玉米热激转录因子ZmHsf06的耐热功能及其调控通路研究OA北大核心CSTPCD

Heat frequently affects yield and quality in different growth stages of maize(Zea mays).Heat shock transcription factor(Hsf)plays important roles in improving plant heat tolerance through regulating the expression of thermotolerance-related and activating multiple downstream pathways.Based on previous studies on characteristics and thermotolerance function of maize A1 subclass ZmHsf06,this study investigated its function and molecular mechanism in regulating thermotolerance through transformation in maize and chromatin immunoprecipitation-seq(ChIP-seq),and verified the protein interaction and transcriptional activation activity further.The results showed that ZmHsf06 had transcriptional activation activity and could interact with itself.Compared with the wild type,the thermotolerance of maize lines overexpressing ZmHsf06 were significantly improved.Analyzing the downstream target genes and high enrichment pathways of ZmHsf06 by ChIP-seq,a total of 2 218 differentially enriched genes were found under heat stress,including 1 169 genes up-regulated by ZmHsf06 specially,which were mainly enriched in electron carrier activity,photosynthesis,endoplasmic reticulum protein processing and heat shock response.The ZmHsf06 binding motif had heat shock elements(HSE),the binding elements of other transcription factors such as C2C2,TEAD and MADS and some unknown elements.Electrophoretic mobility shift assay(EMSA)showed that ZmHsf06 could bind to the heat shock elements located in the promoters of 3 target genes(Zm00001d000260,Zm00001d000272 and Zm00001d033987).These results will provide evidences for furthering the study of thermotolerance function and regulation mechanism of maize Hsf family.