolism
MH  - Enzyme Activation
MH  - HSP40 Heat-Shock Proteins
MH  - HSP70 Heat-Shock Proteins/*analysis
MH  - Heat-Shock Proteins/*analysis/chemistry
MH  - Immunoblotting
MH  - Kinetics
MH  - Macromolecular Substances
MH  - Microscopy, Electron
MH  - Molecular Chaperones/*chemistry
MH  - Plant Proteins/*chemistry
MH  - Plants, Toxic
MH  - Scattering, Radiation
MH  - Temperature
MH  - Nicotiana
EDAT- 2000/04/12 09:00
MHDA- 2000/06/17 09:00
CRDT- 2000/04/12 09:00
PHST- 2000/04/12 09:00 [pubmed]
PHST- 2000/06/17 09:00 [medline]
PHST- 2000/04/12 09:00 [entrez]
AID - ejb1223 [pii]
AID - 10.1046/j.1432-1327.2000.01223.x [doi]
PST - ppublish
SO  - Eur J Biochem. 2000 Apr;267(8):2195-207. doi: 10.1046/j.1432-1327.2000.01223.x.