Fuente: PubMed "essential OR oil extract" Plant Commun. 2026 Apr 18:101873. doi: 10.1016/j.xplc.2026.101873. Online ahead of print.ABSTRACTAbscisic acid (ABA) regulates diverse aspects of plant growth, particularly adaptive responses to abiotic stress. While the ubiquitin-proteasome system (UPS) is recognized as a pivotal pathway for degrading key ABA signaling components, the regulatory mechanisms governing 26S proteasome activity in ABA-mediated responses remain unresolved. Here, we demonstrate that Arabidopsis Proteasome Regulator 1 (PTRE1) modulates ABA signaling through regulating proteasome activity. Phenotypic analyses revealed the heightened ABA sensitivity of ptre1 mutant. Mechanistically, ABA stabilizes PTRE1 protein to enhance 26S proteasome activity. Sucrose nonfermenting1-related kinase 2.6 (SnRK2.6), the key kinase activated by ABA, directly interacts with and phosphorylates PTRE1, which is essential for PTRE1 stability and function in ABA responses. Interestingly, PTRE1 deficiency elevates ABA-Insensitive 5 protein levels, and ptre1 partially rescues the ABA insensitivity of abi5. Collectively, these findings establish a SnRK2.6-PTRE1 axis that fine-tunes proteasome activity, providing new insights into the coordinated regulation of ABA signaling through dual phosphorylation by SnRK2.6.PMID:42001233 | DOI:10.1016/j.xplc.2026.101873