OBJECTIVE: This study reports the first imported case of Lassa fever (LF) in China. Laboratory detection and molecular epidemiological analysis of the Lassa virus (LASV) from this case offer valuable insights for the prevention and control of LF. METHODS: Samples of cerebrospinal fluid (CSF), blood, urine, saliva, and environmental materials were collected from the patient and their close contacts for LASV nucleotide detection. Whole-genome sequencing was performed on positive samples to analyze the genetic characteristics of the virus. RESULTS: LASV was detected in the patient's CSF, blood, and urine, while all samples from close contacts and the environment tested negative. The virus belongs to the lineage IV strain and shares the highest homology with strains from Sierra Leone. The variability in the glycoprotein complex (GPC) among different strains ranged from 3.9% to 15.1%, higher than previously reported for the seven known lineages. Amino acid mutation analysis revealed multiple mutations within the GPC immunogenic epitopes, increasing strain diversity and potentially impacting immune response. CONCLUSION The case was confirmed through nucleotide detection, with no evidence of secondary transmission or viral spread. The LASV strain identified belongs to lineage IV, with broader GPC variability than previously reported. Mutations in the immune-related sites of GPC may affect immune responses, necessitating heightened vigilance regarding the virus.
Humans ; China/epidemiology* ; Genome, Viral ; Lassa Fever/virology* ; Lassa virus/classification* ; Molecular Epidemiology ; Phylogeny

OBJECTIVE: Poxviruses are zoonotic pathogens that infect humans, mammals, vertebrates, and arthropods. However, the specific role of ticks in transmission and evolution of these viruses remains unclear. METHODS: Transcriptomic and metatranscriptomic raw data from 329 sampling pools of seven tick species across five continents were mined to assess the diversity and abundance of poxviruses. Chordopoxviral sequences were assembled and subjected to phylogenetic analysis to trace the origins of the unblasted fragments within these sequences. RESULTS: Fifty-eight poxvirus species, representing two subfamilies and 20 genera, were identified, with 212 poxviral sequences assembled. A substantial proportion of AT-rich fragments were detected in the assembled poxviral genomes. These genomic sequences contained fragments originating from rodents, archaea, and arthropods. CONCLUSION Our findings indicate that ticks play a significant role in the transmission and evolution of poxviruses. These viruses demonstrate the capacity to modulate virulence and adaptability through horizontal gene transfer, gene recombination, and gene mutations, thereby promoting co-existence and co-evolution with their hosts. This study advances understanding of the ecological dynamics of poxvirus transmission and evolution and highlights the potential role of ticks as vectors and vessels in these processes.
Animals ; Poxviridae/physiology* ; Ticks/virology* ; Phylogeny ; Transcriptome ; Evolution, Molecular ; Poxviridae Infections/virology* ; Genome, Viral

OBJECTIVE: Recombination events are common and serve as the primary driving force of diverse human adenovirus (HAdV), particularly in children with acute respiratory tract infections (ARIs). Therefore, continual monitoring of these events is essential for effective viral surveillance and control. METHODS: Respiratory specimens were collected from children with ARIs between January 2022 and December 2023. The penton base, hexon, and fiber genes were amplified from HAdV-positive specimens and sequenced to determine the virus type. In cases with inconsistent typing results, genes were cloned into the pGEM-T vector to detect recombination events. Metagenomic next-generation sequencing (mNGS) was performed to characterize the recombinant HAdV genomes. RESULTS: Among 6,771 specimens, 277 (4.09%, 277/6,771) were positvie for HAdV, of which 157 (56.68%, 157/277) were successfully typed, with HAdV-B3 being the dominant type (91.08%, 143/157), and 14 (5.05%, 14/277) exhibited inconsistent typing results, six of which belonged to species B. The penton base genes of these six specimens were classified as HAdV-B7, whereas their hexon and fiber genes were classified as HAdV-B3, resulting in a recombinant genotype designated P7H3F3, which closely resembled HAdV-B114. Additionally, a partial gene encoding L1 52/55 kD was identified, which originated from HAdV-B16. CONCLUSION A novel recombinant, P7H3F3, was identified, containing sequences derived from HAdV-B3 and HAdV-B7, which is similar to HAdV-B114, along with additional sequences from HAdV-B16.
Humans ; Adenoviruses, Human/isolation & purification* ; Respiratory Tract Infections/epidemiology* ; Child, Preschool ; Child ; Recombination, Genetic ; Male ; Beijing/epidemiology* ; Infant ; Female ; Phylogeny ; Adenovirus Infections, Human/epidemiology* ; Acute Disease ; Genome, Viral

As a biocatalyst, laccase has been widely studied and applied in the papermaking industry. However, the low catalytic efficiency and poor stability of natural laccase limit its application in the pulping process. To develop the laccase with high activity and strong tolerance, we carried out directed evolution for modification of the laccase derived from Bacillus pumilus and screened out the mutants F282L/F306L and Q275P from the random mutant library by high-throughput screening. The specific activities of F282L/F306L and Q275P were 280.87 U/mg and 453.94 U/mg, respectively, which were 1.42 times and 2.30 times that of the wild-type laccase. Q275P demonstrated significantly improved thermal stability, with the relative activity 20% higher than that of the wild-type laccase after incubation at 40 ℃, 50 ℃, and 70 ℃ for 4 h. F282L/F306L and Q275P showed greater tolerance to metal ions and organic solvents than the wild-type laccase. The K_m value of the wild-type laccase was 374.97 μmo/L, and those of F282L/F306L and Q275P were reduced to 318.96 μmo/L and 360.71 μmo/L, respectively, which suggested that the substrate affinity of laccase was improved after mutation. The k_cat values of F282L/F306L and Q275P for the substrate ABTS were 574.00 s^-1 and 898.03 s^-1, respectively, which were 1.1 times and 1.7 times that of the wild-type laccase, indicating the improved catalytic efficiency. Q275P demonstrated better performance than the wild-type laccase in pulping, as manifested by the reduction of 0.82 in the Kappa number and the increases of 2.00% ISO, 7.8%, and 7.2% in whiteness, tensile index, and breaking length, respectively. This work lays a foundation for improving the adaptation of laccase to the environment of the papermaking industry.
Laccase/chemistry* ; Directed Molecular Evolution ; Enzyme Stability ; Bacillus pumilus/genetics* ; Mutation ; Biocatalysis ; Catalysis

We studied the genetic diversity and established the DNA molecular identify for Prunus mume with both ornamental and edible values, aiming to collect, identify, evaluate, and breed new varities of this plant and promote the upgrading of the P. mume industry chain in northern China. We employed 13 pairs of primers with good polymorphism, clear bands, and good repeatability to analyze the genetic diversity and establish the molecular identify of 68 germplasm accessions of P. mume with both ornamental and edible values from Xingtai, Hebei Province. We then employed the unweighted pair-group method with arithmetic means (UPGMA) to perform the cluster analysis based on genetic distance. After that, we analyzed the genetic structure of the 68 germplasm accessions based on a Bayesian model. The 13 pairs of SSR primers amplified a total of 124 alleles from 68 P. mume germplasm accessions, with the mean number of alleles (Na) of 9.538 5, the minor allele frequency (MAF) of 0.369 3, the mean number of effective alleles (Ne) of 4.483 5, and the mean Shannon genetic diversity index (I) of 1.712 4. The mean Nei's gene diversity index (H) of 0.763 7, the mean observed heterozygosity (Ho) of 0.719 5, the mean expected heterozygosity (He) of 0.769 3, the mean polymorphism information content (PIC) of 0.733 6, and the mean genetic similarity (GS) of 0.772 9 suggested that there were significant genetic differences and rich genetic diversity among the studied P. mume germplasm accessions. The cluster analysis revealed that the 68 accessions were classified into three groups, with the mean genetic distance of 0.622 6. The population structure analysis classified the germplasm accessions into two populations. According to the PIC of primers, we selected primers for combination and constructed the combination with the fewest primers required for germplasm differentiation of P. mume with both ornamental and edible values. This study provides a theoretical basis for the innovation and industrial upgrading of P. mume with both ornamental and edible values in gardening and the improvement of breeding efficiency.
Prunus/classification* ; Microsatellite Repeats/genetics* ; Genetic Variation ; China ; Phylogeny ; Polymorphism, Genetic ; DNA, Plant/genetics* ; Alleles

Beta-amylases (BAMs), key enzymes in starch hydrolysis, play an important role in plant growth, development, and resistance to abiotic stress. To mine the saline-alkali tolerance-related BAM genes in alfalfa (Medicago sativa L.), we identified MsBAM genes in the whole genome. The physicochemical properties, phylogeny, gene structures, conserved motifs, secondary structures, promoter cis-acting elements, chromosome localization, and gene replication relationships of BAM gene family members were analyzed. RNA-seq and quantitative real-time PCR (qRT-PCR) were employed to analyze the expression patterns of BAM family members under saline-alkali stress. The results showed that 54 BAM genes were identified in the genome, which were classified into 8 subgroups according to the phylogenetic tree. The members of the same subgroup had similar gene structures except that those of subgroups 1 and 7 had large differences. Conserved motif analysis showed that all MsBAM proteins had a typical glycohydrolysis domain. The chromosome localization analysis showed that MsBAM gene family members were unevenly distributed on 27 chromosomes. The duplication of gene segments led to the increase in BAM gene number in alfalfa. The promoters of BAM genes contained a large number of elements in response to plant hormones and stress. Transcriptome data and qRT-PCR results showed that the expression levels of most MsBAM genes were up-regulated in response to saline-alkali stress. Under the saline-alkali stress, the expression levels of 28 genes, including MsBAM6, were up-regulated on days 1 and 7, and those of 5 genes, including MsBAM9, were up-regulated by over 2 folds. In addition, under salt-alkali stress, BAM activity and soluble sugar content were significantly increased. These results indicate that BAM genes play a key role in alfalfa in response to saline-alkali stress, laying a foundation for further research in this field.
Medicago sativa/physiology* ; beta-Amylase/metabolism* ; Phylogeny ; Gene Expression Regulation, Plant ; Stress, Physiological/genetics* ; Multigene Family ; Alkalies ; Plant Proteins/genetics*

In recent years, the spread of clubroot disease caused by Plasmodiophora brassicae infection has seriously affected the yield and quality of Brassica juncea (L.) Czern.. The cascade of mitogen-activated protein kinases (MAPKs), a highly conserved signaling pathway, plays an important role in plant responses to both biotic and abiotic stress conditions. To mine the MAPK genes related to clubroot disease resistance in B. juncea, we conducted a genome-wide analysis on this vegetable, and we analyzed the phylogenetic evolution and gene structure of the MAPK gene family in mustard. The 66 BjuMAPK genes identified by screening the whole genome sequence of B. juncea were unevenly distributed on 17 chromosomes. At the genomic scale, tandem repeats led to an increase in the number of MAPK genes in B. juncea. It was found that members of the same subfamily had similar gene structures, and there were great differences among different subfamilies. These predicted cis-acting elements were related to plant hormones, stress resistance, and plant growth and development. The expression of BjuMAPK02, BjuMAPK15, BjuMAPK17, and BjuMAPK19 were down-regulated or up-regulated in response to P. brassicae infection. The above results lay a theoretical foundation for further studying the functions of BjuMAPK genes in B. juncea in response to the biotic stress caused by clubroot disease.
Mustard Plant/parasitology* ; Plasmodiophorida/pathogenicity* ; Plant Diseases/genetics* ; Mitogen-Activated Protein Kinases/metabolism* ; Phylogeny ; Disease Resistance/genetics* ; Gene Expression Regulation, Plant ; Genome, Plant ; Plant Proteins/genetics*

Lateral organ boundaries (LOB) domain (LBD) genes encode a family of transcription factors ubiquitous in higher plants, playing crucial roles in the growth, development, and stress responses. Hippophae rhamnoides, known for its drought, cold, and saline-alkali tolerance, offers significant economic benefits and ecological values. Utilizing the whole genome data and bioinformatics approaches, this study identified and analyzed the LBD gene family in H. rhamnoides. Additionally, we examined the expression pattern of HrLBD genes by integrating the transcriptome data from male and female flower buds in development. Eleven LBD genes were identified in H. rhamnoides, and these genes were distributed on five chromosomes. The HrLBD proteins showed the lengths ranging from 159 aa to 302 aa, the molecular weights between 18 249.91 Da and 33 202.01 Da, and the subcellular localization in the nucleus or chloroplasts. LBD protein domains and gene structures were highly conserved, featuring similar motifs. The phylogenetic analysis of HrLBD genes and the LBD genes in Arabidopsis thaliana and Hordeum vulgare revealed that HrLBD genes falled into two major categories: Class Ⅰ and Class Ⅱ. The transcriptome data and RT-qPCR showed that HrLBD genes were highly expressed in male flower buds, with up-regulated expression levels throughout bud development, indicating a role in the specific stage of male flower bud development. This study lays a theoretical foundation for exploring the roles of HrLBD genes in the growth, development, and sex differentiation of H. rhamnoides flower buds.
Flowers/genetics* ; Hippophae/metabolism* ; Phylogeny ; Gene Expression Regulation, Plant ; Plant Proteins/genetics* ; Transcription Factors/genetics* ; Multigene Family ; Genes, Plant

Glucosidases are an indispensable class of enzymes in the sugar metabolism of organisms. To investigate the biological functions and expression patterns of α-glucosidases (AGLUs) and β-glucosidases (BGLUs), we identified the two family members in the genome of melon (Cucumis melo). The number, location on chromosomes, gene structure, subcellular localization, conserved motifs, and phylogenetic relationship of the two family members were analyzed. Based on the cis-acting elements in the promoter region and protein interaction models, their functions were preliminarily predicted. Furthermore, the gene expression of the two family members was determined by qRT-PCR. The results showed that the melon genome contained five AGLU family members on five chromosomes, and all of the five members were located in the extracellular matrix, with the amino acid sequence lengths ranging from 899 aa to 1 060 aa. The melon genome carried 18 BGLU family members on 8 chromosomes, and all the members were located in the cell membrane or cytoplasm, with the amino acid lengths ranging from 151 aa to 576 aa. The qRT-PCR results showed that the expression of about 50% of the genes was down-regulated upon cold stress. CmAGLU5 and CmBGLU7 may be key members of the two families, respectively, in response to cold stress. The expression of all members of the two families was up-regulated under abscisic acid (ABA), high salt, and drought stress. In the AGLU family, CmAGLU3 was the key gene in response to ABA and high salt stress, while CmAGLU4 was the key gene in response to drought stress. In the BGLU family, CmBGLU18 was the key gene in response to ABA, while CmBGLU6 was the key gene in response to high salt and drought stress.
beta-Glucosidase/metabolism* ; Phylogeny ; alpha-Glucosidases/metabolism* ; Gene Expression Regulation, Plant ; Cucurbitaceae/enzymology* ; Multigene Family ; Cucumis melo/enzymology* ; Stress, Physiological

Docynia delavayi (Franch.) Schneid. is an economic fruit plant with high medicinal and edible values. The TCP gene family plays a vital role in plant growth and development. To explore the function of the TCP gene family in the growth and development of D. delavayi. In this study, the TCP gene family (DdeTCP) members were identified from the D. delavayi genome and their expression levels at different stages of seed germination and fruit development were analyzed. The results showed that a total of 18 DdeTCP genes were identified from the D. delavayi genome, with uneven location on 11 chromosomes. The phylogenetic tree showed that the 18 DdeTCPs could be classified into class Ⅱ (3) and class Ⅱ (15), suggesting that functional differentiation occurred among the DdeTCP family members. DdeTCP11 highly homologous to AtTCP14 was highly expressed in the early stage of seed germination, which suggested that this gene played a key role in seed germination. In addition, DdeTCP16 in class Ⅱ had a high expression level during the fruit ripening stage, which indicated that it might be related to fruit ripening. The findings lay a foundation for probing into the roles of the DdeTCP gene family in the growth and development of D. delavayi.
Phylogeny ; Gene Expression Regulation, Plant ; Multigene Family ; Genome, Plant/genetics* ; Plant Proteins/genetics* ; Transcription Factors/genetics* ; Germination/genetics* ; Fruit/growth & development* ; Genes, Plant