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The plant cell wall has a diversity of functions. It provides a structural framework to support plant growth and acts as the first line of defense when the plant encounters pathogens. The cell wall must also retain some flexibility, such that when subjected to developmental, biotic, or abiotic stimuli it can be rapidly remodeled in response. Genes encoding enzymes capable of synthesizing or hydrolyzing components of the plant cell wall show differential expression when subjected to different stresses, suggesting they may facilitate stress tolerance through changes in cell wall composition. In this review we summarize recent genetic and transcriptomic data from the literature supporting a role for specific cell wall-related genes in stress responses, in both dicot and monocot systems. These studies highlight that the molecular signatures of cell wall modification are often complex and dynamic, with multiple genes appearing to respond to a given stimulus. Despite this, comparisons between publically available datasets indicate that in many instances cell wall-related genes respond similarly to different pathogens and abiotic stresses, even across the monocot-dicot boundary. We propose that the emerging picture of cell wall remodeling during stress is one that utilizes a common toolkit of cell wall-related genes, multiple modifications to cell wall structure, and a defined set of stress-responsive transcription factors that regulate them.

For long time, studies on ectomycorrhiza (ECM) have been limited by inefficient expression of fluorescent proteins (FPs) in the fungal partner. To convert this situation, we have evaluated the basic requirements of FP expression in the model ECM homobasidiomycete Laccaria bicolor and established eGFP and mCherry as functional FP markers. Comparison of intron-containing and intronless FP-expression cassettes confirmed that intron-processing is indispensable for efficient FP expression in Laccaria . Nuclear FP localization was obtained via in-frame fusion of FPs between the intron-containing genomic gene sequences of Laccaria histone H2B, while cytosolic FP expression was produced by incorporating the intron-containing 5′ fragment of the glyceraldehyde-3-phosphate dehydrogenase encoding gene. In addition, we have characterized the consensus Kozak sequence of strongly expressed genes in Laccaria and demonstrated its boosting effect on transgene mRNA accumulation. Based on these results, an Agrobacterium -mediated transformation compatible plasmid set was designed for easy use of FPs in Laccaria . The four cloning plasmids presented here allow fast and highly flexible construction of C-terminal in-frame fusions between the sequences of interest and the two FPs, expressed either from the endogenous gene promoter, allowing thus evaluation of the native regulation modes of the gene under study, or alternatively, from the constitutive Agaricus bisporus gpdII promoter for enhanced cellular protein localization assays. The molecular tools described here for cell-biological studies in Laccaria can also be exploited in studies of other biotrophic or saprotrophic basidiomycete species susceptible to genetic transformation.

Proanthocyanidins (PAs) are polymeric phenolic compounds found in plants and used in many industrial applications. Despite strong evidence of herbivore and pathogen resistance-related properties of PAs, their in planta function is not fully understood. Determining the location and dynamics of PAs in plant tissues and cellular compartments is crucial to understand their mode of action. Such an approach requires microscopic localization with fluorescent dyes that specifically bind to PAs. Such dyes have hitherto been lacking. Here, we show that 4-dimethylaminocinnamaldehyde (DMACA) can be used as a PA-specific fluorescent dye that allows localization of PAs at high resolution in cell walls and inside cells using confocal microscopy, revealing features of previously unreported wall-bound PAs. We demonstrate several novel usages of DMACA as a fluorophore by taking advantage of its double staining compatibility with other fluorescent dyes. We illustrate the use of the dye alone and its co-localization with cell wall polymers in different Populus root tissues. The easy-to-use fluorescent staining method, together with its high photostability and compatibility with other fluorogenic dyes, makes DMACA a valuable tool for uncovering the biological function of PAs at a cellular level in plant tissues. DMACA can also be used in other plant tissues than roots, however care needs to be taken when tissues contain compounds that autofluoresce in the red spectral region which can be confounded with the PA-specific DMACA signal.

In plants, cell walls are one of the first lines of defence for protecting cells from successful invasion by fungal pathogens and are a major factor in basal host resistance. For the plant cell to block penetration attempts, it must adapt its cell wall to withstand the physical and chemical forces applied by the fungus. Papillae that have been effective in preventing penetration by pathogens are traditionally believed to contain callose as the main polysaccharide component. Here, we have re‐examined the composition of papillae of barley (Hordeum vulgare) attacked by the powdery mildew fungus Blumeria graminis f. sp. hordei (Bgh) using a range of antibodies and carbohydrate‐binding modules that are targeted to cell wall polysaccharides. The data show that barley papillae induced during infection with Bgh contain, in addition to callose, significant concentrations of cellulose and arabinoxylan. Higher concentrations of callose, arabinoxylan and cellulose are found in effective papillae, compared with ineffective papillae. The papillae have a layered structure, with the inner core consisting of callose and arabinoxylan and the outer layer containing arabinoxylan and cellulose. The association of arabinoxylan and cellulose with penetration resistance suggests new targets for the improvement of papilla composition and enhanced disease resistance.

Automated epileptic seizure detection from ectroencephalogram (EEG) signals has attracted significant attention in the recent health informatics field. The serious brain condition known as epilepsy, which is characterized by recurrent seizures, is typically described as a sudden change in behavior caused by a momentary shift in the excessive electrical discharges in a group of brain cells, and EEG signal is primarily used in most cases to identify seizure to revitalize the close loop brain. The development of various deep learning (DL) algorithms for epileptic seizure diagnosis has been driven by the EEG's non-invasiveness and capacity to provide repetitive patterns of seizure-related electrophysiological information. Existing DL models, especially in clinical contexts where irregular and unordered structures of physiological recordings make it difficult to think of them as a matrix; this has been a key disadvantage to producing a consistent and appropriate diagnosis outcome due to EEG's low amplitude and nonstationary nature. Graph neural networks have drawn significant improvement by exploiting implicit information that is present in a brain anatomical system, whereas inter-acting nodes are connected by edges whose weights can be determined by either temporal associations or anatomical connections. Considering all these aspects, a novel hybrid framework is proposed for epileptic seizure detection by combined with a sequential graph convolutional network (SGCN) and deep recurrent neural network (DeepRNN). Here, DepRNN is developed by fusing a gated recurrent unit (GRU) with a traditional RNN; its key benefit is that it solves the vanishing gradient problem and achieve this hybrid framework greater sophistication. The line length feature, auto-covariance, auto-correlation, and periodogram are applied as a feature from the raw EEG signal and then grouped the resulting matrix into time-frequency domain as inputs for the SGCN to use for seizure classification. This model extracts both spatial and temporal information, resulting in improved accuracy, precision, and recall for seizure detection. Extensive experiments conducted on the CHB-MIT and TUH datasets showed that the SGCN-DeepRNN model outperforms other deep learning models for seizure detection, achieving an accuracy of 99.007%, with high sensitivity and specificity.

Following cell entry, the RNA genome of HIV-1 is reverse transcribed into double-stranded DNA that ultimately integrates into the host-cell genome to establish the provirus. These early phases of infection are notably vulnerable to suppression by a collection of cellular antiviral effectors, called restriction or resistance factors. The host antiviral protein APOBEC3G (A3G) antagonizes the early steps of HIV-1 infection through the combined effects of inhibiting viral cDNA production and cytidine-to-uridine-driven hypermutation of this cDNA. In seeking to address the underlying molecular mechanism for inhibited cDNA synthesis, we developed a deep sequencing strategy to characterize nascent reverse transcription products and their precise 3′-termini in HIV-1 infected T cells. Our results demonstrate site- and sequence-independent interference with reverse transcription, which requires the specific interaction of A3G with reverse transcriptase itself. This approach also established, contrary to current ideas, that cellular uracil base excision repair (UBER) enzymes target and cleave A3G-edited uridine-containing viral cDNA. Together, these findings yield further insights into the regulatory interplay between reverse transcriptase, A3G and cellular DNA repair machinery, and identify the suppression of HIV-1 reverse transcriptase by a directly interacting host protein as a new cell-mediated antiviral mechanism. APOBEC3G is shown to induce a potent, non-site-specific interference with reverse transcription through direct interaction with HIV-1 reverse transcriptase, and host DNA repair machinery is shown to cleave HIV-1 cDNA.

Cell walls and cellular turgor pressure shape and suspend the bodies of all vascular plants. In response to attack by fungal and oomycete pathogens, which usually breach their host’s cell walls by mechanical force or by secreting lytic enzymes, plants often form local cell wall appositions (papillae) as an important first line of defence. The involvement of cell wall biosynthetic enzymes in the formation of these papillae is still poorly understood, especially in cereal crops. To investigate the role in plant defence of a candidate gene from barley (Hordeum vulgare) encoding cellulose synthase-like D2 (HvCslD2), we generated transgenic barley plants in which HvCslD2 was silenced through RNA interference (RNAi). The transgenic plants showed no growth defects but their papillae were more successfully penetrated by host-adapted, virulent as well as avirulent nonhost isolates of the powdery mildew fungus Blumeria graminis. Papilla penetration was associated with lower contents of cellulose in epidermal cell walls and increased digestion by fungal cell wall degrading enzymes. The results suggest that HvCslD2-mediated cell wall changes in the epidermal layer represent an important defence reaction both for nonhost and for quantitative host resistance against nonadapted wheat and host-adapted barley powdery mildew pathogens, respectively.

The recent characterization of the polysaccharide composition of papillae deposited at the barley cell wall during infection by the powdery mildew pathogen, Blumeria graminis f. sp. hordei (Bgh), has provided new targets for the generation of enhanced disease resistance. The role of callose in papilla-based penetration resistance of crop species is largely unknown because the genes involved in the observed callose accumulation have not been identified unequivocally. We have employed both comparative and functional genomics approaches to identify the functional orthologue of AtGsl5 in the barley genome. HvGsl6 (the barley glucan synthase-like gene), which has the highest sequence identity to AtGsl5, is the only Bgh-induced gene among the HvGsls examined in this study. Through double-stranded RNA interference (dsRNAi)-mediated silencing of HvGsl6, we have shown that the down-regulation of HvGsl6 is associated with a lower accumulation of papillary and wound callose and a higher susceptibility to penetration of the papillae by Bgh, compared with control lines. The results indicate that the HvGsl6 gene is a functional orthologue of AtGsl5 and is involved in papillary callose accumulation in barley. The increased susceptibility of HvGsl6 dsRNAi transgenic lines to infection indicates that callose positively contributes to the barley fungal penetration resistance mechanism.

West Nile virus is an arbovirus primarily spread by mosquitoes, which are the principal carriers and belong to the Flaviviridae category. This widespread disease lacks specific treatments despite its potential lethality, urgently demanding novel pharmaceutical research and development aims to prevent severe or long-term complications and improve overall outcomes. Pandemic awareness, increasing global incidence, fatal illness effects, expenses associated with outbreaks, reducing suffering, and other broader implications highlight the study’s wider significance. Drug design as a novel treatment approach to reduce the risk of resistance to the virus resulting from overuse of broad-spectrum antiviral therapies for unrelated viral diseases has been evaluated using computational techniques. Initially, molecular docking targeted the envelope glycoprotein of the WNV, utilizing a set of 5375 phytochemicals found in the IMPPAT database. Their binding affinities were −7.464, −5.802, −5.617, and −4.92, kcal/mol for CID: 359 (Phloroglucinol), 9064 (Cianidanol), 25310 (L-Rhamnose), and 492405 (Favipiravir), respectively. The lead compounds and the control ligand both bind at the common active site of the macro-molecule, as evidenced by their interactions with the same amino acid residues at LEU281, ASN47, THR282, SER29, MET48, MET46, and MET45, correspondingly. In post-docking MM-GBSA the negative binding energy of the P-L complex for the compounds CIDs: 359, 9064, 25310, and 492405 (control) were −29.16, −33.45, −32.02, and −3.16 kcal/mol, correspondingly. The selected compounds are secure and efficient since they demonstrate excellent toxicological and Pk characteristics. The compounds were further evaluated to confirm their stability and binding affinity to the target protein by molecular dynamics simulation (RMSD, RMSF, Rg, SASA, H-bond, P-L, and L-P contact). Following this, principal component analysis (PCA) and dynamic cross-correlation matrix (DCCM) studies were conducted using the MD trajectory data. The ligands evaluated in this study demonstrated considerable stability of the proteins’ binding site when complexed with CID: 9064 and CID: 25310, respectively, in the MD simulation, which also revealed a high negative binding free energy value, indicating a robust interaction between the target and lead compounds. The three principal components (PC1, PC2, PC3) for the lead compounds corresponding to CID: 9064 (40.37%, 23.02%, and 8.82%) and CID: 25310 (73.04%, 10.06%, and 3.77%), respectively, indicate that their complexes are more stable than the other L-P complexes. Consequently, both the compounds derived from the plants Tamarindus indica and Plantago ovate , respectively, may potentially impede the viral activity of the WNV envelope glycoprotein, indicating the possibility of these compounds as prospective phytochemical therapeutic candidates. This preclinical study can be used in further drug development processes, including in vivo studies and animal trials.

Background Amino-acid biostimulants have emerged as powerful alternatives to conventional inorganic nitrogen fertilisers, yet their potential in forestry species like radiata pine ( Pinus radiata ) remains largely unexplored. In this study, we reveal physiological mechanisms of enhanced growth of radiata pine seedlings that are achieved by substituting standard inorganic fertigation, either partially or entirely, with amino-acid-based biostimulants. Results Amino-acid fertigation notably increased shoot biomass, plant height, and root collar diameter. Critically, this approach reshaped the root fungal community, selectively enriching fungi with diverse ecological roles, including several taxa known for auxin production. These microbial shifts coincided with higher needle auxin, a plausible link that merits testing. Machine learning models further identified key fungal genera that strongly associated with plant biomass, reinforcing microbiome shifts as a contributing mechanism to enhanced growth. Additionally, amino-acid fertigation improved nitrogen assimilation, correlating positively with increased chlorophyll content and photosynthetic efficiency. Conclusions Our findings highlight that the transition from inorganic source to amino-acid biostimulants not only enhances plant growth and nitrogen use but also associated with a shift in the root mycobiome, including taxa often considered beneficial, thereby offering a sustainable pathway to nursery production of radiata pine.