New Insights into the Plutella xylostella Detoxifying Enzymes: Sequence Evolution, Structural Similarity, Functional Diversity, and Application Prospects of Glucosinolate Sulfatases.

Brassica plants have glucosinolate (GLs)-myrosinase defense mechanisms to deter herbivores. However, Plutella xylostella specifically feeds on Brassica vegetables. The larvae possess three glucosinolate sulfatases (PxGSS1-3) that compete with plant myrosinase for shared GLs substrates and produce nontoxic desulfo-GLs (deGLs). Although PxGSSs are considered potential targets for pest control, the lack of a comprehensive review has hindered the development of PxGSSs-targeted pest control methods. Recent advances in integrative multi-omics analysis, substrate-enzyme kinetics, and molecular biological techniques have elucidated the evolutionary origin and functional diversity of these three PxGSSs. This review summarizes research progress on PxGSSs over the past 20 years, covering sequence properties, evolution, protein modification, enzyme activity, structural variation, substrate specificity, and interaction scenarios based on functional diversity. Finally, we discussed the potential applications of PxGSSs-targeted pest control technologies driven by artificial intelligence, including CRISPR/Cas9-mediated gene drive, transgenic plant-mediated RNAi, small-molecule inhibitors, and peptide inhibitors. These technologies have the potential to overcome current management challenges and promote the development and field application of PxGSSs-targeted pest control.

Quantitative ubiquitylome crosstalk with proteome analysis revealed cytoskeleton proteins influence CLas pathogen infection in Diaphorina citri.

Huanglongbing (HLB), also known as citrus greening disease, is caused by Candidatus Liberbacter asiaticus (CLas) and transmitted by Diaphorina citri. Previous studies reported that CLas infection significantly influences the structure of the D. citri cytoskeleton. However, the mechanisms through which CLas manipulates cytoskeleton-related proteins remain unclear. In this study, we performed quantitative ubiquitylome crosstalk with the proteome to reveal the roles of cytoskeleton-related proteins during the infection of D. citri by CLas. Western blotting revealed a significant difference in ubiquitination levels between the CLas-free and CLas-infected groups. According to ubiquitylome and 4D label-free proteome analysis, 343 quantified lysine ubiquitination (Kub) sites and 666 differentially expressed proteins (DEPs) were identified in CLas-infected groups compared with CLas-free groups. A total of 53 sites in 51 DEPs were upregulated, while 290 sites in 192 DEPs were downregulated. Furthermore, functional enrichment analysis indicated that 18 DEPs and 21 lysine ubiquitinated proteins were associated with the cytoskeleton, showing an obvious interaction. Ubiquitination of D. citri tropomyosin was confirmed by immunoprecipitation, Western blotting, and LC-MS/MS. RNAi-mediated knockdown of tropomyosin significantly increased CLas bacterial content in D. citri. In summary, we provided the most comprehensive lysine ubiquitinome analysis of the D. citri response to CLas infection, thus furthering our understanding of the role of the ubiquitination of cytoskeleton proteins in CLas infection.

Antibody-Based Methods Reveal the Protein Expression Properties of Glucosinolate Sulfatase 1 and 2 in Plutella xylostella.

The glucosinolates (GLs) and myrosinase defensive systems in cruciferous plants were circumvented by Plutella xylostella using glucosinolate sulfatases (PxGSSs) during pest-plant interaction. Despite identifying three duplicated GSS-encoding genes in P. xylostella, limited information regarding their spatiotemporal and induced expression is available. Here, we investigated the tissue- and stage-specific expression and induction in response to GLs of PxGSS1 and PxGSS2 (PxGSS1/2) at the protein level, which shares a high degree of similarity in protein sequences. Western blotting (WB) analysis showed that PxGSS1/2 exhibited a higher protein level in mature larvae, their guts, and gut content. A significantly high protein and transcript levels of PxGSS1/2 were also detected in the salivary glands using WB and qRT-PCR. The immunofluorescence (IF) and immunohistochemistry (IHC) results confirmed that PxGSS1/2 is widely expressed in the larval body. The IHC was more appropriate than IF when autofluorescence interference was present in collected samples. Furthermore, the content of PxGSS1/2 did not change significantly under treatments of GL mixture from Arabidopsis thaliana ecotype Col-0, or commercial ally (sinigrin), 4-(methylsulfinyl)butyl, 3-(methylsulfinyl)propyl, and indol-3-ylmethyl GLs indicating that the major GLs from leaves of A. thaliana Col-0 failed to induce the expression of proteins for both PxGSS1 and PxGSS2. Our study systemically characterized the expression properties of PxGSS1/2 at the protein level, which improves our understanding of PxGSS1/2-center adaptation in P. xylostella during long-term insect-plant interaction.

Green Chemistry Based Synthesis of Zinc Oxide Nanoparticles Using Plant Derivatives of Calotropis gigantea (Giant Milkweed) and Its Biological Applications against Various Bacterial and Fungal Pathogens.

Nanotechnology is a burning field of scientific interest for researchers in current era. Diverse plant materials are considered as potential tool in green chemistry based technologies for the synthesis of metal nanoparticles (NPs) to cope with the hazardous effects of synthetic chemicals, leading to severe abiotic climate change issues in today's agriculture. This study aimed to determine the synthesis and characterization of metal-based nanoparticles using extracts of the selected plant Calotropis gigantea and to evaluate the enzyme-inhibition activities and antibacterial and antifungal activity of extracts of metal-based zinc nanoparticles using C. gigantea extracts. The crystal structure and surface morphology were characterized by X-ray diffraction (XRD) and scanning electron microscopy (SEM). C. gigantea was examined for antimicrobial activity against clinical isolates of bacteria and fungi. The water, ethanolic, and acetone extracts of C. gigantea were studied for their antagonistic action against bacterial strains (E. coli, S. aureus, P. multocida, and B. subtilis) and selected fungal strains (A. paracistic, F. solani, A. niger, S. ferrugenium, and R. nigricans). In vitro antimicrobial activity was determined by the disc diffusion method, where C. gigantea wastested for AChE and BChE inhibitory activity using Ellman's methodology. The kinetic analysis was performed by the proverbial Berthelot reaction for urease inhibition. The results showed that out of all the extracts tested, ethanolic and water extracts possessed zinc nanoparticles. These extracts showed the maximum zone of inhibition against F. solani and P. multocida and the lowest against S. ferrugenium and B. subtilis. A potential source of AChE inhibitors is certainly provided by the abundance of plants in nature. Numerous phyto-constituents, such as AChE and BChE inhibitors, have been reported in this communication. Water extract was active and has the potential for in vitro AChE and BChE inhibitory activity. The urease inhibition with flower extracts of C. gigantea revealed zinc nanoparticles in water extracts that competitively inhibited urease enzymes. In the case of cholinesterase enzymes, it was inferred that the water extract and zinc nanoparticles have more potential for inhibition of BChE than AChE and urease inhibition. Furthermore, zinc nanoparticles with water extract are active inthe inhibition of the bacterial strains E. coli, S. aureus, and P. multocida and the fungal strains A. paracistic, F. solani, and A. niger.

Recent advances in bioremediation of heavy metals and persistent organic pollutants: A review.

Heavy metals and persistent organic pollutants are causing detrimental effects on the environment. The seepage of heavy metals through untreated industrial waste destroys the crops and lands. Moreover, incineration and combustion of several products are responsible for primary and secondary emissions of pollutants. This review has gathered the remediation strategies, current bioremediation technologies, and their primary use in both in situ and ex situ methods, followed by a detailed explanation for bioremediation over other techniques. However, an amalgam of bioremediation techniques and nanotechnology could be a breakthrough in cleaning the environment by degrading heavy metals and persistant organic pollutants.

Short Neuropeptide F and Its Receptor Regulate Feeding Behavior in Pea Aphid (Acyrthosiphon pisum).

Insect short neuropeptide F (sNPF), an ortholog of prolactin-releasing peptide of invertebrates, regulates diverse biological processes, including feeding, olfaction, locomotion, and sleep homeostasis in insects. However, its function is still unclear in an important model insect and agricultural pest, the pea aphid (Acyrthosiphon pisum). Here, we investigated short neuropeptide F (ApsNPF) and its receptor (ApsNPFR) in A. pisum. The sNPF gene contains three exons and two long introns. In addition, the genome contains a single sNPF receptor with seven transmembrane domains. Stage- and tissue-specific transcript profiling by qRT-PCR revealed that ApsNPF and ApsNPFR were mainly expressed in the central nervous system. The receptor was also detected in antennae, midgut, and integument. The highest expression levels were found in first instar nymphs compared to other developmental stages. Besides, the starvation-induced pattern indicated that the sNPF network depends on the nutritional state of the insect. An electrical penetration graph showed that probing time and phloem duration of A. pisum on broad bean plants decreased in response to dssNPF and dssNPFR in RNAi assays. sNPF silencing reduced the number of nymphs per female but not aphid survival. We believe that our results advance in-depth knowledge of the sNPF/sNPFR signaling cascade and its place in regulating feeding behavior in insects. In turn, it may contribute to the potential design of new strategies to control aphids, with a focus on the sNPF system.

Host-Plant Variations Affect the Biotic Potential, Survival, and Population Projection of Myzus persicae (Hemiptera: Aphididae).

The green peach aphid, Myzus persicae Sulzer (Hemiptera: Aphididae), a polyphagous insect pest is a major threat to a wide range of crops worldwide. Aiming to evaluate the life history traits of M. persicae, feeding on different host plants, we used five vegetables: cabbage, Brassica oleracea (Brassicaceae); chinese cabbage, B. rapa (Brassicaceae); chili pepper, Capsicum annum (Solanaceae); crown daisy, Chrysanthemum coronarium (Asteraceae); and eggplant, Solanum melongena (Solanaceae). TWOSEX-MSchart software was used for the statistical analysis about the age-stage, two-sex life table theory. The highest fecundity (69.65 individuals) rate of M. persicae, intrinsic rate of increase (r = 0.425 d-1), finite rate of increase (λ = 1.531 d-1), net reproductive rate (R0 = 69.65 offspring), and shortest mean generation time (T = 9.964 d) were recorded on the chili pepper plant. Whereas, lower fitness occurred on cabbage. The findings attained from population growth parameters indicate that chili pepper is the most susceptible plant, while cabbage is resistant to aphids. Population projection results also supported this statement, as the final total population size on cabbage was significantly lower than other plants. The reported information would be useful for devising integrated pest management programs, particularly those involving M. persicae. This information also suggests the adaptability of M. persicae causing economic damage to these vegetable cultivars.