Hasan Mahbub, Nishat Zakia Sultana, Hasan Md Soyib, Hossain Tanvir, Ghosh Ajit
Department of Biochemistry and Molecular Biology, Shahjalal University of Science and Technology, Sylhet 3114, Bangladesh.
Biochem Biophys Rep. 2024 Mar 12;38:101677. doi: 10.1016/j.bbrep.2024.101677. eCollection 2024 Jul.
Eukaryotic messenger RNAs (mRNAs) transcend their predominant function of protein encoding by incorporating auxiliary components that ultimately contribute to their processing, transportation, translation, and decay. In doing so, additional layers of modifications are incorporated in mRNAs at post-transcriptional stage. Among them, N6-methyladenosine (mA) is the most frequently found mRNA modification that plays crucial roles in plant development and stress response. In the overall mechanism of mA methylation, key proteins classified based on their functions such as writers, readers, and erasers dynamically add, read, and subtract methyl groups respectively to deliver relevant functions in response to external stimuli. In this study, we identified 30 mA regulatory genes (9 writers, 5 erasers, and 16 readers) in rice that encode 53 proteins (13 writers, 7 erasers, and 33 readers) where segmental duplication was found in one writer and four reader gene pairs. Reproductive cells such as sperm, anther and panicle showed high levels of expression for most of the mA regulatory genes. Notably, writers like , , and showed varied responses in different stress and infection contexts, with initial upregulation in response to early exposure followed by downregulation later. , a noteworthy eraser, displayed varied expression in response to different stresses at different time intervals, but upregulation in certain infections. Reader genes like , , and showed continuous upregulation in exertion of all kinds of stress relevant here. Conversely, other reader genes along with and were observed to be consistently downregulated. The apparent correlation between the expression patterns of mA regulatory genes and stress modulation pathways in this study underscores the need for additional research to unravel their intricate regulatory mechanisms that could ultimately contribute to the substantial development of enhanced stress tolerance in rice through mRNA modification.
真核生物信使核糖核酸（mRNA）通过整合辅助成分超越了其主要的蛋白质编码功能，这些辅助成分最终有助于其加工、运输、翻译和降解。在此过程中，转录后阶段的mRNA会整合额外的修饰层。其中，N6-甲基腺苷（mA）是最常见的mRNA修饰，在植物发育和应激反应中起关键作用。在mA甲基化的整体机制中，根据其功能分类的关键蛋白，如写入器、读取器和擦除器，分别动态地添加、读取和去除甲基基团，以响应外部刺激发挥相关功能。在本研究中，我们在水稻中鉴定出30个mA调控基因（9个写入器、5个擦除器和16个读取器），它们编码53种蛋白质（13个写入器、7个擦除器和33个读取器），其中在一个写入器和四对读取器基因对中发现了片段重复。精子、花药和穗等生殖细胞中大多数mA调控基因表达水平较高。值得注意的是，如 、 和 等写入器在不同的应激和感染情况下表现出不同的反应，早期暴露时先上调，随后下调。值得注意的擦除器 在不同时间间隔对不同应激表现出不同的表达，但在某些感染中上调。如 、 和 等读取器基因在各种相关应激作用下持续上调。相反，观察到其他读取器基因以及 和 持续下调。本研究中mA调控基因的表达模式与应激调节途径之间的明显相关性强调了需要进一步研究以揭示其复杂的调控机制，这些机制最终可能通过mRNA修饰为水稻增强应激耐受性的实质性发展做出贡献。
