Comparative transcriptomic and proteomic analyses to determine the lignin synthesis pathway involved in the fungal stress response in Panax notoginseng

Abstract

Plants are constantly threatened by various pathogens in challenging environments. Alternaria panax Whetzel is a destructive pathogen that affects many plants, including Panax notoginseng, and significantly reduces the yield and product quality of P. notoginseng. However, there are few studies on the response of P. notoginseng to the oxidative stress caused by A. panax infection. By exploiting the advantages of advanced transcriptomic and proteomic technologies, we studied the response of P. notoginseng to A. panax stress. Fungal infection caused significant changes in the P. notoginseng transcriptome and proteome relative to the control. We found many candidate transcripts/proteins that may be involved in lignin synthesis during the activation of oxidative stress in P. notoginseng. The expression of many genes and proteins was induced or inhibited by the fungus, for example, the expression levels of the PAL, 4CL, COMT, CAD and POX genes in the lignin synthesis pathway increased significantly after fungal inoculation. In addition, the levels of the products of the lignin synthesis pathway increased significantly after A. panax inoculation. This indicates that the fungus activates the oxidative stress response in P. notoginseng.