Integrated Proteomics and Metabolomics Analysis Provides Insights into Ganoderic Acid Biosynthesis in Response to Methyl Jasmonate in Ganoderma Lucidum.

Ganoderma lucidum is widely recognized as a medicinal basidiomycete. It was previously reported that the plant hormone methyl jasmonate (MeJA) could induce the biosynthesis of ganoderic acids (GAs), which are the main active ingredients of G. lucidum. However, the regulatory mechanism is still unclear. In this study, integrated proteomics and metabolomics were employed on G. lucidum to globally identify differences in proteins and metabolites under MeJA treatment for 15 min (M15) and 24 h (M24). Our study successfully identified 209 differential abundance proteins (DAPs) in M15 and 202 DAPs in M24. We also identified 154 metabolites by GC-MS and 70 metabolites by LC-MS in M24 that are involved in several metabolic pathways. With an in-depth analysis, we found some DAPs and metabolites that are involved in the oxidoreduction process, secondary metabolism, energy metabolism, transcriptional and translational regulation, and protein synthesis. In particular, our results reveal that MeJA treatment leads to metabolic rearrangement that inhibited the normal glucose metabolism, energy supply, and protein synthesis of cells but promoted secondary metabolites, including GAs. In conclusion, our proteomics and metabolomics data further confirm the promoting effect of MeJA on the biosynthesis of GAs in G. lucidum and will provide a valuable resource for further investigation of the molecular mechanisms of MeJA signal response and GA biosynthesis in G. lucidum and other related species.

Proteomic analysis of rice leaves shows the different regulations to osmotic stress and stress signals.

Following the idea of partial root-zone drying (PRD) in crop cultivation, the morphological and physiological responses to partial root osmotic stress (PROS) and whole root osmotic stress (WROS) were investigated in rice. WROS caused stress symptoms like leaf rolling and membrane leakage. PROS stimulated stress signals, but did not cause severe leaf damage. By proteomic analysis, a total of 58 proteins showed differential expression after one or both treatments, and functional classification of these proteins suggests that stress signals regulate photosynthesis, carbohydrate and energy metabolism. Two other proteins (anthranilate synthase and submergence-induced nickel-binding protein) were upregulated only in the PROS plants, indicating their important roles in stress resistance. Additionally, more enzymes were involved in stress defense, redox homeostasis, lignin and ethylene synthesis in WROS leaves, suggesting a more comprehensive regulatory mechanism induced by osmotic stress. This study provides new insights into the complex molecular networks within plant leaves involved in the adaptation to osmotic stress and stress signals.