Thermosensory pathway makes a U-turn to respond to heat
- 1Fundacion Instituto Leloir
Abstract
Plant organs exhibit a unimodal growth response to temperature, yet the mechanistic links connecting growth-promoting and growth-inhibiting thermal ranges remain unresolved. In Arabidopsis seedlings, warm temperatures promote hypocotyl elongation by relieving phytochrome B (phyB) inhibition, thereby activating the transcription factors PIF4 and PIF7 to drive auxin synthesis. Here, we demonstrate that temperatures beyond the growth optimum actively suppress growth by downregulating auxin levels, auxin signalling, and PIF4 abundance specifically within the cotyledons, the primary site of auxin production. Strikingly, whereas warm temperatures induce the shrinking of phyB nuclear bodies, heat stress causes phyB to assemble into enlarged condensates, a behaviour faithfully recapitulated in mammalian cells, demonstrating an intrinsic biophysical mechanism. Together, our findings indicate that heat-induced growth inhibition is not merely passive stress damage, but an active molecular reversal of the promotive pathway of thermomorphogenesis.
Related
- Dietary esculetin improves growth performance and spleen function via the NF-κB/MAPK pathway in heat-stressed broilers.
- Heat shock pathway activation by TRC051384 protects spiral ganglion neurons from noise-induced hearing loss
- Integrative transcriptomic and functional analyses identify TaARF in the auxin response pathway as a hub gene conferring multi-stage heat tolerance in wheat
- Sense-and-respond: Engineered bacteria drive epithelial repair during gut inflammation
- Territorial African wood-doves respond differently to intruders with higher and lower frequency of songs
BibTeX
@misc{bianchimano2026thermosensory,
title = {{Thermosensory pathway makes a U-turn to respond to heat}},
author = {L. Bianchimano and C. S. Koh and M. B. De Luca and M. G. Murcia and M. E. Pereyra and A. B. Hamacher and M. Zurbriggen and J. Casal},
howpublished = {bioRxiv},
year = {2026},
month = nov,
doi = {10.64898/2026.11.06.764838},
url = {https://www.biorxiv.org/content/10.64898/2026.11.06.764838v1},
note = {CC BY-NC-ND},
}
RIS
TY - UNPB
TI - Thermosensory pathway makes a U-turn to respond to heat
AU - L. Bianchimano
AU - C. S. Koh
AU - M. B. De Luca
AU - M. G. Murcia
AU - M. E. Pereyra
AU - A. B. Hamacher
AU - M. Zurbriggen
AU - J. Casal
PY - 2026
DA - 2026/11/06
PB - bioRxiv
DO - 10.64898/2026.11.06.764838
UR - https://www.biorxiv.org/content/10.64898/2026.11.06.764838v1
AB - Plant organs exhibit a unimodal growth response to temperature, yet the mechanistic links connecting growth-promoting and growth-inhibiting thermal ranges remain unresolved. In Arabidopsis seedlings, warm temperatures promote hypocotyl elongation by relieving phytochrome B (phyB) inhibition, thereby activating the transcription factors PIF4 and PIF7 to drive auxin synthesis. Here, we demonstrate that temperatures beyond the growth optimum actively suppress growth by downregulating auxin levels, auxin signalling, and PIF4 abundance specifically within the cotyledons, the primary site of auxin production. Strikingly, whereas warm temperatures induce the shrinking of phyB nuclear bodies, heat stress causes phyB to assemble into enlarged condensates, a behaviour faithfully recapitulated in mammalian cells, demonstrating an intrinsic biophysical mechanism. Together, our findings indicate that heat-induced growth inhibition is not merely passive stress damage, but an active molecular reversal of the promotive pathway of thermomorphogenesis.
ER -