Bi H, Zhao Y, Li H, Liu W.

Int J Mol Sci. 2020 Apr 28;21(9). pii: E3121. doi: 10.3390/ijms21093121.

Abstract

Abiotic stresses are major constraints limiting crop growth and production. Heat shock factors (Hsfs) play significant roles in mediating plant resistance to various environmental stresses, including heat, drought and salinity. In this study, we explored the biological functions and underlying mechanisms of wheat TaHsfA6f in plant tolerance to various abiotic stresses. Gene expression profiles showed that TaHsfA6f has relatively high expression levels in wheat leaves at the reproductive stage. Transcript levels of TaHsfA6f were substantially up-regulated by heat, dehydration, salinity, low temperature, and multiple phytohormones, but was not induced by brassinosteroids (BR). Subcellular localization analyses revealed that TaHsfA6f is localized to the nucleus. Overexpression of the TaHsfA6f gene in Arabidopsis results in improved tolerance to heat, drought and salt stresses, enhanced sensitivity to exogenous abscisic acid (ABA), and increased accumulation of ABA. Furthermore, RNA-sequencing data demonstrated that TaHsfA6f functions through up-regulation of a number of genes involved in ABA metabolism and signaling, and other stress-associated genes. Collectively, these results provide evidence that TaHsfA6f participates in the regulation of multiple abiotic stresses, and that TaHsfA6f could serve as a valuable gene for genetic modification of crop abiotic stress tolerance.

See https://www.mdpi.com/1422-0067/21/9/3121

Figure 7: Transcriptomic analyses of TaHsfA6f transgenic Arabidopsis. (A) Heat map of DEGs in leaves of transgenic vs. WT plants. The heat map represents the gene expression levels of 674 significant DEGs (log2Foldchange > 1 and FDR < 0.001) between transgenic (L1: rep1, rep2 and rep3) and WT (WT: rep1, rep2 and rep3) plants. The indicated scale is the log2 value of the normalized level of gene expression. (B) Gene ontology classification for DEGs in TaHsfA6f transgenic and WT plants. (C) qPCR validation of RNA-seq results for DEGs. Error bars indicate standard deviations.