Tang Renkun, Duan Xiaoyu, Zhou Leilei, Gao Guangtong, Liu Jinying, Wang Yuying, Shao Xingfeng, Qin Guozheng
State Key Laboratory of Plant Diversity and Specialty Crops, Institute of Botany, Chinese Academy of Sciences, Beijing, 100093, China.
China National Botanical Garden, Beijing, 100093, China.
Nat Commun. 2024 Dec 30;15(1):10912. doi: 10.1038/s41467-024-55294-8.
Fruit ripening is a highly-orchestrated process that requires the fine-tuning and precise control of gene expression, which is mainly governed by phytohormones, epigenetic modifiers, and transcription factors. How these intrinsic regulators coordinately modulate the ripening remains elusive. Here we report the identification and characterization of FvALKBH10B as an N-methyladenosine (mA) RNA demethylase necessary for the normal ripening of strawberry (Fragaria vesca) fruit. FvALKBH10B is induced by phytohormone abscisic acid (ABA), and ABA-Responsive Element Binding Factor 3 (FvABF3), a master regulator in ABA signaling, is responsible for this activation. FvALKBH10B mutation leads to a delay in fruit ripening and causes global mA hypermethylation of 1859 genes. Further analyses show that FvALKBH10B positively modulates the mRNA stability of SEPALLATA3 (FvSEP3) encoding a transcription factor via mA demethylation. In turn, FvSEP3 targets numerous ripening-related genes including those associated with biosynthesis of ABA and anthocyanin and regulates their expression. Our findings uncover an FvABF3-FvALKBH10B-FvSEP3 cascade in controlling fruit ripening in strawberry and provide insights into the complex regulatory networks involved in this process.
果实成熟是一个高度协调的过程，需要对基因表达进行精细调节和精确控制，而基因表达主要受植物激素、表观遗传修饰因子和转录因子的调控。这些内在调节因子如何协同调节果实成熟仍不清楚。在此，我们报告了FvALKBH10B的鉴定和特征，它是一种N-甲基腺苷（mA）RNA去甲基化酶，是草莓（Fragaria vesca）果实正常成熟所必需的。FvALKBH10B由植物激素脱落酸（ABA）诱导，ABA信号通路中的主要调节因子ABA反应元件结合因子3（FvABF3）负责这种激活。FvALKBH10B突变导致果实成熟延迟，并导致1859个基因的整体mA超甲基化。进一步分析表明，FvALKBH10B通过mA去甲基化正向调节编码转录因子的SEPALLATA3（FvSEP3）的mRNA稳定性。反过来，FvSEP3靶向许多与成熟相关的基因，包括那些与ABA和花青素生物合成相关的基因，并调节它们的表达。我们的研究结果揭示了一个在草莓果实成熟控制中起作用的FvABF3-FvALKBH10B-FvSEP3级联，并为这一过程中涉及的复杂调控网络提供了见解。
