ABSTRACT
Dopamine receptors, including D1- and D2-like receptors, are important therapeutic targets in a variety of neurological syndromes, as well as cardiovascular and kidney diseases. Here, we present five cryoelectron microscopy (cryo-EM) structures of the dopamine D1 receptor (DRD1) coupled to Gs heterotrimer in complex with three catechol-based agonists, a non-catechol agonist, and a positive allosteric modulator for endogenous dopamine. These structures revealed that a polar interaction network is essential for catecholamine-like agonist recognition, whereas specific motifs in the extended binding pocket were responsible for discriminating D1- from D2-like receptors. Moreover, allosteric binding at a distinct inner surface pocket improved the activity of DRD1 by stabilizing endogenous dopamine interaction at the orthosteric site. DRD1-Gs interface revealed key features that serve as determinants for G protein coupling. Together, our study provides a structural understanding of the ligand recognition, allosteric regulation, and G protein coupling mechanisms of DRD1.
Subject(s)
GTP-Binding Protein alpha Subunits, Gs/metabolism , Receptors, Dopamine D1/metabolism , Signal Transduction , Allosteric Regulation , Allosteric Site , Amino Acid Motifs , Amino Acid Sequence , Binding Sites , Catechols/metabolism , Cryoelectron Microscopy , Fenoldopam/chemistry , Fenoldopam/pharmacology , GTP-Binding Protein alpha Subunits, Gs/chemistry , GTP-Binding Protein alpha Subunits, Gs/ultrastructure , HEK293 Cells , Humans , Ligands , Models, Molecular , Protein Multimerization , Receptors, Dopamine D1/chemistry , Receptors, Dopamine D1/ultrastructure , Receptors, Dopamine D2/metabolism , Structural Homology, ProteinABSTRACT
Large-scale genetic association studies have identified multiple susceptibility loci for nasopharyngeal carcinoma (NPC), but the underlying biological mechanisms remain to be explored. To gain insights into the genetic etiology of NPC, we conducted a follow-up study encompassing 6,907 cases and 10,472 controls and identified two additional NPC susceptibility loci, 9q22.33 (rs1867277; OR = 0.74, 95% CI = 0.68-0.81, p = 3.08 × 10-11) and 17q12 (rs226241; OR = 1.42, 95% CI = 1.26-1.60, p = 1.62 × 10-8). The two additional loci, together with two previously reported genome-wide significant loci, 5p15.33 and 9p21.3, were investigated by high-throughput sequencing for chromatin accessibility, histone modification, and promoter capture Hi-C (PCHi-C) profiling. Using luciferase reporter assays and CRISPR interference (CRISPRi) to validate the functional profiling, we identified PHF2 at locus 9q22.33 as a susceptibility gene. PHF2 encodes a histone demethylase and acts as a tumor suppressor. The risk alleles of the functional SNPs reduced the expression of the target gene PHF2 by inhibiting the enhancer activity of its long-range (4.3 Mb) cis-regulatory element, which promoted proliferation of NPC cells. In addition, we identified CDKN2B-AS1 as a susceptibility gene at locus 9p21.3, and the NPC risk allele of the functional SNP rs2069418 promoted the expression of CDKN2B-AS1 by increasing its enhancer activity. The overexpression of CDKN2B-AS1 facilitated proliferation of NPC cells. In summary, we identified functional SNPs and NPC susceptibility genes, which provides additional explanations for the genetic association signals and helps to uncover the underlying genetic etiology of NPC development.
Subject(s)
Nasopharyngeal Neoplasms , Humans , Nasopharyngeal Carcinoma/genetics , Nasopharyngeal Neoplasms/genetics , Nasopharyngeal Neoplasms/pathology , Follow-Up Studies , Genetic Predisposition to Disease , Genetic Association Studies , Polymorphism, Single Nucleotide/genetics , Homeodomain Proteins/geneticsABSTRACT
Foot-and-mouth disease virus (FMDV) serotype A is antigenically most variable within serotypes. The structures of conserved and variable antigenic sites were not well resolved. Here, a historical A/AF72 strain from A22 lineage and a latest A/GDMM/2013 strain from G2 genotype of Sea97 lineage were respectively used as bait antigen to screen single B cell antibodies from bovine sequentially vaccinated with A/WH/CHA/09 (G1 genotype of Sea97 lineage), A/GDMM/2013 and A/AF72 antigens. Total of 39 strain-specific and 5 broad neutralizing antibodies (bnAbs) were isolated and characterized. Two conserved antigenic sites were revealed by the Cryo-EM structures of FMDV serotype A with two bnAbs W2 and W125. The contact sites with both VH and VL of W125 were closely around icosahedral threefold axis and covered the B-C, E-F, and H-I loops on VP2 and the B-B knob and H-I loop on VP3; while contact sites with only VH of W2 concentrated on B-B knob, B-C and E-F loops on VP3 scattering around the three-fold axis of viral particle. Additional highly conserved epitopes also involved key residues of VP158, VP1147 and both VP272 / VP1147 as determined respectively by bnAb W153, W145 and W151-resistant mutants. Furthermore, the epitopes recognized by 20 strain-specific neutralization antibodies involved the key residues located on VP3 68 for A/AF72 (11/20) and VP3 175 position for A/GDMM/2013 (9/19), respectively, which revealed antigenic variation between different strains of serotype A. Analysis of antibody-driven variations on capsid of two virus strains showed a relatively stable VP2 and more variable VP3 and VP1. This study provided important information on conserve and variable antigen structures to design broad-spectrum molecular vaccine against FMDV serotype A.
Subject(s)
Foot-and-Mouth Disease Virus , Foot-and-Mouth Disease , Animals , Cattle , Antibodies, Neutralizing , Serogroup , Antibodies, Viral , Broadly Neutralizing Antibodies/genetics , Epitopes , Capsid Proteins/genetics , Antibodies, MonoclonalABSTRACT
BACKGROUND AND AIMS: The common characteristics of alcohol-associated liver injury (ALI) include abnormal liver function, infiltration of inflammatory cells, and generation of oxidative stress. The gastrin-releasing peptide receptor (GRPR) is activated by its neuropeptide ligand, gastrin-releasing peptide (GRP). GRP/GRPR appears to induce the production of cytokines in immune cells and promotes neutrophil migration. However, the effects of GRP/GRPR in ALI are unknown. APPROACH AND RESULTS: We found high GRPR expression in the liver of patients with alcohol-associated steatohepatitis and increased pro-GRP levels in peripheral blood mononuclear cells of these patients compared with that of the control. Increased expression of GRP may be associated with histone H3 lysine 27 acetylation induced by alcohol, which promotes the expression of GRP and then GRPR binding. Grpr-/- and Grprflox/floxLysMCre mice alleviated ethanol-induced liver injury with relieved steatosis, lower serum alanine aminotransferase, aspartate aminotransferase, triglycerides, malondialdehyde, and superoxide dismutase levels, reduced neutrophil influx, and decreased expression and release of inflammatory cytokines and chemokines. Conversely, the overexpression of GRPR showed opposite effects. The pro-inflammatory and oxidative stress roles of GRPR might be dependent on IRF1-mediated Caspase-1 inflammasome and NOX2-dependent reactive oxygen species pathway, respectively. In addition, we verified the therapeutic and preventive effects of RH-1402, a novel GRPR antagonist, for ALI. CONCLUSIONS: A knockout or antagonist of GRPR during excess alcohol intake could have anti-inflammatory and antioxidative roles, as well as provide a platform for histone modification-based therapy for ALI.
Subject(s)
Inflammasomes , Receptors, Bombesin , Humans , Mice , Animals , Receptors, Bombesin/metabolism , Inflammasomes/metabolism , Reactive Oxygen Species/metabolism , Caspase 1/metabolism , Leukocytes, Mononuclear , Gastrin-Releasing Peptide/metabolism , Ethanol , Liver/metabolism , Cytokines/metabolism , Interferon Regulatory Factor-1/metabolismABSTRACT
The extracellular matrix (ECM) mechanical properties regulate biological processes, such as fibroblast-myofibroblast transformation (FMT), which is a crucial component in pelvic organ prolapse (POP) development. The 'Kindlin-2' protein, expressed by fibroblasts, plays an important role in the development of the mesoderm, which is responsible for connective tissue formation; however, the role of Kindlin-2 in FMT remains to be explored. In this study, we aimed to explore the role of Kindlin-2 in FMT as it relates to POP. We found that ECM stiffness induces autophagy to translocate Kindlin-2 to the cytoplasm of L929 cells, where it interacts with and degrades MOB1, thereby facilitating Yes-associated protein (YAP) entry into the nucleus and influencing FMT progression. Stiffness-induced autophagy was inhibited when using an autophagy inhibitor, which blocked the translocation of Kindlin-2 to the cytoplasm and partially reversed high-stiffness-induced FMT. In patients with POP, we observed an increase in cytoplasmic Kindlin-2 and nuclear YAP levels. Similar changes in vaginal wall-associated proteins were observed in a mouse model of acute vaginal injury. In conclusion, Kindlin-2 is a key gene affecting ECM stiffness, which regulates FMT by inducing autophagy and may influence the development of POP.
Subject(s)
Cytoskeletal Proteins , Extracellular Matrix , Muscle Proteins , Myofibroblasts , Animals , Female , Humans , Mice , Cytoplasm/metabolism , Extracellular Matrix/metabolism , Extracellular Matrix Proteins/metabolism , Fibroblasts/metabolism , Myofibroblasts/metabolism , Cytoskeletal Proteins/metabolism , Muscle Proteins/metabolismABSTRACT
The functional brain connectome is highly dynamic over time. However, how brain connectome dynamics evolves during the third trimester of pregnancy and is associated with later cognitive growth remains unknown. Here, we use resting-state functional Magnetic Resonance Imaging (MRI) data from 39 newborns aged 32 to 42 postmenstrual weeks to investigate the maturation process of connectome dynamics and its role in predicting neurocognitive outcomes at 2 years of age. Neonatal brain dynamics is assessed using a multilayer network model. Network dynamics decreases globally but increases in both modularity and diversity with development. Regionally, module switching decreases with development primarily in the lateral precentral gyrus, medial temporal lobe, and subcortical areas, with a higher growth rate in primary regions than in association regions. Support vector regression reveals that neonatal connectome dynamics is predictive of individual cognitive and language abilities at 2 years of age. Our findings highlight network-level neural substrates underlying early cognitive development.
Subject(s)
Brain , Cognition , Connectome , Magnetic Resonance Imaging , Humans , Connectome/methods , Female , Male , Magnetic Resonance Imaging/methods , Cognition/physiology , Infant, Newborn , Brain/growth & development , Brain/diagnostic imaging , Brain/physiology , Child, Preschool , Language Development , Child Development/physiologyABSTRACT
Alcohol-related liver disease (ALD) and metabolic dysfunction-associated steatotic liver disease (MASLD), two main types of steatotic liver disease (SLDs), are characterized by a wide spectrum of several different liver disorders, including simple steatosis, steatohepatitis, cirrhosis, and hepatocellular carcinoma. Multiple immune cell-mediated inflammatory responses not only orchestrate the killing and removal of infected/damaged cells but also exacerbate the development of SLDs when excessive or persistent inflammation occurs. In recent years, single-cell and spatial transcriptome analyses have revealed the heterogeneity of liver-infiltrated immune cells in ALD and MASLD, revealing a new immunopathological picture of SLDs. In this review, we will emphasize the roles of several key immune cells in the pathogenesis of ALD and MASLD and discuss inflammation-based approaches for effective SLD intervention. In conclusion, the study of immunological mechanisms, especially highly specific immune cell population functions, may provide novel therapeutic opportunities for this life-threatening disease.
ABSTRACT
Epstein-Barr virus (EBV) is detected in nearly 100% of nonkeratinizing nasopharyngeal carcinoma (NPC) and EBV-based biomarkers are used for NPC screening in endemic regions. Immunoglobulin A (IgA) against EBV nuclear antigen 1 (EBNA1) and viral capsid antigen (VCA), and recently identified anti-BNLF2b antibodies have been shown to be the most effective screening tool; however, the screening efficacy still needs to be improved. This study developed a multiplex serological assay by testing IgA and immunoglobulin G (IgG) antibodies against representative EBV antigens that are highly transcribed in NPC and/or function crucially in viral reactivation, including BALFs, BNLF2a/b, LF1, LF2, and Zta (BZLF1). Among them, BNLF2b-IgG had the best performance distinguishing NPC patients from controls (area under the curve: 0.951, 95% confidence interval [CI]: 0.913-0.990). Antibodies to lytic antigens BALF2 and VCA were significantly higher in advanced-stage than in early-stage tumors; in contrast, antibodies to latent protein EBNA1 and early lytic antigen BNLF2b were not correlated with tumor progression. Accordingly, a novel strategy combining EBNA1-IgA and BNLF2b-IgG was proposed and validated improving the integrated discrimination by 15.8% (95% CI: 9.8%-21.7%, p < .0001) compared with the two-antibody method. Furthermore, we found EBV antibody profile in patients was more complicated compared with that in healthy carriers, in which stronger correlations between antibodies against different phases of antigens were observed. Overall, our serological assay indicated that aberrant latent infection of EBV in nasopharyngeal epithelial cells was probably a key step in NPC initiation, while more lytic protein expression might be involved in NPC progression.
ABSTRACT
Plasma levels of oncofetal chondroitin sulfate (ofCS)-modified CD44 have emerged as a promising biomarker for multi-cancer detection. Here, we explored its potential to predict the survival of patients with lung cancer. A prospective observational cohort was conducted involving 274 newly diagnosed patients with lung cancer at the Sun Yat-sen University Cancer Center from 2013 to 2015. The plasma levels of ofCS-modified CD44 were measured, and Cox regression analysis was performed to assess the association between plasma-modified CD44 levels and overall survival (OS) as well as other prognostic outcomes. Prognostic nomograms were constructed based on plasma ofCS-modified CD44 levels to predict survival outcomes for patients with lung cancer. Patients with high expression ofCS-modified CD44 exhibited significantly worse outcomes in terms of OS (HR = 1.61, 95%CI = 1.13-2.29, p = 0.009) and progression-free survival (PFS). These findings were consistent across various analyses. The concordance index of the prognostic nomogram for predicting OS in both the training set and validation set were 0.723 and 0.737, respectively. Additionally, time-dependent receiver operating characteristic (ROC) curves showed that the nomogram could serve as a useful tool for predicting OS in patients with lung cancer. Plasma ofCS-modified CD44 may serve as an independent prognosis marker for patients with lung cancer. Further validation of its predictive value could enhance prognostic assessment and guide personalized treatment strategies for patients with lung cancer.
ABSTRACT
BACKGROUND: The trajectory of attention-deficit hyperactivity disorder (ADHD) symptoms in children and adolescents, encompassing descending, stable, and ascending patterns, delineates their ADHD status as remission, persistence or late onset. However, the neural and genetic underpinnings governing the trajectory of ADHD remain inadequately elucidated. METHODS: In this study, we employed neuroimaging techniques, behavioral assessments, and genetic analyses on a cohort of 487 children aged 6-15 from the Children School Functions and Brain Development project at baseline and two follow-up tests for 1 year each (interval 1: 1.14 ± 0.32 years; interval 2: 1.14 ± 0.30 years). We applied a Latent class mixed model (LCMM) to identify the developmental trajectory of ADHD symptoms in children and adolescents, while investigating the neural correlates through gray matter volume (GMV) analysis and exploring the genetic underpinnings using polygenic risk scores (PRS). RESULTS: This study identified three distinct trajectories (ascending-high, stable-low, and descending-medium) of ADHD symptoms from childhood through adolescence. Utilizing the linear mixed-effects (LME) model, we discovered that attention hub regions served as the neural basis for these three developmental trajectories. These regions encompassed the left anterior cingulate cortex/medial prefrontal cortex (ACC/mPFC), responsible for inhibitory control; the right inferior parietal lobule (IPL), which facilitated conscious focus on exogenous stimuli; and the bilateral middle frontal gyrus/precentral gyrus (MFG/PCG), accountable for regulating both dorsal and ventral attention networks while playing a crucial role in flexible modulation of endogenous and extrinsic attention. Furthermore, our findings revealed that individuals in the ascending-high group exhibited the highest PRS for ADHD, followed by those in the descending-medium group, with individuals in the stable-low group displaying the lowest PRS. Notably, both ascending-high and descending-medium groups had significantly higher PRS compared to the stable-low group. CONCLUSIONS: The developmental trajectory of ADHD symptoms in the general population throughout childhood and adolescence can be reliably classified into ascending-high, stable-low, and descending-medium groups. The bilateral MFG/PCG, left ACC/mPFC, and right IPL may serve as crucial brain regions involved in attention processing, potentially determining these trajectories. Furthermore, the ascending-high pattern of ADHD symptoms exhibited the highest PRS for ADHD.
Subject(s)
Attention Deficit Disorder with Hyperactivity , Humans , Attention Deficit Disorder with Hyperactivity/genetics , Attention Deficit Disorder with Hyperactivity/physiopathology , Child , Adolescent , Male , Female , Magnetic Resonance Imaging , Brain/diagnostic imaging , Brain/growth & development , Gray Matter/diagnostic imaging , Gray Matter/pathology , Neuroimaging , Cohort StudiesABSTRACT
Skin injury repair is a dynamic process involving a series of interactions over time and space. Linking human physiological processes with materials' changes poses a significant challenge. To match the wound healing process, a spatiotemporal controllable biomimetic skin is developed, which comprises a three-dimensional (3D) printed membrane as the epidermis, a cell-containing hydrogel as the dermis, and a cytokine-laden hydrogel as the hypodermis. In the initial stage of the biomimetic skin repair wound, the membrane frame aids wound closure through pre-tension, while cells proliferate within the hydrogel. Next, as the frame disintegrates over time, cells released from the hydrogel migrate along the residual membrane. Throughout the process, continuous cytokines release from the hypodermis hydrogel ensures comprehensive nourishment. The findings reveal that in the rat full-thickness skin defect model, the biomimetic skin demonstrated a wound closure rate eight times higher than the blank group, and double the collagen content, particularly in the early repair process. Consequently, it is reasonable to infer that this biomimetic skin holds promising potential to accelerate wound closure and repair. This biomimetic skin with mechanobiological effects and spatiotemporal regulation emerges as a promising option for tissue regeneration engineering.
Subject(s)
Skin , Wound Healing , Animals , Rats , Hydrogels/chemistry , Biomimetics/methods , Biomimetic Materials/chemistry , Tissue Engineering/methods , Humans , Skin, Artificial , Rats, Sprague-Dawley , Printing, Three-DimensionalABSTRACT
Tissue development is mediated by a combination of mechanical and biological signals. Currently, there are many reports on biological signals regulating repair. However, insufficient attention is paid to the process of mechanical regulation, especially the active mechanical regulation in vivo, which has not been realized. Herein, a novel dynamically regulated repair system for both in vitro and in vivo applications is developed, which utilizes magnetic nanoparticles as non-contact actuators to activate hydrogels. The magnetic hydrogel can be periodically activated and deformed to different amplitudes by a dynamic magnetic system. An in vitro skin model is used to explore the impact of different dynamic stimuli on cellular mechano-transduction signal activation and cell differentiation. Specifically, the effect of mechanical stimulation on the phenotypic transition of fibroblasts to myofibroblasts is investigated. Furthermore, in vivo results verify that dynamic massage can simulate and enhance the traction effect in skin defects, thereby accelerating the wound healing process by promoting re-epithelialization and mediating dermal contraction.
Subject(s)
Bandages , Massage , Wound Healing , Animals , Massage/methods , Fibroblasts , Humans , Hydrogels/chemistry , Cell Differentiation , Skin , Mice , Myofibroblasts/cytologyABSTRACT
Bone regeneration is a well-orchestrated process synergistically involving inflammation, angiogenesis, and osteogenesis. Therefore, an effective bone graft should be designed to target multiple molecular events and biological demands during the bone healing process. In this study, a biodegradable gelatin methacryloyl (GelMA)-based Janus microsphere delivery system containing calcium phosphate oligomer (CPO) and bone morphogenetic protein-2 (BMP-2) is developed based on natural biological events. The exceptional adjustability of GelMA facilitates the controlled release and on-demand application of biomolecules, and optimized delivery profiles of CPO and BMP-2 are explored. The sustained release of CPO during the initial healing stages contributes to early immunomodulation and promotes mineralization in the late stage. Meanwhile, the administration of BMP-2 at a relatively high concentration within the therapeutic range enhances the osteoinductive property. This delivery system, with fine-tuned release patterns, induces M2 macrophage polarization and creates a conducive immuno-microenvironment, which in turn facilitates effective bone regeneration in vivo. Collectively, this study proposes a bottom-up concept, aiming to develop a user-friendly and easily controlled delivery system targeting individual biological events, which may offer a new perspective on developing function-optimized biomaterials for clinical use.
ABSTRACT
BACKGROUND: The previous first-in-human study established the preliminary safety and effectiveness of the novel thin-strut iron bioresorbable scaffold (IBS). The current study aims to directly compare the imaging and physiological efficacy, and clinical outcomes of IBS with contemporary metallic drug-eluting stents (DES). METHODS: A total of 518 patients were randomly allocated to treatment with IBS (257 patients) or metallic DES (261 patients) from 36 centers in China. The study is powered to test noninferiority of the IBS compared with the metallic everolimus-eluting stent in terms of the primary endpoint of in-segment late lumen loss at 2 years, and major secondary endpoints including 2-year quantitative flow ratio and cross-sectional mean flow area measured by optical coherence tomography (OCT) (limited to the OCT subgroup, 25 patients in each group). CONCLUSION: This will be the first powered randomized trial investigating the safety and efficacy of the novel thin-strut IBS compared to a contemporary metallic DES. The findings will provide valuable evidence for future research of this kind and the application of metallic bioresorbable scaffolds.
Subject(s)
Absorbable Implants , Coronary Artery Disease , Drug-Eluting Stents , Everolimus , Sirolimus , Tomography, Optical Coherence , Humans , Everolimus/administration & dosage , Everolimus/pharmacology , Coronary Artery Disease/therapy , Coronary Artery Disease/surgery , Sirolimus/analogs & derivatives , Sirolimus/administration & dosage , Sirolimus/pharmacology , Tomography, Optical Coherence/methods , Male , Female , Middle Aged , Prosthesis Design , Iron , Tissue Scaffolds , Percutaneous Coronary Intervention/methods , Immunosuppressive Agents/administration & dosage , Immunosuppressive Agents/pharmacology , Treatment OutcomeABSTRACT
Hydrogel materials show promise for diverse applications, particular as biocompatible materials due to their high water content. Despite advances in hydrogel technology in recent years, their application is often severely limited by inadequate mechanical properties and time-consuming fabrication processes. Here we report a rapid hydrogel preparation strategy that achieves the simultaneous photo-crosslinking and establishment of biomimetic soft-hard material interface microstructures. These biomimetic interfacial-bonding nanocomposite hydrogels are prepared within seconds and feature clearly separated phases but have a strongly bonded interface. Due to effective interphase load transfer, biomimetic interfacial-bonding nanocomposite gels achieve an ultrahigh toughness (138 MJ m-3) and exceptional tensile strength (15.31 MPa) while maintaining a structural stability that rivals or surpasses that of commonly used elastomer (non-hydrated) materials. Biomimetic interfacial-bonding nanocomposite gels can be fabricated into arbitrarily complex structures via three-dimensional printing with micrometre-level precision. Overall, this work presents a generalizable preparation strategy for hydrogel materials and acrylic elastomers that will foster potential advances in soft materials.
ABSTRACT
Soil and rhizosphere bacteria act as a rich source of secondary metabolites, effectively fighting against a diverse array of pathogens. Certain Pseudomonas species harbor biosynthetic gene clusters for producing both pyoluteorin and 2,4-diacetylphloroglucinol (2,4-DAPG), which are polyketides that exhibit highly similar antimicrobial spectrum against bacteria and fungi or oomycete. A complex cross talk exists between pyoluteorin and 2,4-DAPG biosynthesis, and production of 2,4-DAPG was strongly repressed by pyoluteorin, yet the underlying mechanism is still elusive. In this study, we find that the TetR family transcription factor PhlH is involved in the cross talk between pyoluteorin and 2,4-DAPG biosynthesis. PhlH binds to a palindromic sequence within the promoter of phlG (PphlG), which encodes a C-C bond hydrolase responsible for degrading 2,4-DAPG. As a signaling molecule, pyoluteorin disrupts the PhlH-PphlG complex by binding to PhlH, leading to decreased levels of 2,4-DAPG. Proteomics data suggest that pyoluteorin regulates multiple physiological processes including fatty acid biosynthesis and transportation of taurine, siderophore, and amino acids. Our work not only reveals a novel mechanism of cross talk between pyoluteorin and 2,4-DAPG biosynthesis, but also highlights pyoluteorin's role as a messenger in the complex communication network of Pseudomonas.IMPORTANCEAntibiosis serves as a crucial defense mechanism for microbes against invasive bacteria and resource competition. These bacteria typically orchestrate the production of multiple antibiotics in a coordinated fashion, wherein the synthesis of one antibiotic inhibits the generation of another. This strategic coordination allows the bacterium to focus its resources on producing the most advantageous antibiotic under specific circumstances. However, the underlying mechanisms of distinct antibiotic production in bacterial cells remain largely elusive. In this study, we reveal that the TetR family transcription factor PhlH detects the secondary metabolite pyoluteorin and mediates the cross talk between pyoluteorin and 2,4-DAPG biosynthesis in the biocontrol strain Pseudomonas protegens Pf-5. These findings hold promise for future research, potentially informing the manipulation of these systems to enhance the effectiveness of biocontrol agents.
Subject(s)
Phenols , Phloroglucinol/analogs & derivatives , Pseudomonas fluorescens , Pyrroles , Transcription Factors , Transcription Factors/genetics , Transcription Factors/metabolism , Gene Expression Regulation, Bacterial , Pseudomonas/metabolism , Anti-Bacterial Agents/pharmacology , Pseudomonas fluorescens/geneticsABSTRACT
As a climbing organ, the tendril undergoes rapid elongation to increase its length to locate support within a short growth time. However, the molecular mechanism underlying this observation is poorly understood. Here, tendril development was divided into 4 stages in cucumber (Cucumis sativus L.) along with its growth. Phenotypic observations and section analyses showed that the rapid elongation of tendril primarily happened during stage 3 and was mainly due to cell expansion. RNA-seq analysis showed that PACLOBUTRAZOL-RESISTANCE4 (CsPRE4) was highly expressed in the tendril. Our RNAi studies in cucumber and transgenic overexpression in Arabidopsis (Arabidopsis thaliana) suggested that CsPRE4 functions as a conserved activator of cell expansion to promote cell expansion and tendril elongation. Through a triantagonistic HLH (helix-loop-helix)-HLH-bHLH (basic helix-loop-helix) cascade, CsPRE4-CsPAR1 (PHYTOCHROME RAPIDLY REGULATED1)-CsBEE1 (BR-ENHANCED EXPRESSION 1), CsPRE4 released the transcription factor CsBEE1, which activated expansin A12 (CsEXPA12) to loosen the cell wall structure in tendrils. Gibberellin (GA) promoted tendril elongation by modulating cell expansion, and CsPRE4 expression was induced by exogenous GA treatment, suggesting that CsPRE4 acts downstream of GA in regulating tendril elongation. In summary, our work suggested a CsPRE4-CsPAR1-CsBEE1-CsEXPA12 pathway in regulating cell expansion in cucumber tendrils, which might enable rapid tendril elongation to quickly locate support.
Subject(s)
Arabidopsis Proteins , Arabidopsis , Cucumis sativus , Cucumis sativus/genetics , Cucumis sativus/metabolism , Transcription Factors/metabolism , Arabidopsis Proteins/metabolism , Basic Helix-Loop-Helix Transcription Factors/metabolism , Gene Expression Regulation, PlantABSTRACT
Direct optical detection and imaging of single nanoparticles on a substrate in wide field underpin vast applications across different research fields. However, speckles originating from the unavoidable random surface undulations of the substrate ultimately limit the size of the decipherable nanoparticles by the current optical techniques, including the ultrasensitive interferometric scattering microscopy (iSCAT). Here, we report a defocus-integration iSCAT to suppress the speckle noise and to enhance the detection and imaging of single nanoparticles on an ultra-flat glass substrate and a silicon wafer. In particular, we discover distinct symmetry properties of the scattering phase between the nanoparticle and the surface undulations that cause the speckles. Consequently, we develop the defocus-integration technique to suppress the speckles. We experimentally achieve an enhancement of the signal-to-noise ratio by 6.9 dB for the nanoparticle detection. We demonstrate that the technique is generally applicable for nanoparticles of various materials and for both low and high refractive index substrates.
ABSTRACT
Myocardial infarction (MI) is a serious threat to human health. Although monotherapy with pulsed electromagnetic fields (PEMFs) or adipose-derived stem cells (ADSCs) has been reported to have positive effect on the treatment of MI, a satisfactory outcome has not yet been achieved. In recent years, combination therapy has attracted widespread interest. Herein, we explored the synergistic therapeutic effect of combination therapy with PEMFs and ADSCs on MI and found that the combination of PEMFs and ADSCs effectively reduced infarct size, inhibited cardiomyocyte apoptosis and protected the cardiac function in mice with MI. In addition, bioinformatics analysis and RT-qPCR showed that the combination therapy could affect apoptosis by regulating the expression of miR-20a-5p. A dual-luciferase reporter gene assay also confirmed that the miR-20a-5p could target E2F transcription factor 1 (E2F1) and inhibit cardiomyocyte apoptosis by regulating the E2F1/p73 signaling pathway. Therefore, our study systematically demonstrated the effectiveness of combination therapy on the inhibition of cardiomyocyte apoptosis by regulating the miR-20a-5p/E2F1/p73 signaling pathway in mice with MI. Thus, our study underscored the effectiveness of the combination of PEMFs and ADSCs and identified miR-20a-5p as a promising therapeutic target for the treatment of MI in the future.
Subject(s)
Electromagnetic Fields , MicroRNAs , Myocardium , Animals , Mice , Apoptosis/genetics , E2F1 Transcription Factor/genetics , E2F1 Transcription Factor/metabolism , MicroRNAs/genetics , MicroRNAs/metabolism , Myocardium/metabolism , Signal Transduction , Mesenchymal Stem Cells/metabolismABSTRACT
BACKGROUND: Brain metastasis is a common outcome in non-small cell lung cancer, and despite aggressive treatment, its clinical outcome is still frustrating. In recent years, immunotherapy has been developing rapidly, however, its therapeutic outcomes for primary lung cancer and brain metastases are not the same, suggesting that there may be differences in the immune microenvironment of primary lung cancer and brain metastases, however, we currently know little about these differences. METHODS: Seventeen paired samples of NSCLC and their brain metastases and 45 other unpaired brain metastases samples were collected for the current study. Immunohistochemical staining was performed on all samples for the following markers: immune checkpoints CTLA-4, PD-1, PD-L1, B7-H3, B7-H4, IDO1, and EphA2; tumor-infiltrating lymphocytes (TILs) CD3, CD4, CD8, and CD20; tumor-associated microglia/macrophages (TAMs) CD68 and CD163; and tumor proliferation index Ki-67. The differences in expression of these markers were compared in 17 paired samples, and the effect of the expression level of these markers on the prognosis of patients was analyzed in lung adenocarcinoma brain metastases samples. Subsequently, multiplex immunofluorescence staining was performed in a typical lung-brain paired sample based on the aforementioned results. The multiplex immunofluorescence staining results revealed the difference in tumor immune microenvironment between primary NSCLC and brain metastases. RESULTS: In 17 paired lesions, the infiltration of CTLA-4+ (P = 0.461), PD-1+ (P = 0.106), CD3+ (P = 0.045), CD4+ (P = 0.037), CD8+ (P = 0.008), and CD20+ (P = 0.029) TILs in brain metastases were significantly decreased compared with primary tumors. No statistically significant difference was observed in the CD68 (P = 0.954) and CD163 (P = 0.654) TAM infiltration between primary NSCLC and paired brain metastases. In all the brain metastases lesions, the expression of PD-L1 is related to the time interval of brain metastases in NSCLC. In addition, the Cox proportional hazards regression models showed high expression of B7-H4 (hazard ratio [HR] = 3.276, 95% confidence interval [CI] 1.335-8.041, P = 0.010) and CD68 TAM infiltration (HR = 3.775, 95% CI 1.419-10.044, P = 0.008) were independent prognosis factors for lung adenocarcinoma brain metastases patients. CONCLUSIONS: Both temporal and spatial heterogeneity is present between the primary tumor and brain metastases of NCSLC. Brain metastases lesions exhibit a more immunosuppressive tumor immune microenvironment. B7-H4 and CD68+ TAMs may have potential therapeutic value for lung adenocarcinoma brain metastases patients.