GEOapplication/xmlftp://ftp.ncbi.nlm.nih.gov/geo/series/GSE326nnn/GSE326317/primaryOK200TranscriptomicsArabidopsis thalianaExpression profiling by high throughput sequencinghttps://www.ncbi.nlm.nih.gov/geo/query/acc.cgi?acc=GSE326317GEOGSEfalseA GPS2-like protein interacts with HOS15 and HDA6 to form a repressor complex that regulates ABA signaling and drought adaptation in ArabidopsisPlants rely on chromatin-mediated transcriptional control to fine-tune stress responses, yet the evolutionary conservation and functional adaptation of repressor complexes remain incompletely understood. Here, we identify GPS2-like protein (GPL; AT3G47850) as the missing component of the plant equivalent of the animal NR–co-repressor complex. GPL interacts with HOS15, PWR, and HDA6/HDA9 to form a chromatin repressor module that suppresses abscisic acid (ABA)–responsive genes. Loss-of-function gpl-mutants exhibit ABA hypersensitivity and enhanced drought tolerance, while overexpression confers ABA insensitivity. Mechanistically, GPL promotes histone H3K9 deacetylation and dimethylation at stress-responsive loci and stabilizes HOS15 to ensure its nuclear retention. Global RNA-seq revealed widespread de-repression of ABA-responsive transcriptional networks in gpl-mutants. Under stress, ABA destabilizes the GPL–HOS15 complex, releasing repression and activating defense genes. These findings establish GPL as the plant homolog of GPS2 and reveal that the GPL–HOS15 repressor complex acts as a chromatin-mediated rheostat to dynamically balance growth and drought adaptation. Our work provides mechanistic insight into stress-responsive chromatin remodeling and identifies GPL as a potential target for engineering climate-resilient crops2026/05/15GSE326317GSM9629012GSM9629023GSM9629013GSM9629014GSM9629015GSM9629020GSM9629021GSM9629022GSM9629016GSM9629017GSM9629018GSM962901921179326317Arabidopsis thaliana