Abstract:

As a key regulating factor in response to various abiotic stresses,plant heat shock transcription factor (Hsf) has a big family,and diverse structure,characteristics and functions.Hsf not only directly regulates Hsp and other relative gene expression and participates in the processes of response and adaption to various abiotic stresses,but also mediates many life activities regulation.Since the first Hsf was cloned from yeast in the 1980s,more and more Hsfs from other species have been identified and studied.In the previous reports,the identification of the Hsf family in plants was performed only in model species such as Arabidopsis and tomato.Furthermore,the studies is mainly focused on the HsfA subfamily,with few studies on the HsfB subfamily.And,the precise function of HsfC family is also largely unknown.With global climate change,the frequent occurrence of extremely high temperature events has seriously threatened the yield and quality of wheat,maize and other crops.To deal with the threat posed by heat stress,unraveling the mechanism of thermotolerance,identifying functional the targeted Hsfs and improving stress tolerance of crop through biotechnology methods is important.The number of Hsf family in field crops is various,the genome is complex,and the related research started lately compared with model species.To this end,our laboratory began to study the Hsf family of crops in 2009.Based on the latest genomic information,we confirmed the number of members,the modular structure and the spatio-temporal expression pattern of Hsf family.At the same time,with the help of transgenic wheat and mutant by genetic transformation and the CRISPR/Cas9 clustered regularly interspaced palindromic repeats (CRISPR)/CRISPR-associated protein mediated genome editing technology,several Hsfs were cloned and their regulatory functions of thermotolerance were identified,and some mechanism of thermotolerance was clarified.Our research not only enriched the theoretical basis of thermotolerance,but also provided new germplasm for biological breeding.At present,many studies have reported on functional identification and transcriptional regulation of Hsfs,however,evidences lack on which upstream component mediate Hsf's participation in regulation of thermotolerance,and the related mechanism is still unknown.Based on previous research results about wheat and maize Hsf families of lab,and many relative reports published in public,we reviewed the roles and mechanisms of plant Hsf in regulating process reported in recent years,aiming to promote research in illustrating the extensive and special roles and regulation network of plant Hsf family further,and dig useful genes and selective QTLs for biological breeding for plant thermotolerance.

Key words: Plant heat shock transcription factor, Abiotic stresses, Function and mechanism, Regulation network