Analysis Of HSP Gene Family And Characterization Of BhHSP70-1 Gene In The Resurrection Plant Boea Hygrometrica

Heat shock proteins(HSPs)which were initially found to be induced by heat shock,are chaperones playing important roles in abiotic stress tolerance to cold,drought,salt and heavy metal ions in plants.The resurrection plant Boea hygrometrica acquires desiccation tolerance after drought acclimation.However,the roles of HSPs in its desiccation tolarance remain elusive.For this issue,this study includes the following three aspects: 1)36 HSPs from B.hygrometrica(Bh HSPs)which identified from a transcriptom sequencing of this resurrection plant were subjected to bioinformatic analysis.2)Expression patterns of the 36 Bh HSPs under various stresses and treatments were detected by using Real-time PCR;and 29 of these Bh HSPs were cloned and their subcellular localization was observed.3)Transgenic Arabidopsis expressing Bh HSP70-1 was generated to analyse function of this gene.Four conclusions were drawn from this research: 1)36 Bh HSPs including 3 Bh HSP90 s,7 Bh HSP70 s,16 Bh DNAJs and 10 Bhs HSs P,contain typical HSP character sequences which evolutionarily conserved.2)Expression of Bh HSPs were induced by various stressse,and Bh HSPs genes belonging to same or different families have different expression patterns in response to stress treatments.Bh HSPs coding low molecular weight HSPs were significantly induced by stresses,indicating they played important roles in acquiration of desiccasion tolerance and resistance to other stresses in B.hygrometrica.3)29 Bh HSPs genes,including 3 Bh HSP70 s,16 Bh DNAJs and 10 Bhs HSPs were cloned from B.hygrometrica.4)Bh HSP70-1 localized in the cytoplasm and nucleus,and its expression was induced by dehydration and cold treatment.Transgenic plants overexpressing Bh HSP70-1 had tolerance to hypertonic,Na Cl and endoplasmic reticulum stresses.Putting together,these results indicated that Bh HSPs,a multi-member and functional superfamily in B.hygrometrica,played vital roles for the survival of B.hygrometrica under stress conditions,shedding light on agricultural engineering for stress tolerant crops.