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Ex vivo lens epithelial explant cultures created through a technique that mimics cataract surgery provided an ideal model with which to compare the impacts on proteoglycan expression in the response to wounding in both reparative‐promoting and pro‐fibrotic microenvironments. On their native basement membrane capsule, the injured lens epithelium undergoes regenerative repair, with the wound closing within a few days. Their migration across the wound area is led by a population of activated lens resident immune cells. The same leader cell population also directs the wounded epithelium to migrate off the outside edges of the lens explant across the surrounding tissue culture dish, where a pro‐fibrotic matrix microenvironment is produced that signals the resident immune cells at the leading edge to acquire a myofibroblast phenotype. We separated the wounded lens explants from those cells on the surrounding culture substrate at different times points over 3 days post‐wounding and performed an unbiased RNAseq analysis to identify the changes in proteoglycan expression from time 0 in the environment in which regenerative repair takes place and compared those results to the impact on proteoglycan expression when the same cell populations encountered the microenvironment where fibrosis is induced. In both environments, there were changes in the expression of proteoglycans associated with promoting cell migration. However, the greatest changes in proteoglycan expression occurred in the fibrosis‐inducing environment, which included a subset of SLRPs with known functions in signaling the activation of TGFβ and in mediating collagen fibrillogenesis. The RNAseq results also revealed that in the pro‐fibrotic microenvironment, there is an induction of cell surface proteoglycans that are associated with mechanotransduction signaling events linked to their role in the assembly of integrin focal adhesion contacts.

The main problem in cassava production is the low productivity, as often manifested in the limited number of tubers produced. It was expected that wounding treatments at different growth periods, in addition to mycorrhiza inoculation, would also have an effect on cassava production. This study was aimed to determine the effect of stem wounding frequency and period on quality of cassava-mycorrhiza symbiosis and cassava yield. This study was conducted using a single factor Randomized Complete Block Design (RCBD) consisting of four application methods: (A) no wounding; (B) 1 time wounding before planting; (C) 2 times wounding before and after planting; (D) 3 times wounding before and after planting. Each treatment was repeated three times (12 experimental units in total). The variables observed include (1) percentages of mycorrhiza infections and number of spores, (2) root growth and (3) cassava yield. The results showed that wounding frequency and period were found to be effective in increasing the cassava root surface, as well as increasing the mycorrhiza infection, which resulted in the increase of cassava yield (54.32 tonnes/ha). The wounding frequency of one to three times on cassava gave significant difference compared to control treatment. Three times wounding treatment prior to planting resulted in the highest cassava yield improvement of 54.05%.

The identity of the cell files necessary for the leaf-to-leaf transmission of wound signals plants has been debated for decades. In Arabidopsis, wounding initiates the glutamate receptor-like (GLR)–dependent propagation of membrane depolarizations that lead to defense gene activation. Using a vein extraction procedure we found pools of GLR-fusion proteins in endomembranes in phloem sieve elements and/or in xylem contact cells. Strikingly, only double mutants that eliminated GLRs from both of these spatially separated cell types strongly attenuated leaf-to-leaf electrical signaling. glr3.3 mutants were also compromised in their defense against herbivores. Since wounding is known to cause increases in cytosolic calcium, we monitored electrical signals and Ca2+ transients simultaneously. This revealed that wound-induced membrane depolarizations in the wild-type preceded cytosolic Ca2+ maxima. The axial and radial distributions of calcium fluxes were differentially affected in each glr mutant. Resolving a debate over which cell types are necessary for electrical signaling between leaves, we show that phloem sieve elements and xylem contact cells function together in this process.

Land plants are exposed to not only biotic stresses such as pathogen infection and herbivore wounding, but abiotic stresses such as cold, heat, drought, and salt. Elaborate strategies have been developed to avoid or abide the adverse effects, with unsaturated fatty acids (UFAs) emerging as general defenders. In higher plants, the most common UFAs are three 18-carbon species, namely, oleic (18:1), linoleic (18:2), and α-linolenic (18:3) acids. These simple compounds act as ingredients and modulators of cellular membranes in glycerolipids, reserve of carbon and energy in triacylglycerol, stocks of extracellular barrier constituents (e.g., cutin and suberin), precursors of various bioactive molecules (e.g., jasmonates and nitroalkenes), and regulators of stress signaling. Nevertheless, they are also potential inducers of oxidative stress. In this review, we will present an overview of these roles and then shed light on genetic engineering of FA synthetic genes for improving plant/crop stress tolerance.

The long fingers of one hand are bound in a tie just below the collar. Pozzi says: “I would like to teach the young doctors who will train at this clinic how to examine the sick so as not to scare them, how to examine them without needlessly wounding their modesty, and how to talk to them in words which, according to the occasion, might need to be indulgent or severe, but without either over-familiarity or harshness”. [...]at the medical student ball, in “scenes of ‘orgiastic splendour’”, Pozzi stands as though about to make a speech but, writes Barnes, “he takes advantage of the opportunity to reach down into the crowd, hoist a naked girl up on to the stage, kiss her full on the mouth, and then, turning to the rioting crowd, make a gesture as if to say ‘Do as I do.’”

Plants respond to stress by releasing biogenic volatile organic compounds (BVOCs). Green leaf volatiles (GLVs), which are abundantly produced across the plant kingdom, comprise an important group within the BVOCs. They can repel or attract herbivores and their natural enemies; and they can induce plant defences or prime plants for enhanced defence against herbivores and pathogens and can have direct toxic effects on bacteria and fungi. Unlike other volatiles, GLVs are released almost instantly upon mechanical damage and (a)biotic stress and could thus function as an immediate and informative signal for many organisms in the plant’s environment. We used a meta-analysis approach in which data from the literature on GLV production during biotic stress responses were compiled and interpreted.We identified that different types of attackers and feeding styles add a degree of complexity to the amount of emitted GLVs, compared with wounding alone. This meta-analysis illustrates that there is less variation in the GLV profile than we presumed, that pathogens induce more GLVs than insects and wounding, and that there are clear differences in GLV emission between monocots and dicots. Besides the meta-analysis, this review provides an update on recent insights into the perception and signalling of GLVs in plants.

Wounding stress leads to anthocyanin accumulation. However, the underlying molecular mechanism remains elusive. In this study, MdWRKY40 was found to promote wounding-induced anthocyanin biosynthesis in association with MdMYB1 and undergo MdBT2-mediated degradation in apple. We found that MdMYB1, a positive regulator of anthocyanin biosynthesis, was essential for the wounding-induced anthocyanin biosynthesis in apple. MdWRKY40 was identified as an MdMYB1-interacting protein, and enhanced the binding of MdMYB1 to its target genes in response to wounding. We found that MdBT2 interacted physically with MdWRKY40 and was involved in its degradation through the 26S proteasome pathway. Our results demonstrate that MdWRKY40 is a key modulator in the wounding-induced anthocyanin biosynthesis, which provides new insights into the regulation of wounding-induced anthocyanin biosynthesis at both the transcriptional and post-translational levels in apple.

Calcium ion (Ca(2+) ) signalling triggered by insect herbivory is an intricate network with multiple components, involving positive and negative regulators. Real-time, noninvasive imaging of entire Arabidopsis thaliana rosettes was employed to monitor cytosolic free calcium ([Ca(2+) ]cyt ) elevations in local and systemic leaves in response to wounding and Spodoptera littoralis feeding. Luminescence emitted by the cytosol-localized Ca(2+) reporter aequorin was imaged using a high-resolution photon-counting camera system. Spodoptera littoralis feeding on Arabidopsis induced both local and systemic [Ca(2+) ]cyt elevations. Systemic [Ca(2+) ]cyt signals were found predominantly in adjacent leaves with direct vascular connections to the treated leaf and appeared with a delay of 1 to 2 min. Simulated herbivory by wounding always induced a local [Ca(2+) ]cyt response, but a systemic one only when the midrib was wounded. This systemic [Ca(2+) ]cyt response was suppressed by the presence of insect-derived oral secretions as well as in a mutant of the vacuolar cation channel, Two Pore Channel 1 (TPC1). Our results provide evidence that in Arabidopsis insect herbivory induces both local and systemic [Ca(2+) ]cyt signals that distribute within the vascular system. The systemic [Ca(2+) ]cyt signal could play an important signalling role in systemic plant defence.

The application of postharvest abiotic stresses is an effective strategy to activate the primary and secondary metabolism of plants inducing the accumulation of antioxidant phenolic compounds. In the present study, the effect of water stress applied alone and in combination with wounding stress on the activation of primary (shikimic acid) and secondary (phenylpropanoid) metabolic pathways related with the accumulation of phenolic compound in plants was evaluated. Carrot (Daucus carota) was used as model system for this study, and the effect of abiotic stresses was evaluated at the gene expression level and on the accumulation of metabolites. As control of the study, whole carrots were stored under the same conditions. Results demonstrated that water stress activated the primary and secondary metabolism of carrots, favoring the lignification process. Likewise, wounding stress induced higher activation of the primary and secondary metabolism of carrots as compared to water stress alone, leading to higher accumulation of shikimic acid, phenolic compounds, and lignin. Additional water stress applied on wounded carrots exerted a synergistic effect on the wound-response at the gene expression level. For instance, when wounded carrots were treated with water stress, the tissue showed 20- and 14-fold increases in the relative expression of 3-deoxy-D-arabino-heptulosanate synthase and phenylalanine ammonia-lyase genes, respectively. However, since lignification was increased, lower accumulation of phenolic compounds was detected. Indicatively, at 48 h of storage, wounded carrots treated with water stress showed ~31% lower levels of phenolic compounds and ~23% higher lignin content as compared with wounded controls. In the present study, it was demonstrated that water stress is one of the pivotal mechanism of the wound-response in carrot. Results allowed the elucidation of strategies to induce the accumulation of specific primary or secondary metabolites when plants are treated with water stress alone or when additional water stress is applied on wounded tissue. If the accumulation of a specific primary or secondary metabolite were desirable, it would be recommended to apply both stresses to accelerate their biosynthesis. However, strategies such as the use of enzymatic inhibitors to block the carbon flux and enhance the accumulation of specific compounds should be designed.

Non-lethal kinetic projectiles have the potential to cause excessive harm or fatalities when fired from a close range. To address this issue, a 18.4 mm non-lethal frangible kinetic projectile was designed. The projectile uses polymethyl methacrylate (PMMA) as the shell material and it is filled with oleoresin capsicum (OC) powder as an incapacitating agent. Gelatine was selected as the material for the human simulant target, and LS-DYNA software was employed to conduct numerical simulations of the impact process of both the frangible kinetic projectile and the Type-97 18.4 mm rubber projectile on the target. The simulations analysed the projectile velocity, displacement, and pressure changes within the target by comparing the wounding effectiveness. Using the multiparameter synchronous measurement technology, experiments were conducted to impact a target using both types of projectiles. The results showed that the numerical simulations were consistent with the experimental observations, effectively reproducing the projectile impact process and wounding effects. Compared to a traditional rubber projectile, the frangible kinetic projectile reduced the initial velocity and kinetic energy upon impact. By fragmenting upon impact, the projectile increased the contact area, absorbed part of the impact energy, increased the duration of the effect of the impact, and decreased both the displacement of the projectile and the peak internal pressure within the target, resulting in a more gradual pressure change. When used in close-range shooting, the projectile shell breaks to release the OC powder, achieving personnel control through chemical stimulation and avoiding fatal injuries to the target. This research provides theoretical references and technical support for the optimised design of non-lethal weapon systems. •A non-lethal frangible kinetic projectile is designed.•Numerical simulations are conducted on the impact process of frangible kinetic projectiles and the Type −97 18.4 mm rubber projectiles against gelatin targets, and the injury effects are compared.•Results from the numerical simulation are virtually consistent with experimental results.•The non-lethal frangible kinetic projectile can release internal OC powder upon the fragmentation of its casing, utilizing chemical stimulation to achieve personnel control while avoiding fatal injuries to the target.