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The emerging SARS-CoV-2 variants, commonly with many mutations in S1 subunit of spike (S) protein are weakening the efficacy of the current vaccines and antibody therapeutics. This calls for the variant-proof SARS-CoV-2 vaccines targeting the more conserved regions in S protein. Here, we designed a recombinant subunit vaccine, HR121, targeting the conserved HR1 domain in S2 subunit of S protein. HR121 consisting of HR1–linker1–HR2–linker2–HR1, is conformationally and functionally analogous to the HR1 domain present in the fusion intermediate conformation of S2 subunit. Immunization with HR121 in rabbits and rhesus macaques elicited highly potent cross-neutralizing antibodies against SARS-CoV-2 and its variants, particularly Omicron sublineages. Vaccination with HR121 achieved near-full protections against prototype SARS-CoV-2 infection in hACE2 transgenic mice, Syrian golden hamsters and rhesus macaques, and effective protection against Omicron BA.2 infection in Syrian golden hamsters. This study demonstrates that HR121 is a promising candidate of variant-proof SARS-CoV-2 vaccine with a novel conserved target in the S2 subunit for application against current and future SARS-CoV-2 variants.

Juvenile hormone esterase (JHE) is a key enzyme for insects, playing an important role in the regulation of insect growth, development, diapause and reproduction. We identified a complete putative JHE of Cydia pomonella(CpJHE-like) which is comprised of a 1 761 bp coding sequence (CDS) encoding 587 amino acid residues from the transcriptome data. The deduced protein sequence of CpJHE-like showed the highest identity of 60.44% with the Adoxophyes honmaiJHE (AhJHE) and the minimal identity of 25.81% with Aedes aegyptiJHE (AaJHE). CpJHE-like exhibited all the seven typical motifs of the functional JHEs and had the highly consistent tertiary structure with Manduca sextaJHE (MsJHE). Phylogenetic analysis showed that the CpJHE-like was close to two JHEs from the family Tortricidae. The CpJHE-liketranscript level take a leap in the 3-day-old fifth instar larva, increased about 300-fold compared to the basal level. Tissue-specific expression profile showed that the CpJHE-liketranscript was expressed mainly in the fat body. This study indicates that the CpJHE-like is the functional JHE, which may play vital roles in the development and reproduction of C. pomonella.

AbstractSixty-one endophytic fungus strains with different colony morphologies were isolated from the leaves, stems and roots of Tephrosia purpureawith colonization rates of 66.95%, 37.50%, and 26.92%, respectively. Based on internal transcribed spacer sequence analysis, 61 isolates were classified into 16 genera belonging to 3 classes under the phylum Ascomycota. Of the 61 isolates, 6 (9.84%) exhibited antifungal activity against one or more indicator plant pathogenic fungi according to the dual culture test. Isolate TPL25 had the broadest antifungal spectrum of activity, and isolate TPL35 was active against 5 plant pathogenic fungi. Furthermore, culture filtrates of TPL25 and TPL35 exhibited greater than 80% growth inhibition against Sclerotinia sclerotiorum. We conclude that the endophytic fungal strains TPL25 and TPL35 are promising sources of bioactive compounds.

Maize (Zea maysL.) is one of the world's major food crops, and often suffers from tremendous yield loss caused by abiotic stresses. The MADS-box genes are known to play versatile roles in plants, controlling plant responses to multiple abiotic stresses. However, understanding of regulation of their expressions by the conventional loss-of-function approach is very difficult. So far, regulation of MADS-box gene expression is little known. The best approach to retrieve expression regulation of this category of genes is to characterize expression of their promoters. In this study, the promoter of a homolog (GenBank accession no. EC864166) of maize MADS-box gene m18was cloned by way of genome-walking PCR, named Pro66. Predicative analysis indicated that Pro66 contains more than one TATA box and multiple cis-acting environmental conditions-responsive elements (ECREs). Pro66 could drive expression of the β-glucuronidase (GUS)-encoding gene in maize, and heterologous expression of GUS in red pepper stressed by water deficit, salt, copper, iron deficiency, heat, cold, and grown under short and long photoperiods, echoing predicative ECREs. Conclusively, maize MADS-box gene m18likely plays versatile functions in maize response to multiple abiotic stresses due to the promoter with multiple cis-acting elements. The complex arrangement of multiple cis-acting elements in the promoter features meticulously regulated expression of m18.The results give informative clues for heterologous utilisation of the promoters in monocot and dicot species. The copy of the ECREs and heterologous expression of the promoter in dicot species are also discussed.

Hydraulic fracturing is one of the effective means to enhance coal bed methane production for vertical wells. This paper presents an approach that uses pseudo-3D fracture propagation model to study the influence of petrophysical properties, differential stress, treatment conditions, etc. on fracture geometry. It is shown that differential stress, pump rate is proportional to fracture length and width; elastic modulus, Poisson`s ratio, pump rate, etc. is proportional to fracture height. The finding is of great importance for acquiring ideal fracture geometry.

ß-Lapachone is an ortho naphthoquinone, originally isolated from a tree whose extract has been used medicinally for centuries. Recent investigations suggest its potential application against numerous diseases. Its lethality at micromolar (μm) concentrations against a variety of cancer cells in culture indicates its potential against tumor growth. A few experiments with positive results have been performed that apply the compound to tumors growing in animals. Particularly promising is the remarkably powerful synergistic lethality between ß-lapachone and taxol against several tumor cell lines implanted into mice; the mice did not appear to be adversely affected. Enhanced lethality of X-rays and alkylating agents to tumor cells in culture was reported when ß-lapachone was applied during the recovery period, because of inhibition of DNA lesion repair. Clinical trials are still to be initiated. The detailed mechanism of cell death induced by ß-lapachone remains for investigation. DNA topoisomerase I was the first biochemical target of ß-lapachone to be discovered, although its role in cell death is not clear. A proposed mechanism of cell death is via activation of a futile cycling of the drug by the cytoplasmic two-electron reductase NAD(P) H: quinone oxidoreductase, also known as NQO1, DTdiaphorase and Xip3. Death of NQO1 expressing cells is prevented by the NQO1 inhibitor dicoumarol, and cells with low NQO1 are resistant. At higher drug concentrations the production of reactive oxygen species (ROS) appears to be responsible. Furthermore, this process is p53- and caspase- independent. Either apoptotic or necrotic cell death can result, as reported in various studies performed under differing conditions. ß-Lapachone is one of a few novel anticancer drugs currently under active investigation, and it shows promise for chemotherapy alone and especially in combinations.

Background: There are two fundamental forms of cell death: apoptosis and necrosis. Molecular studies of cell death thus far favor a model in which apoptosis and necrosis share very few molecular regulators. It appears that apoptotic processes triggered by a variety of stimuli converge on the activation of a member of the caspase family, such as caspase 3, which leads to the execution of apoptosis. It has been suggested that blocking of caspase activation in an apoptotic process may divert cell death to a necrotic demise, suggesting that apoptosis and necrosis may share some upstream events. Activation of caspase is preceded by the release of mitochondrial cytochrome C. Materials and Methods: We first studied cell death induced by β-lapachone by MTT and colony-formation assay. To determine whether the cell death induced by β-lapachone occurs through necrosis or apoptosis, we used the PI staining procedure to determine the sub-G1 fraction and the Annexin-V staining for externalization of phophatidylserine. We next compared the release of mitochondrial cytochrome C in apoptosis and necrosis. Mitochondrial cytochrome C was determined by Western blot analysis. To investigate changes in mitochondria that resulted in cytochrome C release, the mitochondrial membrane potential (delta psi) was analyzed by the accumulation of rhodamine 123, a membrane-permeant cationic fluorescent dye. The activation of caspase in apoptosis and necrosis were measured by using a profluorescent substrate for caspase-like proteases, PhiPhiLuxG6D2. Results: β-lapachone induced cell death in a spectrum of human carcinoma cells, including nonproliferating cells. It induced apoptosis in human ovary, colon, and lung cancer cells, and necrotic cell death in four human breast cancer cell lines. Mitochondrial cytochrome C release was found in both apoptosis and necrosis. This cytochrome C release occurred shortly after β-lapachone treatment when cells were fully viable by trypan blue exclusion and MTT assay, suggesting that cytochrome C release is an early event in β-lapachone induced apoptosis as well as necrosis. The mitochondrial cytochrome C release induced by β-lapachone is associated with a decrease in mitochondrial transmembrane potential (delta psi). There was activation of caspase 3 in apoptotic cell death, but not in necrotic cell death. This lack of activation of CPP 32 in human breast cancer cells is consistent with the necrotic cell death induced by β-lapachone as determined by absence of sub-G1 fraction, externalization of phosphatidylserine. Conclusions: β-lapachone induces either apoptotic or necrotic cell death in a variety of human carcinoma cells including ovary, colon, lung, prostate, and breast, suggesting a wide spectrum of anti-cancer activity in vitro. Both apoptotic and necrotic cell death induced by β-lapachone are preceded by a rapid release of cytochrome C, followed by the activation of caspase 3 in apoptotic cell death but not in necrotic cell death. Our results suggest that β-lapachone is a potential anti-cancer drug acting on the mitochondrial cytochrome C-caspase pathway, and that cytochrome C is involved in the early phase of necrosis.

Parasite biodiversity of fish in coral reefs of the South China Sea is still incompletely explored. We describe here a new species of Neohexostoma(Monogenea: Hexostomatidae) from the gill filaments of the dogtooth tuna Gymnosarda unicolor(Scombridae), collected off Yongshu Reef, South China Sea. Neohexostoma gymnosardaen. sp. is distinguished from its congeners by the following features: (i) haptor clearly marked from body proper by a strongly constricted peduncle, divided in its posterior margin into two symmetrical lobes, (ii) vagina armed with scattered small blunt spines, (iii) eggs tied by their long polar filaments, (vi) esophagus with several lateral diverticula, (v) intestinal ceca unfused and extending into the haptor. We present an analysis of the relationships of this monogenean based on partial 28S rDNA sequences. An identification key for species of Neohexostomais provided. This is the first member of the genus Neohexostomaknown to parasitize a species of Gymnosarda.

Paracaesicolan. gen., is erected herein to accommodate a new microcotylid species, Paracaesicola nanshaensisn. sp., collected from the Yongshu Reef, South China Sea. This species is the first monogenean to be recorded from the gills of Paracaesio sordida. The new species is characterized by the following features: (i) haptor short, with clamps arranged in two equal bilateral rows; (ii) testes numerous, arranged in two roughly alternating longitudinal rows, extending into the haptor; (iii) genital atrium armed with 16 robust spines, which are vertically arranged on top of the sausage shaped muscular male copulatory organ; and (iv) single vagina, bottle-shaped, with a distinctly bulbous vaginal atrium. The terminals of the reproductive system discriminate Paracaesicolan. gen. from all other genera in the Microcotylidae. Molecular phylogenetic analyses, based on partial 28S rDNA, places Paracaesicola nanshaensisn. sp. within the microcotylid clade, but its sequence differs from all known available microcotylid sequences.