Zeng Zhebin, Li Yawei, Zhu Man, Wang Xiaoyao, Wang Yan, Li Ang, Chen Xiaoya, Han Qianrong, Nieuwenhuizen Niels J, Ampomah-Dwamena Charles, Deng Xiuxin, Cheng Yunjiang, Xu Qiang, Xiao Cui, Zhang Fan, Atkinson Ross G, Zeng Yunliu
National Key Laboratory for Germplasm Innovation & Utilization of Horticultural Crops, Joint International Research Laboratory of Germplasm Innovation & Utilization of Horticultural Crops, National R&D Centre for Citrus Preservation, College of Horticulture and Forestry Science, Huazhong Agricultural University, Wuhan 430070, P.R. China.
College of Horticulture, Xinyang Agriculture and Forestry University, Xinyang 464000, P.R. China.
Plant Physiol. 2024 Dec 23;197(1). doi: 10.1093/plphys/kiae567.
Kiwifruit (Actinidia chinensis), a recently commercialized horticultural crop, is rich in various nutrient compounds. However, the regulatory networks controlling the dynamic changes in key metabolites among different tissues remain largely unknown. Here, high-resolution spatiotemporal datasets obtained by ultraperformance liquid chromatography-tandem mass spectrometry methodology and RNA-seq were employed to investigate the dynamic changes in the metabolic and transcriptional landscape of major kiwifruit tissues across different developmental stages, including from fruit skin, outer pericarp, inner pericarp, and fruit core. Kiwifruit spatiotemporal regulatory networks (KSRN) were constructed by integrating the 1,243 identified metabolites and co-expressed genes into 10 different clusters and 11 modules based on their biological functions. These networks allowed the generation of a global map for the major metabolic and transcriptional changes occurring throughout the life cycle of different kiwifruit tissues and discovery of the underlying regulatory networks. KSRN predictions confirmed previously established regulatory networks, including the spatiotemporal accumulation of anthocyanin and ascorbic acid (AsA). More importantly, the networks led to the functional characterization of three transcription factors: an A. chinensis ethylene response factor 1, which negatively controls sugar accumulation and ethylene production by perceiving the ripening signal, a basic-leucine zipper 60 (AcbZIP60) transcription factor, which is involved in the biosynthesis of AsA as part of the L-galactose pathway, and a transcription factor related to apetala 2.4 (RAP2.4), which directly activates the expression of the kiwi fruit aroma terpene synthase gene AcTPS1b. Our findings provide insights into spatiotemporal changes in kiwifruit metabolism and generate a valuable resource for the study of metabolic regulatory processes in kiwifruit as well as other fruits.
猕猴桃（中华猕猴桃）是一种最近商业化种植的园艺作物，富含多种营养化合物。然而，控制不同组织中关键代谢物动态变化的调控网络在很大程度上仍不为人知。在此，我们利用超高效液相色谱-串联质谱法和RNA测序获得的高分辨率时空数据集，研究了猕猴桃主要组织在不同发育阶段（包括果皮、外果皮、内果皮和果核）代谢和转录图谱的动态变化。通过将1243种已鉴定的代谢物和共表达基因根据其生物学功能整合到10个不同的簇和11个模块中，构建了猕猴桃时空调控网络（KSRN）。这些网络能够生成不同猕猴桃组织整个生命周期中主要代谢和转录变化的全局图谱，并发现潜在的调控网络。KSRN预测证实了先前建立的调控网络，包括花青素和抗坏血酸（AsA）的时空积累。更重要的是，这些网络还对三个转录因子进行了功能表征：一个中华猕猴桃乙烯反应因子1，它通过感知成熟信号负调控糖分积累和乙烯产生；一个碱性亮氨酸拉链60（AcbZIP60）转录因子，它作为L-半乳糖途径的一部分参与AsA的生物合成；以及一个与花瓣发育相关的2.4转录因子（RAP2.4），它直接激活猕猴桃香气萜烯合酶基因AcTPS1b的表达。我们的研究结果为猕猴桃代谢的时空变化提供了见解，并为研究猕猴桃以及其他水果的代谢调控过程提供了宝贵资源。
