腋芽是植物形态学的一个重要方面,有助于最终的烟草产量。然而,烟草中腋芽发育的机制仍然未知。为了研究烟草生物学的这一方面,比较了打顶前后腋芽的代谢组和蛋白质组。在打顶前和打顶后1、3和5天,共有569种代谢物差异丰富。KEGG分析进一步表明,腋芽的特征是与类黄酮代谢有关的代谢物的惊人富集,表明打顶后烟草腋芽中具有很强的类黄酮生物合成活性。此外,在打顶前和打顶后1、3和5天鉴定了9035种差异表达的蛋白质(DEP)。随后的GO和KEGG分析显示,腋芽中的DEP富含氧化应激,激素信号转导,MAPK信号通路,以及淀粉和蔗糖的代谢。整合的蛋白质组和代谢组分析显示,芽中吲哚-3-乙酸(IAA)的变化通过调节参与碳水化合物代谢的蛋白质来控制腋芽的休眠释放和持续生长,氨基酸代谢,和脂质代谢。值得注意的是,与活性氧(ROS)清除和类黄酮生物合成相关的蛋白质与IAA含量呈负相关。这些发现揭示了IAA改变在调节腋芽生长中的关键作用,并暗示了IAA改变之间的潜在串扰,ROS稳态,打顶胁迫下烟草腋芽中类黄酮的生物合成,这可以提高我们对腋芽中IAA变化作为腋芽发育的重要调节剂的认识。
Axillary bud is an important aspect of plant morphology, contributing to the final tobacco yield. However, the mechanisms of axillary bud development in tobacco remain largely unknown. To investigate this aspect of tobacco biology, the metabolome and
proteome of the axillary buds before and after topping were compared. A total of 569 metabolites were differentially abundant before and 1, 3, and 5 days after topping. KEGG analyses further revealed that the axillary bud was characterized by a striking enrichment of metabolites involved in flavonoid metabolism, suggesting a strong flavonoid biosynthesis activity in the tobacco axillary bud after topping. Additionally, 9035 differentially expressed proteins (DEPs) were identified before and 1, 3, and 5 days after topping. Subsequent GO and KEGG analyses revealed that the DEPs in the axillary bud were enriched in oxidative stress, hormone signal transduction, MAPK signaling pathway, and starch and sucrose metabolism. The integrated
proteome and metabolome analysis revealed that the indole-3-acetic acid (IAA) alteration in buds control dormancy release and sustained growth of axillary bud by regulating proteins involved in carbohydrate metabolism, amino acid metabolism, and lipid metabolism. Notably, the proteins related to reactive oxygen species (ROS) scavenging and flavonoid biosynthesis were strongly negatively correlated with IAA content. These findings shed light on a critical role of IAA alteration in regulating axillary bud outgrowth, and implied a potential crosstalk among IAA alteration, ROS homeostasis, and flavonoid biosynthesis in tobacco axillary bud under topping stress, which could improve our understanding of the IAA alteration in axillary bud as an important regulator of axillary bud development.