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Abstract Surfactin is a cyclic hexalipopeptide compound, nonribosomal synthesized by representatives of the Bacillus subtilis species complex which includes B. subtilis group and its closely related species, such as B. subtilis subsp subtilis, B. subtilis subsp spizizenii, B. subtilis subsp inaquosorum, B. atrophaeus, B. amyloliquefaciens, B. velezensis (Steinke mSystems 6: e00057, 2021) It functions as a biosurfactant and signaling molecule and has antibacterial, antiviral, antitumor, and plant disease resistance properties. The Bacillus lipopeptides play an important role in agriculture, oil recovery, cosmetics, food processing and pharmaceuticals, but the natural yield of surfactin synthesized by Bacillus is low. This paper reviews the regulatory pathways and mechanisms that affect surfactin synthesis and release, highlighting the regulatory genes involved in the transcription of the srfAA-AD operon. The several ways to enhance surfactin production, such as governing expression of the genes involved in synthesis and regulation of surfactin synthesis and transport, removal of competitive pathways, optimization of media, and fermentation conditions were commented. This review will provide a theoretical platform for the systematic genetic modification of high-yielding strains of surfactin. Graphical Abstract

Abstract Background Mutations in fibrillin-1 (FBN1) are known to be associated with Marfan syndrome (MFS), an autosomal dominant connective tissue disorder. Most FBN1 mutations are missense or nonsense mutations. Traditional molecular genetic testing for the FBN1 gene, like Sanger sequencing, may miss disease-causing mutations in the gene’s regulatory regions or non-coding sequences, as well as partial or complete gene deletions and duplications. Methods Next-generation sequencing, multiplex ligation-dependent probe amplification and gap PCR were conducted on two MFS patients to screen for disease-causing mutations. Results We identified two large deletions in FBN1 from two MFS patients. One patient had a 0.23 Mb deletion (NC_000015.9:g.48550506_48779360del) including 5’UTR-exon6 of FBN1. The other patient harbored a 1416 bp deletion (NC_000015.9:g.48410869_48412284del) affecting the last exon, exon 66, of the FBN1 gene. Conclusion Our results expanded the number of large FBN1 deletions and highlighted the importance of screening for large deletions in FBN1 in clinical genetic testing, especially for those with the classic MFS phenotype.

Abstract RNF31 (HOIP), RBCK1 (HOIL-1L), and SHARPIN are subunits of the linear ubiquitin chain assembly complex. Their function and specific molecular mechanisms in hepatocellular carcinoma (HCC) have not been reported previously. Here, we investigated the role of RNF31 and RBCK1 in HCC. We showed that RNF31 and RBCK1 were overexpressed in HCC and that upregulation of RNF31 and RBCK1 indicated poor clinical outcomes in patients with HCC. RNF31 overexpression was significantly associated with more satellite foci and vascular invasion in patients with HCC. Additionally, RBCK1 expression correlated positively with RNF31 expression in HCC tissues. Functionally, RBCK1 and RNF31 promote the metastasis and growth of HCC cells. Moreover, the RNF31 inhibitor gliotoxin inhibited the malignant behavior of HCC cells. Mechanistically, RBCK1 interacted with RNF31 and repressed its ubiquitination and proteasomal degradation. In summary, the present study revealed an oncogenic role and regulatory relationship between RBCK1 and RNF31 in facilitating proliferation and metastasis in HCC, suggesting that they are potential prognostic markers and therapeutic targets for HCC.

Abstract Background Long non-coding RNAs (lncRNAs) are widely involved in the pathogenesis of cancers. However, biological roles of lncRNAs in occurrence and progression of colorectal cancer (CRC) remain unclear. The current study aimed to evaluate the expression pattern of lncRNAs and messenger RNAs (mRNAs). Methods RNA sequencing (RNA-Seq) in CRC tissues and adjacent normal tissues from 6 CRC patients was performed and functional lncRNA-mRNA co-expression network was constructed afterwards. Gene enrichment analysis was demonstrated using DAVID 6.8 tool. Reverse transcription quantitative polymerase chain reaction (RT-qPCR) was used to validate the expression pattern of differentially expressed lncRNAs. Pearson correlation analysis was applied to evaluate the relationships between selected lncRNAs and mRNAs. Results One thousand seven hundred and sixteenth differentially expressed mRNAs and 311 differentially expressed lncRNAs were screened out. Among these, 568 mRNAs were up-regulated while 1148 mRNAs down-regulated, similarly 125 lncRNAs were up-regulated and 186 lncRNAs down-regulated. In addition, 1448 lncRNA–mRNA co-expression pairs were screened out from 940,905 candidate lncRNA-mRNA pairs. Gene enrichment analysis revealed that these lncRNA-related mRNAs are associated with cell adhesion, collagen adhesion, cell differentiation, and mainly enriched in ECM-receptor interaction and PI3K-Akt signaling pathways. Finally, RT-qPCR results verified the expression pattern of lncRNAs, as well as the relationships between lncRNAs and mRNAs in 60 pairs of CRC tissues. Conclusions In conclusion, these results of the RNA-seq and bioinformatic analysis strongly suggested that the dysregulation of lncRNA is involved in the complicated process of CRC development, and providing important insight regarding the lncRNAs involved in CRC.

Non-alcoholic fatty acid liver disease (NAFLD) is a reputed global health concern, affecting children and young adults. Accumulating evidence suggests that edible fungi polysaccharides have the potential to relieve NAFLD. Our previous study found that Auricularia cornea var. Li. polysaccharides (ACP) could improve immune by regulating gut microbiota. However, its NAFLD-alleviating potentials have been scarcely reported. This study analyzed the protective effects of Auricularia cornea var. Li. polysaccharides on high-fat diet (HFD)-induced NAFLD and mechanistic actions. We first analyzed the histology and hepatic lipid profile of animals to evaluate this variant’s ameliorating effects on NAFLD. Then, antioxidant and anti-inflammatory potentials of ACP were studied. Finally, we explored changes in the gut microbiome diversity for mechanistic insights from the gut-liver region. Results showed that supplementation with ACP substantially reduced homeostasis model assessment-insulin resistance (HOMA-IR), body fat, liver index rates and weight gain (p

Sheath blight (ShB) disease, caused by Rhizoctonia solani Kühn, is one of the most serious rice diseases. Rice breeding against ShB has been severely hindered because no major resistance genes or germplasms are available in rice. Here, we report that introduction of Gastrodia antifungal protein (GAFP) genes from Gastrodia elata B1 into rice significantly enhances resistance to rice ShB. Four GAFP genes were cloned from G. elata B1, and all displayed a strong ability to inhibit R. solani growth in plate assays. Two versions, with or without a signal peptide, for each of the four GAFP genes were introduced into XD3 and R6547 rice cultivars, and all transgenic lines displayed stronger ShB resistance than the corresponding wild-type control in both greenhouse and field conditions. Importantly, GAFP2 showed the highest ShB resistance; GAFPs with and without its signal peptide showed no significant differences in enhancing ShB resistance. We also evaluated the agronomic traits of these transgenic rice and found that ectopic expression of GAFPs in rice at appropriate levels did not affect agronomic traits other than enhancing ShB resistance. Together, these results indicate that GAFP genes, especially GAFP2, have great potential in rice breeding against ShB disease.

The immuno-regulating potential of edible fungus polysaccharides has gained more and more attention. However, there is little information about the study of Auricularia cornea var. Li. polysaccharides regulating immunomodulatory activity. The objective of this work to analyze the immunomodulatory activity and the mechanism of A. cornea var. Li. polysaccharides supplementation in an immunosuppressed mice model induced by cyclophosphamide. The effects of A. cornea var. Li. polysaccharides on immune system including immune organ indices, immunoglobulin contents, and inflammation cytokines in immunosuppressed mice were determined. In addition, the regulatory effects of A. cornea var. Li. polysaccharides on the gut microbiota and their metabolites were analyzed. Results showed that A. cornea var. Li. polysaccharides significantly elevated immune organ indexes, remarkably enhanced the levels of immunoglobulin A (IgA), IgG and IgM in serum and secretory IgA (sIgA) in the intestinal mucosa, conspicuously stimulated the levels of tumor necrosis factor-α (TNF-α), interleukin-2 (IL-2), IL-4, and IL-10 in the serum. A. cornea var. Li. polysaccharides also could restore gut microbiota to the pattern that is similar with that of the control group with increase of the relative abundances of short-chain fatty acids (SCFAs)-producing bacteria. Furthermore, the content of SCFAs were increased after A. cornea var. Li. polysaccharides supplementation. This study provides useful information for applications of A. cornea var. Li. polysaccharides in immune-regulated foods and medicine.

Abstract Background N 6 -methyladenosine (m6A) is the most common RNA modification in eukaryotes and has been implicated as a novel epigenetic marker that is involved in various biological processes. The pattern and functional dissection of m6A in the regulation of several major human viral diseases have already been reported. However, the patterns and functions of m6A distribution in plant disease bursting remain largely unknown. Results We analyse the high-quality m6A methylomes in rice plants infected with two devastating viruses. We find that the m6A methylation is mainly associated with genes that are not actively expressed in virus-infected rice plants. We also detect different m6A peak distributions on the same gene, which may contribute to different antiviral modes between rice stripe virus or rice black-stripe dwarf virus infection. Interestingly, we observe increased levels of m6A methylation in rice plant response to virus infection. Several antiviral pathway-related genes, such as RNA silencing-, resistance-, and fundamental antiviral phytohormone metabolic-related genes, are also m6A methylated. The level of m6A methylation is tightly associated with its relative expression levels. Conclusions We revealed the dynamics of m6A modification during the interaction between rice and viruses, which may act as a main regulatory strategy in gene expression. Our investigations highlight the significance of m6A modifications in interactions between plant and viruses, especially in regulating the expression of genes involved in key pathways.

Rhizoctonia solani is one of the important pathogenic fungi causing several serious crop diseases, such as maize and rice sheath blight. Current methods used to control the disease mainly depend on spraying fungicides because there is no immunity or high resistance available in crops. Spraying double-strand RNA (dsRNA) for induced-gene silencing (SIGS) is a new potentially sustainable and environmentally friendly tool to control plant diseases. Here, we found that fluorescein-labelled EGFP-dsRNA could be absorbed by R. solani in co-incubation. Furthermore, three dsRNAs, each targeting one of pathogenicity-related genes, RsPG1, RsCATA, and RsCRZ1, significantly downregulated the transcript levels of the target genes after co-incubation, leading to a significant reduction in the pathogenicity of the fungus. Only the spray of RsCRZ1 dsRNA, but not RsPG1 or RsCATA dsRNA, affected fungal sclerotium formation. dsRNA stability on leaf surfaces and its efficiency in entering leaf cells were significantly improved when dsRNAs were loaded on layered double hydroxide (LDH) nanosheets. Notably, the RsCRZ1-dsRNA-LDH approach showed stronger and more lasting effects than using RsCRZ1-dsRNA alone in controlling pathogen development. Together, this study provides a new potential method to control crop diseases caused by R. solani.

This paper aims to study the seismic behavior of squat steel-reinforced concrete (SRC) shear walls with a high axial load ratio. Nine squat SRC shear walls with varying axial load ratios, steel ratios, and horizontal distributed reinforcement ratios were tested under lateral cyclic reversed loading and an axial load. The failure process, load-deformation hysteretic response, shear strength, ductility, and the strain of the specimens are reported. The results show that all the specimens failed in shear with the crushing of the web concrete. No axial failure occurred after the web concrete was crushed since the boundary elements encased with structural steel sections maintained the axial load. Larger steel ratios reduced the buckling degree of the structural steel. A larger horizontal distributed reinforcement ratio was clearly beneficial for the ductility and energy dissipation capacity of the specimen, while it had a negligible effect on the shear strength. The Chinese code provided an extremely conservative prediction of the shear strength of the tested squat SRC shear walls with a mean calculated-experimental strength ratio of 0.42. An improved formula was established mainly by the modification of the shear resistance contributed by the concrete and the structural steel, leading to a mean calculated-experimental strength ratio of 0.74. More experimental data are still needed to establish more accurate deformation acceptance criteria for SRC shear walls and to promote the performance-based seismic evaluation of SRC structures.

Many Pseudomonas protegens strains produce the antibiotics pyoluteorin (PLT) and 2,4-diacetylphloroglucinol (2,4-DAPG), both of which have antimicrobial properties. The biosynthesis of these metabolites is typically controlled by multiple regulatory factors. Virulence factor regulator (Vfr) is a multifunctional DNA-binding regulator that modulates 2,4-DAPG biosynthesis in P. protegens FD6. However, the mechanism by which Vfr regulates this process remains unclear. In the present study, chromatin immunoprecipitation of FLAG-tagged Vfr and nucleotide sequencing analysis were used to identify 847 putative Vfr binding sites in P. protegens FD6. The consensus P. protegens Vfr binding site predicted from nucleotide sequence alignment is TCACA. The qPCR data showed that Vfr positively regulates the expression of phlF and phlG, and the expression of these genes was characterized in detail. The purified recombinant Vfr bound to an approximately 240-bp fragment within the phlF and phlG upstream regions that harbor putative Vfr consensus sequences. Using electrophoretic mobility shift assays, we localized Vfr binding to a 25-bp fragment that contains part of the Vfr binding region. Vfr binding was eliminated by mutating the TACG and CACA sequences in phlF and phlG, respectively. Taken together, our results show that Vfr directly regulates the expression of the 2,4-DAPG operon by binding to the upstream regions of both the phlF and phlG genes. However, unlike other Vfr-targeted genes, Vfr binding to P. protegens FD6 does not require an intact binding consensus motif. Furthermore, we demonstrated that vfr expression is autoregulated in this bacterium. These results provide novel insights into the regulatory role of Vfr in the biocontrol agent P. protegens.

Abstract Background An economic strategy to control plant disease is to improve plant defense to pathogens by deploying resistance genes. Plant polygalacturonase inhibiting proteins (PGIPs) have a vital role in plant defense against phytopathogenic fungi by inhibiting fungal polygalacturonase (PG) activity. We previously reported that rice PGIP1 (OsPGIP1) inhibits PG activity in Rhizoctonia solani, the causal agent of rice sheath blight (SB), and is involved in regulating resistance to SB. Result Here, we report that OsPGIP2, the protein ortholog of OsPGIP1, does not possess PGIP activity; however, a few amino acid substitutions in a derivative of OsPGIP2, of which we provide support for L233F being the causative mutation, appear to impart OsPGIP2 with PG inhibition capability. Furthermore, the overexpression of mutated OsPGIP2 L233F in rice significantly increased the resistance of transgenic lines and decreased SB disease rating scores. OsPGIP2 L233F transgenic lines displayed an increased ability to reduce the tissue degradation caused by R. solani PGs as compared to control plants. Rice plants overexpressing OsPGIP2 L233F showed no difference in agronomic traits and grain yield as compared to controls, thus demonstrating its potential use in rice breeding programs. Conclusions In summary, our results provide a new target gene for breeding SB resistance through genome-editing or natural allele mining.

Abstract Background Broad-spectrum resistance gene pyramiding helps the development of varieties with broad-spectrum and durable resistance to M. oryzae. However, detailed information about how these different sources of broad-spectrum resistance genes act together or what are the best combinations to achieve broad-spectrum and durable resistance is limited. Results Here a set of fifteen different polygene pyramiding lines (PPLs) were constructed using marker-assisted selection (MAS). Using artificial inoculation assays at seedling and heading stage, combined with natural induction identification under multiple field environments, we evaluated systematically the resistance effects of different alleles of Piz locus (Pigm, Pi40, Pi9, Pi2 and Piz) combined with Pi1, Pi33 and Pi54, respectively, and the interaction effects between different R genes. The results showed that the seedling blast and panicle blast resistance levels of PPLs were significantly higher than that of monogenic lines. The main reason was that most of the gene combinations produced transgressive heterosis, and the transgressive heterosis for panicle blast resistance produced by most of PPLs was higher than that of seedling blast resistance. Different gene pyramiding with broad-spectrum R gene produced different interaction effects, among them, the overlapping effect (OE) between R genes could significantly improve the seedling blast resistance level of PPLs, while the panicle blast resistance of PPLs were remarkably correlated with OE and complementary effect (CE). In addition, we found that gene combinations, Pigm/Pi1, Pigm/Pi54 and Pigm/Pi33 displayed broad-spectrum resistance in artificial inoculation at seedling and heading stage, and displayed stable broad-spectrum resistance under different disease nursery. Besides, agronomic traits evaluation also showed PPLs with these three gene combinations were at par to the recurrent parent. Therefore, it would provide elite gene combination model and germplasms for rice blast resistance breeding program. Conclusions The development of PPLs and interaction effect analysis in this study provides valuable theoretical foundation and innovative resources for breeding broad-spectrum and durable resistant varieties.

Sheath blight (SB) caused by the soil borne pathogen Rhizoctonia solani is one of the most serious global rice diseases. Breeding resistant cultivar is the most economical and effective strategy to control the disease. However, no rice varieties are completely resistant to SB, and only a few reliable quantitative trait loci (QTLs) linked with SB resistance have been identified to date. In this study, we conducted a genome-wide association study (GWAS) of SB resistance using 299 varieties from the rice diversity panel 1 (RDP1) that were genotyped using 44 000 high-density single nucleotide polymorphism (SNP) markers. Through artificial inoculation, we found that only 36.5% of the tested varieties displayed resistance or moderate resistance to SB. In particular, the aromatic and aus sub-populations displayed higher SB resistance than the tropical japonica (TRJ), indica and temperate japonica sub-populations. Seven varieties showed similar resistance levels to the resistant control YSBR1. GWAS identified at least 11 SNP loci significantly associated with SB resistance in the three independent trials, leading to the identification of two reliable QTLs, qSB-3 and qSB-6, on chromosomes 3 and 6. Using favorable alleles or haplotypes of significantly associated SNP loci, we estimated that both QTLs had obvious effects on reducing SB disease severity and can be used for enhancing SB resistance, especially in improving SB resistance of TRJ sub-population rice varieties. These results provided important information and genetic materials for developing SB resistant varieties through breeding. Keywords: genome-wide association study, quantitative trait locus, rice, sheath blight, plant height

Sodium stannate (Na2SnO3) has been successfully prepared by a novel process of roasting cassiterite concentrates and sodium carbonate (Na2CO3) under CO−CO2 atmosphere, namely soda roasting-leaching process. However, more than 22 wt. % tin of the cassiterite was not converted into Na2SnO3 and entered the leach residues. Quartz (SiO2) is the predominant gangue in the cassiterite, and phase evolution of SnO2−SiO2−Na2CO3 system roasted under CO−CO2 atmosphere was still uncertain. In this study, the effect of SiO2 in cassiterite concentrates on preparation of Na2SnO3 was clarified. The results indicated that Na8SnSi6O18 was inevitably formed when cassiterite and Na2CO3 were roasted above 775 °C under CO−CO2 atmosphere via the reaction of SnO2 + 6SiO2 + 4Na2CO3 = Na8SnSi6O18 + 4CO2, and formation of Na8SnSi6O18 would be increased with increasing roasting temperature and Si/Sn mole fraction. In addition, it was found that Na8SnSi6O18 was insoluble in the leachate at pH value range of 1−14, which, therefore, was enriched in the leach residues. The silicon content of the cassiterite concentrates should be controlled as lower as possible to obtain a higher conversion ratio of Na2SnO3.

For a running freely land-vehicle strapdown inertial navigation system (SINS), the problems of self-calibration and attitude alignment need to be solved simultaneously. This paper proposes a complete alignment algorithm for the land vehicle navigation using Inertial Measurement Units (IMUs) and an odometer. A self-calibration algorithm is proposed based on the global observability analysis to calibrate the odometer scale factor and IMU misalignment angle, and the initial alignment and calibration method based on optimal algorithm is established to estimate the attitude and other system parameters. This new algorithm has the capability of self-initialization and calibration without any prior attitude and sensor noise information. Computer simulation results show that the performance of the proposed algorithm is superior to the extended Kalman filter (EKF) method during the oscillating attitude motions, and the vehicle test validates its advantages.

By using the methods of document literature, induction and synthesis, this paper makes a literature review and comparative study on the relevant research of school physical education laws and regulations in China and Japan. Japan is a developed country of school physical education in the world. In the process of building school physical education laws and regulations, there are some methods and ideas to solve school physical education problems. Therefore, it is of great practical significance to analyze the relevant research on Japanese school physical education laws and regulations and to sum up their experience and lessons. This paper quotes the viewpoints of Chinese and Japanese experts and scholars, and makes a literature review on the research of school physical education laws and regulations in Japan from the aspects of the course of construction of school physical education laws and regulations, the system of laws and regulations, legislation, justice, law enforcement, law abiding, content and problems, and comparative study.