The fungal secretory peptide micasin induces itch by activating MRGPRX1/C11/A1 on peripheral neurons.

Pruritus is the leading symptom of dermatophytosis. Microsporium canis is one of the predominant dermatophytes causing dermatophytosis. However, the pruritogenic agents and the related molecular mechanisms of the dermatophyte M. canis remain poorly understood. Here, the secretion of the dermatophyte M. canis was found to dose-dependently evoke itch in mice. The fungal peptide micasin secreted from M. canis was then identified to elicit mouse significant scratching and itching responses. The peptide micasin was further revealed to directly activate mouse dorsal root ganglia (DRG) neurons to mediate the non-histaminergic itch. Knockout and antagonistic experiments demonstrated that MRGPRX1/C11/A1 rather than MRGPRX2/b2 activated by micasin contributed to pruritus. The chimera and mutation of MRGPRX1 showed that three domains (ECL3, TMH3 and TMH6) and four hydrophobic residues (Y99, F237, L240 and W241) of MRGPRX1 played the key role in micasin-triggered MRGPRX1 activation. Our study sheds light on the dermatophytosis-associated pruritus and may provide potential therapeutic targets and strategies against pruritus caused by dermatophytes.

Fine-tuning activation specificity of G-protein-coupled receptors via automated path searching.

Physics-based simulation methods can grant atomistic insights into the molecular origin of the function of biomolecules. However, the potential of such approaches has been hindered by their low efficiency, including in the design of selective agonists where simulations of myriad protein-ligand combinations are necessary. Here, we describe an automated input-free path searching protocol that offers (within 14 d using Graphics Processing Unit servers) a minimum free energy path (MFEP) defined in high-dimension configurational space for activating sphingosine-1-phosphate receptors (S1PRs) by arbitrary ligands. The free energy distributions along the MFEP for four distinct ligands and three S1PRs reached a remarkable agreement with Bioluminescence Resonance Energy Transfer (BRET) measurements of G-protein dissociation. In particular, the revealed transition state structures pointed out toward two S1PR3 residues F263/I284, that dictate the preference of existing agonists CBP307 and BAF312 on S1PR1/5. Swapping these residues between S1PR1 and S1PR3 reversed their response to the two agonists in BRET assays. These results inspired us to design improved agonists with both strong polar head and bulky hydrophobic tail for higher selectivity on S1PR1. Through merely three in silico iterations, our tool predicted a unique compound scaffold. BRET assays confirmed that both chiral forms activate S1PR1 at nanomolar concentration, 1 to 2 orders of magnitude less than those for S1PR3/5. Collectively, these results signify the promise of our approach in fine agonist design for G-protein-coupled receptors.

Mechanism of agonist-induced activation of the human itch receptor MRGPRX1.

Mas-related G-protein-coupled receptors X1-X4 (MRGPRX1-X4) are 4 primate-specific receptors that are recently reported to be responsible for many biological processes, including itch sensation, pain transmission, and inflammatory reactions. MRGPRX1 is the first identified human MRGPR, and its expression is restricted to primary sensory neurons. Due to its dual roles in itch and pain signaling pathways, MRGPRX1 has been regarded as a promising target for itch remission and pain inhibition. Here, we reported a cryo-electron microscopy (cryo-EM) structure of Gq-coupled MRGPRX1 in complex with a synthetic agonist compound 16 in an active conformation at an overall resolution of 3.0 Å via a NanoBiT tethering strategy. Compound 16 is a new pain-relieving compound with high potency and selectivity to MRGPRX1 over other MRGPRXs and opioid receptor. MRGPRX1 was revealed to share common structural features of the Gq-mediated receptor activation mechanism of MRGPRX family members, but the variable residues in orthosteric pocket of MRGPRX1 exhibit the unique agonist recognition pattern, potentially facilitating to design MRGPRX1-specific modulators. Together with receptor activation and itch behavior evaluation assays, our study provides a structural snapshot to modify therapeutic molecules for itch relieving and analgesia targeting MRGPRX1.

Advances in the Mechanistic Study of the Control of Oxidative Stress Injury by Modulating HDAC6 Activity.

Oxidative stress is defined as an injury resulting from a disturbance in the dynamic equilibrium of the redox environment due to the overproduction of active/radical oxygen exceeding the antioxidative ability of the body. This is a key step in the development of various diseases. Oxidative stress is modulated by different factors and events, including the modification of histones, which are the cores of nucleosomes. Histone modification includes acetylation and deacetylation of certain amino acid residues; this process is catalyzed by different enzymes. Histone deacetylase 6 (HDAC6) is a unique deacetylating protease that also catalyzes the deacetylation of different nonhistone substrates to regulate various physiologic processes. The intimate relationship between HDAC6 and oxidative stress has been demonstrated by different studies. The present paper aims to summarize the data obtained from a mechanistic study of HDAC6 and oxidative stress to guide further investigations on mechanistic characterization and drug development.

Rapid separation and identification of 96 main constituents in Huanglian Jiedu decoction via ultra-high performance liquid chromatography-Orbitrap Fusion Tribrid mass spectrometer.

Huanglian Jiedu decoction is a widely used traditional Chinese medicine with a broad spectrum of therapeutic effects, including heat clearing, detoxification, and attenuation of inflammation. However, the composition of Huanglian Jiedu decoction is still unclear due to its complexity and limitations of analytical methods. In this study, we established a fast and reliable analytical method based on ultra-performance LC-Orbitrap Fusion Tribrid mass spectrometer for high-speed separation and structural identification of multiple compounds in Huanglian Jiedu decoction. The analysis was carried out using a Hypersil GOLD C18 column (2.1 × 100 mm, 1.9 µm) with gradient elution coupled to a high-definition mass spectrometer system operating in both positive and negative ESI modes. According to the chromatographic retention time, precise molecular weight, fragment ion peaks, and published data, the main chromatographic peaks were attributed to specific molecules whose chemical structures were determined. In total, 96 components were identified, including 34 flavonoids and their glycosides, 23 alkaloids, 18 organic acids, 13 terpenoids, and 8 miscellaneous compounds. This study revealed the detailed chemical composition of Huanglian Jiedu decoction, which is of great importance for quality control and further pharmacological and mechanistic studies.

Structural insights into sphingosine-1-phosphate receptor activation.

As a critical sphingolipid metabolite, sphingosine-1-phosphate (S1P) plays an essential role in immune and vascular systems. There are five S1P receptors, designated as S1PR1 to S1PR5, encoded in the human genome, and their activities are governed by endogenous S1P, lipid-like S1P mimics, or nonlipid-like therapeutic molecules. Among S1PRs, S1PR1 stands out due to its nonredundant functions, such as the egress of T and B cells from the thymus and secondary lymphoid tissues, making it a potential therapeutic target. However, the structural basis of S1PR1 activation and regulation by various agonists remains unclear. Here, we report four atomic resolution cryo-electron microscopy (cryo-EM) structures of Gi-coupled human S1PR1 complexes: bound to endogenous agonist d18:1 S1P, benchmark lipid-like S1P mimic phosphorylated Fingolimod [(S)-FTY720-P], or nonlipid-like therapeutic molecule CBP-307 in two binding modes. Our results revealed the similarities and differences of activation of S1PR1 through distinct ligands binding to the amphiphilic orthosteric pocket. We also proposed a two-step "shallow to deep" transition process of CBP-307 for S1PR1 activation. Both binding modes of CBP-307 could activate S1PR1, but from shallow to deep transition may trigger the rotation of the N-terminal helix of Gαi and further stabilize the complex by increasing the Gαi interaction with the cell membrane. We combine with extensive biochemical analysis and molecular dynamic simulations to suggest key steps of S1P binding and receptor activation. The above results decipher the common feature of the S1PR1 agonist recognition and activation mechanism and will firmly promote the development of therapeutics targeting S1PRs.

Time to Stop Routinely Prescribing Opiates after Carpal Tunnel Release.

BACKGROUND: North American surgeons continue to routinely order narcotic medication for postoperative pain relief after carpal tunnel surgery. For some patients, this instigates persistent use. This double-blind, multicenter trial investigated whether over-the-counter medications were inferior to opioid pain control after carpal tunnel release. METHODS: Patients undergoing carpal tunnel release in five centers in Canada and the United States (n = 347) were randomly assigned to postoperative pain control with (opioid) hydrocodone/acetaminophen 5/325 mg versus over-the-counter ibuprofen/acetaminophen 600/325 mg. The two primary outcome measures were the Numeric Pain Rating Scale (0 to 10) and the six-item Patient-Reported Outcome Measurement Information System Pain Interference T-score. Secondary outcome measures were total medication used and overall satisfaction with pain medication management. RESULTS: The authors found no significant differences between opioid and over-the-counter patients in the Numeric Pain Rating Scale scores, Pain Interference T-scores, number of doses of medication, or patient satisfaction. The highest Numeric Pain Rating Scale group difference was the night of surgery, when opiate patients had 0.9/10 more pain than over-the-counter patients. The highest group difference in Pain Interference T-scores (2.1) was on the day of surgery, when the opiate patients had more pain interference than the over-the-counter group. Patient nationality or sex did not generate significant pain score differences. CONCLUSIONS: Pain management is not inferior for patients managed with over-the-counter acetaminophen/ibuprofen versus opioids. This study provides high-quality evidence that U.S. and Canadian surgeons should stop the routine prescription of narcotics after carpal tunnel surgery for patients who are not taking pain medicines daily before surgery. CLINICAL QUESTION/LEVEL OF EVIDENCE: Therapeutic, II.

Cell membrane-coated biomimetic magnetic nanoparticles for the bio-specific extraction of components from Gualou Guizhi decoction exhibiting activities against oxygen-glucose deprivation/reperfusion injury.

Gua-Lou-Gui-Zhi decoction (GLGZD) is a classical multiherb traditional Chinese medicine formula that has ameliorative effects on oxygen-glucose deprivation/reperfusion (OGD/R) injury and has been applied for the treatment of stroke in clinical practice; however, its active ingredients remain unknown. The aim of this study was to develop an effective method for screening for components of GLGZD with potential therapeutic activity against OGD/R injury. Brain microvascular endothelial cell membrane-coated magnetic beads (CMs@rBMECs-MBs) were incubated with the GLGZD extract; the bound material was eluted and the constituents were identified using solid phase extraction and ultra-performance liquid chromatography-Orbitrap Fusion Tribrid mass spectrometry (UPLC-Orbitrap Fusion Tribrid MS). The biological activities of the identified GLGZD components were analyzed using OGD/R-exposed brain endothelial cells. Seven compounds bound to the CMs@rBMECs-MBs were identified as gallic acid, paeoniflorin, liquiritigenin, isoliquiritigenin, liquiritin, isoliquiritin, and formononetin. Among them, six (except formononetin) protected brain endothelial cells against OGD/R injury in a concentration-dependent manner (20-120 µM; P < 0.01-0.05) and downregulated the expression of hypoxia-inducible factor-1α (P < 0.01) involved in the pathogenic mechanisms triggered by stroke. Our findings suggest that the screening of bioactive compounds using cell membrane-coated magnetic beads combined with solid phase extraction and UPLC-Orbitrap Fusion Tribrid MS is an effective method for the bio-specific extraction and identification of ingredients responsible for the therapeutic activity of traditional Chinese medicines.

Corrigendum: He XL, Horak E, Wang D, Li TH, Peng WH, Gan BC (2019) Descriptions of five new species in Entoloma subgenus Claudopus from China, with molecular phylogeny of Entoloma s.l. MycoKeys 61: 1-26. https://doi.org/10.3897/mycokeys.61.46446.

[This corrects the article DOI: 10.3897/mycokeys.61.46446.].

Descriptions of five new species in Entoloma subgenus Claudopus from China, with molecular phylogeny of Entoloma s.l.

Entoloma subgenus Claudopus is widely distributed, yet the taxonomy and systematics of its species are still poorly documented. In the present study, more than forty collections of Claudopus were gathered in China and subsequently analysed, based on morphological and molecular data. The results revealed first a high level of species diversity of Claudopus in China and second, there is a wide ecological range regarding the substrates and the habitats ranging from temperate, tropical to subalpine locations. Based on morphological and molecular evidence, five novel species from China are proposed, viz. E. conchatum, E. flabellatum, E. gregarium, E. pleurotoides and E. reductum. Molecular phylogeny of Entoloma s.l. was also reconstructed, based on 187 representatives of Entoloma s.l. by employing the combined ITS, LSU, mtSSU and RPB2 sequences. Ten monophyletic clades (Claudopus, Leptonia, Nolanea, Cuboid-spored Inocephalus, "Alboleptonia", Cyanula, Pouzarella, Rhodopolia, Prunuloides and Rusticoides) were recovered, while 13 taxa could not be placed in any defined clades. The results confirmed that Claudopus in a traditional morphological sense is not monophyletic and the Rusticoides-group, previously considered within Claudopus, formed a separate clade; but section Claudopus and relatives of E. undatum belong to a distinctive monophyletic group. Despite some monophyletic groups in Entoloma s.l. being distinctive in both morphology and molecular phylogeny, they were still treated as subgenera of Entoloma s.l. temporarily, because accepting them as genera will make Entoloma s.l. paraphyletic.

Dual-target anti-Alzheimer's disease agents with both iron ion chelating and monoamine oxidase-B inhibitory activity.

MAO-B leads to an increase in the levels of hydrogen peroxide and oxidative free radicals, which contribute to the aetiology of the AD. Thus, both iron ion chelators and MAO-B inhibitors can be used to treat AD. Taking the coumarin derivatives and hydroxypyridinones as the lead compounds, a series of dual-target hybrids were designed and synthesised by Click Chemistry. The compounds were biologically evaluated for their iron ion chelating and MAO-B inhibitory activity. Most of the compounds displayed excellent iron ion chelating activity and moderate to good anti-MAO-B activity. Compounds 27b and 27j exhibited the most potent MAO-B inhibitory activity, with IC50 values of 0.68 and 0.86 µM, respectively. In summary, these dual-target compounds have the potential anti-AD activity.

Validation of reference genes for quantitative gene expression analysis in Auricularia cornea.

Auricularia cornea Ehrenb., previously named A. polytricha (Mont.) Sacc, has become one of the most widely cultivated mushrooms in China. Considerable research has been conducted on its cultivation, pathogen identification, proteomics, and more. However, to the best of our knowledge, no studies have been performed on reference-gene validation in this species. Formerly, reference genes were selected for their expression levels only relied upon from others species, owing to the fact that the gene stability in this species is unknown. In this study, nine candidate genes, including tubulin alpha-1A chain (TUBA1A), ß-tubulin (Btu), phosphoglucomutase (Pgm), actin 1 (Act1), protein phosphatase 2A regulatory subunit (PP2A), polyubiquitin (UBQ), glyceraldehyde-3-phosphate dehydrogenase (Gapdh), 18S ribosomal protein (18S) and 28S ribosomal protein (28S), were evaluated among different strains and developmental stages. Four algorithms (i.e., geNorm, NormFinder, BestKeeper and RefFinder) were used to analyze candidate genes. The results revealed that UBQ was the most stable reference gene, while 18S was the least stable. Despite these results, the candidate genes were largely inadequate and only two were considered suitable. Based on candidate gene stability, PP2A and UBQ were identified as a set of usable interior control genes for future analyses in this species. This is the first systematic study conducted for selecting reference genes in A. cornea, and lays the foundation for identifying genes and quantifying gene expression in this species.

Structure and function of eTudor domain containing TDRD proteins.

Tudor domain-containing (TDRD) proteins, as a family of evolutionarily conserved proteins, have been studied extensively in recent years in terms of their biological and biochemical functions. A major function of the TDRD proteins is to recognize the N-terminal arginine-rich motifs of the P-element-induced wimpy testis (PIWI) proteins via their conserved extended Tudor (eTudor or eTud) domains, which is essential in piRNA biogenesis and germ cell development. In this review, we summarize recent progress in the study of the TDRD proteins, and discuss the molecular mechanisms for the different binding selectivity of these eTudor domains to PIWI proteins based on the available binding and structural data. Understanding the binding differences of these TDRDs to PIWI proteins will help us better understand their functional differences and aid us in developing the target-specific therapeutics, because overexpression or mutations of the human TDRD proteins have been demonstrated to associate with various diseases.

Structural analyses reveal that MBD3 is a methylated CG binder.

The MBD3, a methyl-CpG-binding domain (MBD)-containing protein, is a core subunit of the Mi-2/NuRD complex. Recent reports show that MBD3 recognizes both methylated CG (mCG)- and hydroxymethylated CG (hmCG)-containing DNA, with a preference for hmCG. However, whether the MBD3-MBD indeed has methyl-CG-binding ability is controversial. In this study, we provided the structural basis to support the ability of MBD3-MBD to bind mCG-containing DNA. We found that the MBD3-MBD bound to mCG-containing DNA through two conserved arginine fingers, and preferentially bound to mCG over hmCG, similar to other methyl-CpG-binding MBD proteins. Compared to its closest homolog MBD2, the tyrosine-to-phenylalanine substitution at Phe34 of MBD3 is responsible for a weaker mCG DNA binding ability. Based on the complex structure of MBD3-MBD with a nonpalindromic AmCGC DNA, we suggest that all the mCG-binding MBD domains can recognize mCG-containing DNA without orientation selectivity, consistent with our observations that the sequences outside the mCG dinucleotide do not affect mCG DNA binding significantly. DNA cytosine methylation is evolutionarily conserved in most metazoans, and most invertebrates have only one MBD gene, MBD2/3. We also looked into the mCG DNA binding ability of some invertebrates MBD2/3 and found that the conserved arginine fingers and a conserved structural fold are required for methylated DNA binding by MBD2/3-MBDs in invertebrates. Hence, our results demonstrate that mCG-binding arginine fingers embedded into a conserved structural fold are essential structural features for MBD2/3s binding to methylated DNA among metazoans.

Three new species of EntolomasubgenusPouzarella from China based on morphological and molecular data.

In the present paper, three additional species of EntolomasubgenusPouzarella viz. E.erectoides, E.griseocarpum and E.rubropilosum are described from China. E.rubropilosum is a typical species in section Pouzarella; E.griseocarpum and E.erectoides are members of sect. Dysthales. The taxa are further confirmed by ITS, RPB2, LSU and mtSSU analyses and phylogenetic relationships with other Entolomasubgen.Pouzarella species are also discussed. ITS sequence analysis showed that the sizes of the entire ITS region and ITS1 are remarkably divergent, while the ITS2 is conserved in length within Entolomasubgen.Pouzarella. Molecular analyses, based on the combined dataset, demonstrated that species diversity of subgen.Pouzarella in China is much higher than previously thought, in the present study twenty phylogenetic species from China are taken into consideration. On the other hand, morphological and molecular analyses suggested that classification of Entolomasubgen.Pouzarella probably has to be fundamentally re-adjusted based on additional data.

The pyramids of Gizeh, reductionist research-based progress, unintended consequences and the complexity of medicine.

Bing graduated from the Medical Faculty at Erasmus University in Rotterdam, The Netherlands in 1988. He then completed a PhD in Medical Sciences (University of Calgary), internship (University of Regina) and surgical residency (University of Western Ontario) and post-residency clinical fellowships (University of Toronto and Harvard University) followed by a research post-doctoral fellowship (Department of Cell Biology, University of Toronto). Bing has been with the Roth | McFarlane Hand and Upper Limb Centre at St. Joseph's Health Centre since 1998. He is a Professor of Surgery and Medical Biophysics at Western University. His clinical practice focuses on hand and wrist surgery, microsurgical reconstruction and complex wound reconstruction, with a particular clinical and research interest in patients with Dupuytren's contracture. He is also interested in other fibrosing conditions, such as hypertrophic scarring. Bing was a Canadian Society for Clinical Investigation (CSCI) Member of Council 2004-2011and CSCI President 2009-2011.

Intra- and inter-isolate variation of ribosomal and protein-coding genes in Pleurotus: implications for molecular identification and phylogeny on fungal groups.

BACKGROUND: The internal transcribed spacer (ITS), RNA polymerase II second largest subunit (RPB2), and elongation factor 1-alpha (EF1α) are often used in fungal taxonomy and phylogenetic analysis. As we know, an ideal molecular marker used in molecular identification and phylogenetic studies is homogeneous within species, and interspecific variation exceeds intraspecific variation. However, during our process of performing ITS, RPB2, and EF1α sequencing on the Pleurotus spp., we found that intra-isolate sequence polymorphism might be present in these genes because direct sequencing of PCR products failed in some isolates. Therefore, we detected intra- and inter-isolate variation of the three genes in Pleurotus by polymerase chain reaction amplification and cloning in this study. RESULTS: Results showed that intra-isolate variation of ITS was not uncommon but the polymorphic level in each isolate was relatively low in Pleurotus; intra-isolate variations of EF1α and RPB2 sequences were present in an unexpectedly high amount. The polymorphism level differed significantly between ITS, RPB2, and EF1α in the same individual, and the intra-isolate heterogeneity level of each gene varied between isolates within the same species. Intra-isolate and intraspecific variation of ITS in the tested isolates was less than interspecific variation, and intra-isolate and intraspecific variation of RPB2 was probably equal with interspecific divergence. Meanwhile, intra-isolate and intraspecific variation of EF1α could exceed interspecific divergence. These findings suggested that RPB2 and EF1α are not desirable barcoding candidates for Pleurotus. We also discussed the reason why rDNA and protein-coding genes showed variants within a single isolate in Pleurotus, but must be addressed in further research. CONCLUSIONS: Our study demonstrated that intra-isolate variation of ribosomal and protein-coding genes are likely widespread in fungi. This has implications for studies on fungal evolution, taxonomy, phylogenetics, and population genetics. More extensive sampling of these genes and other candidates will be required to ensure reliability as phylogenetic markers and DNA barcodes.

White mold on cultivated morels caused by Paecilomyces penicillatus.

Morchella (morel) includes prized edible and medical mushrooms in the world. Since 2012, commercial cultivation of morels in the field has developed rapidly in China. However, coupled with the rapid expansion of morel cultivation, diseases have been become serious threats to morel production. White mold is one of the most serious diseases on cultivated morels. This study aimed to confirm this pathogen by following Koch's postulates, and to identify it using molecular evidence. Our results indicated that healthy Morchella fruiting bodies inoculated with Paecilomyces sp. isolates produced typical white mold symptoms, and the internal transcribed spacer sequences of the Paecilomyces sp. were 99% similar to that recovered from an epitype of Paecilomyces penicillatus. Therefore, P. penicillatus was considered to be the causative agent of white mold. White mold occurred from the initial harvest to the storage and preservation process, and it produced white mold-like symptoms on the caps and stripes of Morchella. This is the first time that white mold has been reported on cultivated Morchella.

Dupuytren's disease susceptibility gene, EPDR1, is involved in myofibroblast contractility.

BACKGROUND: Dupuytren's Disease is a common disorder of the connective tissue characterized by progressive and irreversible fibroblastic proliferation affecting the palmar fascia. Progressive flexion deformity appears over several months or years and although usually painless, it can result in a serious handicap causing loss of manual dexterity. There is no cure for the disease and the etiology is largely unknown. A genome-wide association study of Dupuytren's Disease identified nine susceptibility loci with the strongest genetic signal located in an intron of EPDR1, the gene encoding the Ependymin Related 1 protein. OBJECTIVE: Here, we investigate the role of EPDR1 in Dupuytren's Disease. METHODS: We research the role of EPDR1 by assessing gene expression in patient tissue and by gene silencing in fibroblast-populated collagen lattice (FPCL) assay, which is used as an in vitro model of Dupuytren's contractures. RESULTS: The three alternative transcripts produced by the EPDR1 gene are all detected in affected Dupuytren's tissue and control unaffected palmar fascia tissue. Dupuytren's tissue also contracts more in the FPCL paradigm. Dicer-substrate RNA-mediated knockdown of EPDR1 results in moderate late stage attenuation of contraction rate in FPCL, implying a role in matrix contraction. CONCLUSION: Our results suggest functional involvement of EPDR1 in the etiology of Dupuytren's Disease.

Phylogenetic relationship of two popular edible Pleurotus in China, Bailinggu (P. eryngii var. tuoliensis) and Xingbaogu (P. eryngii), determined by ITS, RPB2 and EF1α sequences.

The aims of this study are to assess the utility of the internal transcribed spacer (ITS) region, and partial translation elongation factor (EF1α) and RNA polymerase II (RPB2) genes, for differentiation of Bailinggu, P. eryngii, and P. nebrodensis; to reconstruct phylogenetic relationships between the three species; and to confirm the taxonomic status of Bailinggu based on ribosomal and protein-coding genes. Pairwise genetic distances between Bailinggu, P. eryngii, and related Pleurotus strains were calculated by using the p-distance model, and molecular phylogeny of these isolates was estimated based on ITS, RPB2, and EF1α using maximum parsimony and Bayesian methods. Differences in ITS, RPB2, and EF1α sequences show that Bailinggu, P. eryngii, and P. nebrodensis are distinct at the species level. Phylogenetic analyses reveal that P. eryngii is closer to P. nebrodensis than to Bailinggu. Sequence analyses of ribosomal and protein-coding genes confirm that P. eryngii var. tuoliensis is identical to Bailinggu. P. eryngii var. tuoliensis should be raised to species level or a new name should be introduced for Bailinggu after a thorough investigation into Pleurotus isolates from Ferula in Xinjiang Province. This study helps to resolve uncertainty regarding Bailinggu, P. eryngii and P. nebrodensis, improving the resource management of these strains. ITS, EF1α, and RPB2 sequences can be used to distinguish Bailinggu, P. eryngii and P. nebrodensis as three different species, and P. eryngii var. tuoliensis should be the scientific name for Bailinggu at present.