Search Results (1,929)

Background and Objectives: Changes in the environment and physiology may be associated with an increased or decreased risk of cancer. Our study aims to evaluate the strength and the direction of the selection acting on oncosuppressor genes in association with phenotypic changes. Methods: We calculated the relative evolutionary rate (RER) using the converge method and linear regression on branches of phylogenetic trees. The association between changes in the evolutionary rate of oncosuppressors (DNA repair and cell cycle control genes) and trait selection was studied. The evolutionary rates of single oncosuppressor genes and pathways were evaluated. We studied two types of traits: those that are characteristic of vertebrates, such as homeothermy (the ability to maintain a constant body temperature), flight, and amnions; and those that are characteristic of mammals, such as high body mass and lifespan, an underground lifestyle, and hibernation. The analysis included 19,445 genes; 100 vertebrates and 46 mammalian species. We studied ancestral branches individually and all the clades having a trait. Results: Oncosuppressor genes accelerated in association with the ability to fly; p-value = 0.03 (positive or relaxed negative selection) and decelerated in homeothermic species; p-value = 0.04 (stabilizing selection). DNA repair genes were significantly accelerated in ancestral branches and in all clades of amniotic, homeothermic, and high-body-mass mammals (p-value < 0.05, FDR correction). Cell cycle control genes were under stabilizing selection in homeothermic animals, high-body-mass, long-lived, and underground mammals (p-value < 0.05, FDR correction). Data on the evolution of oncosuppressors are crucial for understanding the origin of cancer and will be important for future studies of tumor pathogenesis, pathomorphosis, and microevolution. Conclusions: The selection of traits associated with changes in cancer risk leads to positive/relaxed negative and stabilizing selection of oncosuppressor genes. Full article

Agrocybe chaxingu is a commercially important edible mushroom in China, valued for its rich bioactive compounds and distinctive umami flavor. In recent years, frequent disease outbreaks have severely limited production, as many pathogens spread rapidly and are difficult to control, posing a significant threat to the sustainable development of the industry. In this study, a systematic disease survey across major A. chaxingu cultivation areas in Jiangxi Province led to the isolation and identification of 17 potential fungal pathogens and 2 potential myxomycete pathogens using combined morphological characterization and multilocus phylogenetic analyses including the internal transcribed spacer (ITS) region, 28S large subunit ribosomal RNA (LSU), translation elongation factor (tef1), RNA polymerase largest subunit (rpb1), RNA polymerase second largest subunit (rpb2), Histone (H3), Beta tubulin (tub2), and 18S ribosomal RNA (18S rRNA). Among the identified diseases, white slime disease showed the highest incidence (17.3%) and was attributed to the slime mold Fuligo gyrosa, with pathogenicity confirmed according to Koch’s postulates. F. gyrosa proved highly virulent to both fruiting bodies and mycelia, enveloping host mycelium via plasmodial expansion, inhibiting growth, inducing structural rupture, and causing progressive degradation. Infection was accompanied by the deposition of characteristic stress-related pigments in the mycelium. This study provides the first detailed characterization of F. gyrosa infection dynamics in A. chaxingu mycelium. These findings provide new insights into the myxomycete pathogenesis in edible fungi and provide a foundation for the accurate diagnosis, targeted prevention, and sustainable management of diseases in A. chaxingu cultivation. Full article

The cereal cyst nematode, Heterodera avena, is responsible for substantial economic losses in the global production of wheat, barley, and other cereal crops. Extracellular enzymes, particularly those from the glycoside hydrolase 18 (GH18) family, such as chitinases secreted by Trichoderma spp., play a crucial role in nematode control. However, the genome-wide analysis of Trichoderma longibrachiatum T6 (T6) GH18 family genes in controlling of H. avenae remains unexplored. Through phylogenetic analysis and bioinformatics tools, we identified and conducted a detailed analysis of 18 GH18 genes distributed across 13 chromosomes. The analysis encompassed gene structure, evolutionary development, protein characteristics, and gene expression profiles following T6 parasitism on H. avenae, as determined by RT-qPCR. Our results indicate that 18 GH18 members in T6 were clustered into three major groups (A, B, and C), which comprise seven subgroups. Each subgroup exhibits highly conserved catalytic domains, motifs, and gene structures, while the cis-acting elements demonstrate extensive responsiveness to hormones, stress-related signals, and light. These members are significantly enriched in the chitin catabolic process, extracellular region, and chitinase activity (GO functional enrichment), and they are involved in amino sugar and nucleotide sugar metabolism (KEGG pathway enrichment). Additionally, 13 members formed an interaction network, enhancing chitin degradation efficiency through synergistic effects. Interestingly, 18 members of the GH18 family genes were expressed after T6 parasitism on H. avenae cysts. Notably, GH18-3 (Group B) and GH18-16 (Group A) were significantly upregulated, with average increases of 3.21-fold and 3.10-fold, respectively, from 12 to 96 h after parasitism while compared to the control group. Meanwhile, we found that the GH18-3 and GH18-16 proteins exhibit the highest homology with key enzymes responsible for antifungal activity in T. harzianum, demonstrating dual biocontrol potential in both antifungal activity and nematode control. Overall, these results indicate that the GH18 family has undergone functional diversification during evolution, with each member assuming specific biological roles in T6 effect on nematodes. This study provides a theoretical foundation for identifying novel nematicidal genes from T6 and cultivating highly efficient biocontrol strains through transgenic engineering, which holds significant practical implications for advancing the biocontrol of plant-parasitic nematodes (PPNs). Full article

Porcine Sapelovirus (PSV) is widely prevalent in pig herds throughout the world and induces diarrhea, encephalomyelitis, respiratory tract symptoms, and reproductive disorders. However, the epidemiological and genetic evolution characteristics of PSV remain unclear in Yunnan Province. In this study, 1622 fecal samples were collected from pig farms in Yunnan Province. PSV and its co-infection rates with other pathogens were detected; then, the PSV VP1 gene was amplified and sequenced; and the genetic evolution characteristics of the VP1 gene were analyzed. The overall infection rate of PSV in Yunnan Province was 36.50%, and the differences among regions were significant (p < 0.05). The positive rates among different seasons were significantly different (p < 0.01), ranging from 73.33% (autumn) to 19.00% (summer). The PSV positive rate in diarrhea samples (47.26%) was significantly higher (p < 0.001) than that of non-diarrhea samples (31.77%). The co-infection rates of PSV with porcine rotavirus (PoRV) and PSV with porcine epidemic diarrhea virus (PEDV) were 5.07% and 3.04%. A total of 36 VP1 sequences were obtained, and the average identity among the 36 sequences was 85.3%, which was higher than that with other reference strains. Phylogenetic analysis revealed that all 36 PSV strains belonged to the PSV-1 genotype. The VP1 gene was under strong negative selection pressure (average dN/dS = 0.0838); however, the 95th amino acid was under positive selection pressure. Our study revealed the epidemiological, co-infection, and genetic evolution characteristics of PSV in pig herds of Yunnan Province, providing more data for preventing and controlling diarrhea pathogens in pigs. Full article

Rhizopogon, a globally distributed genus of edible ectomycorrhizal fungi, is the focus of this study. This study describes a new species, Rhizopogon qujingensis sp. nov., along with two newly recorded species of the genus Rhizopogon from China. The new species is distinguished from other known Rhizopogon species by its distinctly phylogenetic position and unique morphological characteristics, the species is characterized by comparatively smaller basidiomata, a peridium that exhibits yellow tinting after injury and contains red-brown pigment, along with smaller, narrowly oblong to elongate spores. Furthermore, R. rubescens and R. evadens are recorded for the first time in China, with their taxonomic status confirmed through integrated morphological and molecular analysis, thereby extending their known geographical distribution. Phylogenetic analysis was conducted to elucidate the relationships between Chinese Rhizopogon species and other taxa within the genus. This research contributes essential data for advancing the understanding of global Rhizopogon species diversity and biogeographic patterns. Full article

β-D-xylosidases (BXLs) are pivotal enzymes in xylan degradation, playing essential roles in plant development and stress responses. In this study, we identified 29 GmBXL genes in soybean through homolog alignment. Phylogenetic analysis classified these genes into three groups, with Group III being legume-specific. The GmBXLs are unevenly distributed across 15 chromosomes, with their expansion driven by both tandem and segmental duplications. Conserved motif and domain analyses revealed functional conservation, particularly in family 3 of glycoside hydrolase domains. Promoter regions of GmBXLs are enriched with hormone-responsive and stress-related cis-elements, indicating their involvement in diverse biological processes. Tissue-specific expression analysis revealed differential GmBXLs expression across leaves, roots, flowers, and seeds, with GmBXL13 and GmBXL26 exhibiting notably high transcript levels in pods and seeds. Under salt stress, 26 GmBXLs exhibited significant expression changes, with 20 genes up-regulated in both leaves and roots, highlighting their roles in salt tolerance. These findings enhance our understanding of the evolutionary and functional characteristics of GmBXLs, providing valuable insights for molecular breeding of salt-tolerant soybean varieties. Full article

The LHCB gene family plays a crucial role in light harvesting and photoprotection in plants by encoding key components of the photosystem II antenna complex. The LHCB genes are also involved in salt stress. In this study, we systematically identified and characterized 16 LbaLHCB genes in the economically important medicinal plant Lycium barbarum. Comprehensive bioinformatics analyses revealed that these genes are unevenly distributed across seven chromosomes, with notable gene clustering on chromosome 11. Phylogenetic analysis classified them into seven distinct subfamilies, with the LbaLHCB1 subfamily showing significant expansion through gene duplication events. qRT-PCR and transcriptome analyses revealed tissue-specific expression patterns, with LbaLHCB1.6 exhibiting preferential expression in developing fruits, suggesting its potential involvement in fruit development and quality formation. Under salt stress conditions, the LbaLHCB genes displayed dynamic temporal responses: LbaLHCB1.5 was rapidly induced during early stress (1–3 h), LbaLHCB7 reached peak expression at mid-phase (6–12 h), while LbaLHCB1.2 showed significant downregulation during late stress response (24 h). Promoter analysis identified multiple stress-responsive cis-elements, providing molecular insights into their regulation under abiotic stress. These findings significantly advance our understanding of the LbaLHCB gene family’s structural characteristics and functional diversification in L. barbarum, particularly in relation to photosynthesis regulation and stress adaptation. The study provides valuable genetic resources for future molecular breeding aimed at improving stress tolerance and fruit quality in this important medicinal crop. Full article

Background: Pseudorabies virus (PRV), a critical porcine herpesvirus, induces severe diseases in both livestock and wildlife, imposing an incalculable burden and economic losses in livestock production. In this study, we investigated the evolutionary mechanisms and host adaptation strategies of the PRV gB gene through genomic alignment. The gB gene is highly conserved in PRV, and its encoded gB protein exhibits functional interchangeability across different herpesvirus species. Notably, the gB protein elicits the production of both complement-dependent and complement-independent neutralizing antibodies in animals, while also being closely associated with syncytium formation. Methods: Phylogenetic analysis and codon usage pattern analysis were performed in this study. A total of 110 gB gene sequences were analyzed, which were collected from [2011 to 2024] across the following regions: [Fujian, Shanxi, Guangxi, Guangdong, Chongqing, Henan, Shaanxi, Heilongjiang, Sichuan, Jiangsu, Jilin, Huzhou, Shandong, Hubei, Jiangxi, Beijing, Shanghai, Chengdu (China)], [Budapest, Szeged (Hungary)], [Tokyo (Japan)], [London (United Kingdom)], [Athens (Greece)], [Berlin (Germany)], and [New Jersey (United States)]. Results: The gB gene of PRV employs an evolutionary “selective optimization” strategy to maintain a dynamic balance between ensuring functional expression and evading host immune pressure, with this core trend strongly supported by its codon usage bias and mutation characteristics. First, the gene exhibits significant codon usage bias [Effective Number of Codons (ENC) = 27.94 ± 0.1528], driven primarily by natural selection rather than mere mutational pressure. Second, phylogenetic analysis shows that the second codon position of gB has the highest mutation rate (1.0586)—a feature closely linked to its antigenic variation and immune escape capabilities, further reflecting adaptive evolution against host immune pressure. Additionally, ENC-GC3 plot analysis reveals the complex regulatory mechanisms underlying codon bias formation, providing molecular evidence for the “selective optimization” strategy and clarifying PRV’s core evolutionary path to balance functional needs and immune pressure over time. Conclusions: Our study findings deepen our understanding of the evolutionary mechanisms of PRV and provide theoretical support for designing vaccines and assessing the risk of cross-species transmission. Full article

The concept of a genome signature broadly refers to characteristic patterns in DNA sequences that enable the identification and comparison of species or individuals, often without requiring sequence alignment. Such signatures have applications ranging from forensic identification of individuals to cancer genomics. In comparative genomics and evolutionary biology, genome signatures typically rely on statistical properties of DNA that are species-specific and carry phylogenetic information reflecting evolutionary relationships. We propose a novel genome signature based on the compositional structure of DNA, defined by the distributions of strong/weak, purine/pyrimidine, and keto/amino ratios across DNA segments identified through entropic segmentation. We observe that these ratio distributions are similar among closely related species but differ markedly between distant ones. To quantify these differences, we employ the Jensen–Shannon distance—a symmetric and robust measure of distributional dissimilarity—to define a genome-to-genome distance metric, termed Segment Compositional Distance ($\mathcal{D}$). Our results demonstrate a clear correlation between $\mathcal{D}$ and species divergence times, and also that this metric captures a strong phylogenetic signal. Our method employs a genome-wide approach rather than tracking specific mutations; thus, $\mathcal{D}$ offers a coarse-grained perspective on genome compositional evolution, contributing to the ongoing discussion surrounding the molecular clock hypothesis. Full article

An integrative study of material from Yunnan Province, China, revealed two new Lophozia species. These species and several other representatives of the genus known from East Asia form a distinct clade within the phylogenetic structure of Lophozia. Descriptions, photographs, and comments regarding the morphological characteristics of the new taxa are provided. Lophozia neglecta is characterized by pink gemmae (another taxon with similar gemmae is East Asian L. koreana), whereas L. vinacea is characterized by vine-purple gemmae, which were previously unknown in the genus. Additionally, molecular analysis confirmed the occurrence of L. fuscovirens, a poorly known Lophozia taxon with brown gemmae, in the Kamchatka Peninsula. The taxonomic diversity of Lophozia in East Asia comprises 12 species belonging to various distribution groups, including the Sino-Himalayan and broadly East Asian groups. Full article

Glutamine synthetase plays an essential role in regulating plant growth and development. However, few studies have analyzed the roles of TaGS in wheat under abiotic stress conditions. In this study, we identified and analyzed the members of the TaGS gene family in Triticum aestivum L., focusing on their gene characteristics, phylogenetic evolution, cis-elements, transcriptional and post-translational modifications, and expression profiling in response to abiotic stress. Twelve TaGS genes were divided into four subfamilies. The synteny analysis revealed that wheat and the five other species share GS homologs. Several potential transcription factors were identified as regulators of TaGS genes. TaGS contains 19 microRNA binding sites, phosphorylation sites, and ubiquitination sites. TaGS genes exhibited tissue-specific expression across various developmental stages and were differentially expressed in response to abiotic stress. For instance, TaGS1-3-4A/4B/4D were upregulated in the leaves and roots of wheat seedlings under abiotic stress conditions. Furthermore, gene ontology annotation was performed on the TaGS-interacting proteins screened by immunoprecipitation–mass spectrometry to elucidate the regulatory network associated with TaGS. This study lays a foundation for further functional research of TaGS genes in response to abiotic stress and provides potential information for enhancing stress tolerance in wheat. Full article

Gossypol, a polyphenolic naphthalene derivative and yellow polyphenolic pigment found in cotton seed glands, presents notable environmental, animal, and human health hazards. To screen for yeast strains capable of utilizing gossypol and to investigate their removal efficiency and mechanisms. Yeast strains capable of utilizing gossypol as the exclusive carbon source were isolated from cotton field soil. The identification of these strains involved assessment of colony morphology, physiological and biochemical characteristics, and phylogenetic analysis utilizing 26S rDNA gene sequences. Safety evaluations included hemolytic and antibiotic susceptibility tests. The growth responses of the selected strains to varying temperatures and pH levels were determined. Using cotton meal as the solid fermentation substrate, the effects of single factors on gossypol removal by the strains were determined. The intracellular and extracellular localization as well as the nature of the gossypol-removing active components in the strains were characterized, followed by an investigation into the molecular mechanism of gossypol removal using LC-MS analysis. A total of 17 gossypol-utilizing strains were isolated from cotton field soil samples, with strain ZYS-3 demonstrating superior removal capability. Strain ZYS-3 was identified as Meyerozyma guilliermondii, exhibiting no hemolytic activity and susceptibility to nine commonly used antifungal agents. The optimal growth parameters for this strain were determined to be a temperature of 30 °C and a pH of 5.0. In solid-state fermentation using cotton meal at 30 °C with initial fermentation conditions (10% corn flour added as an external carbon source, 40% moisture content, and 6% inoculum concentration) for 3 days, strain ZYS-3 achieved a gossypol removal rate of 73.57%. Subsequent optimization of the fermentation process, including the addition of 10% corn flour as an external carbon source, adjustment of moisture content to 55%, and inoculum concentration to 10%, resulted in an increased gossypol removal rate of 89.77% after 3 days of fermentation, representing a 16.2% enhancement over the initial conditions. Assessment of gossypol removal activity revealed that strain ZYS-3 predominantly removes gossypol through the secretion of extracellular enzymes targeting specific active groups (phenolic hydroxyl groups and aldehyde groups) within the gossypol molecule. These enzymes facilitate oxidation and elimination reactions, leading to the opening of the naphthalene ring and subsequent removal of gossypol. Full article

Small heat shock proteins play a pivotal role in maintaining protein homeostasis under abiotic stress conditions and are indispensable for plant viability. In the present study, a comprehensive characterization of this gene family in Allium sativum was conducted through genome-wide sequence identification, phylogenetic reconstruction, conserved motif analysis, promoter cis-element profiling, transcriptomic investigation, quantitative real-time PCR, subcellular localization, and yeast-based functional assays. A total of 114 small heat shock protein genes were identified across eight chromosomes and subsequently classified into ten phylogenetic subgroups. All encoded proteins conserved the α-crystallin domain, whereas their exon–intron architectures and promoter elements responsive to environmental stress or phytohormones exhibited considerable diversity. The predicted proteins range from 130 to 364 amino acids, with isoelectric points (pI) spanning 3.97 to 9.95 and GRAVY values from −1.131 to −0.014, indicating predominantly hydrophilic characteristics. Subcellular localization analysis revealed a broad distribution across the cytoplasm, chloroplasts, mitochondria, and other compartments, with the majority (74 proteins) localized in the cytoplasm. Synteny analysis uncovered two segmentally duplicated gene pairs (AsHSP20-80/31, and AsHSP20-81/32), both showing strong purifying selection (Ka/Ks = 0.0459 and 0.2545, respectively), suggesting functional conservation. Expression profiling demonstrated predominant transcript accumulation in bulbs and floral organs, with significant induction under heat, salinity, and jasmonic acid treatments. qRT–PCR validation further confirmed that several candidate genes, notably AsHSP20-94 and AsHSP20-79, were strongly and consistently upregulated across multiple stress conditions, underscoring their roles as core stress-responsive regulators. Subcellular localization experiments demonstrated that representative proteins are targeted to the cytoplasm, nucleus and chloroplasts. Furthermore, heterologous expression of AsHSP20-79 in yeast conferred marked thermotolerance. Collectively, these findings reveal extensive expansion and functional divergence of the small heat shock protein gene family in garlic and provide valuable candidate genes for improving stress resilience in this important crop species. Full article

Mining novel Streptomyces species from extreme environments provides a valuable strategy for the discovery of new antibiotics. Here, we report a strain of Streptomyces sp. HMX87^T, which exhibits antimicrobial activity and was isolated from desert soil collected in the Tuha Basin, China. Molecular taxonomic analysis revealed that the 16S rRNA gene sequence of strain HMX87^T shares the highest similarity with those of Streptomyces bellus CGMCC 4.1376^T (98.5%) and Streptomyces coerulescens DSM 40146^T (98.43%). In phylogenetic trees, it formed a distinct branch. The average nucleotide identity (ANI) and digital DNA–DNA hybridization (dDDH) values between strain HMX87^T and the above two type strains were below the thresholds of 95% and 70%, respectively, confirming that strain HMX87^T represents a novel species within the genus Streptomyces, for which the name Streptomyces hamibioticus sp. nov. is proposed. Physiologically, the strain HMX87^T grew at temperatures ranging from 25 to 37 °C, tolerated pH values from 5 to 12, and survived in NaCl concentrations of 0% to 8% (w/v). Chemotaxonomic characterization indicated the presence of LL-diaminopimelic acid (LL-DAP) in the cell wall, ribose and galactose as whole-cell hydrolysate sugars, MK-9(H8) (66.3%) as the predominant menaquinone, and iso-C_16:0 (25.94%) and anteiso-C_15:0 (16.98%) as the major fatty acids characteristics that clearly distinguish it from its closest relatives. Whole-genome sequencing of strain HMX87^T revealed an abundance of genes associated with high-temperature tolerance, salt-alkali resistance, and antimicrobial activity. The genomic features and secondary metabolic potential reflect its adaptation to extreme environmental conditions, including high temperature, salinity, alkalinity, strong ultraviolet radiation, and oligotrophic nutrients. The strain HMX87^T has been deposited in the Czech Collection of Microorganisms (CCM 9454^T) and the Guangdong Microbial Culture Collection Center (GDMCC 4.391^T). The 16S rRNA gene and whole-genome sequences have been submitted to GenBank under accession numbers PQ182592 and PRJNA1206124, respectively. Full article

Senecavirus A (SVA) is an emerging threat to swine populations due to its potential to cause vesicular lesions, which are difficult to differentiate from other vesicular diseases of swine such as foot and mouth disease (FMD), requiring significant resources for differential diagnosis. The first Taiwanese isolate of SVA was identified in 2006, although the first clinical case was not reported until 2012. The genetic characteristics and seroprevalence of SVA in Taiwan remain unclear. This study aimed to assess the seroprevalence and genetic diversity of SVA in nursery/weaned swine and finisher swine on Taiwanese pig farms. Phylogenetic analysis of seven Taiwanese SVA isolates revealed clustering into groups I and II. The 2006 and 2012 isolates shared 95.5% and 95.7% identity, respectively, with an early USA strain (MT360258), while more recent strains collected between 2018 and 2022 exhibited 95.7–98.8% identity with a 2020 USA strain (MZ733977). Serological analysis of swine from 300 farms showed significantly higher herd-level seroprevalence in nursery/weaned swine (53%) than finisher swine (6.7%). Furthermore, comparative analysis of nine known B cell epitopes showed high sequence conservation across Taiwanese and global strains. These findings provide important baseline data on the genetic diversity and seroprevalence of SVA in Taiwan and support the development of improved surveillance strategies for this emerging swine pathogen. Full article