Zhang Kaijing, Yang Dekun, Hu Yuchao, Njogu Martin Kagiki, Qian Jingjing, Jia Li, Yan Congsheng, Li Ziang, Wang Xing, Wang Liping
College of Agriculture, Anhui Science and Technology University, Chuzhou 233100, China.
Department of Plant Science, Chuka University, Chuka P.O. Box 109-60400, Kenya.
Plants (Basel). 2022 Aug 28;11(17):2229. doi: 10.3390/plants11172229.
Purple leaf veins and leaf edge cracks comprise the typical leaf phenotype of ; however, the molecular mechanisms and metabolic pathways of the formation of purple leaf veins and leaf edge cracks remain unclear. In this study, transcriptome and metabolome analyses were conducted to explore the regulation pathway of purple leaf vein and leaf edge crack formation based on four mustard samples that showed different leaf colors and degrees of cracking. The results showed genes with higher expression in purple leaf veins were mainly enriched in the flavonoid biosynthesis pathway. Integrating related genes and metabolites showed that the highly expressed genes of (, , and ) and the excessive accumulation of dihydrokaempferol and dihydroquercetin contributed to the purple leaf veins by activating the synthetic pathways of pelargonidin-based anthocyanins and delphinidin-based anthocyanins. Meanwhile, "alpha-farnesene synthase activity" and "glucan endo-1, 3-beta-D-glucosidase activity" related to the adversity were mainly enriched in the serrated and lobed leaves, indicating that the environmental pressure was the dominant factor controlling the change in leaf shape. Overall, these results provided new insights into the regulation pathways for formation of purple leaf veins and leaf edge cracks, which could better accelerate the theoretical research on purple leaf vein color and leaf edge cracks in mustard.
紫色叶脉和叶缘裂纹构成了其典型的叶片表型；然而，紫色叶脉和叶缘裂纹形成的分子机制和代谢途径仍不清楚。在本研究中，基于四个具有不同叶色和开裂程度的芥菜样本，进行了转录组和代谢组分析，以探索紫色叶脉和叶缘裂纹形成的调控途径。结果表明，在紫色叶脉中高表达的基因主要富集在类黄酮生物合成途径中。整合相关基因和代谢产物表明，（，，和）的高表达基因以及二氢山奈酚和二氢槲皮素的过量积累通过激活基于天竺葵素的花青素和基于飞燕草素的花青素的合成途径，促成了紫色叶脉的形成。同时，与逆境相关的“α-法尼烯合酶活性”和“葡聚糖内切-1,3-β-D-葡萄糖苷酶活性”主要富集在锯齿状和浅裂叶片中，表明环境压力是控制叶片形状变化的主导因素。总体而言，这些结果为紫色叶脉和叶缘裂纹形成的调控途径提供了新的见解，这可以更好地加速芥菜中紫色叶脉颜色和叶缘裂纹的理论研究。
