ABSTRACT Plants use intricate mechanisms to adapt to changing iron conditions because iron is essential and also one of the most limiting nutrients for plant growth. Furthermore, iron is potentially toxic in excess and must be tightly regulated. Previously, we showed that chromatin remodeling via histone 3 lysine 27 trimethylation (H3K27me3) modulates the expression of FIT-dependent genes under iron deficiency in roots. This study builds on our previous findings, showing that H3K27me3 also modulates iron regulation in shoots. In the clf mutant, which lacks the predominant H3K27 tri-methyltransferase, we detected increased iron translocation to shoots under iron deficiency as compared to wild type. Transcriptomic analysis of shoots also revealed differential expression of genes consistent with higher iron levels in clf shoots than wild type shoots under iron-deficient conditions. In addition, we verify that YSL1 and IMA1, two genes involved in signaling iron status from shoots to roots, are direct targets of H3K27me3 and reveal iron-dependent deposition of H3K27me3 on these loci. This study contributes to a better understanding of the molecular mechanisms behind iron regulation in plants, as the effect of PRC2-mediated H3K27me3 on iron homeostasis genes expressed in the shoots has not been previously reported to our knowledge.

中文翻译：

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PRC2 介导的 H3K27me3 调节拟南芥枝条铁稳态

摘要 植物使用复杂的机制来适应不断变化的铁条件，因为铁是必不可少的，也是植物生长最受限制的营养物质之一。此外，过量的铁可能有毒，必须严格监管。以前，我们表明通过组蛋白 3 赖氨酸 27 三甲基化 (H3K27me3) 进行的染色质重塑可调节根缺铁条件下 FIT 依赖性基因的表达。这项研究建立在我们之前的研究结果的基础上，表明 H3K27me3 还调节枝条中的铁调节。在缺乏主要 H3K27 三甲基转移酶的 clf 突变体中，与野生型相比，我们检测到缺铁条件下向芽中的铁易位增加。芽的转录组学分析还揭示了在缺铁条件下与野生型芽相比，在 clf 芽中铁水平更高的基因的差异表达。此外，我们验证了 YSL1 和 IMA1 这两个参与从芽到根发出铁状态信号的基因是 H3K27me3 的直接靶标，并揭示了 H3K27me3 在这些基因座上的铁依赖性沉积。这项研究有助于更好地了解植物铁调节背后的分子机制，因为我们之前没有报道过 PRC2 介导的 H3K27me3 对枝条中表达的铁稳态基因的影响。是 H3K27me3 的直接靶标并揭示 H3K27me3 在这些基因座上的铁依赖性沉积。这项研究有助于更好地了解植物中铁调节背后的分子机制，因为我们之前没有报道过 PRC2 介导的 H3K27me3 对枝条中表达的铁稳态基因的影响。是 H3K27me3 的直接靶标并揭示 H3K27me3 在这些基因座上的铁依赖性沉积。这项研究有助于更好地了解植物中铁调节背后的分子机制，因为我们之前没有报道过 PRC2 介导的 H3K27me3 对枝条中表达的铁稳态基因的影响。