Transcriptional Regulatory Network of Plant Heat Stress Response

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 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.