Volvariella volvacea (V. volvacea), commonly referred to as Chinese (paddy straw) mushroom, is a basidiomycete with a protein-rich volva and pileus. Selecting appropriate reference genes is a crucial step in the normalization of quantitative real-time PCR data. Therefore, 12 candidate reference genes were selected from the V. volvacea transcriptome based on previous studies and then BestKeeper, geNorm, and NormFinder were used to identify reference genes stably expressed during different developmental stages and conditions. Of the 12 candidate reference genes, SPRY domain protein (SPRYp), alpha-tubulin (TUBα), cyclophilin (CYP), L-asparaginase (L-asp), and MSF1-domain-containing protein (MSF1) were the most stably expressed under different experimental conditions, while 18S ribosomal RNA (18S), 28S ribosomal RNA (28S), and beta-actin (ACTB) were the least stably expressed. This investigation not only revealed potential factors influencing the suitability of reference genes, but also identified optimal reference genes from a pool of candidate genes under a wide range of conditions.
Light-induced brown film (BF) formation by the vegetative mycelium of Lentinula edodes is important for ensuring the quantity and quality of this edible mushroom. Nevertheless, the molecular mechanism underlying this phenotype is still unclear. In this study, a comparative proteomic analysis of mycelial BF formation in L. edodes was performed. Seventy-three protein spots with at least a twofold difference in abundance on two-dimensional electrophoresis (2DE) maps were observed, and 52 of them were successfully identified by matrix-assisted laser desorption/ionization tandem time-of-flight mass spectrometry (MALDI-TOF/TOF/MS). These proteins were classified into the following functional categories: small molecule metabolic processes (39%), response to oxidative stress (5%), and organic substance catabolic processes (5%), followed by oxidation-reduction processes (3%), single-organism catabolic processes (3%), positive regulation of protein complex assembly (3%), and protein metabolic processes (3%). Interestingly, four of the proteins that were upregulated in response to light exposure were nucleoside diphosphate kinases. To our knowledge, this is the first proteomic analysis of the mechanism of BF formation in L. edodes. Our data will provide a foundation for future detailed investigations of the proteins linked to BF formation.
6 May 2019 in Oxidative Medicine and Cellular Longevity
Fungal immunomodulatory proteins (FIPs) are a class of small proteins that have been extensively studied for their immunomodulatory activities. In this study, two novel FIPs from Lentinus tigrinus were identified and named Fip-lti1 and Fip-lti2. The bioactive characteristics of Fip-lti1 and Fip-lti2 were compared to a well-known FIP (LZ-8 from Ganoderma lucidum) to investigate the effect of Fip-lti1 and Fip-lti2 expression on concanavalin A- (Con A-) induced liver oxidative injury. Both Fip-lti1 and Fip-lti2 protected the livers from Con A-induced necrosis, as evidenced by decreased serum aminotransferase levels (AST, ALT) and relieved liver histology. Levels of proinflammatory cytokines (TNF-α, IL-1β, and IL-6) and oxidative stress (SOD, MDA) were shown to be reduced by expressing Fip-lti1 and Fip-lti2. In addition, the hepatoprotective effect of Fip-lti1, Fip-lti2, and LZ-8 correlated with ameliorating the imbalance of Th1/Th2 (IFN-γ/IL-4). The observed liver protection of Fip-lti1 and Fip-lti2 was mechanistically explored. Treatments with Fip-lti1 and Fip-lti2 regulated GATA3/T-bet expression, activated the decreased Nrf-2/HO-1 pathway, and countered the upregulated NLRP3/ASC/NF-κBp65 signaling in Con A-stimulated liver injury. Nrf2 activation was shown to be involved in the mechanisms underlying the protection of Fip-lti by RNA interference. In conclusion, we identified two new fungal proteins (Fip-lti1 and Fip-lti2) that can protect the liver from Con A-induced liver oxidative injury through the Nrf2/NF-κB/NLRP3/IL-1β pathway.
Pleurotus eryngii is a tasty and low-calorie mushroom containing abundant high-quality protein. This study aims to improve the digestibility of P. eryngii protein (PEP) and hence to facilitate its development as a healthy alternative protein. The extracted PEP was pretreated with 1000–5000 U of papain, neutral protease and alkaline protease. The Chyme collected from in vitro simulated gastrointestinal digestion was analyzed by fluorescence microscopy and protein particle analyzer, and the endpoint profiles of peptides and amino acids were determined by UHPLC-MS/MS and NanoLC-MS/MS. The particle size curve and fluorescence microscopy images jointly supported that protease hydrolysis improved decomposition and dispersion of PEP during digestion, particularly in the gastric phase. The impact on Zeta potential was minimal. Proteases effectively increased the abundance of amino acids after digestion, particularly L-isomer Lys and Arg Maximum release was achieved when pretreated with 5000 U of alkaline protease, reaching 7.54 times that of control. Pretreatments by proteases also notably increased digestive yields of 16,736–19,870 peptides, with the maximum reaching 1.70 times that of the control, which mainly consisted of small peptides composed of 7–15 amino acids with molecular weight below 800 Da. The findings indicated that protease hydrolysis, especially pretreatment with 5000 U of alkaline protease, effectively enhanced the digestibility of PEP, which shed light on providing enzymatic approaches for improving bioavailability and developing healthy fungal proteins.
DNA methylation, a cornerstone of epigenetic regulation, governs critical biological processes including transcriptional modulation, genomic imprinting, and transposon suppression through chromatin architecture remodeling. Recent advances have revealed that aberrant methylation patterns—characterized by spatial-temporal dysregulation and stochastic molecular noise—serve as key drivers of diverse pathological conditions, from oncogenesis to neurodegenerative disorders. However, the field faces dual challenges: (1) current understanding remains fragmented due to the inherent spatiotemporal heterogeneity of methylation landscapes across tissues and developmental stages, and (2) mechanistic insights into non-canonical methylation pathways (particularly 6mA) in non-mammalian systems are conspicuously underdeveloped. This review systematically synthesizes the evolutionary-conserved versus species-specific features of 5-methylcytosine (5mC) and N6-methyladenine (6mA) regulatory networks across three biological kingdoms. Through comparative analysis of methylation/demethylation enzymatic cascades (DNMTs/TETs in mammals, CMTs/ROS1 in plants, and DIM-2/DNMTA in fungi), we propose a unified framework for targeting methylation-associated diseases through precision epigenome editing, while identifying critical knowledge gaps in fungal methylome engineering that demand urgent investigation.