A Heat Shock Transcription Factor Gene (Hahsfa1) from a Desert Shrub, Haloxylon Ammodendron, Elevates Salt Tolerance in Arabidopsis Thaliana

Haloxylon ammodendron is a typical desert xerophyte with worthy genetic resources, so the discovery of its resistance genes is necessary in order to upgrade the defiance in other plant species through the genetic engineering method. In this study, the full-length cDNA of HaHSFA1 , a gene encoding a heat stress transcription factor, was cloned from the desert plant H. ammodendron , and the overexpression vector was constructed and transformed into Arabidopsis thaliana . We analyzed the sensitivity of Arabidopsis seedlings of overexpressing HaHSFA1 to exogenous ABA, osmotic stress, and salt stress, and deeply investigated the effect of HaHSFA1 overexpression in Arabidopsis plants on salt tolerance. We found that overexpression of HaHSFA1 increased chlorophyll content in Arabidopsis plants, promoted their growth, and increased leaf soluble sugar and proline content, decreased osmotic potential, as well, which in turn maintained higher aboveground water content. Overexpression of HaHSFA1 also enhanced antioxidase activity and alleviated damage to the membrane system by secondary oxidative stress, thereby, maintaining lower relative plasma membrane permeability. Overexpression of HaHSFA1 improved root activity too and increased plant K + / Na + selective uptake capacity. The present study showed that overexpression of HaHSFA1 significantly elevated salt tolerance in Arabidopsis plants, and also revealed the potential application of the HaHSFA1 gene of H. ammodendron in improving abiotic stress tolerance in other plant species