Global, segmental, and gene duplication-related processes are driving genome size and complexity in plants. Despite their evolutionary potentials, those processes can also have adverse effects on genome regulation, thus implying the existence of specialized corrective mechanisms. Here, we report that an N6-methyladenosine (m⁶A)-assisted polyadenylation (m-ASP) pathway ensures transcriptome integrity in Arabidopsis thaliana Efficient m-ASP pathway activity requires the m⁶A methyltransferase-associated factor FIP37 and CPSF30L, an m⁶A reader corresponding to an YT512-B Homology Domain-containing protein (YTHDC)-type domain containing isoform of the 30-kD subunit of cleavage and polyadenylation specificity factor. Targets of the m-ASP pathway are enriched in recently rearranged gene pairs, displayed an atypical chromatin signature, and showed transcriptional readthrough and mRNA chimera formation in FIP37- and CPSF30L-deficient plants. Furthermore, we showed that the m-ASP pathway can also restrict the formation of chimeric gene/transposable-element transcript, suggesting a possible implication of this pathway in the control of transposable elements at specific locus. Taken together, our results point to selective recognition of 3'-UTR m⁶A as a safeguard mechanism ensuring transcriptome integrity at rearranged genomic loci in plants.

中文翻译：

---

m6A 通路通过限制植物中 RNA 嵌合体的形成来保护转录组的完整性。

全局、片段和基因复制相关过程正在推动植物基因组的大小和复杂性。尽管它们具有进化潜力，但这些过程也会对基因组调控产生不利影响，因此暗示存在专门的纠正机制。在这里，我们报告了 N6-甲基腺苷 (m ⁶ A) 辅助多聚腺苷酸化 (m-ASP) 途径确保拟南芥中转录组的完整性有效的 m-ASP 途径活性需要 m ⁶ A 甲基转移酶相关因子 FIP37 和 CPSF30L，一个 m ⁶对应于包含 YT512-B 同源结构域蛋白 (YTHDC) 型结构域的阅读器，该结构域包含 30-kD 切割和聚腺苷酸化特异性因子亚基的同种型。m-ASP 通路的目标在最近重排的基因对中富集，显示出非典型的染色质特征，并在 FIP37 和 CPSF30L 缺陷植物中显示出转录通读和 mRNA 嵌合体形成。此外，我们发现 m-ASP 通路还可以限制嵌合基因/转座因子转录本的形成，表明该通路可能对特定位点的转座因子的控制产生影响。总之，我们的结果表明选择性识别 3'-UTR m ⁶ A 作为一种保护机制，可确保植物中重排基因组位点的转录组完整性。