Arabidopsis Hsa32, a novel heat-shock protein, is essential for acquired thermotolerance during long recovery after acclimation

Plants and animals share similar mechanisms in the heat-shock (HS) response, such as synthesis of the conserved HS proteins (Hsps). However, because plants are confined to a growing environment, in general they require unique features to cope with heat stress. In this report, we have revealed the biological function of a novel Hsp, heat-stress-associated 32-kD protein (Hsa32), which is highly conserved in land plants but absent in most other organisms. Like other Hsps, Hsa32 protein accumulates greatly in Arabidopsis seedlings after HS treatment. Disruption of Hsa32 by T-DNA insertion does not affect growth and development under normal conditions. However, the acquired thermotolerance in the knockout line was compromised following a long recovery period after acclimation HS treatment. Our results suggest that Hsa32 is required for maintaining the duration of acquired thermotolerance, a feature that could be important to plants.


Co-researchers:HC Liu, NY Liu, FC Hsu, SS Ko