Methyl jasmonate differentially and tissue-specifically regulated the expression of arginine catabolism-related genes and proteins in Agaricus bisporus mushrooms during storage.

Methyl jasmonate (MeJA)-regulated postharvest quality retention of Agaricus bisporus fruiting bodies is associated with arginine catabolism. However, the mechanism of MeJA-regulated arginine catabolism in edible mushrooms is still unclear. This study aimed to investigate the regulatory modes of MeJA on the expression of arginine catabolism-related genes and proteins in intact and different tissues of A. bisporus mushrooms during storage. Results showed that exogenous MeJA treatment activated endogenous JA biosynthesis in A. bisporus mushrooms, and differentially and tissue-specifically regulated the expression of arginine catabolism-related genes (AbARG, AbODC, AbSPE-SDH, AbSPDS, AbSAMDC, and AbASL) and proteins (AbARG, AbSPE-SDH, AbASL, and AbASS). MeJA caused no significant change in AbASS expression but resulted in a dramatic increase in AbASS protein level. Neither the expression of the AbSAMS gene nor the AbSAMS protein was conspicuously altered upon MeJA treatment. Additionally, MeJA reduced the contents of arginine and ornithine and induced the accumulation of free putrescine and spermidine, which was closely correlated with MeJA-regulated arginine catabolism-related genes and proteins. Hence, the results suggested that the differential and tissue-specific regulation of arginine catabolism-related genes and proteins by MeJA contributed to their selective involvement in the postharvest continuing development and quality retention of button mushrooms.

Epsilon-poly-l-lysine alleviates brown blotch disease of postharvest Agaricus bisporus mushrooms by directly inhibiting Pseudomonas tolaasii and inducing mushroom disease resistance.

The natural antimicrobial peptide, epsilon-poly-l-lysine (ε-PL), is widely acknowledged as a food preservative. However, its potential in managing bacterial brown blotch disease in postharvest edible mushrooms and the associated mechanism remain unexplored. In this study, concentrations of ε-PL ≥ 150 mg L-1 demonstrated significant inhibition effects, restraining over 80% of growth and killed over 99% of Pseudomonas tolaasii (P. tolaasii). This inhibition effect occurred in a concentration-dependent manner. The in vivo findings revealed that treatment with 150 mg L-1 ε-PL effectively inhibited P. tolaasii-caused brown blotch disease in Agaricus bisporus (A. bisporus) mushrooms. Plausible mechanisms underlying ε-PL's action against P. tolaasii in A. bisporus involve: (i) damaging the cell morphology and membrane integrity, and increasing uptake of propidium iodide and leakage of cellular components of P. tolaasii; (ii) interaction with intracellular proteins and DNA of P. tolaasii; (iii) inhibition of P. tolaasii-induced activation of polyphenol oxidase, elevation of antioxidative enzyme activities, stimulation of phenylpropanoid biosynthetic enzyme activities and metabolite production, and augmentation of pathogenesis-related protein contents in A. bisporus mushrooms. These findings suggest promising prospects for the application of ε-PL in controlling bacterial brown blotch disease in A. bisporus.

A 3R-MYB transcription factor is involved in Methyl Jasmonate-Induced disease resistance in Agaricus bisporus and has implications for disease resistance in Arabidopsis.

INTRODUCTION: Methyl jasmonate (MeJA) and MYB transcription factors (TFs) play important roles in pathogen resistance in several plants, but MYB TFs in conjunction with MeJA-induced defense against Pseudomonas tolaasii in edible mushrooms remain unknown. OBJECTIVES: To investigate the role of a novel 3R-MYB transcription factor (AbMYB11) in MeJA-induced disease resistance of Agaricus bisporus and in the resistance of transgenic Arabidopsis to P. tolaasii. METHODS: Mushrooms were treated with MeJA alone or in combination with phenylpropanoid pathway inhibitors, and the effects of the treatments on the disease-related and physiological indicators of the mushrooms were determined to assess the role of MeJA in inducing resistance and the importance of the phenylpropanoid pathway involved. Subcellular localization, gene expression analysis, dual-luciferase reporter assay, electrophoretic mobility shift assay, and transgenic Arabidopsis experiments were performed to elucidate the molecular mechanism of AbMYB11 in regulating disease resistance. RESULTS: MeJA application greatly improved mushroom resistance to P. tolaasii infection, and suppression of the phenylpropanoid pathway significantly weakened this effect. MeJA treatment stimulated the accumulation of phenylpropanoid metabolites, which was accompanied by increased the activities of biosynthetic enzymes and the expression of phenylpropanoid pathway-related genes (AbPAL1, Ab4CL1, AbC4H1) and an AbPR-like gene, further confirming the critical role of the phenylpropanoid pathway in MeJA-induced responses to P. tolaasii. Importantly, AbMYB11, localized in the nucleus, was rapidly induced by MeJA treatment under P. tolaasii infection; it transcriptionally activated the phenylpropanoid pathway-related and AbPR-like genes, and AbMYB11 overexpression in Arabidopsis significantly increased the transcription of phenylpropanoid-related genes, the accumulation of total phenolics and flavonoids, and improved resistance to P. tolaasii. CONCLUSION: This study clarified the pivotal role of AbMYB11 as a regulator in disease resistance by modulating the phenylpropanoid pathway, providing a novel idea for the breeding of highly disease-resistant edible mushrooms and plants.

Identification of potential diagnostic genes for atherosclerosis in women with polycystic ovary syndrome.

Polycystic ovary syndrome (PCOS), which is the most prevalent endocrine disorder among women in their reproductive years, is linked to a higher occurrence and severity of atherosclerosis (AS). Nevertheless, the precise manner in which PCOS impacts the cardiovascular well-being of women remains ambiguous. The Gene Expression Omnibus database provided four PCOS datasets and two AS datasets for this study. Through the examination of genes originating from differentially expressed (DEGs) and critical modules utilizing functional enrichment analyses, weighted gene co-expression network (WGCNA), and machine learning algorithm, the research attempted to discover potential diagnostic genes. Additionally, the study investigated immune infiltration and conducted gene set enrichment analysis (GSEA) to examine the potential mechanism of the simultaneous occurrence of PCOS and AS. Two verification datasets and cell experiments were performed to assess biomarkers' reliability. The PCOS group identified 53 genes and AS group identified 175 genes by intersecting DEGs and key modules of WGCNA. Then, 18 genes from two groups were analyzed by machine learning algorithm. Death Associated Protein Kinase 1 (DAPK1) was recognized as an essential gene. Immune infiltration and single-gene GSEA results suggest that DAPK1 is associated with T cell-mediated immune responses. The mRNA expression of DAPK1 was upregulated in ox-LDL stimulated RAW264.7 cells and in granulosa cells. Our research discovered the close association between AS and PCOS, and identified DAPK1 as a crucial diagnostic biomarker for AS in PCOS.

Low muscle mass is associated with efficacy of biologics in Crohn's disease.

BACKGROUND: Low muscle mass (LMM) can be a frequent complication in Crohn's disease (CD). We attempted to explore the effect of LMM on the efficacy of biologics in patients with CD. METHODS: The retrospective cohort study included moderate-to-severe CD patients treated with infliximab or ustekinumab, and appendicitis patients as control. The skeletal muscle area (SMA) of L3 was assessed to evaluate the patients' muscle mass. After propensity score matching, the impact of LMM on drug efficacy was assessed in CD patients. RESULTS: A total of 269 patients with CD and 172 appendicitis patients were included. The CD group had lower skeletal muscle density and BMI, and a higher risk of developing LMM than the control group. BMI (OR = 0.48, p < 0.001) and previous use of biologics (OR = 2.94, p = 0.019) were found to be independently associated with LMM. LMM was found to be associated with a decrease in clinical response (at weeks 8-14), clinical remission (at weeks 8-14, 24-30 and 52) and biochemical remission (at week 52). At weeks 24-30 and 52, LMM was independently associated with loss of response (LOR). We found LMM could be a predictor of lower clinical remission at week 30, lower clinical remission at week 52 and a higher LOR rate at week 30 in infliximab. While in ustekinumab, LMM was associated with lower endoscopic remission at week 24, biochemical remission at week 52 and a higher LOR rate at weeks 24 and 52. CONCLUSIONS: The prevalence of LMM was higher in the CD group compared to the control group. For CD patients with LMM, the efficacy of infliximab and ustekinumab was relatively poor in both the short-term and long-term.