A universal design of restructured dimer antigens: Development of a superior vaccine against the paramyxovirus in transgenic rice.

The development of vaccines, which induce effective immune responses while ensuring safety and affordability, remains a substantial challenge. In this study, we proposed a vaccine model of a restructured "head-to-tail" dimer to efficiently stimulate B cell response. We also demonstrate the feasibility of using this model to develop a paramyxovirus vaccine through a low-cost rice endosperm expression system. Crystal structure and small-angle X-ray scattering data showed that the restructured hemagglutinin-neuraminidase (HN) formed tetramers with fully exposed quadruple receptor binding domains and neutralizing epitopes. In comparison with the original HN antigen and three traditional commercial whole virus vaccines, the restructured HN facilitated critical epitope exposure and initiated a faster and more potent immune response. Two-dose immunization with 0.5 µg of the restructured antigen (equivalent to one-127th of a rice grain) and one-dose with 5 µg completely protected chickens against a lethal challenge of the virus. These results demonstrate that the restructured HN from transgenic rice seeds is safe, effective, low-dose useful, and inexpensive. We provide a plant platform and a simple restructured model for highly effective vaccine development.

Impact of Varying the Photoanode/Catalyst Interfacial Composition on Solar Water Oxidation: The Case of BiVO4(010)/FeOOH Photoanodes.

Photoanodes used in a water-splitting photoelectrochemical cell are almost always paired with an oxygen evolution catalyst (OEC) to efficiently utilize photon-generated holes for water oxidation because the surfaces of photoanodes are typically not catalytic for the water oxidation reaction. Suppressing electron-hole recombination at the photoanode/OEC interface is critical for the OEC to maximally utilize the holes reaching the interface for water oxidation. In order to explicitly demonstrate and investigate how the detailed features of the photoanode/OEC interface affect interfacial charge transfer and photocurrent generation for water oxidation, we prepared two BiVO4(010)/FeOOH photoanodes with different Bi:V ratios at the outermost layer of the BiVO4 interface (close to stoichiometric vs Bi-rich) while keeping all other factors in the bulk BiVO4 and FeOOH layers identical. The resulting two photoanodes show striking differences in the photocurrent onset potential and photocurrent density for water oxidation. The ambient pressure X-ray photoelectron spectroscopy results show that these two BiVO4(010)/FeOOH photoanodes show drastically different Fe2+:Fe3+ ratios in FeOOH both in the dark and under illumination with water, demonstrating the immense impact of the interfacial composition and structure on interfacial charge transfer. Using computational studies, we reveal the effect of the surface Bi:V ratio on the hydration of the BiVO4 surface and bonding with the FeOOH layer, which in turn affect the band alignments between BiVO4 and FeOOH. These results explain the atomic origin of the experimentally observed differences in electron and hole transfer and solar water oxidation performance of the two photoanodes having different interfacial compositions.

Rice-produced classical swine fever virus glycoprotein E2 with herringbone-dimer design to enhance immune responses.

Pestiviruses, including classical swine fever virus, remain a concern for global animal health and are responsible for major economic losses of livestock worldwide. Despite high levels of vaccination, currently available commercial vaccines are limited by safety concerns, moderate efficacy, and required high doses. The development of new vaccines is therefore essential. Vaccine efforts should focus on optimizing antigen presentation to enhance immune responses. Here, we describe a simple herringbone-dimer strategy for efficient vaccine design, using the classical swine fever virus E2 expressed in a rice endosperm as an example. The expression of rE2 protein was identified, with the rE2 antigen accumulating to 480 mg/kg. Immunological assays in mice, rabbits, and pigs showed high antigenicity of rE2. Two immunizations with 284 ng of the rE2 vaccine or one shot with 5.12 µg provided effective protection in pigs without interference from pre-existing antibodies. Crystal structure and small-angle X-ray scattering results confirmed the stable herringbone dimeric conformation, which had two fully exposed duplex receptor binding domains. Our results demonstrated that rice endosperm is a promising platform for precise vaccine design, and this strategy can be universally applied to other Flaviviridae virus vaccines.

Selective scandium ion capture through coordination templating in a covalent organic framework.

The use of coordination complexes within covalent organic frameworks can significantly diversify the structures and properties of this class of materials. Here we combined coordination chemistry and reticular chemistry by preparing frameworks that consist of a ditopic (p-phenylenediamine) and mixed tritopic moieties-an organic ligand and a scandium coordination complex of similar sizes and geometries, both bearing terminal phenylamine groups. Changing the ratio of organic ligand to scandium complex enabled the preparation of a series of crystalline covalent organic frameworks with tunable levels of scandium incorporation. Removal of scandium from the material with the highest metal content subsequently resulted in a 'metal-imprinted' covalent organic framework that exhibits a high affinity and capacity for Sc3+ ions in acidic environments and in the presence of competing metal ions. In particular, the selectivity of this framework for Sc3+ over common impurity ions such as La3+ and Fe3+ surpasses that of existing scandium adsorbents.

Prenatal EGCG consumption causes obesity and perturbs glucose homeostasis in adult mice.

Epigallocatechin gallate (EGCG) has a wide consumption for its health advantages. The current study investigates the effects of prenatal EGCG administration on glucose metabolism and obesity in adulthood. Pregnant C57BL/6J mice were supplemented with EGCG in drinking water (3 µg/mL) for 16 d. Abdominal obesity was observed in both male and female adult mice, which was associated with the upregulation of adipose-specific genes, including C/ebpα and Srebf1 (Srebf1 only in males), and the downregulation of genes related to lipolysis, such as Acox1, Atgl and Pdk4 (only in males) in visceral adipose tissue. Elevated fasting glucose levels and hyperinsulinemia were observed in adult males, while females exhibit lower glucose level in glucose tolerance test, which might be due to reduced glucagon levels. Though hepatic expression of the insulin receptor signaling pathway was upregulated in males and was not altered in females, prenatal treatment with EGCG downregulated the expression of this signaling pathway in the skeletal muscle of adult mice, which was further demonstrated in primary human skeletal muscle cells treated with EGCG. The methylation levels in promotor of genes related to the insulin receptor signaling were matched with their transcription in mice, while the expression of acetylated histones was downregulated in human skeletal muscle cells. These results suggest that EGCG consumption during pregnancy should be a risk factor for the disruption of glucose homeostasis in adulthood.

Characterization of Neutralizing Monoclonal Antibodies and Identification of a Novel Conserved C-Terminal Linear Epitope on the Hemagglutinin Protein of the H9N2 Avian Influenza Virus.

The H9N2 avian influenza virus (AIV) remains a serious threat to the global poultry industry and public health. The hemagglutinin (HA) protein is an essential protective antigen of AIVs and a major target of neutralizing antibodies and vaccines. Therefore, in this study, we used rice-derived HA protein as an immunogen to generate monoclonal antibodies (mAbs) and screened them using an immunoperoxidase monolayer assay and indirect enzyme-linked immunosorbent assay. Eight mAbs reacted well with the recombinant H9N2 AIV and HA protein, four of which exhibited potent inhibitory activity against hemagglutination, while three showed remarkable neutralization capacities. Western blotting confirmed that two mAbs bound to the HA protein. Linear epitopes were identified using the mAbs; a novel linear epitope, 480HKCDDQCM487, was identified. Structural analysis revealed that the novel linear epitope is located at the C-terminus of HA2 near the disulfide bond-linked HA1 and HA2. Alignment of the amino acid sequences showed that the epitope was highly conserved among multiple H9N2 AIV strains. The results of this study provide novel insights for refining vaccine and diagnostic strategies and expand our understanding of the immune response against AIV.

Long-term exposure to environmental levels of phenanthrene induces emaciation-thirst disease-like syndromes in female mice.

Phenanthrene (Phe) is a polycyclic aromatic hydrocarbon widely present in foods and drinking water. To explore the detrimental effects of Phe on body metabolism, female Kunming mice were treated with Phe in drinking water at concentrations of 0.05, 0.5 and 5 ng/mL. After exposure for 270 d, the animals exhibited dose-dependent reduced body weight and increased water consumption. The dose-dependent accumulation of Phe in the brain decreased hypothalamic neuron numbers, upregulated hypothalamic expression of anaplastic lymphoma kinase, elevated norepinephrine levels in white adipose tissue (WAT) and further activated lipolysis in WAT, leading to a reduction in fat mass. Brown adipose tissue formation was reduced, accompanied by the inhibition of the bone morphogenetic protein signaling pathway. A simultaneous reduced serum levels of antidiuretic hormone (arginine vasopressin) might be one of the reasons for increased water consumption. The present results indicate an environmental etiology and prevention way for the development of emaciation-thirst disease.

An Improved Immunochromatographic Strip Based on Plant-Derived E2 for Detection of Antibodies against Classical Swine Fever Virus.

Vaccination is an effective method to control the spread of classical swine fever virus (CSFV), which is a major cause of economic losses to the swine industry. Although serological detection assays are commonly used to assess immune status, current methods for monitoring of antibodies (Abs) are time-consuming, expensive, and require cell culture and virus manipulation. To address these problems, the E2 protein of CSFV was expressed in transgenic rice seeds as a labeled antigen for the development of an immunochromatographic test strip (ICTS) for rapid, precise, and cost-effective detection of Abs. The ICTS has a reasonable sensitivity of 1:128,000 for detection of serum Abs against CSFV and no cross-reactivity with Abs of other porcine viruses. The similarity of the results between the proposed ICTS and a commercial enzyme-linked immunosorbent assay was 94.1% (128/136) for detection of serum Abs from immunized animals and 92.3% (72/78) for detection of maternally derived Abs. The proposed assay was successfully used to monitor Abs against E2 of both pigs and rabbits immunized with a live attenuated vaccine or an E2 subunit vaccine. The results confirmed that the ICTS can be applied to detect Ab levels in animals with different immunological backgrounds. The ICTS based on plant-derived E2 is a relatively inexpensive, rapid, and accurate assay for detection of Abs against CSFV and avoids the risk of contamination by animal products. IMPORTANCE The E2 protein of classical swine fever virus (CSFV) was expressed in transgenic rice endosperms as a diagnostic antigen for use with a rapid colloidal gold assay for the detection of antibodies (Abs) against CSFV. This improved test was used to monitor Abs against the E2 protein in both pigs and rabbits immunized with a live attenuated vaccine or E2 subunit vaccine. The assay successfully detected Ab levels in serum samples from piglets with different immunological backgrounds. In contrast to current E2 protein-based diagnostic methods using Escherichia coli or insect cells as expression systems, plant-derived E2 avoids the limitations of low immunogenicity of eukaryotic expression systems and potential contamination of fetal bovine serum with bovine viral diarrhea virus in cell culture.

EGCG exposure during pregnancy affects uterine histomorphology in F1 female mice and the underlying mechanisms.

Although epigallocatechin-3-gallate (EGCG), the major polyphenol in green tea, has been shown to have many benefits, the effect of EGCG exposure in utero on adult uterine development is unclear. In this study, pregnant C57BL/6 mice were exposed to 1 mg/kg body weight (bw) EGCG dissolved in drinking water from gestational days 0.5-16.5. A significant decrease in uterine weight was observed in the adult female mice, accompanied by uterine atrophy, inflammation, and fibrosis in the endometrium. Uterine atrophy was attributed to the thinning of the endometrial stromal layer and a significant reduction in endometrial cell proliferation. The expression levels of related proteins in the NF-κB and RAF/MEK/ERK signaling pathways were significantly increased, which might be responsible for the occurrence of inflammation. Activation of the transforming growth factor beta (TGF-ß1)/Smad signaling pathway might be involved in the development of endometrial fibrosis. The changes in the expression of estrogen receptor α, ß (ERα, ERß), progesterone receptor (PGR), and androgen receptor (AR) might lead to changes in the aforementioned signaling pathways. The promoter region methylation level of Esr2 was increased, and the expression of DNMT3A was evaluated. Our study indicates a risk of EGCG intake during pregnancy affecting uterine development in offspring.

[Expression of NDV HN protein in rice and development of a semi-quantitative rapid method for detection of antibodies].

The aim of this study was to develop a semi-quantitative immunochromatographic method for rapid detection of Newcastle disease virus (NDV) antibodies by expressing HN protein in rice endosperm bioreactor. The recombinant plasmid pUC57-HN was digested by MlyⅠ and XhoⅠ to retrieve the HN gene, while the intermediate vector pMP3 containing promoter, signal peptide and terminator was digested by NaeⅠ and XhoⅠ. The HN gene and the linearized pMP3 were purified and ligated to form a recombinant plasmid pMP3-HN1. Subsequently, pMP3-HN1 and plant vector pCAMBIA1300 were digested by EcoRⅠ and Hind Ⅲ, and the HN1 gene was cloned into pCAMBIA1300. The recombinant plasmid pCAMBIA1300-HN1 was introduced into Agrobacterium tumefaciens EHA105 by electrotransformation, and the pCAMBIA1300-HN1 was transferred into rice callus by agrobacterium-mediated method. After dark culture, callus screening, differentiation, rooting and transplanting, transgenic rice seeds were obtained 4 months later. PCR identified that the HN gene has been inserted into the rice genome. SDS-PAGE and Western blotting indicated that the HN protein was successfully expressed in the positive rice endosperm. The purity of the HN protein was more than 90% by SP cation exchange chromatography and gel filtration chromatography. According to the national standards for the diagnostic techniques of Newcastle disease HI test (HI≥4log2, positive antibody reaction), a colloidal gold labeled purified HN protein was used to prepare a semi-quantitative test strip by double-antibody sandwich method for rapid detection of NDV antibody. The results showed that the test strip did not cross-react with positive sera against other viruses, and the sensitivity of the test strip reached 1:102 400 for standard positive sera of Newcastle disease. Testing of a total of 308 clinical sera showed that the compliance rate of the test strip with HI test was 97.08%, and the Kappa value was 0.942. In conclusion, high purity recombinant HN protein was obtained from rice endosperm, and a simple, rapid, highly sensitive and highly specific semi-quantitative immunochromatographic strip was developed. The test strip could be used for immune evaluation of the Newcastle disease vaccine.

Prenatal EGCG exposure-induced heart mass reduction in adult male mice and underlying mechanisms.

Epigallocatechin-3-gallate (EGCG), which is a major polyphenol in tea, has an unclear effect on cardiac development. In the present study, mice (C57BL/6) were exposed in utero to EGCG dissolved in drinking water (3 µg/ml) for 16 days. A significant decrease in the heart/body weight ratio was observed in adult males but not in adult females. The protein expression levels of TGF-ß1 and its downstream transcription factors SMAD3 and SMAD4 were significantly decreased in male hearts. The PI3K/AKT signaling pathway was inhibited, the expression of proapoptotic proteins, such as BAX, Cleaved Caspase3 and Cleaved Caspase9, was elevated, and the level of antiapoptotic proteins, such as BCL-2, was decreased. A reduced heart/body weight ratio may be associated with the loss of cardiac fibers and an increase in myocardial apoptosis. The cardiac levels of aromatic hydrocarbon receptor and androgen receptor were elevated only in males, which may explain the sexual dimorphism in the effects. The promoter methylation levels of pik3r1, tgf-ß, smad4 were elevated, and those of ahr were reduced, explaining the mechanism underlying the cardiac histological alteration caused by prenatal exposure to EGCG. The results suggest that ingestion of EGCG during pregnancy may be a risk factor for cardiac development in offspring.

In utero exposure to mixed PAHs causes heart mass reduction in adult male mice.

Polycyclic aromatic hydrocarbons (PAHs) are a risk factor for the occurrence of cardiac diseases. The present study was conducted to investigate the influence of prenatal exposure to a mixed PAHs on heart and the underlying mechanism. Pregnant mice were orally administered with a mixture of 8 kinds of PAHs (0, 5, 50, 500 µg/kg body weight) once every 2 days for a total of 8 dosages. The mixed PAHs contained naphthalene, acenaphthylene, phenanthrene, fluoranthene, pyrene, benzo[a]pyrene, dibenzo[a,h]anthracene and benzo[g,h,i]perylene at a weight ratio of 10: 10: 10: 10: 10: 1: 1: 1. The adult males, not females, showed significantly decreased heart/body weight ratio, which was attributed to the loss of cardiac fiber and the increase of cell apoptosis. The protein expression of transforming growth factor ß1 and its downstream transcription factors, Smad3 and Smad4, was significantly downregulated, which caused the loss of cardiac fiber. The downregulated phosphatidylinositol 3-kinase and AKT led to increased expression of caspase3, caspase9, BAX and reduced expression of Bcl-2, which was responsible for the increased cell apoptosis. Different levels of aromatic hydrocarbon receptor and sex hormone receptors between males and females were associated with the distinct effect on heart.

A novel linear epitope at the C-terminal region of the classical swine fever virus E2 protein elicits neutralizing activity.

Classical swine fever virus (CSFV) is a member of the genus Pestivirus, which causes serious economic losses. The re-emergence of the disease in Japan in 2018 has increased awareness of CSFV. In this study, Balb/c mice were immunized with plant-derived E2 protein, and four monoclonal antibodies (mAbs) 4B11, 7B3, 11A5 and 6F3 were generated. Two of these mAbs, 4B11 and 7B3, effectively blocked CSFV infection of PK-15 cells. Both mAbs recognized a novel linear epitope, 256CLIGNTTVKVHASDER271. The neutralizing ability of anti-CSFV serum decreased 63%, when pre-incubated with the linear peptide at 200 µg/mL. Structural analysis showed that this linear epitope is present at the border of Domain C and Domain D on the surface of the E2 protein. Alignment of amino acid sequences showed that the epitope was conserved in different subgroups of CSFV but not in other members of the Pestivirus genus. Consistently with the analysis above, this epitope distinguished antibodies against CSFV from those against bovine viral diarrhea virus (BVDV). Our study provides an ideal candidate peptide for new vaccine design and differential diagnosis of CSFV. These findings will contribute to the control and eradication of classical swine fever.

Lessons learned from first-principles calculations of transition metal oxides.

Transition metal oxides (TMOs) are an important class of materials with diverse applications, ranging from memristors to photoelectrochemical cells. First-principles calculations are critical for understanding these complex materials at an atomic level and establishing relationships between atomic and electronic structures, particularly for probing quantities difficult or inaccessible to experiment. Here, we discuss computational strategies used to understand TMOs by focusing on two examples, a photoanode material, BiVO4, and an oxide for low-power electronics, La1-xSrxCoO3. We highlight key aspects required for the modeling of TMOs, namely, the descriptions of how oxygen vacancies, extrinsic doping, the magnetic state, and polaron formation impact their electronic and atomic structures and, consequently, many of the observed properties.

Long-term exposure to environmental levels of phenanthrene disrupts spermatogenesis in male mice.

Phenanthrene (Phe) is a tricyclic polycyclic aromatic hydrocarbon with high bioavailability under natural exposure. However, there are few studies on the reproductive toxicity of Phe in mammals. In this study, male Kunming mice were gavaged once every two days with Phe (5, 50, and 500 ng/kg) for 28 weeks. The accumulation levels of Phe in the testis were dose-dependently increased. Histopathological staining showed that Phe exposure reduced the number of spermatogonia, sperm and Sertoli cells. The percentage of testicular apoptotic cells was significantly increased, which was further verified by the upregulated BAX protein. The expression of the GDNF/PI3K/AKT signaling pathway was downregulated, which might suppress the self-renewal and differentiation of spermatogonial stem cells. Meanwhile, Phe exposure inhibited the expression of Sertoli cell markers (Fshr, WT1, Sox9) and the Leydig cell marker Cyp11a1, indicating damage to the function of Sertoli cells and Leydig cells. Serum estrogen and testicular estrogen receptor alpha were significantly upregulated, while androgen receptor expression was downregulated. These alterations might be responsible for impaired spermatogenesis. This study provides new insights for evaluating the reproductive toxicity and potential mechanisms of Phe in mammals.

Maternal exposure to phenanthrene during gestation disturbs glucose homeostasis in adult mouse offspring.

Epidemiological studies have indicated that polycyclic aromatic hydrocarbons were related to diabetes and insulin resistance. However, studies in mammals on the development of diabetes caused by polycyclic aromatic hydrocarbons are lacking. Pregnant mice were orally exposed to phenanthrene (0, 60 and 600 µg kg-1 body weight) once every 3 days during gestation. In adult mouse offspring, in-utero phenanthrene exposure caused glucose intolerance and decreased insulin levels in females, while caused elevated fasting blood glucose and insulin levels in males. Serum resistin and interleukin-6 levels were elevated in offspring of both sexes. Serum adiponectin levels were decreased in females but increased in males. The insulin receptor signals were upregulated in the liver and downregulated in the skeletal muscle of F1 females, while they were inhibited in both tissues of F1 males. The visceral fat weight and body weight of the treated mice were not increased, suggesting that phenanthrene is not an obesogen, which is supported by the nonsignificant alteration in pparγ transcription in visceral adipose tissue. The transcription of retn in visceral adipose tissue was upregulated in both sexes, and that of adipoq was downregulated in females but upregulated in males, which were matched with the promoter methylation levels of these genes. The results indicated that phenanthrene exposure during gestation could disturb adipocytokine levels via epigenetic modification in adult offspring, and further influence glucose metabolism. These results might be helpful for understanding nonobesogenic pollutant-induced insulin resistance and preventing against diabetes without obesity.

Somatic mutations in genes associated with mismatch repair predict survival in patients with metastatic cancer receiving immune checkpoint inhibitors.

Immune checkpoint inhibitors (ICIs) have emerged as one of the most promising therapeutic options for patients with advanced cancer. The aim of the present study was to investigate the prognostic value of somatic mutations in mismatch repair (MMR) genes in metastatic cancers after ICI treatment, as well as their association with tumor mutational burden (TMB). Information regarding gene mutations in mismatch repair and the survival time of patients with advanced cancer following ICI treatment was collected from the cBioPortal database. The prognostic value of somatic mutations in MMR genes and the association between the mutation status and TMB score were analyzed among multiple types of cancer. Somatic mutation frequency in the MMR genes was identified to be 7% among all patients, which varied across different types of cancer. Somatic mutations in the MMR genes were associated with improved overall survival time in all tested patients (P=0.004). Following stratification by type of ICI treatment, a significant association was observed between somatic mutations in the MMR genes and overall survival time in patients treated with cytotoxic T-lymphocyte-associated protein 4 inhibitors (P=0.01). In addition, marked but non-significant association between somatic mutations in the MMR genes and overall survival time was revealed in patients administered with programmed death-1/programmed death-ligand-1 inhibitors (P=0.09). Multivariate Cox proportional hazards regression analysis demonstrated that somatic mutations in MMR genes were significantly associated with overall survival time (hazard ratio, 0.683; 95% confidence interval, 0.497-0.938; P=0.01). Patients with somatic mutations in the MMR genes demonstrated higher TMB compared with those not harboring mutations (P<0.01). The results of the present study suggested that somatic mutations in the MMR genes may be used as a prognostic marker of a positive outcome in patients with metastatic cancer receiving ICI treatment, since somatic mutations in the MMR genes may be one of the main factors affecting the tumor mutation load.

In utero exposure to phenanthrene induces hepatic steatosis in F1 adult female mice.

Environmental pollutants are thought to be a risk factor for the prevalence of hepatic steatosis. Polycyclic aromatic hydrocarbons (PAHs) are ubiquitous, and human exposure is inevitable. In the present study, phenanthrene (Phe) was used as a representative PAH to investigate the effects of in utero exposure to PAH on hepatic lipid metabolism and the toxicological mechanism involved. Pregnant mice (C57BL/6J) were orally administered Phe (0, 60, 600 and 6000 µg kg-1 body weight) once every 3 days with 6 doses in total. F1 female mice aged 125 days showed significantly elevated hepatic lipid levels in the liver. The protein expression of hepatic peroxisome proliferator-activated receptors (PPARß and PPARγ) and retinoid X receptors (RXRs) was upregulated; the transcription of genes related to lipogenesis, such as srebp1 (encoding sterol regulatory element binding proteins), acca (acetyl-CoA carboxylase), fasn (fatty acid synthase) and pcsk9 (proprotein convertase subtilisin/kexin type 9), showed an upregulation, while the mRNA levels of the lipolysis gene lcat (encoding lecithin cholesterol acyl transferase) were downregulated. These results could be responsible for lipid accumulation. The promoter methylation levels of pparγ were reduced and were the lowest in the 600 µg kg-1 group, and the promoter methylation levels of lcat were significantly increased in all the Phe treatments. These changes were matched with the alterations in their mRNA levels, suggesting that prenatal Phe exposure could induce abnormal lipid metabolism in later life via epigenetic modification.

Genomic and epigenomic EBF1 alterations modulate TERT expression in gastric cancer.

Transcriptional reactivation of telomerase catalytic subunit (TERT) is a frequent hallmark of cancer, occurring in 90% of human malignancies. However, specific mechanisms driving TERT reactivation remain obscure for many tumor types and in particular gastric cancer (GC), a leading cause of global cancer mortality. Here, through comprehensive genomic and epigenomic analysis of primary GCs and GC cell lines, we identified the transcription factor early B cell factor 1 (EBF1) as a TERT transcriptional repressor and inactivation of EBF1 function as a major cause of TERT upregulation. Abolishment of EBF1 function occurs through 3 distinct (epi)genomic mechanisms. First, EBF1 is epigenetically silenced via DNA methyltransferase, polycomb-repressive complex 2 (PRC2), and histone deacetylase activity in GCs. Second, recurrent, somatic, and heterozygous EBF1 DNA-binding domain mutations result in the production of dominant-negative EBF1 isoforms. Third, more rarely, genomic deletions and rearrangements proximal to the TERT promoter remobilize or abolish EBF1-binding sites, derepressing TERT and leading to high TERT expression. EBF1 is also functionally required for various malignant phenotypes in vitro and in vivo, highlighting its importance for GC development. These results indicate that multimodal genomic and epigenomic alterations underpin TERT reactivation in GC, converging on transcriptional repressors such as EBF1.

Porous Organic Frameworks Featured by Distinct Confining Fields for the Selective Hydrogenation of Biomass-Derived Ketones.

The asymmetric hydrogenation of biomass-derived molecules for the preparation of single enantiomer compounds is an effective method to reduce the rapid consumption of fossil resources. Porous organic frameworks (POFs) with pure organic surfaces may provide unusual confinement effects for organic substrates in chiral catalysis. Here, a series of POF catalysts are designed with chiral active centers decorated into sharply defined one-dimensional channels with diameters in the range of 1.2-2.9 nm. Due to the synergistic effect originating from the conjugated inner wall, the POF material (aperture size 2.4 nm) concentrates over 90% of aromatic species into the porous architecture, and its affinity is one or two orders of magnitude higher than those of classical porous solids. As determined by PBE+D3 calculation, the phenyl fragment reveals strong π-π interaction for steric hindrance around the metal active site to achieve stronger asymmetric induction. Therefore, this POF catalyst achieves high conversion (>99% yield) and enantioselectivity (>99% ee) for various substrates. The advantages of using the POF platform as a chiral catalyst can provide new perspectives on POF-based solid-state host-guest chemistry and asymmetric heterogeneous catalysis.