{"id":460,"title":"Epigenetic Remodeling Increases Plasticity of Bovine Fibroblasts Without Improving Embryo and Stem Cell Development","title_zh":"多靶点表观遗传重塑提高牛成纤维细胞可塑性但未改善胚胎与干细胞发育","url":"https://doi.org/10.64898/2026.10.28.762563","doi":"10.64898/2026.10.28.762563","pmid":null,"journal":"bioRxiv","kind":"preprint","lang":"en","published_at":"2026-10-30T00:00:00+00:00","fetched_at":"2026-11-08T03:44:14+00:00","authors":["Ambrizi DR","Moreno D","Sangalli JR","Nociti RP","Cruz JB","Pessôa LVF","Kendall D","Bressan FF","Chiaratti MR","Smith LC","Ross PJ","Meirelles FV","Sampaio RV"],"primary_topic":"early-embryo","topics":[{"slug":"early-embryo","score":3.0,"hits":["blastocyst","blastocysts","pluripotency"]},{"slug":"animal-models","score":2.4,"hits":["nuclear transfer","scnt","somatic cell nuclear transfer"]}],"topic_score":3.0,"preference_score":8.0,"preference_labels":["早期胚胎表观基因组 / 染色质"],"llm_score":62.0,"final_score":70.0,"score_dims":{"novelty":62,"rigor":58,"impact":55,"relevance":65,"translation":45},"recommend_reason":"值得浏览：多靶点表观遗传修饰鸡尾酒在牛成纤维细胞中降低抑制性组蛋白标记，但SCNT胚胎和bESC建系未获益，提供了化学重编程的阴性证据；与临床ART直接相关性有限。","keywords":["牛成纤维细胞","表观遗传重编程","体细胞核移植","胚胎干细胞","组蛋白修饰","小分子鸡尾酒"],"selected":1,"story_id":262,"llm_provider":"deepseek","llm_model":"deepseek-flash","llm_effort":"low","source_key":"europepmc-preprints","source_name":"Europe PMC · 预印本（领域内）","source_tier":1,"mention_count":1,"has_interpretation":false,"journal_key":"biorxiv","journal_tier":"standard","journal_if":null,"is_mock":false,"summary_zh":"研究用多靶点小分子鸡尾酒GUSTC（抑制EZH2、G9a/GLP、HDAC和SUV39H1）处理牛成纤维细胞，以同时干预兼性与组成性异染色质。免疫荧光显示H3K9me2/3、H3K27me3和HP1α下降、H3K9乙酰化升高；无血清培养中细胞呈克隆样并上调POU5F1/NANOG。但以其为供体进行SCNT，卵裂率、囊胚率及bESC建系效率均无显著改善。结论：GUSTC可增加牛成纤维细胞可塑性，却未提升胚胎与干细胞发育能力。","summary":"Epigenetic memory, reinforced by redundant heterochromatic networks, is a major barrier to somatic cell reprogramming. In cattle, single-agent chromatin-modifying treatments show inconsistent efficacy, likely due to compensatory crosstalk among repressive marks. Here, we evaluated a multi-target small-molecule cocktail, GUSTC, combining G SK343 (EZH2 inhibitor), U NC0638 (G9a/GLP inhibitor), S odium Butyrate (HDAC inhibitor), T richostatin A (HDAC inhibitor), and C haetocin (SUV39H1 inhibitor) to simultaneously target facultative and constitutive heterochromatin in bovine fibroblasts. At optimized, non-cytotoxic concentrations, GUSTC treatment reduced H3K9me2, H3K9me3, H3K27me3, and HP1-alpha levels while increasing H3K9 acetylation by immunofluorescence. Using GUSTC-treated fibroblasts as donor cells for somatic cell nuclear transfer did not significantly change cleavage (83.6% vs. 92.2%; p = 0.15), blastocyst rate (28.4% vs. 39.0%; p = 0.20), bovine embryonic stem cell line derivation efficiency (26.3% vs. 33.3% of seeded blastocysts; p = 0.57), or the core pluripotency marker profile (OCT4, NANOG, SOX2) of the resulting lines. In a separate, serum-free, pluripotency-permissive culture system, GUSTC-treated cells adopted a colony-like morphology and showed increased POU5F1 and NANOG expression, along with increased DNMT1, EHMT2, HDAC1, HDAC2, and SUV39H1 transcripts. GUSTC thus reduces repressive heterochromatin marks in donor fibroblasts and is associated with a potentially more reprogramming-permissive state, without detectable improvement in preimplantation developmental competence. It provides a starting point for chemical reprogramming strategies in cattle. Summary sentence A small-molecule cocktail lowers H3K9me2/3, H3K27me3, and HP1-alpha in bovine fibroblasts and increases POU5F1 and NANOG expression in serum-free culture, without improving cloned blastocyst development or embryonic stem cell establishment. Graphical abstract Proposed model: GUSTC treatment lowers repressive histone marks in bovine fibroblasts and, in serum-free culture, is associated with colony-like morphology and POU5F1 and NANOG expression. In the model, GUSTC inhibits EHMT2, SUV39H1/2, EZH2, and HDACs, relieving repression and allowing H3K9 acetylation (AC); Me2/Me3, di-/trimethylation. In contrast, SCNT with GUSTC-treated donor fibroblasts did not significantly change cleavage, blastocyst development, or bESC derivation compared with control. Alt text: Schematic titled \"Proposed model\". Left: timeline in which bovine fibroblasts in Alpha-MEM with 10% FBS are moved to KnockOut-DMEM/F12 with 20% KSR and GUSTC, form colony-like structures, and show increased plasticity. Center: in the top panel, EHMT2, SUV39H1/2, and the EZH2-containing PRC2 complex with HP1 add methyl groups to H3K9 and H3K27 while HDAC removes acetylation, so pluripotent genes are silenced; in the bottom panel, GUSTC blocks these enzymes, H3K9 is acetylated, and POU5F1 and NANOG are on. Right: timeline in which fibroblasts in Alpha-MEM with 10% FBS plus GUSTC are used for nuclear transfer embryos and bovine embryonic stem cell colonies, with no significant change compared with control.","interpretation_basis":null,"fulltext_status":null,"interpretation":null,"fulltext":{"available":false,"status":null,"reason":"尚未抓取全文（未入选、分数未达阈值，或还没跑 fulltext 步骤）","pmcid":null,"license":null,"chars":0,"source":null,"fetched_at":null}}