{"id":427,"title":"Multiple Argonaute complexes orchestrate epigenetic silencing in the Arabidopsis germline","title_zh":"多种Argonaute复合体协同调控拟南芥雄性生殖系的表观遗传沉默","url":"https://pubmed.ncbi.nlm.nih.gov/42869904","doi":"10.1038/s41467-026-77326-1","pmid":"42869904","journal":"Nat Commun","kind":"paper","lang":"en","published_at":"2026-09-12T00:00:00+00:00","fetched_at":"2026-11-08T03:44:13+00:00","authors":["Long J","Yang C","Xu S","De Jaeger-Braet J","She W","Ono S","Walker J","De Souza-Vieira Y","Schnittger A","Feng X"],"primary_topic":"ivg-stem","topics":[{"slug":"ivg-stem","score":4.0,"hits":["germline"]},{"slug":"oocyte","score":1.0,"hits":["meiotic"]},{"slug":"repro-genetics","score":1.0,"hits":["dna methylation"]},{"slug":"omics-methods","score":1.0,"hits":["transcriptomic"]}],"topic_score":4.0,"preference_score":0.0,"preference_labels":[],"llm_score":56.0,"final_score":64.0,"score_dims":{"novelty":80,"rigor":82,"impact":38,"relevance":28,"translation":20},"recommend_reason":"机制层面清晰有力：多AGO复合体分工协作、剂量依赖的生殖系表观沉默，对理解小RNA–Argonaute在配子发生中的作用有参考价值；但研究对象为拟南芥，属植物生殖生物学，与人类辅助生殖、胚胎多组学的直接相关性有限，适合关注生殖系表观遗传机制的读者浏览。","keywords":["Argonaute","小RNA","DNA甲基化","生殖系表观遗传","减数分裂","拟南芥"],"selected":1,"story_id":441,"llm_provider":"deepseek","llm_model":"deepseek-flash","llm_effort":"low","source_key":"pubmed-top-journals","source_name":"PubMed · CNS/大子刊/四大医学刊（生殖相关）","source_tier":1,"mention_count":1,"has_interpretation":false,"journal_key":"nat-commun","journal_tier":"cns-sub","journal_if":14.7,"is_mock":false,"summary_zh":"研究以拟南芥雄性生殖系为对象，鉴定生殖细胞小RNA（sRNA）的效应蛋白。结果显示，雄性生殖系sRNA与AGO4、AGO5、AGO6、AGO9结合，并与RNA聚合酶V（Pol V）共富集于减数分裂细胞（meiocyte），使sRNA能够甲基化序列同源性不高的位点。AGO4/6/9主要装载Pol IV来源的24 nt sRNA，以剂量依赖方式介导DNA甲基化；AGO5虽与AGO1/AGO10同源性更近，却主要结合CLSY3与Pol IV来源的21–24 nt sRNA。单基因与复合ago突变体的转录组与甲基化组分析表明，AGO4/6/9与AGO5在调控蛋白编码基因与沉默转座子方面分工不同又相互补充，并伴随显著减数分裂缺陷。结论：DNA甲基化（AGO4/6/9）与可能的转录后沉默（AGO5）协同促进雄性生殖系发育。","summary":"Small RNAs (sRNAs) are widespread across diverse flowering plant species and play important roles regulating reproduction and environmental responses. However, how sRNAs exert their function is largely unknown, likely due to their typical origin in non-genic regions, the lack of distinct gene targets, and the sparse characterization of their associated Argonaute (AGO) effector proteins. Here we show that Arabidopsis male reproductive sRNAs associate with AGO4, 5, 6 and 9, all of which are enriched in meiocytes along with RNA Polymerase V (Pol V). This enables these sRNAs to methylate loci with imperfect sequence homology. AGO4, AGO6 and AGO9 predominantly load 24-nucleotide (nt) Pol IV-derived sRNAs and mediate DNA methylation in meiocytes in a dosage-dependent manner. Despite closer homology to microRNA-associated AGO1 and AGO10, AGO5 primarily binds CLSY3- and Pol IV-derived 21-24 nt sRNAs. Transcriptomic and methylomic analyses of meiocytes from single and compound ago mutants demonstrate distinct yet complementary roles of AGO4/6/9 and AGO5 in regulating protein-coding genes and silencing transposons in the germline. These molecular disruptions are accompanied by significant meiotic defects. Together, our findings reveal how AGO4/6/9-mediated DNA methylation and AGO5, likely acting through post-transcriptional gene silencing, work together to promote male germline development.","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}}