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Journal of Nanobiotechnology Jun 2024Photothermal therapy (PTT) is a promising cancer treatment method due to its ability to induce tumor-specific T cell responses and enhance therapeutic outcomes. However,...
Photothermal therapy (PTT) is a promising cancer treatment method due to its ability to induce tumor-specific T cell responses and enhance therapeutic outcomes. However, incomplete PTT can leave residual tumors that often lead to new metastases and decreased patient survival in clinical scenarios. This is primarily due to the release of ATP, a damage-associated molecular pattern that quickly transforms into the immunosuppressive metabolite adenosine by CD39, prevalent in the tumor microenvironment, thus promoting tumor immune evasion. This study presents a photothermal nanomedicine fabricated by electrostatic adsorption among the Fe-doped polydiaminopyridine (Fe-PDAP), indocyanine green (ICG), and CD39 inhibitor sodium polyoxotungstate (POM-1). The constructed Fe-PDAP@ICG@POM-1 (FIP) can induce tumor PTT and immunogenic cell death when exposed to a near-infrared laser. Significantly, it can inhibit the ATP-adenosine pathway by dual-directional immunometabolic regulation, resulting in increased ATP levels and decreased adenosine synthesis, which ultimately reverses the immunosuppressive microenvironment and increases the susceptibility of immune checkpoint blockade (aPD-1) therapy. With the aid of aPD-1, the dual-directional immunometabolic regulation strategy mediated by FIP can effectively suppress/eradicate primary and distant tumors and evoke long-term solid immunological memory. This study presents an immunometabolic control strategy to offer a salvage option for treating residual tumors following incomplete PTT.
Topics: Animals; Photothermal Therapy; Immunotherapy; Mice; Nanomedicine; Tumor Microenvironment; Cell Line, Tumor; Humans; Indocyanine Green; Neoplasms; Adenosine Triphosphate; Adenosine; Mice, Inbred C57BL; Apyrase; Female; Phototherapy
PubMed: 38915007
DOI: 10.1186/s12951-024-02643-w -
ELife Jun 2024Allosteric cooperativity between ATP and substrates is a prominent characteristic of the cAMP-dependent catalytic subunit of protein kinase A (PKA-C). This long-range...
Allosteric cooperativity between ATP and substrates is a prominent characteristic of the cAMP-dependent catalytic subunit of protein kinase A (PKA-C). This long-range synergistic action is involved in substrate recognition and fidelity, and it may also regulate PKA's association with regulatory subunits and other binding partners. To date, a complete understanding of this intramolecular mechanism is still lacking. Here, we integrated NMR(Nuclear Magnetic Resonance)-restrained molecular dynamics simulations and a Markov State Model to characterize the free energy landscape and conformational transitions of PKA-C. We found that the apoenzyme populates a broad free energy basin featuring a conformational ensemble of the active state of PKA-C (ground state) and other basins with lower populations (excited states). The first excited state corresponds to a previously characterized inactive state of PKA-C with the αC helix swinging outward. The second excited state displays a disrupted hydrophobic packing around the regulatory (R) spine, with a flipped configuration of the F100 and F102 residues at the αC-β4 loop. We validated the second excited state by analyzing the F100A mutant of PKA-C, assessing its structural response to ATP and substrate binding. While PKA-C preserves its catalytic efficiency with Kemptide, this mutation rearranges the αC-β4 loop conformation, interrupting the coupling of the two lobes and abolishing the allosteric binding cooperativity. The highly conserved αC-β4 loop emerges as a pivotal element to control the synergistic binding of nucleotide and substrate, explaining how mutations or insertions near or within this motif affect the function and drug sensitivity in homologous kinases.
Topics: Molecular Dynamics Simulation; Allosteric Regulation; Adenosine Triphosphate; Catalytic Domain; Cyclic AMP-Dependent Protein Kinases; Protein Conformation; Protein Binding; Nucleotides; Substrate Specificity; Cyclic AMP-Dependent Protein Kinase Catalytic Subunits
PubMed: 38913408
DOI: 10.7554/eLife.91506 -
Scientific Reports Jun 2024Microglia, brain-resident macrophages, can acquire distinct functional phenotypes, which are supported by differential reprogramming of cell metabolism. These...
Microglia, brain-resident macrophages, can acquire distinct functional phenotypes, which are supported by differential reprogramming of cell metabolism. These adaptations include remodeling in glycolytic and mitochondrial metabolic fluxes, potentially altering energy substrate availability at the tissue level. This phenomenon may be highly relevant in the brain, where metabolism must be precisely regulated to maintain appropriate neuronal excitability and synaptic transmission. Direct evidence that microglia can impact on neuronal energy metabolism has been widely lacking, however. Combining molecular profiling, electrophysiology, oxygen microsensor recordings and mathematical modeling, we investigated microglia-mediated disturbances in brain energetics during neuroinflammation. Our results suggest that proinflammatory microglia showing enhanced nitric oxide release and decreased CX3CR1 expression transiently increase the tissue lactate/glucose ratio that depends on transcriptional reprogramming in microglia, not in neurons. In this condition, neuronal network activity such as gamma oscillations (30-70 Hz) can be fueled by increased ATP production in mitochondria, which is reflected by elevated oxygen consumption. During dysregulated inflammation, high energy demand and low glucose availability can be boundary conditions for neuronal metabolic fitness as revealed by kinetic modeling of single neuron energetics. Collectively, these findings indicate that metabolic flexibility protects neuronal network function against alterations in local substrate availability during moderate neuroinflammation.
Topics: Animals; Neurons; Energy Metabolism; Microglia; Mice; Neuroinflammatory Diseases; Glucose; Mitochondria; Nitric Oxide; Lactic Acid; Nerve Net; Brain; Oxygen Consumption; Adenosine Triphosphate; Inflammation; Male; Mice, Inbred C57BL
PubMed: 38909138
DOI: 10.1038/s41598-024-64872-1 -
Journal of Dairy Science Jun 2024Interventions targeting the gut microbiota, such as fecal microbiota transplantation, prove effective in repairing the intestinal barrier and facilitating the recovery...
Changes in Rumen Epithelial Morphology and Transcriptome, Rumen Metabolome, and Blood Biochemical Parameters in Lactating Dairy Cows with Subacute Rumen Acidosis Following Rumen Content Transplantation.
Interventions targeting the gut microbiota, such as fecal microbiota transplantation, prove effective in repairing the intestinal barrier and facilitating the recovery of its function and metabolism. However, the regulatory mechanisms governing the remodeling of rumen epithelial morphology and function, rumen metabolism, and host metabolism in cows of subacute ruminal acidosis (SARA) remain poorly understood. Here, we explored the changes in rumen epithelial morphology and transcriptome, rumen metabolome, and blood biochemical parameters in SARA cows following rumen content transplantation (RCT). The entire experiment consisted of 2 periods: the SARA induction period and the RCT period. During the SARA induction period, 12 ruminally cannulated lactating Holstein cows were randomly allocated into 2 groups, fed either a conventional diet [CON; n = 4; 40% concentrate, dry matter (DM) basis] or a high-grain diet (HG; n = 8; 60% concentrate, DM basis). Following the SARA induction period, the RCT period started. The HG cows were randomly assigned to 2 groups: the donor-recipient (DR) group and the self-recipient (SR) group. Rumen contents were entirely removed from both groups before RCT. For the DR group, cows were administered 70% rumen content from the CON cows, paired based on comparable body weight; for the SR group, each cow received 70% self-derived rumen content. The results revealed no significant differences in the thicknesses of the stratum corneum, granulosum, and spinosum/basale layers, as well as the total depth of the epithelium between the SR and DR groups. All these measurements exhibited a decreasing trend and fluctuations over time after the transfer. Notably, these fluctuations tended to stabilize at 13 or 16 d after RCT in the SR group, whereas they tended to stabilize after 8 or 13 d of transfer for the DR group. Transcriptome sequencing revealed that a total of 277 differentially expressed genes (DEGs) were identified between the 2 groups. Enrichment analysis showed that the DEGs were significantly enriched in 11 Gene Ontology biological processes and 14 KEGG pathways. The DEGs corresponding to almost any of these 11 biological process terms and 14 pathways showed mixed up- or downregulation following RCT. Metabolomics analysis indicated that a total of 33 differential metabolites were detected between the SR and DR groups, mainly enriched in 5 key metabolic pathways, including plant polysaccharides and starch degradation, lipid metabolism, amino sugar and nucleotide metabolism, purine metabolism, and Krebs cycle. Among them, the levels of differential metabolites associated with the degradation of plant polysaccharides and starches, metabolism of amino sugars and nucleotides, and purine metabolism pathways were significantly elevated in the DR cows. The results of blood biochemical parameters showed that the triglyceride concentration of the DR cows was increased than that of the SR cows, comparable to the level observed in the CON cows during the SARA induction period. Generally, our findings indicated that RCT facilitated the recovery of rumen epithelial morphological structure but did not promote its function recovery. Moreover, RCT enhanced rumen plant polysaccharide and starch degradation, amino sugar and nucleotide sugar metabolism, as well as purine metabolism. Additionally, it further promoted the recovery of plasma metabolites related to lipid metabolism.
PubMed: 38908691
DOI: 10.3168/jds.2024-24694 -
Nature Communications Jun 2024Adenosine-5'-triphosphate (ATP), the primary energy currency in cellular processes, drives metabolic activities and biosynthesis. Despite its importance, understanding...
Adenosine-5'-triphosphate (ATP), the primary energy currency in cellular processes, drives metabolic activities and biosynthesis. Despite its importance, understanding intracellular ATP dynamics' impact on bioproduction and exploiting it for enhanced bioproduction remains largely unexplored. Here, we harness an ATP biosensor to dissect ATP dynamics across different growth phases and carbon sources in multiple microbial strains. We find transient ATP accumulations during the transition from exponential to stationary growth phases in various conditions, coinciding with fatty acid (FA) and polyhydroxyalkanoate (PHA) production in Escherichia coli and Pseudomonas putida, respectively. We identify carbon sources (acetate for E. coli, oleate for P. putida) that elevate steady-state ATP levels and boost FA and PHA production. Moreover, we employ ATP dynamics as a diagnostic tool to assess metabolic burden, revealing bottlenecks that limit limonene bioproduction. Our results not only elucidate the relationship between ATP dynamics and bioproduction but also showcase its value in enhancing bioproduction in various microbial species.
Topics: Adenosine Triphosphate; Biosensing Techniques; Escherichia coli; Pseudomonas putida; Fatty Acids; Polyhydroxyalkanoates; Energy Metabolism; Carbon; Oleic Acid
PubMed: 38906854
DOI: 10.1038/s41467-024-49579-1 -
Plant Signaling & Behavior Dec 2024Extracellular ATP (eATP) orchestrates vital processes in plants, akin to its role in animals. P2K1 is a crucial receptor mediating eATP effects. Immunoprecipitation...
Extracellular ATP (eATP) orchestrates vital processes in plants, akin to its role in animals. P2K1 is a crucial receptor mediating eATP effects. Immunoprecipitation tandem mass spectrometry data highlighted FERONIA's significant interaction with P2K1, driving us to explore its role in eATP signaling. Here, we investigated putative P2K1-interactor, FERONIA, which is a versatile receptor kinase pivotal in growth and stress responses. We employed a FERONIA loss-of-function mutant, , to dissect its effects on eATP signaling. Interestingly, showed distinct calcium responses compared to wild type, while eATP-responsive genes were constitutively upregulated in . Additionally, displayed insensitivity to eATP-regulated root growth and reduced cell wall accumulation. Together, these results uncover a role for FERONIA in regulating eATP signaling. Overall, our study deepens our understanding of eATP signaling, revealing the intricate interplay between P2K1 and FERONIA impacting the interface between growth and defense.
Topics: Plant Roots; Signal Transduction; Arabidopsis Proteins; Arabidopsis; Adenosine Triphosphate; Gene Expression Regulation, Plant; Phosphotransferases; Protein Serine-Threonine Kinases
PubMed: 38905329
DOI: 10.1080/15592324.2024.2370706 -
NPJ Biofilms and Microbiomes Jun 2024Bacteria induced metamorphosis observed in nearly all marine invertebrates. However, the mechanism of bacteria regulating the larvae-juvenile metamorphosis remains...
Bacteria induced metamorphosis observed in nearly all marine invertebrates. However, the mechanism of bacteria regulating the larvae-juvenile metamorphosis remains unknown. Here, we test the hypothesis that c-di-GMP, a ubiquitous bacterial second-messenger molecule, directly triggers the mollusc Mytilus coruscus larval metamorphosis via the stimulator of interferon genes (STING) receptor. We determined that the deletion of c-di-GMP synthesis genes resulted in reduced c-di-GMP levels and biofilm-inducing activity on larval metamorphosis, accompanied by alterations in extracellular polymeric substances. Additionally, c-di-GMP extracted from tested varying marine bacteria all exhibited inducing activity on larval metamorphosis. Simultaneously, through pharmacological and molecular experiments, we demonstrated that M. coruscus STING (McSTING) participates in larval metamorphosis by binding with c-di-GMP. Our findings reveal that new role of bacterial c-di-GMP that triggers mussel larval metamorphosis transition, and extend knowledge in the interaction of bacteria and host development in marine ecosystems.
Topics: Animals; Metamorphosis, Biological; Larva; Cyclic GMP; Biofilms; Mytilus; Bacteria; Membrane Proteins
PubMed: 38902226
DOI: 10.1038/s41522-024-00523-7 -
Nature Communications Jun 2024C2'-halogenation has been recognized as an essential modification to enhance the drug-like properties of nucleotide analogs. The direct C2'-halogenation of the...
C2'-halogenation has been recognized as an essential modification to enhance the drug-like properties of nucleotide analogs. The direct C2'-halogenation of the nucleotide 2'-deoxyadenosine-5'-monophosphate (dAMP) has recently been achieved using the Fe(II)/α-ketoglutarate-dependent nucleotide halogenase AdaV. However, the limited substrate scope of this enzyme hampers its broader applications. In this study, we report two halogenases capable of halogenating 2'-deoxyguanosine monophosphate (dGMP), thereby expanding the family of nucleotide halogenases. Computational studies reveal that nucleotide specificity is regulated by the binding pose of the phosphate group. Based on these findings, we successfully engineered the substrate specificity of these halogenases by mutating second-sphere residues. This work expands the toolbox of nucleotide halogenases and provides insights into the regulation mechanism of nucleotide specificity.
Topics: Substrate Specificity; Protein Engineering; Halogenation; Nucleotides; Deoxyguanine Nucleotides; Escherichia coli
PubMed: 38898020
DOI: 10.1038/s41467-024-49147-7 -
Science Advances Jun 2024Chloroplasts are the powerhouse of the plant cell, and their activity must be matched to plant growth to avoid photooxidative damage. We have identified a...
Chloroplasts are the powerhouse of the plant cell, and their activity must be matched to plant growth to avoid photooxidative damage. We have identified a posttranslational mechanism linking the eukaryotic target of rapamycin (TOR) kinase that promotes growth and the guanosine tetraphosphate (ppGpp) signaling pathway of prokaryotic origins that regulates chloroplast activity and photosynthesis in particular. We find that RelA SpoT homolog 3 (RSH3), a nuclear-encoded enzyme responsible for ppGpp biosynthesis, interacts directly with the TOR complex via a plant-specific amino-terminal region which is phosphorylated in a TOR-dependent manner. Down-regulating TOR activity causes a rapid increase in ppGpp synthesis in RSH3 overexpressors and reduces photosynthetic capacity in an RSH-dependent manner in wild-type plants. The TOR-RSH3 signaling axis therefore regulates the equilibrium between chloroplast activity and plant growth, setting a precedent for the regulation of organellar function by TOR.
Topics: Photosynthesis; Chloroplasts; Arabidopsis Proteins; Signal Transduction; Arabidopsis; Phosphorylation; Protein Processing, Post-Translational; Gene Expression Regulation, Plant; Guanosine Tetraphosphate; TOR Serine-Threonine Kinases; Phosphatidylinositol 3-Kinases
PubMed: 38896607
DOI: 10.1126/sciadv.adj3268 -
Frontiers in Endocrinology 2024Gonadotropin-releasing hormone (GnRH) is a key stimulator for gonadotropin secretion in the pituitary and its pivotal role in reproduction is well conserved in...
Differential involvement of cAMP/PKA-, PLC/PKC- and Ca/calmodulin-dependent pathways in GnRH-induced prolactin secretion and gene expression in grass carp pituitary cells.
Gonadotropin-releasing hormone (GnRH) is a key stimulator for gonadotropin secretion in the pituitary and its pivotal role in reproduction is well conserved in vertebrates. In fish models, GnRH can also induce prolactin (PRL) release, but little is known for the corresponding effect on PRL gene expression as well as the post-receptor signalling involved. Using grass carp as a model, the functional role of GnRH and its underlying signal transduction for PRL regulation were examined at the pituitary level. Using laser capture microdissection coupled with RT-PCR, GnRH receptor expression could be located in carp lactotrophs. In primary cell culture prepared from grass carp pituitaries, the native forms of GnRH, GnRH2 and GnRH3, as well as the GnRH agonist [D-Arg, Pro, NEt]-sGnRH were all effective in elevating PRL secretion, PRL mRNA level, PRL cell content and total production. In pituitary cells prepared from the rostral pars distalis, the region in the carp pituitary enriched with lactotrophs, GnRH not only increased cAMP synthesis with parallel CREB phosphorylation and nuclear translocation but also induced a rapid rise in cytosolic Ca by Ca influx via L-type voltage-sensitive Ca channel (VSCC) with subsequent CaM expression and NFAT dephosphorylation. In carp pituitary cells prepared from whole pituitaries, GnRH-induced PRL secretion was reduced/negated by inhibiting cAMP/PKA, PLC/PKC and Ca/CaM/CaMK-II pathways but not the signalling events via IP and CaN/NFAT. The corresponding effect on PRL mRNA expression, however, was blocked by inhibiting cAMP/PKA/CREB/CBP and Ca/CaM/CaN/NFAT signalling but not PLC/IP/PKC pathway. At the pituitary cell level, activation of cAMP/PKA pathway could also induce CaM expression and Ca influx via VSCC with parallel rises in PRL release and gene expression in a Ca/CaM-dependent manner. These findings, as a whole, suggest that the cAMP/PKA-, PLC/PKC- and Ca/CaM-dependent cascades are differentially involved in GnRH-induced PRL secretion and PRL transcript expression in carp lactotrophs. During the process, a functional crosstalk between the cAMP/PKA- and Ca/CaM-dependent pathways may occur with PRL release linked with CaMK-II and PKC activation and PRL gene transcription caused by nuclear action of CREB/CBP and CaN/NFAT signalling.
Topics: Animals; Carps; Gonadotropin-Releasing Hormone; Prolactin; Pituitary Gland; Protein Kinase C; Cyclic AMP-Dependent Protein Kinases; Calcium; Type C Phospholipases; Cyclic AMP; Signal Transduction; Calmodulin; Cells, Cultured; Gene Expression
PubMed: 38894746
DOI: 10.3389/fendo.2024.1399274