Heat Stress Responses and Thermotolerance in Maize

• Published in: International journal of molecular sciences Vol. 22; no. 2; p. 948
• Main Authors: Li, Zhaoxia, Howell, Stephen H
• Format: Journal Article
• Language: English
• Published: Switzerland MDPI AG 19.01.2021; MDPI
• Subjects: Agricultural production; Alternative splicing; Constellations; Corn; Endoplasmic reticulum; Gene expression; Gene Expression Regulation, Plant - genetics; Genes; Heat resistance; Heat shock proteins; Heat Shock Transcription Factors - genetics; Heat stress; Heat-Shock Response - genetics; Heat-Shock Response - physiology; High temperature; Homeostasis; Hot Temperature; maize; Metabolites; Plant breeding; post-transcriptional regulation; Protein folding; Proteins; Review; Splicing; Stress response; Temperature tolerance; Thermotolerance - genetics; Transcription factors; Transcriptional Activation - genetics; transcriptional regulation; Unfolded Protein Response - genetics; Zea mays - genetics; Zea mays - physiology; United States > US; heat stress; maize; post-transcriptional regulation; transcriptional regulation
• ISSN: 1422-0067; 1661-6596; 1422-0067
• DOI: 10.3390/ijms22020948

High temperatures causing heat stress disturb cellular homeostasis and impede growth and development in plants. Extensive agricultural losses are attributed to heat stress, often in combination with other stresses. Plants have evolved a variety of responses to heat stress to minimize damage and to protect themselves from further stress. A narrow temperature window separates growth from heat stress, and the range of temperatures conferring optimal growth often overlap with those producing heat stress. Heat stress induces a cytoplasmic heat stress response (HSR) in which heat shock transcription factors (HSFs) activate a constellation of genes encoding heat shock proteins (HSPs). Heat stress also induces the endoplasmic reticulum (ER)-localized unfolded protein response (UPR), which activates transcription factors that upregulate a different family of stress response genes. Heat stress also activates hormone responses and alternative RNA splicing, all of which may contribute to thermotolerance. Heat stress is often studied by subjecting plants to step increases in temperatures; however, more recent studies have demonstrated that heat shock responses occur under simulated field conditions in which temperatures are slowly ramped up to more moderate temperatures. Heat stress responses, assessed at a molecular level, could be used as traits for plant breeders to select for thermotolerance.