Urolithin A promotes atherosclerotic plaque stability by limiting inflammation and hypercholesteremia in Apolipoprotein E-deficient mice.

Urolithin A (UroA), a dietary phytochemical, is produced by gut bacteria from fruits rich in natural polyphenols ellagitannins (ETs). The efficiency of ETs metabolism to UroA in humans depends on gut microbiota. UroA has shown a variety of pharmacological activities. In this study we investigated the effects of UroA on atherosclerotic lesion development and stability. Apolipoprotein E-deficient (ApoE-/-) mice were fed a high-fat and high-cholesterol diet for 3 months to establish atherosclerosis model. Meanwhile the mice were administered UroA (50 mg·kg-1·d-1, i.g.). We showed that UroA administration significantly decreased diet-induced atherosclerotic lesions in brachiocephalic arteries, macrophage content in plaques, expression of endothelial adhesion molecules, intraplaque hemorrhage and size of necrotic core, while increased the expression of smooth muscle actin and the thickness of fibrous cap, implying features of plaque stabilization. The underlying mechanisms were elucidated using TNF-α-stimulated human endothelial cells. Pretreatment with UroA (10, 25, 50 µM) dose-dependently inhibited TNF-α-induced endothelial cell activation and monocyte adhesion. However, the anti-inflammatory effects of UroA in TNF-α-stimulated human umbilical vein endothelial cells (HUVECs) were independent of NF-κB p65 pathway. We conducted RNA-sequencing profiling analysis to identify the differential expression of genes (DEGs) associated with vascular function, inflammatory responses, cell adhesion and thrombosis in UroA-pretreated HUVECs. Human disease enrichment analysis revealed that the DEGs were significantly correlated with cardiovascular diseases. We demonstrated that UroA pretreatment mitigated endothelial inflammation by promoting NO production and decreasing YAP/TAZ protein expression and TEAD transcriptional activity in TNF-α-stimulated HUVECs. On the other hand, we found that UroA administration modulated the transcription and cleavage of lipogenic transcription factors SREBP1/2 in the liver to ameliorate cholesterol metabolism in ApoE-/- mice. This study provides an experimental basis for new dietary therapeutic option to prevent atherosclerosis.

Up-regulation of microglial chemokine CXCL12 in anterior cingulate cortex mediates neuropathic pain in diabetic mice.

Diabetic patients frequently experience neuropathic pain, which currently lacks effective treatments. The mechanisms underlying diabetic neuropathic pain remain unclear. The anterior cingulate cortex (ACC) is well-known to participate in the processing and transformation of pain information derived from internal and external sensory stimulation. Accumulating evidence shows that dysfunction of microglia in the central nervous system contributes to many diseases, including chronic pain and neurodegenerative diseases. In this study, we investigated the role of microglial chemokine CXCL12 and its neuronal receptor CXCR4 in diabetic pain development in a mouse diabetic model established by injection of streptozotocin (STZ). Pain sensitization was assessed by the left hindpaw pain threshold in von Frey filament test. Iba1+ microglia in ACC was examined using combined immunohistochemistry and three-dimensional reconstruction. The activity of glutamatergic neurons in ACC (ACCGlu) was detected by whole-cell recording in ACC slices from STZ mice, in vivo multi-tetrode electrophysiological and fiber photometric recordings. We showed that microglia in ACC was significantly activated and microglial CXCL12 expression was up-regulated at the 7-th week post-injection, resulting in hyperactivity of ACCGlu and pain sensitization. Pharmacological inhibition of microglia or blockade of CXCR4 in ACC by infusing minocycline or AMD3100 significantly alleviated diabetic pain through preventing ACCGlu hyperactivity in STZ mice. In addition, inhibition of microglia by infusing minocycline markedly decreased STZ-induced upregulation of microglial CXCL12. Together, this study demonstrated that microglia-mediated ACCGlu hyperactivity drives the development of diabetic pain via the CXCL12/CXCR4 signaling, thus revealing viable therapeutic targets for the treatment of diabetic pain.

A novel mouse model of diabetes, atherosclerosis and fatty liver disease using an AAV8-PCSK9-D377Y injection and dietary manipulation in db/db mice.

Preclinical mouse models of cardiometabolic diseases are crucial to study the pathological mechanisms of cardiometabolic diseases and to explore potential new therapeutic agents. Using double-knockouts in the background of ApoE-/- or Ldlr-/- mice requires an extensive amount of breeding and is costly. A significant breakthrough in atherosclerosis research is the use of AAV8-PCSK9-D377Y (a gain-of-function mutant of PCSK9 which promotes LDLR degradation) injection which can induce hyperlipidemia, increased endothelial stiffness, vascular calcification, aneurysm, and atherosclerotic plaque development in normal C57BL/6J mice. The purpose of this study was to assess the possibility that the injection of AAV8-PCSK9 vectors in db/db mice (a well-established animal model of type 2 diabetes mellitus) produces a novel mouse model of diabetes, atherosclerosis and fatty liver disease to study the pathomechanisms of cardiometabolic disease and its complications. Db/db mice were injected with AAV8-PCSK9-D377Y (AAV8-PCSK9 for simplicity) or AAV8-control and fed with high-cholesterol diets for 8 weeks. Levels of total cholesterol (TC) and triglyceride (TG) were significantly elevated in AAV8-PCSK9-injected mice compared to the controls. AAV8-PCSK9 injection led to increased serum level of PCSK9, serious liver steatosis, hypercholesterolemia and atherosclerotic plaque as determined by aortic arch/roots histopathological staining, with Oil Red O, Masson-trichrome and hematoxylin-eosin staining. RNA sequencing and bioinformatics were used to assess the global gene expression in liver tissues. We conclude that AAV8-PCSK9 injection in db/db mice is a promising and time-efficient approach to induce diabetic atherosclerosis with fatty liver. This mouse model can be a new one to investigate the etiology and therapeutics of atherosclerosis with diabetes and fatty liver beyond the traditional model established in ApoE-/- mice or LDLR-/- mice receiving streptozotocin (STZ) injection.

Pharmacological inhibition of IRAK1 and IRAK4 prevents endothelial inflammation and atherosclerosis in ApoE-/- mice.

Inflammation associated endothelial dysfunction represents a pivotal contributor to atherosclerosis. Increasingly, evidence has demonstrated that interleukin 1 receptor (IL1-R) / toll-like receptor (TLR) signaling participates in the development of atherosclerosis. Recent large-scale clinical trials have supported the therapeutic potential of anti-inflammatory therapies targeting IL-1ß and IL-6 in reducing atherosclerosis. The present study examined the pharmacological effects of IL-1R-associated kinase 1 and 4 inhibitors (IRAK1/4i) in regulating inflammation of the endothelium and atherosclerosis. We demonstrate that dual pharmacological inhibition of IRAK1 and IRAK4 by an IRAK1/4i is more effective against LPS induced endothelial inflammation, compared with IRAK1 inhibitor or IRAK4 inhibitor monotherapy. IRAK1/4i showed little endothelial cell toxicity at concentrations from 1 µM up to 10 µM. Inhibition of IRAK1/4 reduced endothelial activation induced by LPS in vitro as evidenced by attenuated monocyte adhesion to the endothelium. Mechanistically, blockade of IRAK1/4 ameliorated the transcriptional activity of NF-κB. To assess the pharmacological effects of IRAK1/4i on atherosclerosis in vivo, ApoE-/- mice were orally administered IRAK1/4i (20 mg/kg/d) for 8 weeks. We show that IRAK1/4i reduced atherosclerotic lesion size in the aortic sinus and increased hepatic LDLR protein levels as well as lowered LDL-C level, without affecting other lipid parameters or glucose tolerance. Taken together, our findings demonstrate that dual pharmacological inhibition of IRAK1 and IRAK4 attenuates endothelial inflammation, lowers LDL-C levels and reduces atherosclerosis. Our study reinforces the evolving standing of anti-inflammatory approaches in cardiovascular therapeutics.

Comparative Proteomic Analysis of Liver Tissues and Serum in db/db Mice.

BACKGROUND AND AIMS: Non-alcoholic fatty liver disease (NAFLD) affects one-quarter of individuals worldwide. Liver biopsy, as the current reliable method for NAFLD evaluation, causes low patient acceptance because of the nature of invasive sampling. Therefore, sensitive non-invasive serum biomarkers are urgently needed. RESULTS: The serum gene ontology (GO) classification and Kyoto encyclopedia of genes and genomes (KEGG) analysis revealed the DEPs enriched in pathways including JAK-STAT and FoxO. GO analysis indicated that serum DEPs were mainly involved in the cellular process, metabolic process, response to stimulus, and biological regulation. Hepatic proteomic KEGG analysis revealed the DEPs were mainly enriched in the PPAR signaling pathway, retinol metabolism, glycine, serine, and threonine metabolism, fatty acid elongation, biosynthesis of unsaturated fatty acids, glutathione metabolism, and steroid hormone biosynthesis. GO analysis revealed that DEPs predominantly participated in cellular, biological regulation, multicellular organismal, localization, signaling, multi-organism, and immune system processes. Protein-protein interaction (PPI) implied diverse clusters of the DEPs. Besides, the paralleled changes of the common upregulated and downregulated DEPs existed in both the liver and serum were validated in the mRNA expression of NRP1, MUP3, SERPINA1E, ALPL, and ALDOB as observed in our proteomic screening. METHODS: We conducted hepatic and serum proteomic analysis based on the leptin-receptor-deficient mouse (db/db), a well-established diabetic mouse model with overt obesity and NAFLD. The results show differentially expressed proteins (DEPs) in hepatic and serum proteomic analysis. A parallel reaction monitor (PRM) confirmed the authenticity of the selected DEPs. CONCLUSION: These results are supposed to offer sensitive non-invasive serum biomarkers for diabetes and NAFLD.

Resistance against Ralstonia solanacearum in tomato depends on the methionine cycle and the γ-aminobutyric acid metabolic pathway.

Bacterial wilt caused by Ralstonia solanacearum is a complex and destructive disease that affects over 200 plant species. To investigate the interaction of R. solanacearum and its tomato (Solanum lycopersicum) plant host, a comparative proteomic analysis was conducted in tomato stems inoculated with highly and mildly aggressive R. solanacearum isolates (RsH and RsM, respectively). The results indicated a significant alteration of the methionine cycle (MTC) and downregulation of γ-aminobutyric acid (GABA) biosynthesis. Furthermore, transcriptome profiling of two key tissues (stem and root) at three stages (0, 3 and 5 days post-inoculation) with RsH in resistant and susceptible tomato plants is presented. Transcript profiles of MTC and GABA pathways were analyzed. Subsequently, the MTC-associated genes SAMS2, SAHH1 and MS1 and the GABA biosynthesis-related genes GAD2 and SSADH1 were knocked-down by virus-induced gene silencing and the plants' defense responses upon infection with R. solanacearum RsM and RsH were analyzed. These results showed that silencing of SAHH1, MS1 and GAD2 in tomato leads to decreased resistance against R. solanacearum. In summary, the infection assays, proteomic and transcriptomic data described in this study indicate that both MTC and GABA biosynthesis play an important role in pathogenic interaction between R. solanacearum and tomato plants.

Fine Mapping Identifies SmFAS Encoding an Anthocyanidin Synthase as a Putative Candidate Gene for Flower Purple Color in Solanum melongena L.

Anthocyanins are the main pigments in flowers and fruits. These pigments are responsible for the red, red-purple, violet, and purple color in plants, and act as insect and animal attractants. In this study, phenotypic analysis of the purple flower color in eggplant indicated that the flower color is controlled by a single dominant gene, FAS. Using an F2 mapping population derived from a cross between purple-flowered 'Blacknite' and white-flowered 'Small Round', FlowerAnthocyanidin Synthase (FAS) was fine mapped to an approximately 165.6-kb region between InDel marker Indel8-11 and Cleaved Amplified Polymorphic Sequences (CAPS) marker Efc8-32 on Chromosome 8. On the basis of bioinformatic analysis, 29 genes were subsequently located in the FAS target region, among which were two potential Anthocyanidin Synthase (ANS) gene candidates. Allelic sequence comparison results showed that one ANS gene (Sme2.5_01638.1_g00003.1) was conserved in promoter and coding sequences without any nucleotide change between parents, whereas four single-nucleotide polymorphisms were detected in another ANS gene (Sme2.5_01638.1_g00005.1). Crucially, a single base pair deletion at site 438 resulted in premature termination of FAS, leading to the loss of anthocyanin accumulation. In addition, FAS displayed strong expression in purple flowers compared with white flowers and other tissues. Collectively, our results indicate that Sme2.5_01638.1_g00005.1 is a good candidate gene for FAS, which controls anthocyanidin synthase in eggplant flowers. The present study provides information for further potential facilitate genetic engineering for improvement of anthocyanin levels in plants.

Fortifying Horticultural Crops with Essential Amino Acids: A Review.

To feed the world's growing population, increasing the yield of crops is not the only important factor, improving crop quality is also important, and it presents a significant challenge. Among the important crops, horticultural crops (particularly fruits and vegetables) provide numerous health compounds, such as vitamins, antioxidants, and amino acids. Essential amino acids are those that cannot be produced by the organism and, therefore, must be obtained from diet, particularly from meat, eggs, and milk, as well as a variety of plants. Extensive efforts have been devoted to increasing the levels of essential amino acids in plants. Yet, these efforts have been met with very little success due to the limited genetic resources for plant breeding and because high essential amino acid content is generally accompanied by limited plant growth. With a deep understanding of the biosynthetic pathways of essential amino acids and their interactions with the regulatory networks in plants, it should be possible to use genetic engineering to improve the essential amino acid content of horticultural plants, rendering these plants more nutritionally favorable crops. In the present report, we describe the recent advances in the enhancement of essential amino acids in horticultural plants and possible future directions towards their bio-fortification.

ABA-induced CCCH tandem zinc finger protein OsC3H47 decreases ABA sensitivity and promotes drought tolerance in Oryza sativa.

Water deficit causes multiple negative impacts on plants, such as reactive oxygen species (ROS) accumulation, abscisic acid (ABA) induction, stomatal closure, and decreased photosynthesis. Here, we characterized OsC3H47, which belongs to CCCH zinc-finger families, as a drought-stress response gene. It can be strongly induced by NaCl, PEG, ABA, and drought conditions. Overexpression of OsC3H47 significantly enhanced tolerance to drought and salt stresses in rice seedlings, which indicates that OsC3H47 plays important roles in post-stress recovery. However, overexpression of OsC3H47 reduced the ABA sensitivity of rice seedlings. This suggests that OsC3H47 is a newly discovered gene that can control rice drought-stress response, and it may play an important role in ABA feedback and post-transcription processes.

Exploring the roles of basal transcription factor 3 in eukaryotic growth and development.

Basal transcription factor 3 (BTF3) has been reported to play a significant part in the transcriptional regulation linking with eukaryotes growth and development. Alteration in the BTF3 gene expression patterns or variation in their activities adds to the explanation of different signaling pathways and regulatory networks. Moreover, BTF3s often respond to numerous stresses, and subsequently they are involved in regulation of various mechanisms. BTF3 proteins also function through protein-protein contact, which can assist us to identify the multifaceted processes of signaling and transcriptional regulation controlled by BTF3 proteins. In this review, we discuss current advances made in starting to explore the roles of BTF3 transcription factors in eukaryotes especially in plant growth and development.

[Performance of wavelength modulation surface plasmon resonance biosensor].

Surface plasmon resonance (SPR) is a rapid, label-free, high-precision technique of biological sensing and analysis. The investigation on the characteristics of provides theoretical basis and instructions for the applications of SPR A Kretschmann-structure surface plasmon resonance (SPR) biosensor based on wavelength modulation was developed, and also its sensing performances in the bulk solution was investigated. Measurements with different concentrations of bulk ethanol and ethylene glycol solutions show that the resonant wavelength shows a low sensitivity, but a higher linear response to the change in refractive index (RI), when RI is relatively smaller. With increasing refractive index , the sensitivity of resonance wavelength to changes in the refractive index increases. In the refractive index range of 1. 407 0-1. 430 RIU, sensitivity reaches to 11 487 nm RIU-1. The sensor resonance wavelength stability is 0. 213 8 nm, and the minimum resolution of refractive index approaches to 10-6 RIU. The advantages of the surface plasmon resonance sensor developed here results in simple operation, high sensitivity, wide detection range, low resolution, makes it an important candidate in chemical and biological sensing.

[Spectra modulated surface plasmon resonance sensor based on side polished multi-mode optical fiber].

Surface plasmon resonance, which utilizes the resonance of optical evanescent wave with the metal surface plasmon wave, has been developed into a high sensitivity, rapid, label-less measurement method for chemical and biological analysis. In order to improve the spectral sensitivity in refractive index for a side polished fiber surface plasmon resonance sensor, the whole cladding layer and part of core of a multimode fiber was polished off. Additionally, an extra chrome layer with relatively high refractive index was coated on the polished zone before a gold film. The results showed that the sensor can measure the refractive index range from 1.333 to 1. 431 RIU, with the average spectral sensitivity of 4.11 x 10(3) nm RIU(-1), which is better than the reported results. Especially, in the refractive index range of 1. 417 1. 431 RIU, the sensitivity reaches to 1.09 x 10(4) nm RIU(-1). The minimum resolution of approximately 3.6 x 10(-5) RIU was estimated by a combination analysis with the sensor sensitivity and stability. The superiorities possessed by the proposed sensor in high sensitivity, wide detection range, small size and good stability and reproducibility, etc., make it a good candidate for food testing, environmental monitoring, biomedical testing and other related fields.

TRIM56 protects against nonalcoholic fatty liver disease by promoting the degradation of fatty acid synthase.

Nonalcoholic fatty liver disease (NAFLD) encompasses a disease continuum from simple steatosis to nonalcoholic steatohepatitis (NASH). However, there are currently no approved pharmacotherapies for NAFLD, although several drugs are in advanced stages of clinical development. Because of the complex pathophysiology and heterogeneity of NAFLD, the identification of potential therapeutic targets is clinically important. Here, we demonstrated that tripartite motif 56 (TRIM56) protein abundance was markedly downregulated in the livers of individuals with NAFLD and of mice fed a high-fat diet. Hepatocyte-specific ablation of TRIM56 exacerbated the progression of NAFLD, while hepatic TRIM56 overexpression suppressed it. Integrative analyses of interactome and transcriptome profiling revealed a pivotal role of TRIM56 in lipid metabolism and identified the lipogenesis factor fatty acid synthase (FASN) as a direct binding partner of TRIM56. TRIM56 directly interacted with FASN and triggered its K48-linked ubiquitination-dependent degradation. Finally, using artificial intelligence-based virtual screening, we discovered an orally bioavailable small-molecule inhibitor of FASN (named FASstatin) that potentiates TRIM56-mediated FASN ubiquitination. Therapeutic administration of FASstatin improved NAFLD and NASH pathologies in mice with an optimal safety, tolerability, and pharmacokinetics profile. Our findings provide proof of concept that targeting the TRIM56/FASN axis in hepatocytes may offer potential therapeutic avenues to treat NAFLD.

Ultrasensitive label free electrical detection of insulin in neat blood serum.

Electrical assays potentially offer a highly sensitive, cheap, portable, automated, and multiplexed means of protein biomarker detection, characteristics with an ability to underpin both disease stratification and the development of point of care diagnostics. Most conveniently applied in a reagent free manner, all sensitive assays such as these suffer, however, from profound problems when applied in complex fluids such as blood serum. We report herein, the development, and clinical application, of a highly sensitive and selective electrical insulin biosensor based on a chemisorbed zwittorionic polymer support and a novel reagentless sensing technique based on phase monitoring electrochemical impedance spectroscopy. The polymer adlayer is exceptionally effective in both reducing background response and maintaining receptive antibody binding efficacy, while the non-Faradaic analysis avoids potential interference from background electro-active molecules. Applied to the detection of even a low molecular weight protein (here, insulin), a linear range from 0.1 to 200 pM and an unprecedented femtomolar detection limit are possible in undiluted blood serum.

Targeting protein modifications in metabolic diseases: molecular mechanisms and targeted therapies.

The ever-increasing prevalence of noncommunicable diseases (NCDs) represents a major public health burden worldwide. The most common form of NCD is metabolic diseases, which affect people of all ages and usually manifest their pathobiology through life-threatening cardiovascular complications. A comprehensive understanding of the pathobiology of metabolic diseases will generate novel targets for improved therapies across the common metabolic spectrum. Protein posttranslational modification (PTM) is an important term that refers to biochemical modification of specific amino acid residues in target proteins, which immensely increases the functional diversity of the proteome. The range of PTMs includes phosphorylation, acetylation, methylation, ubiquitination, SUMOylation, neddylation, glycosylation, palmitoylation, myristoylation, prenylation, cholesterylation, glutathionylation, S-nitrosylation, sulfhydration, citrullination, ADP ribosylation, and several novel PTMs. Here, we offer a comprehensive review of PTMs and their roles in common metabolic diseases and pathological consequences, including diabetes, obesity, fatty liver diseases, hyperlipidemia, and atherosclerosis. Building upon this framework, we afford a through description of proteins and pathways involved in metabolic diseases by focusing on PTM-based protein modifications, showcase the pharmaceutical intervention of PTMs in preclinical studies and clinical trials, and offer future perspectives. Fundamental research defining the mechanisms whereby PTMs of proteins regulate metabolic diseases will open new avenues for therapeutic intervention.

Establishment of virus-induced gene silencing (VIGS) system in Luffa acutangula using Phytoene desaturase (PDS) and tendril synthesis related gene (TEN).

BACKGROUND: Virus-induced gene silencing (VIGS) is a reverse genetics technology that can efficiently and rapidly identify plant gene functions. Although a variety of VIGS vectors have been successfully used in plants, only a few reports on VIGS technology in Luffa exist. RESULTS: In the present study, a new cucumber green mottle mosaic virus (CGMMV)-based VIGS vector, pV190, was applied to establish the CGMMV-VIGS to investigate the feasibility of the silencing system for Luffa. Phytoene desaturase (PDS) gene was initially selected as a VIGS marker gene to construct a recombinant vector. Plants infected with Agrobacterium harboring pV190-PDS successfully induced effective silencing in Luffa, and an effective gene silencing phenotype with obvious photobleaching was observed. To further validate the efficiency, we selected TEN for gene-silencing, which encodes a CYC/TB1-like transcription factor and is involved in tendril development. Luffa plants inoculated with the pV190-TEN exhibited shorter tendril length and nodal positions where tendrils appear are higher compared to those of non-inoculated plants. RT-qPCR showed that the expression levels of PDS and TEN were significantly reduced in the CGMMV-VIGS plants. Moreover, we evaluated the CGMMV-VIGS efficiency in three cucurbits, including cucumber, ridge gourd, and bottle gourd. CONCLUSION: We successfully established a CGMMV-based VIGS system on ridge gourd and used marker genes to identify the feasibility of the silencing system in Luffa leaves and stems.

Maize Antifungal Protein AFP1 Elevates Fungal Chitin Levels by Targeting Chitin Deacetylases and Other Glycoproteins.

Pathogenic fungi convert chitin to chitosan to evade plant perception and disarm chitin-triggered immune responses. Whether plants have evolved factors to counteract this evasion mechanism remains obscure. Here, we decipher the mechanism underlying the antifungal activity of maize secretory mannose-binding cysteine-rich receptor-like secreted protein (CRRSP), antifungal protein 1 (AFP1). AFP1 binds to multiple sites on the surface of sporidial cells, filaments, and germinated spores of the biotrophic fungus Ustilago maydis. It inhibits cell growth and budding, as well as spore germination. AFP1 promiscuously interacts with most chitin deacetylases (CDAs) by recognizing the conserved NodB domain to interfere with the enzyme activity. Deletion of O-mannosyltransferase 4 decreases protein mannosylation, which correlates with reduced AFP1 binding and antifungal activity, suggesting that AFP1 interacts with mannosylated proteins to exhibit an inhibitory effect. AFP1 also has extended inhibitory activity against Saccharomyces cerevisiae; however, AFP1 did not reduce binding to the double ΔΔcda1,2 mutant, suggesting the targets of AFP1 have expanded to other cell surface glycoproteins, probably facilitated by its mannose-binding property. Increasing chitin levels by modulating the activity of cell surface glycoproteins is a universal feature of AFP1 interacting with a broad spectrum of fungi to inhibit their growth. IMPORTANCE Plants alert immune systems by recognizing the fungal pathogen cell wall component chitin via pattern recognition cell surface receptors. Successful fungal pathogens escape the perception by deacetylating chitin to chitosan, which is also necessary for fungal cell development and virulence. Targeting glycoproteins that are associated with regulating chitin metabolism and maintaining cell wall morphogenesis presents an effective strategy to combat fungal pathogens by simultaneously altering cell wall plasticity, activating chitin-triggered immunity, and impairing fungal viability. Our study provides molecular insights into a plant DUF26 domain-containing secretory protein in warding off a broad range of fungal pathogens by acting on more than one glycoprotein target.

Chlorine Dioxide Reprograms Rhizosphere Microbial Communities to Enrich Interactions with Tobacco (Nicotiana tabacum).

For decades chlorine dioxide has been used in water disinfection with excellent results. As the scope of application expands, chlorine dioxide has the potential for soil disinfection. We used amplicon sequencing and gas chromatography-mass spectrometry to compare the changes of four mixed rhizosphere microbial community samples and 12 tobacco leaf volatile samples four months after the flood irrigation with chlorine dioxide in different concentrations (0, 2, 4, 8 mg/l). Phenotypic data of 60 tobacco plants were also collected. The effects of chlorine dioxide on rhizosphere microorganisms were positively correlated with dose gradients. Bacteria responded more strongly in both community structure and metabolic pathways than fungi. Five new bacterial phyla (Firmicutes, Bacteroidota, Myxococcota, Patescibacteria, Verrucomicroboata) appeared in chlorine dioxide treatment groups, while the fungal community only appeared as one new fungal phylum (Basidomycota). Alterations in 271 predicted metabolic bacterial pathways were found. However, in the fungal community were only 10 alternations. The correlations between leaf volatile compounds and rhizosphere microorganisms under the influence of chlorine dioxide treatment could be observed based on network results. However, natural connectivity had already been declining rapidly when less than 20% of the network's nodes were removed. Therefore, the microbe-metabolite network is not stable. It might be why chlorine dioxide treatments did not significantly affect tobacco quality (p = 0.754) and phenotype (p = 0.867). As a comprehensive investigation of chlorine dioxide in agriculture, this study proves the effectiveness and safety of chlorine dioxide soil disinfection and widens the application range of chlorine dioxide.

Ustilago maydis PR-1-like protein has evolved two distinct domains for dual virulence activities.

The diversification of effector function, driven by a co-evolutionary arms race, enables pathogens to establish compatible interactions with hosts. Structurally conserved plant pathogenesis-related PR-1 and PR-1-like (PR-1L) proteins are involved in plant defense and fungal virulence, respectively. It is unclear how fungal PR-1L counters plant defense. Here, we show that Ustilago maydis UmPR-1La and yeast ScPRY1, with conserved phenolic resistance functions, are Ser/Thr-rich region mediated cell-surface localization proteins. However, UmPR-1La has gained specialized activity in sensing phenolics and eliciting hyphal-like formation to guide fungal growth in plants. Additionally, U. maydis hijacks maize cathepsin B-like 3 (CatB3) to release functional CAPE-like peptides by cleaving UmPR-1La's conserved CNYD motif, subverting plant CAPE-primed immunity and promoting fungal virulence. Surprisingly, CatB3 avoids cleavage of plant PR-1s, despite the presence of the same conserved CNYD motif. Our work highlights that UmPR-1La has acquired additional dual roles to suppress plant defense and sustain the infection process of fungal pathogens.

Polyamine pathways interconnect with GABA metabolic processes to mediate the low-temperature response in plants.

Low temperatures are among the most commonly encountered environmental conditions that adversely affect plant growth and development, leading to substantial reductions in crop productivity. Plants have accordingly evolved coordinated mechanisms that confer low-temperature adaptation and resistance. The plant metabolic network, including polyamines (PAs) and γ-aminobutyric acid (GABA) is reprogrammed to ensure that essential metabolic homeostasis is maintained in response to cold stress conditions. Additionally, GABA might serve as a central molecule in the defense system during low-temperature tolerance in plants. However, our understanding of how these metabolites function in conferring cold tolerance is still far from complete. Here, we summarized how PAs and GABA function in conferring cold tolerance, and describe the crucial role of GABA in the mitigation of ROS during cold stress in plants.