背景:芒果(MangiferaindicaL.)生长在海南,广东,云南,四川,福建省和中国的广西自治区。然而,生长在这些地区的树木在冬季遭受严重的寒冷胁迫,影响产量。在这方面,关于叶片的全球代谢组和转录组特征的数据是有限的。这里,我们使用了三个具有不同冷胁迫耐受性的芒果品种的叶片的代谢组和转录组分析,即金黄(J)-耐性,Tainung(T)和GuiremangNo.82(G)-易感,24后(LF),48(MF)和72(HF)小时的冷。
结果:共检测到属于12种化合物类别的1,323种代谢物。其中,氨基酸及其衍生物,核苷酸和衍生物,在三个品种中暴露于冷胁迫后,脂质的积累量较高。值得注意的是,金黄叶黄酮类化合物积累量呈增加趋势,萜类化合物,木脂素和香豆素,和生物碱的暴露时间。在植物激素中,茉莉酸和脱落酸水平下降,而N6-异戊烯基腺嘌呤随冷应激时间的增加而增加。转录组分析导致鉴定了22,526个差异表达基因。许多基因富含光合作用,天线蛋白,类黄酮,在鸡黄叶中,萜类化合物(二和倍半萜)和生物碱生物合成途径被上调。此外,与植物激素相关的表达变化,MAPK(包括钙和H2O2),ICE-CBF-COR信号级联表明这些途径参与冷应激反应。
结论:芒果叶片的冷胁迫耐受性与初级和次级代谢产物生物合成途径的调节有关。茉莉酸,脱落酸,细胞分裂素是芒果叶片冷胁迫反应的潜在调节因子。
BACKGROUND: Mango (Mangifera indica L.) is grown in Hainan, Guangdong, Yunnan, Sichuan, and Fujian provinces and Guanxi autonomous region of China. However, trees growing in these areas suffer severe cold stress during winter, which affects the yield. To this regard, data on global metabolome and transcriptome profiles of leaves are limited. Here, we used combined metabolome and transcriptome analyses of leaves of three mango cultivars with different cold stress tolerance, i.e. Jinhuang (J)-tolerant, Tainung (T) and Guiremang No. 82 (G)-susceptible, after 24 (LF), 48 (MF) and 72 (HF) hours of cold.
RESULTS: A total of 1,323 metabolites belonging to 12 compound classes were detected. Of these, amino acids and derivatives, nucleotides and derivatives, and lipids accumulated in higher quantities after cold stress exposure in the three cultivars. Notably, Jinhuang leaves showed increasing accumulation trends of flavonoids, terpenoids, lignans and coumarins, and alkaloids with exposure time. Among the phytohormones, jasmonic acid and abscisic acid levels decreased, while N6-isopentenyladenine increased with cold stress time. Transcriptome analysis led to the identification of 22,526 differentially expressed genes. Many genes enriched in photosynthesis, antenna proteins, flavonoid, terpenoid (di- and sesquiterpenoids) and alkaloid biosynthesis pathways were upregulated in Jihuang leaves. Moreover, expression changes related to phytohormones, MAPK (including calcium and H2O2), and the ICE-CBF-COR signalling cascade indicate involvement of these pathways in cold stress responses.
CONCLUSIONS: Cold stress tolerance in mango leaves is associated with regulation of primary and secondary metabolite biosynthesis pathways. Jasmonic acid, abscisic acid, and cytokinins are potential regulators of cold stress responses in mango leaves.