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Summary Corn leaf aphids (Rhopalosiphum maidis) are highly destructive pests of maize (Zea mays) that threaten growth and seed yield, but resources for aphid resistance are scarce. Here, we identified an aphid‐resistant maize mutant, resistance to aphids 1 (rta1), which is allelic to LIGULELESS1 (LG1). We confirmed LG1's role in aphid resistance using the independent allele lg1‐2, allelism tests and LG1 overexpression lines. LG1 interacts with, and increases the stability of ZINC‐FINGER PROTEIN EXPRESSED IN INFLORESCENCE MERISTEM (ZIM1), a central component of the jasmonic acid (JA) signalling pathway, by disturbing its interaction with the F‐box protein CORONATINE INSENSITIVE 1a (COI1a). Natural variation in the LG1 promoter was associated with aphid resistance among inbred lines. Moreover, a loss‐of‐function mutant in the LG1‐related gene SPL8 in the dicot Arabidopsis thaliana conferred aphid resistance. This study revealed the aphid resistance mechanism of lg1, providing a theoretical basis and germplasm for breeding aphid‐resistant crops. [ABSTRACT FROM AUTHOR]

Few studies have been conducted on the effect of nonamine groups on the nanopore environment and gas adsorption/separation ability of normal spherical hyper-crosslinked resins. Here, hyper-crosslinked resins (HCP@COOH and HCP@CO), modified with a COOH-containing structure (A) and a CO-containing structure (B), were synthesized by the Friedel–Crafts acylation reaction. According to static adsorption and dynamic separation tests, different oxygen-containing groups have different impacts on the nanopore diameter and small gas adsorption/separation behavior. Structure (A), benefiting from its suitable nanoscale size, was verified to be effective in narrowing the size of nanopores to 1–2 nm and increasing the adsorption capacity of CO2, CH4, and CO, while Structure (B) seems to have a positive influence only on CH4. The uptake of CO2 and the separation ratio of CO2/CO in HCP@COOH reach 32 cm3/g and 12.2, respectively, at 298 K and 1 bar. The IAST selectivity of CH4/CO in HCP@O-1 is up to 3.4, increasing from 1.9 for HCP-1. HCP@COOH can separate syngas efficiently at ambient temperature and can be regenerated by simple vacuum operation. The interaction mechanism was also analyzed by experiments and electrostatic potential simulation. [ABSTRACT FROM AUTHOR]

Porcine deltacoronavirus (PDCoV) is an emerging swine coronavirus that causes severe diarrhea to pigs of all ages, especially the suckling piglets under one-week-old. We previously isolated a highly pathogenic PDCoV strain, CZ2020, from a diarrheal piglet and have passaged it for over 100 passages. The adaptability of the CZ2020 increased gradually in vitro as the passage increased. Amino acid mutations were observed in pp1a, pp1ab, spike, envelop, and membrane proteins, and the spike protein accounts for 66.7% of all amino acid mutations. Then, the high passage strains, CZ2020-F80 and CZ2020-F100, were selected for evaluation of the pathogenicity in three-day-old piglets to examine whether these amino acid changes affected their virulence. At 2 days postchallenge (DPC), 2/5 piglets started to show typical diarrhea, and at 4 DPC, severe diarrhea was observed in the CZ2020-challenged piglets. Viral RNA could be detected at 1 DPC in rectal swabs and reached its highest at 4 DPC in the CZ2020-challenged group. CZ2020-F80- and CZ2020-F100-challenged groups have one piglet exhibiting mild diarrhea at 4 and 6 DPC, respectively. Compared with the CZ2020-challenged group, the piglets in CZ2020-F80- and F100-challenged groups had lower viral loads in rectal swabs, intestines, and other organs. No obvious histopathological lesions were observed in the intestines of CZ2020-F80- and F100-challenged piglets. Virulent PDCoV infection could also induce strong interferons and proinflammatory cytokines in vitro and in vivo. These data indicate that the strains, CZ2020-F80 and CZ2020-F100, were significantly attenuated via serial passaging in vitro and have the potential for developing attenuated vaccine candidates. [ABSTRACT FROM AUTHOR]

Four nonfluorinated and fluorinated nanoporous polymers [PAN-5H, PAN-5F, PAN-2F, and PAN-2-(CF3)] were synthesized from a triazine-based tetramine with benzaldehyde, pentafluorobenzaldehyde, 3,5-difluorobenzaldehyde, and 3,5-bis-(trifluoromethyl)-benzaldehyde, respectively. It is interestingly found that the porosity parameters and selective adsorptions of CO2 and light hydrocarbons strongly depend not only on the number and kind of fluorine atoms and fluorinated groups, but also on the substituted position on the phenyl rings in the fluorinated porous polymers. Relative to PAN-5H and PAN-5F, PAN-2F, and PAN-2-(CF3) with phenyls meta-substituted by two fluorinated groups exhibit considerably increased BET surface areas from 502 to 1269 m2/g. At 298 K and 1 bar, the uptakes of C3H8, C2H6, and C2H4 in PAN-2F reach 4.62, 3.64, and 3.20 mmol/g, respectively, whereas PAN-5F exhibits the highest adsorption selectivities of C3H8/CH4 (372.3), C3H8/CO2 (33.2), C2H6/CH4 (21.8), C3H8/C2H6 (9.4), and CO2/CH4 (7.1) among the four polymers. The dynamic breakthrough experiments demonstrate that the mixed gases of C2H6/C2H4, C3H8/CH4, C2H6/CH4, and CO2/CH4 can be separated by the fluorinated polymers under ambient condition. The achieved results are significant for understanding the effects of fluorine-functionalization on the separation of ethylene and CO2 from light hydrocarbons in nanoporous polymers. [ABSTRACT FROM AUTHOR]

ABSTRACT During their co‐evolution with herbivorous insects, plants have developed multiple defense strategies that resist pests, such as releasing a blend of herbivory‐induced plant volatiles (HIPVs) that repel pests or recruit their natural enemies. However, the responses of insects to HIPVs in maize (Zea mays L.) are not well understood. Here, we demonstrate that the Asian corn borer (ACB, Ostrinia furnacalis), a major insect pest of maize, shows a preference for maize pre‐infested with ACB larvae rather than being repelled by these plants. Through combined transcriptomic and metabolomics analysis of ACB‐infested maize seedlings, we identified two substances that explain this behavior: (E)‐4,8‐dimethylnona‐1,3,7‐triene (DMNT) and (3E,7E)‐4,8,12‐trimethyltrideca‐1,3,7,11‐tetraene (TMTT). DMNT and TMTT attracted ACB larvae, and knocking out the maize genes responsible for their biosynthesis via gene editing impaired this attraction. External supplementation with DMNT/TMTT hampered the larvae's ability to locate pre‐infested maize. These findings uncover a novel role for DMNT and TMTT in driving the behavior of ACB. Genetic modification of maize to make it less detectable by ACB might be an effective strategy for developing maize germplasm resistant to ACB and for managing this pest effectively in the field. [ABSTRACT FROM AUTHOR]

The precise role of the highly variable coronavirus S protein in modulating innate immune responses remains unclear. In this study, we demonstrated that the mutant strain of swine coronavirus porcine enteric diarrhea virus induced significantly lower levels of double-stranded RNA (dsRNA) accumulation, inhibited protein kinase R (PKR) activation and suppressed stress granule (SG) formation compared with the classical strain. The 29th amino acid at N-terminus of S was identified as the key functional site for regulation of SG formation, and found that mutant S inhibited PKR phosphorylation and SG formation by upregulating adenosine deaminase acting on RNA 1 (ADAR1)-p150. Notably, the Zα domain of ADAR1-p150 was essential for inhibiting SG formation. Upregulation of ADAR1-p150 also reduced accumulation of dsRNA depending on its RNA editing function. Virus rescue confirmed that the mutant carrying a substitution at amino acid 29 failed to induce ADAR1-p150, leading to dsRNA accumulation, PKR activation and SG formation. Interestingly, the latest severe acute respiratory syndrome coronavirus-2 strains exhibit a novel 25PPA27 deletion at N-terminus of S that was also shown to lead to altered ADAR1-p150 expression and SG inhibition. The transcription factor TCF7L2 was identified as a player in S-mediated transcriptional enhancement of ADAR1-p150. This study is the first to clarify the crucial role of N-terminus of S in immune regulation of coronaviruses., (© The Author(s) 2024. Published by Oxford University Press on behalf of Nucleic Acids Research.)

Variant Porcine epidemic diarrhea virus (PEDV), which causes diarrhea and high mortality in piglets, has become a major pathogen, and co-epidemics of different subtypes of the virus have become a very thorny problem for the clinical prevention and control of PEDV. However, cross-protection between epidemic G2a and G2b subtype strains has not been observed, and there is currently no vaccine against both G2a and G2b strains. In this study, we demonstrate the low cross-protection between G2a and G2b strains with piglet immunization and challenge tests. The trimeric full-length S proteins of G2a and G2b variants were purified and a bivalent subunit vaccine against PEDV G2a/G2b-S was developed. In active and passive immune protection tests, the bivalent subunit vaccine produced high neutralizing antibody titers and S-specific immunoglobulin G (IgG) and IgA titers against both the G2a and G2b strains in piglets and sows. In the attack phase of the viruses, the clinical symptoms and microscopic lesions in the immunized groups were significantly alleviated. Importantly, the PEDV G2a/G2b-S bivalent subunit vaccine conferred effective passive immunity against PEDV G2a and G2b challenges in the form of colostrum-derived antibodies from the immunized sows. In conclusion, our data demonstrate the low cross-protection of PEDV epidemic G2a and G2b strains and show that the G2a/G2b-S bivalent subunit vaccine is protective against both G2a and G2b strains. It is therefore a candidate vaccine for PEDV prevention., Importance: The detection rate of PEDV G2a subtype strains is currently increasing. Although commercial vaccines are available, most vaccines do not exert an ideal protective effect against these strains. Furthermore, there is no definitive research into the cross-protection between G2a and G2b strains, and no bivalent vaccine provides joint protection against both. Therefore, in this study, we investigated the cross-protection between PEDV G2a and G2b strains and designed a candidate bivalent subunit vaccine combining the trimeric S proteins of the G2a and G2b subtypes. We demonstrate that the cross-protection between strains G2a and G2b is poor and that this bivalent subunit vaccine protects piglets from viral attack by inducing both active and passive immunity. This study emphasizes the effectiveness of the PEDV G2a/G2b-S bivalent subunit vaccine and provides a feasible method for the development of efficient PEDV vaccines., Competing Interests: The authors declare no conflict of interest.

We describe a method to test the preference of insects in response to (3E)-4,8-dimethyl-1,3,7-nonatriene (DMNT). We use a device that includes a horizontal glass tube, two grooves (with activated carbon), air flow, rubber stoppers/tubes, transparent glass containers (optional), and a holder for the glass tube (optional). Equal amounts of activated carbon in the groove (removable) are placed at both ends to avoid air contamination. The air flow is generated by an air pump. In the closed device, different samples are placed at each end of the glass tube. The air pump at the top of the glass tube forms an air flow that converges to the middle site of the glass tube. In each test, insect larvae are located in the middle of the glass test tube. If the test samples release DMNT that can be sensed by insects, the insects will selectively move to one specific end of the glass tube. The number of insects that move to each end will be recorded for further studies. This method can also be used to test the preference of insects in response to other volatile compounds., Competing Interests: Competing interestsThe authors declare no conflicts of interest., (Copyright © The Authors; exclusive licensee Bio-protocol LLC.)