Jiangsu Key Laboratory of Phylogenomics and Comparative Genomics, School of Life Sciences, Jiangsu Normal University, Xuzhou, 221116, China.
Department of Applied Biology, College of Agriculture and Life Sciences, Chonnam National University, Gwangju, 61186, Korea.
Plant Physiol. 2022 Mar 28;188(4):2215-2227. doi: 10.1093/plphys/kiab509.
N6-methyladenosine (m6A) is the most abundant internal modification in eukaryotic messenger RNA. Although the role of m6A has been demonstrated in many biological processes, including embryonic development, flowering time control, microspore generation, fruit ripening, and stress responses, its contribution to other aspects of plant development still needs to be explored. Herein, we show the potential link between m6A deposition and the expansion of tomato (Solanum lycopersicum) fruits through parallel m6A-immunoprecipitation-sequencing (m6A-seq) and RNA-seq analyses. We found that global m6A levels increased during tomato fruit expansion from immature green to mature green stage. m6A-seq revealed that thousands of protein-coding genes are m6A-modified mainly in the 3'-untranslated regions. m6A-seq and RNA-seq analyses showed a positive association between m6A methylation and mRNA abundance. In particular, a large number of fruit expansion-related genes involved in hormone responses and endoreduplication were m6A modified and expressed more actively than the non-m6A-modified genes, suggesting a potential role of m6A modification in tomato fruit expansion. Importantly, altering m6A levels by direct injection of 3-deazaneplanocin A (DA; m6A writer inhibitor) or meclofenamic acid (MA; m6A eraser inhibitor) into tomato fruits suppressed fruit expansion; however, injection of exogenous DA or MA accelerated or delayed fruit ripening, respectively. Collectively, these results suggest a dynamic role of m6A methylation in the expansion and ripening of tomato fruits.
N6-甲基腺苷（m6A）是真核信使 RNA 中最丰富的内部修饰。尽管 m6A 在许多生物学过程中发挥了作用，包括胚胎发育、开花时间控制、小孢子发生、果实成熟和应激反应，但它在植物发育的其他方面的贡献仍需要探索。在这里，我们通过平行的 m6A-免疫沉淀测序（m6A-seq）和 RNA-seq 分析，展示了 m6A 沉积与番茄（Solanum lycopersicum）果实扩张之间的潜在联系。我们发现，从不成熟的绿色到成熟的绿色阶段，番茄果实扩张过程中全局 m6A 水平增加。m6A-seq 显示，数千个蛋白编码基因主要在 3'-非翻译区被 m6A 修饰。m6A-seq 和 RNA-seq 分析表明，m6A 甲基化与 mRNA 丰度之间存在正相关。特别是，大量与激素反应和核内有丝分裂有关的与果实扩张相关的基因被 m6A 修饰，并且比非 m6A 修饰的基因表达更活跃，这表明 m6A 修饰在番茄果实扩张中可能发挥作用。重要的是，通过直接向番茄果实中注射 3-去氮杂胞苷 A（DA；m6A 写入抑制剂）或甲氯芬酸（MA；m6A 橡皮擦抑制剂）来改变 m6A 水平会抑制果实扩张；然而，分别注射外源性 DA 或 MA 会加速或延迟果实成熟。总的来说，这些结果表明 m6A 甲基化在番茄果实扩张和成熟中具有动态作用。
