Inhibitory effects and mechanisms of cinnamaldehyde against Fusarium oxysporum, a serious pathogen in potatoes.

BACKGROUND: Potatoes, a major economic crop, are significantly impacted by Fusarium dry rot, a prevalent postharvest disease. Despite the broad-spectrum antimicrobial properties of cinnamaldehyde, a naturally-derived plant substance, its efficacy against the causal pathogen of potato dry rot (Fusarium oxysporum) and the underlying mechanisms have not been extensively studied. RESULTS: Our study demonstrates that cinnamaldehyde effectively inhibits the growth of Fusarium oxysporum, the pathogen responsible for potato dry rot, and increases its sensitivity to environmental stress factors such as extreme temperatures and high salt stress. Treatment with cinnamaldehyde results in altered fungal mycelium morphology, compromised cell wall stability, and disrupted cell membrane integrity, thereby reducing spore viability. Specifically, it interferes with the cell membrane and cell wall structures of the fungus, potentially disrupting fungal growth by modulating signaling pathways involved in cell wall maintenance, chitin metabolism, and GPI-anchored protein function. Notably, we show that cinnamaldehyde induces a form of regulated cell death in F. oxysporum, which is characterized not as typical apoptosis, as evidenced by Annexin V negative staining. However, the specific cell death type and underlying mechanism still needed to be further explored. CONCLUSION: Cinnamaldehyde, an environmentally friendly plant-based active compound, exhibits strong inhibitory effects on F. oxysporum, indicating its potential use in the prevention and control strategies for potato dry rot. This research contributes to the understanding of novel antifungal mechanisms and offers promising insights into eco-friendly alternatives for managing this economically significant postharvest disease. © 2024 Society of Chemical Industry.

A comprehensive review of TGA transcription factors in plant growth, stress responses, and beyond.

TGA transcription factors (TFs), belonging to the D clade of the basic region leucine zipper (bZIP) family, exhibit a specific ability to recognize and bind to regulatory elements with TGACG as the core recognition sequence, enabling the regulation of target gene expression and participation in various biological regulatory processes. In plant growth and development, TGA TFs influence organ traits and phenotypes, including initial root length and flowering time. They also play a vital role in responding to abiotic stresses like salt, drought, and cadmium exposure. Additionally, TGA TFs are involved in defending against potential biological stresses, such as fungal bacterial diseases and nematodes. Notably, TGA TFs are sensitive to the oxidative-reductive state within plants and participate in pathways that aid in the elimination of reactive oxygen species (ROS) generated during stressful conditions. TGA TFs also participate in multiple phytohormonal signaling pathways (ABA, SA, etc.). This review thoroughly examines the roles of TGA TFs in plant growth, development, and stress response. It also provides detailed insights into the mechanisms underlying their involvement in physiological and pathological processes, and their participation in plant hormone signaling. This multifaceted exploration distinguishes this review from others, offering a comprehensive understanding of TGA TFs.

Advances in Brain Tumor Therapy Based on the Magnetic Nanoparticles.

Brain tumors, including primary gliomas and brain metastases, are one of the deadliest tumors because effective macromolecular antitumor drugs cannot easily penetrate the blood-brain barrier (BBB) and blood-brain tumor barrier (BTB). Magnetic nanoparticles (MNPs) are considered the most suitable nanocarriers for the delivery of brain tumor drugs because of their unique properties compared to other nanoparticles. Numerous preclinical and clinical studies have demonstrated the potential of these nanoparticles in magnetic targeting, nuclear magnetic resonance, magnetic thermal therapy, and ultrasonic hyperthermia. To further develop and optimize MNPs for the diagnosis and treatment of brain tumors, we attempt to outline recent advances in the use of MNPs to deliver drugs, with a particular focus on their efficacy in the delivery of anti-brain tumor drugs based on magnetic targeting and low-intensity focused ultrasound, magnetic resonance imaging for surgical real-time guidance, and magnetothermal and ultrasonic hyperthermia therapy. Furthermore, we summarize recent findings on the clinical application of MNPs and the research limitations that need to be addressed in clinical translation.

Anti-Oomycete Effect and Mechanism of Salicylic Acid on Phytophthora infestans.

Pathogenic oomycetes infect a wide variety of organisms, including plants, animals, and humans, and cause massive economic losses in global agriculture, aquaculture, and human health. Salicylic acid (SA), an endogenous phytohormone, is regarded as an inducer of plant immunity. Here, the potato late blight pathogen Phytophthora infestans was used as a model system to uncover the inhibitory mechanisms of SA on pathogenic oomycetes. In this research, SA significantly inhibited the mycelial growth, sporulation, sporangium germination, and virulence of P. infestans. Inhibition was closely related to enhanced autophagy, suppression of translation initiation, and ribosomal biogenesis in P. infestans, as shown by multiomics analysis (transcriptomics, proteomics, and phosphorylated proteomics). Monodansylcadaverine (MDC) staining and Western blotting analysis showed that SA promoted autophagy in P. infestans by probably targeting the TOR signaling pathway. These observations suggest that SA has the potential to control late blight caused by P. infestans.

Endophytic Bacillus subtilis H17-16 effectively inhibits Phytophthora infestans, the pathogen of potato late blight, and its potential application.

BACKGROUND: As a highly prevalent epidemic disease of potato, late blight caused by Phytophthora infestans poses a serious threat to potato yield and quality. At present, chemical fungicides are mainly used to control potato late blight, but long-term overuse of chemical fungicides may lead to environmental pollution and human health threats. Endophytes, natural resources for plant diseases control, can promote plant growth, enhance plant resistance, and secrete antifungal substances. Therefore, there is an urgent need to find some beneficial endophytes to control potato late blight. RESULTS: We isolated a strain of Bacillus subtilis H17-16 from potato healthy roots. It can significantly inhibit mycelial growth, sporangia germination and the pathogenicity of Phytophthora infestans, induce the resistance of potato to late blight, and promote potato growth. In addition, H17-16 has the ability to produce protease, volatile compounds (VOCs) and form biofilms. After H17-16 treatment, most of the genes involved in metabolism, virulence and drug resistance of Phytophthora infestans were down-regulated significantly, and the genes related to ribosome biogenesis were mainly up-regulated. Moreover, field and postharvest application of H17-16 can effectively reduce the occurrence of potato late blight, and the combination of H17-16 with chitosan or chemical fungicides had a better effect than single H17-16. CONCLUSION: Our results reveal that Bacillus subtilis H17-16 has great potential as a natural fungicide for controlling potato late blight, laying a theoretical basis for its development as a biological control agent. © 2023 Society of Chemical Industry.

Isolation and Screening of Antagonistic Endophytes against Phytophthora infestans and Preliminary Exploration on Anti-oomycete Mechanism of Bacillus velezensis 6-5.

Phytophthora infestans, the notorious pathogen of potato late blight, leads to a severe decline in potato yields and even harvest failure. We isolated 201 endophytic isolates from healthy root tissues of potatoes, among which 41 showed strong antagonistic activity against P. infestans. Further, the tolerance to stress and the potential application against potato late blight of these antagonistic isolates were tested. Most of them were extremely tolerant to stresses such as acid-alkali, temperature, UV, salt, and heavy metal stress. However, some antagonistic isolates with excellent stress tolerance might be pathogenic to potatoes. Combining the screening results, a total of 14 endophytes had excellent comprehensive performance in all the tests. In this paper, the endophyte 6-5 was selected among them for the preliminary exploration of the anti-oomycete mechanism. Analysis of the 16S rDNA sequence revealed that 6-5 had a high homology to the corresponding sequence of Bacillus velezensis (99.72%) from the NCBI database. Endophyte 6-5 significantly inhibited the mycelial growth of P. infestans, with an inhibition rate of over 90% in vitro assays, and deformed the hyphal phenotype of P. infestans. In addition, endophyte 6-5 could secrete protease and cellulase, and produce antagonistic substances with high thermal stability, which might be helpful to its antagonistic activity against P. infestans. Furthermore, it was demonstrated that 6-5 had the ability to improve the resistance of potato tubers to late blight. In short, our study described the process of isolating and screening endophytes with antagonistic activity against P. infestans from potato roots, and further explored the potential of biocontrol candidate strain 6-5 in potato late blight control.

Integrative mRNA and microRNA Analysis Exploring the Inducing Effect and Mechanism of Diallyl Trisulfide (DATS) on Potato against Late Blight.

Potato late blight, caused by Phytophthora infestans, leads to a significant reduction in the yield and value of potato. Biocontrol displays great potential in the suppression of plant diseases. Diallyl trisulfide (DATS) is a well-known natural compound for biocontrol, although there is little information about it against potato late blight. In this study, DATS was found to be able to inhibit the hyphae growth of P. infestans, reduce its pathogenicity on detached potato leaves and tubers, and induce the overall resistance of potato tubers. DATS significantly increases catalase (CAT) activity of potato tubers, and it does not affect the levels of peroxidase (POD), superoxide dismutase (SOD), and malondialdehyde (MDA). The transcriptome datasets show that totals of 607 and 60 significantly differentially expressed genes (DEGs) and miRNAs (DEMs) are detected. Twenty-one negatively regulated miRNA-mRNA interaction pairs are observed in the co-expression regulatory network, which are mainly enriched in metabolic pathways, biosynthesis of secondary metabolites, and starch and sucrose metabolism based on the KEGG pathway. Our observations provide new insight into the role of DATS in biocontrol of potato late blight.

Intrachromosomal Looping and Histone K27 Methylation Coordinately Regulates the lncRNA H19-Fetal Mitogen IGF2 Imprinting Cluster in the Decidual Microenvironment of Early Pregnancy.

Recurrent spontaneous abortion (RSA) is a highly heterogeneous complication of pregnancy with the underlying mechanisms remaining uncharacterized. Dysregulated decidualization is a critical contributor to the phenotypic alterations related to pregnancy complications. To understand the molecular factors underlying RSA, we explored the role of longnoncoding RNAs (lncRNAs) in the decidual microenvironment where the crosstalk at the fetal-maternal interface occurs. By exploring RNA-seq data from RSA patients, we identified H19, a noncoding RNA that exhibits maternal monoallelic expression, as one of the most upregulated lncRNAs associated with RSA. The paternally expressed fetal mitogen IGF2, which is reciprocally coregulated with H19 within the same imprinting cluster, was also upregulated. Notably, both genes underwent loss of imprinting, as H19 and IGF2 were actively transcribed from both parental alleles in some decidual tissues. This loss of imprinting in decidual tissues was associated with the loss of the H3K27m3 repressive histone marker in the IGF2 promoter, CpG hypomethylation at the central CTCF binding site in the imprinting control center (ICR), and the loss of CTCF-mediated intrachromosomal looping. These data suggest that dysregulation of the H19/IGF2 imprinting pathway may be an important epigenetic factor in the decidual microenvironment related to poor decidualization.

Observation and analysis of the efficacy of dexamethasone in combination with anti-infectious treatment on the pediatric refractory purulent meningitis.

To analyze the pathogenic bacteria, feature of drug resistance and the efficacy of dexamethasone as the auxiliary medication in pediatric refractory purulent meningitis (PM). The 190 refractory PM child patients were selected for the culture of pathogenic bacteria and analysis of drug resistance. In total, 190 pathogenic bacteria were detected, consisting of gram-positive bacteria (77.37%). Of the gram-positive bacteria, the resistance rate of patients with staphylococcus epidermidis, streptococcus pneumoniae or Staphylococcus haemolyticus to levofloxacin was 100%, while in gram-negative bacteria, the resistance rate of patients with klebsiella pneumoniae to gentamycin was 100%. In the observation group, patients had a higher effectiveness rate. Besides, patients in the observation group recovered rapidly from the fever and anomalies in cerebral spine fluid and peripheral white blood cells, and the inflammation was greatly improved. However, difference in the incidence rates of adverse reactions of patients between two groups showed no statistical significance. Pediatric refractory PM involves the pathogenic bacteria, mainly including staphylococcus epidermidis and streptococcus pneumoniae, showing a high resistance to levofloxacin, while the auxiliary medication of dexamethasone can improve the efficacy, and inhibit the inflammation.