The heat response regulators HSFA1s promote Arabidopsis thermomorphogenesis via stabilizing PIF4 during the day

Abstract

During summer, plants often experience increased light inputs and high temperatures, two major environmental factors with contrasting effects on thermomorphological traits. The integration of light and temperature signaling to control thermomorphogenesis in plants is critical for their acclimation in such conditions, but the underlying mechanisms remain largely unclear. We found that heat shock transcription factor 1d (HSFA1d) and its homologs are necessary for plant thermomorphogenesis during the day. In response to warm daytime temperature, HSFA1s markedly accumulate and move into the nucleus where they interact with phytochrome-interacting factor 4 (PIF4) and stabilize PIF4 by interfering with phytochrome B–PIF4 interaction. Moreover, we found that the HSFA1d nuclear localization under warm daytime temperature is mediated by constitutive photomorphogenic 1–repressed GSK3-like kinase BIN2. These results support a regulatory mechanism for thermomorphogenesis in the daytime mediated by the HSFA1s-PIF4 module and uncover HSFA1s as critical regulators integrating light and temperature signaling for a better acclimation of plants to the summer high temperature.

Effects of high-temperature stress on gene expression related to photosynthesis in two jujube ( Ziziphus jujuba Mill.) varieties

“… 42 , 43 Under salt and alkali stress, six proteins related to photosynthesis, such as PsaK, were significantly upregulated in malonia, and these proteins could act as regulators of the PSI repair system. 44 A total of 10 DEGs and transcription factors in photosynthesis in response to high-temperature stress were identified in this study, including three PIF4 transcription factors, two HSFA transcription factors, four ROS genes, and one HY5 gene, and their expression was upregulated in F after high-temperature stress, However, downregulated expression of these genes was also observed in J ( Figure 6 ). It was suggested that high temperature stress induced the expression of these genes, which helped to stabilize the structure of PSII and PSI from being damaged by high temperature.…”

The ELF3-BBX24/BBX25-PIF4 module controls thermosensory growth in Arabidopsis

“…Several thermosensory signaling components such as HMR (HEMERA), RCB (REGULATOR OF CHLOROPLAST BIOGENESIS), and HSFA1s (HEAT SHOCK TRANSCRIPTION FACTOR 1) have been shown to stabilize PIF4 and promote daytime mediated thermomorphogenic growth (Qiu et al, 2021; Tan et al, 2023b). Meanwhile, COP1/DET1/SPA, upstream regulators of PIF4, stabilize PIF4 during the night (Gangappa and Kumar, 2017).…”

“…Recent studies also reveal that the HEMERA-REGULATOR OF the CHLOROPLAST BIOGENESIS (HMR/RCB) module works cooperatively to stabilize PIF4 during the day and promote thermomorphogenesis (Qiu et al, 2019; Qiu et al, 2021). The Heat shock transcription factor (HSF), family members, and HSFA1a/b/d/e interact with PIF4 and stabilize it during light by interfering with PIF4-phyB interaction, resulting in thermomorphogenesis during the day (Tan et al, 2023a).…”

Haplotype-resolved genome of Prunus zhengheensis provides insight into its evolution and low temperature adaptation in apricot

“…HSFs are highly conserved key regulators of the heat stress response in mammals, yeast and plants [ 83 ]. Among these HSF factors, the master regulators of the heat shock response in A. thaliana are HSFA1a , HSFA1b and HSFA1d .…”

“…For example, Tan et al . reported that under warm daytime conditions, HSFA1 accumulated significantly and entered the nucleus, interacted with PIF4, and stabilized PIF4 by interfering with the photochrome B-PIF4 interaction [ 83 ]. In addition to responding to high temperatures, HSFA1 also responded to low temperatures.…”