Article

Arabidopsis thaliana J-class heat shock proteins: cellular stress sensors

Functional and Integrative Genomics (impact factor: 2.84). 04/2012; 9(4):433-446. DOI:10.1007/s10142-009-0132-0 pp.433-446

ABSTRACT Plants are sessile organisms that have evolved a variety of mechanisms to maintain their cellular homeostasis under stressful
environmental conditions. Survival of plants under abiotic stress conditions requires specialized group of heat shock protein
machinery, belonging to Hsp70:J-protein family. These heat shock proteins are most ubiquitous types of chaperone machineries
involved in diverse cellular processes including protein folding, translocation across cell membranes, and protein degradation.
They play a crucial role in maintaining the protein homeostasis by reestablishing functional native conformations under environmental
stress conditions, thus providing protection to the cell. J-proteins are co-chaperones of Hsp70 machine, which play a critical
role by stimulating Hsp70s ATPase activity, thereby stabilizing its interaction with client proteins. Using genome-wide analysis
of Arabidopsis thaliana, here we have outlined identification and systematic classification of J-protein co-chaperones which are key regulators of
Hsp70s function. In comparison with Saccharomyces cerevisiae model system, a comprehensive domain structural organization, cellular localization, and functional diversity of A. thaliana J-proteins have also been summarized.

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Keywords

A. thaliana J-proteins
 
abiotic stress conditions
 
cellular homeostasis
 
cellular localization
 
chaperone machineries
 
client proteins
 
comprehensive domain structural organization
 
crucial role
 
diverse cellular processes
 
heat shock proteins
 
Hsp70s function
 
J-protein co-chaperones
 
J-proteins
 
protein degradation
 
protein folding
 
protein homeostasis
 
reestablishing functional native conformations
 
Saccharomyces cerevisiae model system
 
stimulating Hsp70s ATPase activity
 
systematic classification