{"database":"GEO","file_versions":[{"headers":{"Content-Type":["application/json"]},"body":{"files":{"Other":["ftp://ftp.ncbi.nlm.nih.gov/geo/series/GSE326nnn/GSE326413/"]},"type":"primary"},"statusCode":"OK","statusCodeValue":200}],"scores":null,"additional":{"omics_type":["Transcriptomics"],"species":["Arabidopsis thaliana"],"gds_type":["Expression profiling by high throughput sequencing"],"full_dataset_link":["https://www.ncbi.nlm.nih.gov/geo/query/acc.cgi?acc=GSE326413"],"repository":["GEO"],"entry_type":["GSE"],"additional_accession":[]},"is_claimable":false,"name":"Histone chaperones ASF1s control germination by repressing PRX69","description":"Seed germination is a critical developmental decision that integrates hormonal and epigenetic signals. While physiological dormancy has been extensively studied, the molecular basis of physical dormancy—mediated by structural barriers such as the seed coat (testa)—remains poorly understood. Here, we investigate the role of Arabidopsis ASF1 histone chaperones in germination, revealing their function in altering chromatin structure to regulate testa penetrability. The asf1a1b double mutant exhibits significantly reduced germination rates, independent of ABA or GA levels. Using RNA-seq, we identified PRX69, a peroxidase implicated in testa hardening regulation, as markedly overexpressed in asf1a1b seeds. Genetic suppression of PRX69 partially rescues the asf1a1b germination defect. Additionally, by ChIP assays, we show that ASF1 proteins directly bind PRX69. Finally, loss of ASF1s disrupts H3.3 incorporation, reduces total H3 occupancy, and increases chromatin accessibility at PRX69, which is associated with RNA polymerase II enrichment. These findings establish ASF1-mediated H3.3 dynamics as a critical epigenetic mechanism controlling physical dormancy by repressing PRX69-driven testa hardening. Our research provides new insights into the interplay between epigenetic regulation and physical dormancy in plants.","dates":{"publication":"2026/04/08"},"accession":"GSE326413","cross_references":{"GSM":["GSM9630585","GSM9630584","GSM9630583","GSM9630582","GSM9630587","GSM9630586"],"GPL":["26208"],"GSE":["326413"],"taxon":["Arabidopsis thaliana"]}}