论文题目: Heat shock factor C2a serves as a proactive mechanism for heat protection in developing grains in wheat via an ABA-mediated regulatory pathway

论文编号:
作者: Xiao-Jun Hu, Dandan Chen,C. Lynne Mclntyre,M. Fernanda Dreccer, Zheng-Bin Zhang（张正斌）, Janneke Drenth, Sundaravelpandian Kalaipandian, Hongping Chang,Gang-Ping Xue
刊物名称: Plant, Cell & Environment
卷期页码: Published online, ,
发表年度: 2017
DOI: http://doi.org/10.1111/pce.12957
摘要: High temperature at grain filling can severely reduce wheat yield. Heat shock factors (Hsfs) are central regulators in heat acclimation. This study investigated the role of TaHsfC2a, a member of the monocot-specific HsfC2 subclass, in the regulation of heat protection genes inTriticum aestivum. ThreeTaHsfC2ahomoeologous genes were highly expressed in wheat grains during grain filling and showed only transient up-regulation in the leaves by heat stress but were markedly up-regulated by drought and abscisic acid (ABA) treatment. Overexpression ofTaHsfC2a-Bin transgenic wheat resulted in up-regulation of a suite of heat protection genes (e.g.TaHSP70dandTaGalSyn). Most TaHsfC2a-B target genes were heat, drought and ABA inducible. Transactivation analysis of two representative targets (TaHSP70dandTaGalSyn) showed that TaHsfC2a-B activated expression of reporters driven by these target promoters. Promoter mutagenesis analyses revealed that heat shock element is responsible for transactivation by TaHsfC2a-B and heat/drought induction.TaHsfC2a-B-overexpressing wheat showed improved thermotolerance but not dehydration tolerance. Most TaHsfC2a-B target genes were co-up-regulated in developing grains withTaHsfC2agenes. These data suggest that TaHsfC2a-B is a transcriptional activator of heat protection genes and serves as a proactive mechanism for heat protection in developing wheat grains via the ABA-mediated regulatory pathway.