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The vegetative insecticidal protein Vip3Aa from Bacillus thuringiensis (Bt) has been produced by transgenic crops to counter pest resistance to the widely used crystalline (Cry) insecticidal proteins from Bt. To proactively manage pest resistance, there is an urgent need to better understand the genetic basis of resistance to Vip3Aa, which has been largely unknown. We discovered that retrotransposon-mediated alternative splicing of a midgut-specific chitin synthase gene was associated with 5,560-fold resistance to Vip3Aa in a laboratory-selected strain of the fall armyworm, a globally important crop pest. The same mutation in this gene was also detected in a field population. Knockout of this gene via CRISPR/Cas9 caused high levels of resistance to Vip3Aa in fall armyworm and 2 other lepidopteran pests. The insights provided by these results could help to advance monitoring and management of pest resistance to Vip3Aa. The insecticidal protein Vip3Aa is used in genetically engineered crops to overcome pest resistance to other insecticidal transgenes. This study shows that insertion of a transposable element into a gut-specific chitin synthase gene causes Vip3Aa resistance in field-collected individuals of the lepidopteran pest Spodoptera frugiperda (fall armyworm). [ABSTRACT FROM AUTHOR]

BACKGROUND: With the increasing incidence of pest resistance to transgenic crops producing Bacillus thuringiensis (Bt) proteins in the field, elucidating the molecular basis of resistance is important for monitoring, delaying and countering pest resistance. Previous work revealed that mutation or down‐regulated expression of the cadherin gene (PgCad1) is associated with pink bollworm (Pectinophora gossypiella) resistance to Cry1Ac, and 20 mutant PgCad1 alleles (r1‐r20) were characterized. Here, we tested the hypothesis that the ABC transporter PgABCC2 is a functional receptor for the Bt toxin Cry1Ac and that a mutation is associated with resistance. RESULTS: We identified and characterized the first resistance allele (rC2) of PgABCC2 in the laboratory‐selected Cry1Ac‐resistant strain AQ‐C2 of pink bollworm. The rC2 allele had a one‐base deletion in exon20, resulting in a frameshift and the introduction of a premature stop codon. This resulting PgABCC2 protein had a truncated C‐terminus, including the loss of the NBD2 domain. AQ‐C2 exhibited 20.2‐fold greater resistance to Cry1Ac than the susceptible strain, and its inheritance of Cry1Ac resistance was recessive and genetically linked to PgABCC2. When produced in cultured insect cells, recombinant wild‐type and rC2 mutant PgABCC2 proteins localized within the cell plasma membrane, although substantial cytoplasmic retention was also observed for the mutant protein, while the mutant PgABCC2 caused a 13.9‐fold decrease in Cry1Ac toxicity versus the wild‐type PgABCC2. CONCLUSIONS: PgABCC2 is a functional receptor of Cry1Ac and the loss of its carboxyl terminus (including its NBD2 domain) confers low‐level resistance to Cry1Ac in both larvae and in cultured cells. © 2024 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

A study published in the journal Clinical & Translational Medicine suggests that analyzing microbial communities could be a useful tool for diagnosing and predicting the prognosis of pancreatic tumors. The researchers examined fecal and intratumor microbial samples from patients with pancreatic tumors and healthy volunteers. They discovered that specific bacteria in fecal samples could potentially serve as non-invasive biomarkers for early detection of pancreatic tumors. Furthermore, they observed differences in the microbial composition of pancreatic tissues between malignant and non-malignant tumors. These findings indicate that microbial profiling may offer a promising approach for improving the early detection and treatment of pancreatic tumors. [Extracted from the article]

Rice blast, caused by the fungus Magnaporthe oryzae, and brown planthopper (BPH) infestation are two of the most destructive problems of rice production in China. The development of multi-resistant varieties is widely recognized as the most efficient and environmentally friendly approach to controlling crop diseases and pests. Functional molecular markers (FMMs) have been developed from functional variants in the genic region associated with trait variation, greatly enhancing the efficiency of identifying and pyramiding valuable genes in crop breeding. In this study, two FMMs and a multiplex PCR amplification system were developed for two major broad-spectrum BPH resistance genes, Bph6 and Bph9. With the assistance of FMMs in the multi-resistant rice restorer-line development pipeline, two lines (Huahui7713 and Huahui3006) with blast and BPH resistance were developed by pyramiding three resistance genes Pigm, Bph6 and Bph9. Two new hybrid rice varieties, Weiliangyou7713 and Xuanliangyou3006, derived from Huahui7713 and Huahui3006, have been developed and commercialized in China. Weiliangyou7713 and Xuanliangyou3006 exhibit enhanced resistance to both blast and BPH, while maintaining optimal yield and grain quality. The adoption of Weiliangyou7713 continues to expand, now being cultivated on a large scale, which is promising for its future role in reducing the dependence on chemical fungicides and pesticides in rice production. This suggests that the implementation of Huahui7713 and Huahui3006 in targeted breeding programs could be highly beneficial for developing rice varieties with strong resistance to blast and BPH. [ABSTRACT FROM AUTHOR]

In recent years, jamming strategies for Synthetic Aperture Radar (SAR) pertaining to target detection and identification, such as the creation of false targets, electromagnetic (EM) deception, and signal spoofing, have been increasingly emphasized. Distinct from traditional SAR jamming approaches, the introduction of an innovative artificial material cloak in SAR target jamming presents augmented capabilities. These methods demonstrate a proficient redirection of incident EM waves in specific or arbitrary directions, effectively masking the vital information linked to critical targets. This study introduces a broadband SAR target jamming system employing an information metasurface that incorporates intelligent information processing algorithms in conjunction with a space-time-coding digital metasurface, endowing it with the capacity to adeptly modulate incident EM waves. This integration facilitates a versatile approach to jamming, enabling the deployment of multi-mode protective measures against critical targets. The conducted simulation and experiment results validate the system's ability to adjustably produce EM deception and generate multiple false targets independently of the SAR system. The outcomes of this research significantly advance the practicality of SAR protection strategies, pushing the boundaries toward more dynamic, broadband, and controllable scenarios, thereby substantially improving the concealment of critical targets in highly sensitive conflict areas. [ABSTRACT FROM AUTHOR]

Biomass-based carbon materials exhibit remarkable potential for electromagnetic wave (EMW) pollution protection due to their extremely low density, inconceivable structure, and exceptional dielectric loss properties. In this study, a biomass-derived electromagnetic absorber (EMA) was developed using Juncus effusus (JE), and the 3D hierarchical porous framework was well maintained during a simple carbonization process, achieving a reflection loss (RL) value of −40.4 dB and a broad effective absorption bandwidth (EAB) of 3.48 GHz for JE-700 at the thickness of merely 1.75 mm. Besides, the maximum radar cross-section (RCS) reduction value of 32.4 dB m2 was achieved at an incident angle of 0°. The synergistic effects of multiple loss mechanisms for the JE-derived EMA include conduction loss arising from the carbonized skeleton, multi-reflection of EMWs in regularly arranged micro-triangle units and hollow skeletons, and the numerous interfacial polarizations associated with boundary-type defects present in the amorphous and graphite phase carbon, as well as between the microelements (P, K, and Si) and carbon atoms. Therefore, the inherent 3D hierarchical porous framework offers novel inspirations and insights for designing biomass-derived EMAs. [ABSTRACT FROM AUTHOR]