An RNA-chaperone-like protein stabilizes 3ʹ processed transcripts of photosynthetic electron transfer B (petB) and stimulates the translation of petD and petA i
Sinomenine is the main component of the vine Sinomenium acutum. It was first isolated in the early 1920s and has since attracted special interest as a potential anti-rheumatoid arthritis (RA) agent, owing to its successful application in traditional Chinese medicine for the treatment of neuralgia and rheumatoid diseases. In the past few decades, significant advances have broadened our understanding of the molecular mechanisms through which sinomenine treats RA, as well as the structural modifications necessary for improved pharmacological activity. In this review, we summarize up-to-date reports on the pharmacological properties of sinomenine in RA treatment, document their underlying mechanisms, and provide an overview of promising sinomenine derivatives as potential RA drug therapies.
Chlorophyll biosynthesis must be tightly coupled to light-harvesting chlorophyll a/b-binding protein (LHCP) biogenesis, as free chlorophyll and its precursors are phototoxic. However, precisely how these 2 processes are coordinated in Arabidopsis (Arabidopsis thaliana) remains elusive. Our previous studies demonstrated the role of LHCP TRANSLOCATION DEFECT (LTD) in delivering LHCPs to the chloroplast via the signal recognition particle-dependent pathway. Here, we show that LTD interacts with and stabilizes the chlorophyll biosynthesis enzymes Mg-protoporphyrin methyltransferase and Mg-protoporphyrin monomethylester (MgPME) cyclase, maintaining their activity. We also demonstrate the direct binding of LTD to MgPME, and through crystal structure analysis, we show that the groove of the LTD dimer is critical for MgPME binding. Thus, we propose that LTD transfers MgPME from Mg-protoporphyrin methyltransferase to the MgPME cyclase. These results elucidate a role for LTD in synchronizing chlorophyll biosynthesis with LHCP transport to ensure the correct insertion of chlorophylls into LHCPs.
Ganoderma lucidum spores are widely consumed natural functional materials; however, the influence of sporoderm disruption on the physicochemical characteristics and biological performance of spore polysaccharides remains insufficiently understood. In this study, polysaccharides extracted from intact spores (GLSP-I) and sporoderm-broken spores (GLSP-SB) were systematically compared to clarify how industrial processing affects their physicochemical properties and cytoprotective activity. Chemical characterization demonstrated that sporoderm disruption increased extraction yield and modified molecular weight distribution, monosaccharide composition, and spectroscopic features without fundamentally altering the polysaccharide backbone. Both polysaccharide fractions alleviated TBHP-induced oxidative injury, whereas GLSP-SB exhibited enhanced cytoprotective efficacy. Quantitative proteomic analysis revealed that GLSP-SB regulated a broader set of proteins associated with mitochondrial organization, oxidative stress response, autophagy, and cellular energy metabolism. Functional assays further showed that GLSP-SB promoted mitochondrial biogenesis, restored ATP production, and maintained mitochondrial morphology under oxidative stress conditions. Mechanistic validation demonstrated activation of the SIRT1/AMPK signaling pathway, indicating that modulation of this pathway contributes to mitochondrial adaptive responses. These findings suggest that sporoderm disruption reshapes polysaccharide characteristics and is associated with enhanced mitochondrial protective activity, providing mechanistic insight into the rational processing and functional utilization of G. lucidum spore products.
Sclerotinia sclerotiorum (Lib.) de Bary is a globally distributed necrotrophic fungal pathogen capable of infecting a wide range of crops. While conventional chemical fungicides offer effective control, their long-term use leads to increased fungicide resistance and poses risks to the environment and human health due to pesticide residues, underscoring the urgent need to develop novel fungicides. Artemisinin, first identified in Artemisia annua, is renowned for its antimalarial activity. Here, we demonstrate that artemisinin exhibites effective antifungal activity against Sclerotinia sclerotiorum with an EC50 value of 0.1 mg/mL. Treatment with artemisinin caused the mycelia surface to collapse and shrivel, accompanied by enhanced membrane permeability. Pretreating Brassica napus and Arabidopsis leaves with artemisinin increased resistance to S. sclerotiorum infection. Proteomic analysis revealed that artemisinin treatment markedly downregulated the expression of key functional proteins in S. sclerotiorum, including enzymes involved in oxalic acid biosynthesis, cell wall-associated proteins, and secreted proteins. In conclusion, artemisinin exhibits notable inhibitory effects against S. sclerotiorum and may hold potential for development as a novel fungicide.