Transcriptional Regulatory Network of Plant Heat Stress Response

HEAT SHOCK TRANSCRIPTION FACTOR A1s (HsfA1s) are the master transcriptional regulators of the HSR. A transcriptional network comprising many TFs and other transcriptional regulators controls the expression of HS-inducible genes throughout the HSR. The activity of HsfA1s and DEHYDRATION-RESPONSIVE ELEMENT BINDING PROTEIN 2A (DREB2A) is tightly controlled through post-translational regulation. Small RNAs, histone modifiers, and transposons are involved in transcriptional regulation and stress memory in the HSR. Ca2+ and reactive oxygen species are involved in a signaling pathway that connects HS sensors and transcriptional regulators. Heat stress (HS) is becoming an increasingly significant problem for food security as global warming progresses. Recent studies have elucidated the complex transcriptional regulatory networks involved in HS. Here, we provide an overview of current knowledge regarding the transcriptional regulatory network and post-translational regulation of the transcription factors involved in the HS response. Increasing evidence suggests that epigenetic regulation and small RNAs are important in heat-induced transcriptional responses and stress memory. It remains to be elucidated how plants sense and respond to HS. Several recent reports have discussed the heat sensing and signaling that activate transcriptional cascades; thus, we also highlight future directions of promoting crop tolerance to HS using these factors or other strategies for agricultural applications. Heat stress (HS) is becoming an increasingly significant problem for food security as global warming progresses. Recent studies have elucidated the complex transcriptional regulatory networks involved in HS. Here, we provide an overview of current knowledge regarding the transcriptional regulatory network and post-translational regulation of the transcription factors involved in the HS response. Increasing evidence suggests that epigenetic regulation and small RNAs are important in heat-induced transcriptional responses and stress memory. It remains to be elucidated how plants sense and respond to HS. Several recent reports have discussed the heat sensing and signaling that activate transcriptional cascades; thus, we also highlight future directions of promoting crop tolerance to HS using these factors or other strategies for agricultural applications. a plant-specific transcription factor involved in both drought and HS responses. transcription factor necessary for the induction of the HSR. Although HSFs are evolutionally conserved among eukaryotes, plants have diversified HSF families compared with animals. stress caused by temperatures far exceeding optimal growth conditions that damages cellular components through mechanisms such as membrane fluidization, ROS generation, and protein denaturation. These phenomena not only damage cells, but also act as HS signals. physiological response to cope with HS. This review mainly addresses the regulatory mechanisms of the HSR at the transcriptional level, focusing on the functions and regulation of the activity of transcriptional regulators in particular. The ‘early’ HSR refers to the HS-responsive events that occur for up to approximately 2 h after 37°C HS in Arabidopsis thaliana, when HsfA1 and its target transcription factors start to function. the ability to survive and continue to grow in HS conditions.