The UV-B photoreceptor UVR8 interacts with the LOX1 enzyme to promote stomatal closure through the LOX-derived oxylipin pathway.

ABSTRACT: Ultraviolet-B (UV-B) light-induced stomatal closure requires the photoreceptor UV RESISTANCE LOCUS 8 (UVR8) and nitric oxide (NO). However, the signaling pathways by which UV-B light regulates stomatal closure remain elusive. Here, we reveal that UVR8 signaling in the epidermis mediates stomatal closure in a tissue-specific manner in Arabidopsis (Arabidopsis thaliana). UV-B light promotes PHOSPHOLIPASE 1 (PLIP1)/PLIP3-mediated linoleic acid and α-linolenic acid accumulation and induces LIPOXYGENASE 1 (LOX1) expression. LOX1, which catabolizes linoleic acid and α-linolenic acid to produce oxylipin derivatives, acts downstream of UVR8 and upstream of the salicylic acid (SA) pathway associated with stomatal defense. Photoactivated UVR8 interacts with LOX1 and enhances its activity. Protein cr

SUBMITTER: Liu Y 

PROVIDER: S-EPMC11979336 | biostudies-literature | 2025 Apr

REPOSITORIES: biostudies-literature