To clarify the physiological mechanism of the Lentinula edodes (L. edodes) response to high-temperature stress, two strains of L. edodes with different tolerances were tested at different durations of high temperature, and the results showed that there were significant changes in their phenotypes and physiology. To further explore the response mechanism, we established a targeted GC–MS-based metabolomics workflow comprising a standardized experimental setup for growth, treatment and sampling of L. edodes mycelia, and subsequent GC–MS analysis followed by data processing and evaluation of quality control (QC) measures using tailored statistical and bioinformatic tools. This study identified changes in the L. edodes mycelial metabolome following different time treatments at high temperature based on nontargeted metabolites with GC-MS and further adopted targeted metabolomics to verify the results of the analysis. After multiple statistical analyses were carried out using SIMCA software, 74 and 108 differential metabolites were obtained, respectively. Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis showed that the metabolic pathways with significant changes included those related to the following: amino acid metabolism, the glycolysis pathway, the tricarboxylic acid (TCA) cycle, and sugar metabolism. Most amino acids and carbohydrates enriched in these metabolic pathways were upregulated in strain 18, downregulated in strain 18N44, or the synthesis in strain 18 was higher than that in strain 18N44. This result was consistent with the physiological phenotypic characteristics of the two strains under high-temperature stress and revealed the reason why strain 18N44 was more heat-sensitive. At the same time, under high temperature, the decrease of intermediate products in glycolysis and the TCA cycle resulted in carbon starvation and insufficient energy metabolism, thus inhibiting the growth of L. edodes. In addition, the results also showed that the metabolites produced by different L. edodes strains under high-temperature stress were basically the same. However, different strains had species specificity, so the changes in the content of metabolites involved in the response to high-temperature stress were different. This provides a theoretical basis for further understanding the mechanism of the L. edodes response to high temperature and can be used to establish an evaluation system of high-temperature-resistant strains and lay the foundation for molecular breeding of new L. edodes strains resistant to high temperature.

Floccularia luteovirens, a rare wild edible and medicinal fungus, is endemic to the Tibetan plateau. However, attempts to artificially domesticate this species have not been successful, resulting in extremely limited utilization of this valuable resource. This paper presents the geographical distribution of F. luteovirens, along with its ecological and biological characteristics. It explores population relations, symbiotic relationships, soil microbial community relations, fruiting body occurrence conditions, nutritional metabolism, and reproductive patterns. The cultivation techniques, as well as the edible and medicinal value of this mushroom, are also reviewed. Through an overall analysis of the physiological characteristics and current research status of F. luteovirens, the paper discusses its development prospects. The aim is to provide a reference for other researchers and promote its artificial domestication, resource development, and utilization.

Lentinula edodes, one of the most highly regarded edible mushrooms in China, is susceptible to damage from high temperatures. However, a mutant strain derived from L. edodes, known as Le023M, has shown exceptional thermotolerance. Compared to the original strain Le023, Le023M exhibited accelerated mycelial recovery following heat stress. Through RNA-seq analysis, the majority of differentially expressed genes (DEGs) were found to be associated with functions such as “protein refolding”, “protein unfolding”, “protein folding”, and “response to heat”, all of which are closely linked to heat shock proteins. Furthermore, qRT-PCR results revealed significant accumulation of heat shock-related genes in Le023M under heat stress. GC-MS analysis indicated elevated levels of trehalose, aspartate, and glutamate in Le023M when subjected to heat stress. The highly expressed genes involved in these metabolic pathways were predominantly found in Le023M. Collectively, these findings highlight the following: (i) the crucial role of heat shock proteins (HSPs) in the thermo-resistant mechanisms of Le023M; (ii) the potential of trehalose accumulation in Le023M to enhance mycelium resistance to heat stress; and (iii) the induction of aspartate and glutamate accumulation in response to heat stress. These results shed light on the molecular mechanisms underlying the thermotolerance of Le023M, providing valuable insights for further understanding and improving heat stress response in L. edodes. The findings also highlight the potential applications of Le023M in the cultivation and production of L. edodes under high-temperature conditions.

The postharvest storage of Volvariella volvacea is an important factor limiting the industry development. Low-temperature storage is the traditional storage method used for most edible fungi, but V. volvacea undergoes autolysis at low temperature. To understand the molecular mechanism underlying the low-temperature autolysis of V. volvacea after harvesting, fruiting bodies of V. volvacea strain V23 were stored at 4 °C. Based on our previous study, in which the changes of morphological and physiological indexes during storage for 0, 6, 12, 24, 30, 36, 48 and 60 h were measured; four time points, namely, 0, 12, 24 and 60 h, were selected for this differential proteomics study. The proteomic changes in the postharvest storage samples were studied by isobaric tags for relative and absolute quantification-coupled two-dimensional liquid chromatography-tandem mass spectrometry (2D LC–MS/MS). A total of 2,063 proteins were identified, and 192 differentially expressed proteins (DEPs), including 24 up-regulated proteins and 168 down-regulated proteins, were detected after 12 h of storage. After 24 h of storage, 234 DEPs, including 48 up-regulated and 186 down-regulated proteins, were observed, and after 60 h, 415 DEPs, including 65 up-regulated proteins and 350 down-regulated proteins, were observed. An in-depth data analysis showed that the DEPs participated in various cellular processes, particularly metabolic processes. In this study, we combined Gene Ontology and Kyoto Encyclopedia of Genes and Genomes pathway analyses, and the results focused on oxidative phosphorylation and ubiquitin mediated proteolysis pathways. In addition, sdh2, uba1 and ubc1 was confirmed by quantitative real-time polymerase chain reaction, and the results showed that the expression of these genes were consistent with their protein level. Based on the literature and our results, it is speculated that the identified DEPs, such as ATP1, SDH2, COR1, UBA1, COX4, UBC1 and SKP1 play a key role in the low-temperature autolysis of V. volvacea.

Lentinula edodes (L. edodes), one of the most popular edible mushrooms in China, is adversely affected by high temperature. Heat shock proteins (HSPs) play a crucial role in regulating the defense responses against the abiotic stresses in L. edodes. Some HSPs in L. edodes have been described previously, but a genome-wide analysis of these proteins is still lacking. Here, the HSP genes across the entire genome of the L. edodes mushroom were identified. The 34 LeHSP genes were subsequently classified into six subfamilies according to their molecular weights and the phylogenetic analysis. Sequence analysis showed that LeHSP proteins from the same subfamily have conserved domains and one to five similar motifs. Except for Chr 5 and 9, 34 LeHSPs genes were distributed on the other eight chromosomes. Three pairs of paralogs were identified because of sequence alignment and were confirmed as arising from segmental duplication. In LeHSPs’ promoters, different numbers of heat shock elements (HSEs) were predicted. The expression profiles of LeHSPs in 18N44 and 18 suggested that the thermo-tolerance of strain 18N44 might be related to high levels of LeHSPs transcript in response to heat stress. The quantitative real-time PCR (qRT-PCR) analysis of the 16 LeHSP genes in strains Le015 and Le027 verified their stress-inducible expression patterns under heat stress. Therefore, these comprehensive findings provide useful in-depth information on the evolution and function of LeHSPs and lay a theoretical foundation in breeding thermotolerant L. edodes varieties.

Floccularia luteovirens is one of the rare edible fungi with high nutritional value found on the Qinghai-Tibet Plateau. However, research at the molecular level on this species is currently constrained due to the lack of reliable reference genes for this species. Thirteen potential reference genes (ACT, GAPDH, EF-Tu, SAMDC, UBI, CLN1, β-TUB, γ-TUB, GTP, H3, UBC, UBC-E2, and GTPBP1) were chosen for the present study, and their expression under various abiotic conditions was investigated. Stability of gene expression was tested using GeNorm, NormFinder, BestKeeper, Delta-Ct, and RefFinder. The results showed that the most suitable reference genes for salt treatment were ACT and EF-Tu. Under drought stress, γ-TUB and UBC-E2 would be suitable for normalization. Under oxidative stress, the reference genes H3 and GAPDH worked well. Under heat stress, the reference genes EF-Tu and γ-TUB were suggested. Under extreme pH stress, UBC-E2 and H3 were appropriate reference genes. Under cadmium stress, the reference genes ACT and UBC-E2 functioned well. In different tissues, H3 and GTPBP1 were appropriate reference genes. The optimal internal reference genes when analyzing all samples were H3 and SAMDC. The expression level of HSP90 was studied to further validate the applicability of the genes identified in this study.