Taking the Heat

Abstract

Heat shock proteins (HSPs) are well-known mediators of the stress response in many organisms. Although heat shock proteins have been implicated in plant response to thermal stress, the role of specific heat shock proteins in mediating the response to thermotolerance is poorly defined. Basal thermotolerance is the ability to withstand a nonlethal heat stress; acquired thermotolerance is the ability to withstand a normally lethal heat stress by preconditioning with a milder heat stress. Queitsch et al. demonstrate that HSP101 is essential to mediating the response to both acquired and basal thermotolerance. Arabidopsis plants with decreased levels of HSP101 due to antisense inhibition or cosuppression did not exhibit acquired thermotolerance in whole-plant recovery assays or hypocotyl elongation assays. Furthermore, constitutive expression of HSP101 resulted in a growth advantage for plants subjected to heat shock such that plants overexpressing HSP101 recovered from 45-minute heat shock, but control plants did not. Germinating Arabidopsis seeds have a high basal thermotolerance that is lost if HSP101 expression is inhibited. Thus, HSP101 plays an important role in plant thermotolerance. W. Gurley highlights this work in a commentary. Queitsch, C., Hong, S.-W., Vierling, E., and Lindquist, S. (2000) Heat shock protein 101 plays a crucial role in thermotolerance in Arabidopsis. Plant Cell 12 : 479-492. [Abstract] [Full Text] Gurley, W.B. (2000) HSP101: A key component for the acquisition of thermotolerance in plants. Plant Cell 12 : 457-460. [Full Text]