Dear Sarbesh,

Please, see the following publications:

1-Plant Cell. 2000 Apr; 12(4): 479–492.

PMCID: PMC139847

Heat Shock Protein 101 Plays a Crucial Role in Thermotolerance in Arabidopsis

Christine Queitsch,a Suk-Whan Hong,b Elizabeth Vierling,b and Susan Lindquist1,a

Author information ► Article notes ► Copyright and License information ►

This article has been cited by other articles in PMC.

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ABSTRACT

Plants are sessile organisms, and their ability to adapt to stress is crucial for survival in natural environments. Many observations suggest a relationship between stress tolerance and heat shock proteins (HSPs) in plants, but the roles of individual HSPs are poorly characterized. We report that transgenic Arabidopsis plants expressing less than usual amounts of HSP101, a result of either antisense inhibition or cosuppression, grew at normal rates but had a severely diminished capacity to acquire heat tolerance after mild conditioning pretreatments. The naturally high tolerance of germinating seeds, which express HSP101 as a result of developmental regulation, was also profoundly decreased. Conversely, plants constitutively expressing HSP101 tolerated sudden shifts to extreme temperatures better than did vector controls. We conclude that HSP101 plays a pivotal role in heat tolerance in Arabidopsis. Given the high evolutionary conservation of this protein and the fact that altering HSP101 expression had no detrimental effects on normal growth or development, one should be able to manipulate the stress tolerance of other plants by altering the expression of this protein.

2-Role of plant heat-shock proteins and molecular chaperones in the abiotic

stress response

Wangxia Wang1,3, Basia Vinocur1

, Oded Shoseyov1,2 and Arie Altman1,2

Abiotic stresses usually cause protein dysfunction. Maintaining proteins in their functional conformations and preventing the aggregation of non-native proteins

are particularly important for cell survival under stress. Heat-shock proteins (Hsps)/chaperones are responsible for protein folding, assembly, translocation and degradation in many normal cellular processes, stabilize proteins and membranes, and can assist in protein refolding under stress conditions. They can play a

crucial role in protecting plants against stress by reestablishing normal protein conformation and thus cellular homeostasis. Here, we summarize the significance

of Hsps and chaperones in abiotic stress responses in plants, and discuss the co-operation among their different classes and their interactions with other tressinduced components.

See attached file.

3-Small heat shock proteins and stress tolerance in plants

Weining Sun, Marc Van Montagu*, Nathalie Verbruggen1

Vakgroep Moleculaire Genetica, Departement Plantengenetica, Vlaams Instituut voor Biotechnologie (VIB), Universiteit Gent,

K.L. Ledeganckstraat 35, B-9000 Gent, Belgium

Received 8 August 2001; received in revised form 2 May 2002; accepted 4 June 2002

Abstract

Small heat shock proteins (sHsps) are produced ubiquitously in prokaryotic and eukaryotic cells upon heat. The special importance of sHsps in plants is suggested by unusual abundance and diversity. Six classes of sHsps have been identified in plants based on their intracellular localization and sequence relatedness. In addition to heat stress, plant sHsps are also produced under other stress conditions and at certain developmental stages. Induction of sHsp gene expression and protein accumulation upon environmental stresses point to the hypothesis that these proteins play an important role in stress tolerance. The function of sHsps as molecular chaperones is supported by in vitro and in vivo assays. This review summarizes recent knowledge about plant sHsp gene expression, protein structure and functions.

D 2002 Elsevier Science B.V. All rights reserved.

Keywords: Chaperone; Embryogenesis; Transgenic plant

See attached file

Hoping this will be helpful,

Rafik