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In coastal ecosystems, chemically rich species like gorgonians rely on specialized metabolites and symbiotic microbes for health and defense. In the Southwestern Atlantic, the elephant ear coral Phyllogorgia dilatata builds structurally complex forests and provides habitat for several species. Recent declines in cover have been linked to widespread disease, fouling, and necrosis. The loss of chemical defense due to anthropic perturbation has never been reported in the marine environment. We investigated whether pollution-driven stress could lead to a dysfunctional holobiont and impairment of its chemical defense. Using chromatography coupled to high-resolution mass spectrometry and molecular networking, we profiled secondary metabolites and used 16S rRNA gene amplicon sequencing to characterize microbial communities, relating these data to visual surveys of P. dilatata gorgonian forests. Defense compounds were found only in colonies far from pollution sources and correlated with bacteria associated with healthier environments. In contrast, pathogenic and sewage-associated bacteria dominated near the polluted site, where defenseless colonies of P. dilatata showed more disease and impaired health. Our results indicate that microbial pollution affects the capacity to modulate the microbiome through the use of infochemicals and leads to disruption of symbiosis and loss of chemical defense.
Inflammation and stroma remodeling regulate pancreatic ductal adenocarcinoma (PDAC), but how or if these cues are integrated at the molecular level remains unclear. Here, we identify a metabolic checkpoint that controls the stability of the collagen receptor DDR1, and subsequent tumorigenesis. We show that defective Col-I remodeling deprives PDAC cells of the high affinity DDR1 ligand, ¾Col-I, resulting in reduced ATP and activation of AMPK. AMPK phosphorylates DDR1 at T519, promoting its recognition by the E3 ubiquitin ligase adaptor FBXW2 and subsequent degradation. Importantly, this degradation pathway can be disabled by inflammatory signaling. Exposure to inflammatory cytokines induces methylation-dependent silencing of FBXW2, which establishes an inflammatory memory that preserves DDR1 stability, enabling sustained ligand-triggered receptor oligomerization and downstream NF-κB-NRF2 signaling even in restrictive stromal environments. Together, these findings identify regulated receptor turnover as a mechanism through which stromal architecture, metabolic state, and inflammatory memory are integrated to control PDAC progression.
RAS mutations are among the most common oncogenic drivers in human cancers, particularly in non-small cell lung cancer (NSCLC). Direct targeting of RAS proteins remains difficult due to the lack of suitable drug-binding pockets on their surfaces. LB42708 is a potent and selective farnesyltransferase (FTase) inhibitor that disrupts RAS farnesylation and downstream signaling. This study evaluates the anti-tumor effects of LB42708 in KRAS- and HRAS-mutant NSCLC cells, as well as gefitinib-resistant PC9 (PC9GR) cells. LB42708 significantly inhibits the proliferation, migration, invasion, stemness, and clonal growth of RAS-mutant NSCLC cells, while inducing apoptosis and cell cycle arrest. The inhibitory effects are further validated in patient-derived organoids and xenograft models. Mechanistically, LB42708 suppresses FTase activity, reduces RAS protein levels through proteasome-dependent degradation, and induces caspase-3–mediated degradation of the shared α-subunit of FTase and geranylgeranyltransferase-1 (GGTase-1). Combination treatment with LB42708 and the AKT inhibitor AZD5363 (capivasertib) produces synergistic anti-tumor activity in RAS-mutant NSCLC. Moreover, LB42708 enhances the sensitivity of PC9GR cells to gefitinib. Collectively, these findings demonstrate that LB42708, alone or in combination with AZD5363 or gefitinib, represents as a promising therapeutic candidate for NSCLC harboring RAS mutations or resistant to tyrosine kinase inhibitors (TKIs). Mutations in a family of genes called RAS are among the most common causes of cancer, especially non-small cell lung cancer (NSCLC). These mutations make cancer cells grow and spread uncontrollably. Unfortunately, RAS proteins are very hard to target directly with drugs because they lack good binding sites. In this study, we tested a compound called LB42708, which blocks an enzyme known as farnesyltransferase (FTase). This enzyme helps RAS proteins attach to cell membranes, a step that is essential for their cancer-promoting activity. By inhibiting FTase, LB42708 prevents RAS from functioning properly. We found that LB42708 strongly reduced the growth, movement, and stem cell–like behavior of lung cancer cells carrying KRAS or HRAS mutations. It also caused these cancer cells to stop dividing and undergo cell death. The same effects were observed in patient-derived tumor organoids and mouse models of lung cancer. Further experiments showed that LB42708 not only blocks FTase activity but also promotes the breakdown of RAS proteins through the cell’s natural protein degradation system, while also triggering caspase-3–mediated degradation of the FTase α-subunit, a key component required for RAS activation. When used together with another drug, AZD5363 (capivasertib), which inhibits the AKT signaling pathway, LB42708 produced even stronger anti-cancer effects. It also restored sensitivity to gefitinib, a drug that many lung cancers become resistant to. Overall, our results suggest that LB42708, either alone or in combination with other targeted therapies, could be a promising new treatment option for lung cancers with RAS mutations or drug resistance.
Mammalian palates are composed of the anterior hard palate and the posterior soft palate. However, the correlation of the genesis, pattern formation, and morphogenesis between the hard and soft palates remains elusive. In this study, we explicated the complicated palatal defects in Osr2-cre KI ;Ctnnb1 ex3f mice, in which canonical Wnt activity was persistent due to constitutively active β-catenin in the palatal mesenchyme. Osr2-cre KI ;Ctnnb1 ex3f palates displayed an ectopic mesenchymal condensation extending from the proximal-posterior area to the distal-anterior area, along with impaired osteogenesis and agenesis of soft palate. Immunohistochemistry showed the overlapping active canonical Wnt domain with the ectopic mesenchymal condensation, indicating that the condensation was induced by persistent canonical Wnt signaling. Wnt5a, a chemokine that induces posterior-anterior migration of palatal mesenchymal cells, was activated in the anterior and middle palatal mesenchyme of Osr2-cre KI ;Ctnnb1 ex3f mice. Exogenous supplementation of Wnt5a into wild-type (WT) palates recapitulated the mesenchymal condensation. These findings indicate that the persistent canonical Wnt signaling in the palatal mesenchyme extended Wnt5a expression, which enforced posterior mesenchymal migration toward the anterior to form the convoluted condensation, thereby impairing the genesis of the soft palate in Osr2-cre KI ;Ctnnb1 ex3f mice. Moreover, the medially osteogenic markers Sox9, Runx2, and Osx; the laterally Shh, Foxf1, and Fgf10; and another Wnt inhibitor, Sfrp2, were significantly reduced or even diminished in Osr2-cre KI ;Ctnnb1 ex3f palatal shelves. In contrast, the condensed Osr2-cre KI ;Ctnnb1 ex3f palatal mesenchyme displayed the medial markers Dlx5 and p-Smad1/5/8, along with the fibrosis/dermal markers ɑ-SMA and Tbx15. The Wnt and TGF-β/BMP inhibitors Ectodin and Noggin were also ectopically activated in the palatal epithelium overlying the condensed mesenchyme Osr2-cre KI ;Ctnnb1 ex3f mice. These findings indicate a transition of palatal mesenchymal cells from an osteogenic fate into fibrosis commitment, along with disrupted mediolateral patterning of the palatal shelves due to persistent canonical Wnt activity. Our study provides molecular clues that fine-tuning the mesenchymal canonical Wnt activity and Wnt5a-directed cell migration correlates with the morphogenesis of hard palates and the genesis of soft palates.
FOXL2 is a forkhead transcription factor (TF) essential for granulosa-cell identity and function, yet how post-translational modifications tune its activity remains incompletely understood. Here, we show that protein kinase C (PKC) phosphorylates FOXL2 in vitro. Two of the four phosphorylation sites, notably Ser101 and Ser107, map to the forkhead DNA-recognition helix. Phosphomimetic substitutions (S → D) at these positions (S101D/S107D) abolish binding to a consensus DNA sequence recognized by FOXL2 and luciferase reporter activation, whereas alanine substitutions are rather neutral. In HeLa cells, the S101D mutant and, to a lesser extent, S107A/S107D, relocalize at least partially to nucleoli and exhibit increased mobility consistent with reduced DNA engagement. This pattern was recapitulated in stably transduced KGN granulosa cells. RNA-seq of such KGN cells revealed that S101D and a C-terminal truncation (ΔC) induce a massive loss-of-function (LOF) relative to wild-type (WT) FOXL2. The LOF affects sets of genes involved in pathways central to granulosa physiology including ECM organization, cell migration/adhesion, and MAPK cascades, whereas S101A is largely WT-like. An analysis of the FOXL2 interactome in the transduced cells by mass spectrometry (MS) showed that S101D loses numerous interactions with TFs and chromatin remodelers, and Pol I/III regulators such as UBTF and TFIIIC components, while it gains other partners. By contrast, ΔC retains many of the protein-protein contacts of WT and preferentially loses ribosomal/TFIII interactions. Together, these data allow us to hypothesize that PKC-dependent phosphorylation within the FOXL2 DNA-recognition helix would underlie a rapid, reversible switch, weakening DNA binding, redirecting subnuclear partitioning, and rewiring protein-protein interactions, thereby reshaping FOXL2-dependent gene regulation in granulosa cells.
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Pancreatic ductal adenocarcinoma (PDAC) exhibits hyperactive mitochondrial metabolism, yet how this rewiring spatially restricts the availability of metabolites for oncogenic signaling and drives systemic metabolic dysregulation in PDAC remains unknown. Here, we identify enhanced mitochondrial α-ketoglutarate (α-KG) sequestration as a key metabolic vulnerability in PDAC. Using multi-omics, preclinical models, and clinical correlation analyses, we identified elevated mitochondrial metabolic gene expression in PDAC. Moreover, higher expression of dihydrolipoamide succinyltransferase (DLST) correlates with poorer PDAC prognosis, suggesting the role of mitochondrial α-KG sequestration in PDAC progression. Targeting mitochondrial respiration with the complex I inhibitor carboxyamidotriazole orotate (CTO) redirected α-KG flux from mitochondrial sequestration, and increased α-KG-dependent m6A demethylation of MYC mRNA and HIF-1α hydroxylation. Combining CTO or α-KG dehydrogenase complex inhibitor devimistat with an α-KG analog (dimethyl α-KG) amplified c-Myc/HIF-1α suppression. Consequently, prolonged CTO exposure downregulated multiple metabolic pathways (glycolysis, pentose phosphate pathway, fatty acid synthesis) regulated by c-Myc/HIF-1α, and significantly delayed PDAC progression in vitro and in vivo. Our work first identify a novel mechanism whereby mitochondrial metabolism drives systemic metabolic dysregulation in PDAC through the sequestration of α-KG, and establishes "redirecting α-KG flux from mitochondrial sequestration" as a strategy to disable PDAC's metabolic adaptability. The orotate salt form of carboxyamidotriazole effectively disrupts mitochondrial α-KG sequestration to suppresses PDAC growth at a dose equivalent to the clinically tested level.
The stereochemical recognition of the α-methyl group at the d-Ala-d-Ala terminus of peptidoglycan by penicillin-binding proteins (PBPs) has been implicated in shaping the evolutionary divergence of dd-peptidases. Here, we investigate how the β-lactam α-substituent identity influences the conformational dynamics of wild-type Pseudomonas aeruginosa PBP3 using molecular dynamics simulations of covalent acyl-enzyme complexes with CEFacyl (α-hydro) and its α-methyl derivative, MECacyl. Our analysis reveals that the α-methyl group in MEC-PBP3acyl is accommodated within a defined methyl pocket predominantly composed of conserved residues K297, S349, N351, and V333. Hydration network into the buried active site is disrupted in the MEC-PBP3acyl complex, which consequently results to the loss of a deacylation-competent geometry of water at K297 toward the β-lactam acyl carbon required for hydrolytic deactivation. Time-resolved analyses of the CEF-PBP3acyl simulation reveals that the contraction of the active site α-loop is associated with the coupling of water bridge networks that connects the α2 helix active site motif 294 STVK 297 to a distal salt bridge cluster-the "water sink" (R284 α1b, D288 loop, R504 β4, and D525 β5) which corroborates crystal structure evidence (PDB ID: 6R3X) [BelliniD., J. Mol. Biol.2019, 431, 3501-3519]. Pocket-based analyses show that the expansion of the methyl pocket into the STVK motif coincides with active site solvation. These dynamic observations are observed to be associated with the shifting salt bridge interactions of R504 β4 on the α-loop, which may rationalize resistance in R504 mutants. The steric bulk of the α-methyl group in MECacyl toward the K297 α2 side chain disables active site plasticity and consequently impairs the loop mobility required for the influx of water into the active site. These findings provide mechanistic molecular insights into how α-substituent chemistry modulates active site hydration dynamics in PBP3 and support the importance of α-methyl recognition in dd-peptidases. This work also establishes a structural framework for future studies of PBPs and β-lactam drug design relevant to antimicrobial resistance.
The human genome is dominated by noncoding sequences, most of which are poorly conserved across species. How genetic information is distributed between coding and noncoding regions remains a fundamental unresolved question. Using CRISPR saturation mutagenesis at base-pair resolution, we mapped the functional fitness landscape of the 10-kb human MYC locus with a near-PAMless, high-fidelity SpRY-Cas9. This unbiased interrogation revealed that the majority (67%) of functionally essential base-pairs in this locus are noncoding. Paradoxically, the phenotypic impact of noncoding sequences correlates inversely with evolutionary conservation, driven in part by rapidly diverging cis-regulatory DNA elements that remain functionally constrained in humans. Within this landscape, we identified an ultraconserved RNA element in the 3' untranslated region (UTR) that is indispensable for MYC-dependent cancer cells. Remarkably, steric-blocking antisense oligos targeting this RNA element selectively eliminate MYC-addicted cancer cells by suppressing MYC function without reducing MYC abundance. Mechanistically, this 3' UTR element promotes perinuclear localization of MYC mRNA and efficient nuclear import of the short-lived MYC protein, enabling its function as a nuclear transcription factor. Together, these findings highlight noncoding sequences as major carriers of functional genetic information, provide a comprehensive fitness map of the MYC locus, and uncover a therapeutically actionable RNA element that disables MYC-driven cancer.
In response to the urgent need for effective antiviral agents, this study explores the potential of vacuoles isolated from yeast in combating non-enveloped tailed viruses, using the T4 virus as a model. Concentration- and time-dependent assays revealed that vacuoles significantly inhibit T4 virus infectivity, achieving over 80% inhibition at 250 μg/mL. Morphological analysis via Bio-TEM imaging unveiled structural changes in the T4 virus after vacuole treatment, including separation of the capsid and tail, leading to impaired virion integrity. Optimization of vacuole storage conditions, particularly storing vacuoles in a pellet state, enhanced their antiviral efficiency. Characterization studies revealed structural modifications in vacuoles stored in the pellet state, such as increased particle size and changes in surface charge properties, potentially facilitating increased interaction with virion particles. These findings underline the promising potential of yeast-derived vacuoles as eco-friendly and effective antiviral agents against non-enveloped tailed viruses and provide insights into their mechanism of action. Further research is needed to elucidate molecular-level interactions and evaluate efficiency against other non-enveloped viruses. By offering novel insights into the antiviral potential of vacuoles, this study contributes to the development of eco-friendly antiviral strategies to address global health challenges.IMPORTANCENon-enveloped viruses remain difficult to inactivate without harsh chemicals or heat. This study introduces yeast-derived vacuoles as a biologically based antiviral platform that disables a model non-enveloped bacteriophage (T4) with >80% inhibition at 250 μg/mL. Bio‑TEM reveals capsid-tail disassembly after vacuole exposure, linking macroscopic loss of infectivity to a defined structural mechanism. Storage engineering-maintaining vacuoles in pellet form-enhances efficacy and correlates with increased particle size and altered surface charge, suggesting tunable physicochemical interactions with virions. These results establish vacuoles as scalable, eco-friendly antiviral agents and provide design rules (dose, contact time, storage state, surface properties) for optimizing activity. Because the approach targets virion integrity rather than specific proteins, it may generalize across non-enveloped viruses, motivating molecular-level studies and translational testing. The work broadens the antiviral toolkit by leveraging a safe, low-cost cellular organelle.
The aging epigenome is shaped by three mechanistically distinct histone post-translational modifications-acetylation, lactylation, and glycation-each driven by a different metabolic flux: mitochondrial oxidative phosphorylation, glycolytic lactate production, and reactive carbonyl stress, respectively. Understanding their interplay is central to a molecular physiology of epigenetic aging. This mini review synthesizes current evidence on the mechanisms of histone acetylation, lactylation, and glycation in aging; their crosstalk and convergence on shared regulatory nodes; and their modulation by environmental, nutritional, and behavioral factors. Key controversies and research gaps are critically appraised. NAD + decline in aging disables the sirtuin deacetylase family, dysregulating the histone acetylation landscape and impairing autophagy, mitochondrial biogenesis, and DNA repair. Histone lactylation, written by p300 at H3K18 and related lysine residues, is context-dependent: physiological pulses during exercise and sleep are adaptive, while chronic accumulation in diabetic microglia drives neuroinflammation via TLR4/NF-κB, and excess in tumor cells enables senescence bypass. Histone glycation by methylglyoxal irreversibly displaces regulatory marks and inactivates sirtuin proteins; pharmacological induction of glyoxalase I and glycation-lowering interventions reduce this burden and extend healthspan. These three axes may converge on a unified metabolic-epigenetic collapse that we propose constitutes the cellular basis of an 'aging' metabolic memory. Lactylation erasers remain uncharacterized; the pro-versus anti-senescence duality of H3K18la is unresolved; and genome-wide histone glycation mapping in human tissues is absent. Combinatorial interventions targeting NAD + restoration, modulation of lactylation, and reduction of carbonyl stress offer the most evidence-based approach to slowing metabolic-epigenetic aging.
Decades of research have uncovered the complex signaling network downstream of the opioid receptors and suggested how this signaling could be modulated to improve opioid therapy. In our study, we have found that heat shock protein 90 (Hsp90) regulates downstream opioid signaling oppositely in the brain vs the spinal cord. In the spinal cord, we have found that Hsp90 inhibition enables antinociceptive signaling and disables pronociceptive signaling to enhance opioid pain relief and reduce side effects. We have now extended this study to analyze the contribution of protein kinase C (PKC) to the opioid signaling cascade. We used the Hsp90 inhibitor 17-AAG along with a PKC activator or inhibitor (Go6983) delivered into the spinal cords of male and female CD-1 mice to show that pan-PKC signaling contributes to the enhanced opioid antinociception observed in tail flick and postsurgical pain models. We used Western blot and immunohistochemistry to observe increased pan-PKC phosphorylation across calcitonin gene-related peptide (CGRP) and IB4 nociceptors in the spinal dorsal horn. We then used selective siRNA to identify PKCβ as the active isoform and further found PKCβ to be selectively activated in CGRP neurons by Hsp90 inhibition and morphine combined. Finally, we used cell-type-selective Clustered Regularly Interspaced Short Palindromic Repeats (CRISPR) to knock down PKCβ in CGRP neurons and showed that this specific isoform in these specific cells was necessary for enhanced opioid antinociception after Hsp90 inhibition.Together, these studies further uncover the novel Hsp90-regulated opioid signaling cascade and suggest how Hsp90 inhibitors could be used to improve opioid therapy by increasing analgesic efficacy and decreasing side effects.
Pancreatic cancer (PC) remains a highly lethal malignancy with limited treatment options and poor survival. Targeting DNA damage response (DDR) pathways has emerged as a promising therapeutic strategy, particularly the ATR-CHK1 and ATM-CHK2 axes. Preclinical studies demonstrate that ATR inhibition disrupts replication stress tolerance, impairs homologous recombination, and disables checkpoint control, enhancing cytotoxicity from standard therapies including gemcitabine, FOLFIRINOX, fluoropyrimidines, and radiotherapy. Synergistic effects have also been observed with other DDR-targeted agents, such as PARP and WEE1 inhibitors. Genomic contexts, including ATM deficiency, ARID1A alterations, and oncogene-driven replication stress, refine therapeutic sensitivity, supporting precision patient stratification. Early-phase clinical trials of ATR inhibitors (ART0380, AZD6738, BBI-355) alone or in combination show promising safety, tolerability, and preliminary efficacy. In this review, we summarize current literature on targeting the ATM-CHK2 and ATR-CHK1 pathways in PC, highlighting preclinical evidence, clinical developments, and strategies for biomarker-driven, precision oncology approaches.
Nitric oxide synthase 2 (NOS2) and cyclooxygenase 2 (COX2) lie at a critical intersection between inflammation, metabolism, and oncogenic signaling, where they cooperatively promote and establish a Nitric Oxide (NO)-driven Warburg phenotype in advanced cancers. Early work in macrophages established NOS2-derived NO as both a signaling molecule and metabolic stressor that inhibits oxidative phosphorylation (OXPHOS) by targeting iron-sulfur enzymes and respiratory complexes, forcing neighboring cells to rewire metabolism. In human tumors, sustained NOS2 expression in cancer cells and tumor-associated macrophages (TAMs) enforces a Warburg-like state characterized by high glycolytic flux, glutamine dependence, and enhanced NADPH production, supporting proliferation, biosynthesis, and resistance to oxidative stress. At nitrosative-signaling concentrations (≈100-500 nM), NO breaks carbon entry into the TCA cycle at aconitase and pyruvate dehydrogenase, progressively disables dehydrogenase complexes containing dihydrolipoamide dehydrogenase (DLD) and electron-transport complexes (ETCs), and activates hypoxia-inducible factor 1-alpha (HIF-1), phosphoinositide 3-kinase (PI3K)/protein kinase B (Akt), extracellular signal-regulated kinase (ERK)/pyruvate kinase M2 (PKM2)/c-Myc signaling axis, nuclear factor erythroid 2-related factor 2 (Nrf2), and transforming growth factor Beta (TGF-β)/SMAD pathways. These biochemical and signaling effects convert transient glycolytic adaptation into chemically enforced dependency, further stabilized by metabolite-driven inhibition of ten-eleven translocation (TET) and Jumonji demethylases, creating an "epigenetic lock" that maintains oncogenic transcriptional programs. NOS2 and COX2 form a reciprocal feed-forward circuit in which NO, prostaglandin E2 (PGE2), interleukin (IL)-6, and IL-8 reinforce one another, driving tumor-promoting inflammation, immunosuppression, angiogenesis, and metastasis while depleting nutrients and acidifying the tumor interstitial fluid. Spatially, NOS2/COX2 niches at the tumor-stroma interface and within immune deserts generate gradients of NO, PGE2, oxygen, and metabolites that partition tumors into microdomains with distinct metabolic states, immune composition, and therapeutic vulnerabilities. Integrating these insights with Hanahan's updated hallmarks of cancer, we propose that NOS2-derived NO functions as a node synchronizing deregulated energetics, inflammation, immune evasion, plasticity, and therapy resistance within the tumor microenvironment (TME). Targeting the NOS2-COX2 axis and its downstream NO-iron-epigenetic circuitry may therefore disrupt multiple hallmarks and reveal combinatorial strategies to exploit NO-induced metabolic liabilities in cancer.
In recent years, H5 subtype highly pathogenic avian influenza viruses (HPAIVs), especially clade 2.3.4.4b, have posed a global threat to poultry, cattle, and public health. Bioinformatics analysis of H5 subtype AIVs from 2000 to 2023 revealed a progressive increase in the PA-X N193S mutation, which became predominant in both avian and mammalian isolates of clade 2.3.4.4b. Using reverse genetics, we generated viruses with PA-X 193N (rWT) and 193S (rWT-N193S). The PA-X N193S mutation significantly inhibited viral polymerase activity while enhancing host shutoff. In vitro and vivo, rWT-N193S showed attenuated replication in avian and mammalian cells, reduced pathogenicity in mice, and suppressed cytokine storms. However, it enhanced uptake by dendritic cells (DCs), impairing DC maturation, activation, cytokine secretion, and CD4+ T cell proliferation. In murine nasal mucosal experiments, the PA-X N193S mutation reduced CCL5 expression, altered DC recruitment, and suppressed IL-17/MAPK signalling. These findings reveal a viral trade-off: the mutation attenuates epithelial replication and immunopathology but enhances DC uptake and disables mucosal immune functions, a strategy that likely contributed to the global predominance of PA-X N193S mutation in epidemic H5 subtype viruses.
Traumatic brain injury (TBI) disproportionately kills and disables older adults, yet the biology driving this vulnerability remains unresolved. In this issue of the JCI, Lu et al. combined single-cell transcriptomics, metabolomics, and chromatin profiling in mice, validated in human TBI tissue, to define an age-dependent microglial dichotomy. They report that an NLRP3+/IL-1β-linked state dominates the aged brain, while a Lysozyme+/Lyz2+ state predominates in the young. Microglia-targeted perturbation of NLRP3 and ELF1 each shifted the balance and improved survival in mouse models of TBI, and the repurposed drug Imeglimin improved outcomes in these models, confirming that this pathway is druggable. By connecting NLRP3 inflammasome dominance, ELF1-driven transcription, and glycolytic reprogramming to the loss of a protective Lyz2+ response, this work converts age from a clinical risk factor to a set of druggable microglial targets.
The relay domain of the myosin molecular motor communicates with the nucleotide binding site of the molecule, the actin-binding region, and the converter domain. Interactions between the relay and converter domains are critical for the converter to elicit movement of the lever arm, which yields the molecule's power stroke. An invariant tryptophan relay residue at the converter interface is flanked by two poorly conserved amino acids. Here we utilize mutant versions of the Drosophila melanogaster muscle myosin heavy chain to probe the function of these variable relay residues, residues 509 and 511. We replaced either or both poorly-conserved residues within an embryonic myosin isoform with those of the indirect flight muscle isoform. All such replacements eliminate in vitro actin motility, suggesting abnormal communication between the relay and converter domains that disables the power stroke. Interestingly, we found that the variations at residues 509 and 511 differentially disrupt both myosin ATPase activity and indirect flight muscle ultrastructure, with the double mutant showing the most severe effect upon ATPase activity and the least severe effect on emergent adult ultrastructure. Isoform-specific interactions may be implicated in these differential effects, as our molecular modeling at two stages of the mechanochemical cycle defined differences in contacts between the embryonic, flight muscle and chimeric 509 and 511 relay residues with a key residue in the converter domain. Overall, our studies show that two poorly conserved amino acid residues at the relay-converter interface are important to isoform-specific function of myosin and to the structural integrity of muscle.
Root-knot nematodes (Meloidogyne spp.) secrete effectors that suppress plant immunity; however, the mechanisms by which they counteract specific defense enzymes, such as chitinases, remain unclear. In this study, we demonstrate that the Meloidogyne incognita effector Minc10750 directly targets the catalytic domain of plant chitinases (Chi), serving as a critical determinant of virulence. The expression of Minc10750 is upregulated in the subventral esophageal glands during early infection. Its binding to the glycosyl hydrolase 19 domain of chitinases is strictly dependent on effector N-glycosylation. A mutation at the asparagine glycosylation site (Minc10750-Mu3) abolishes this modification, impairs its nuclear accumulation, and disrupts the interaction. Mechanistically, Minc10750 promotes the proteasome-dependent destabilization of Chi proteins, thereby suppressing Chi-triggered immunity, including mitogen‑activated protein kinase (MAPK) activation and reactive oxygen species burst. Consistently, Chi mutants exhibit enhanced susceptibility to nematodes, whereas Chi overexpression confers resistance. Transcriptome analysis further reveals that the Chi-mediated expression of defense-related transcription factors is compromised in Minc10750 transgenic plants. Our findings elucidate a mechanism by which a glycosylated nematode effector disables a core component of basal immunity, thereby providing a potential target for the engineering of nematode-resistant crops.
Surgical navigation depends on precise image-to-patient registration, yet line-of-sight issues on the tracker, anatomy deformation, and occlusion from instruments and the surrounding environment degrade accuracy and lead to failing scenarios. We target a tracker-free, robust, and explainable vision-based framework for complex operative scenes. We fuse accurate depth estimation with dense 2D point tracking to recover temporally consistent 3D surface motion from surgical video, continuously updating image-to-patient registration. We also present the registration error detection module where we evaluate tracking quality, motion consistency, and 3D motion agreement to rapidly detect and attribute errors (e.g., occlusion, or drift). If an error is detected, the module also disables the mesh overlay. Across three phantom scenarios (tool-occluded, layer-occluded, and deformed), our method improves target registration accuracy and robustness compared to the traditional method (ICP) and the learning-based baseline (PREDATOR), particularly under partial occlusion and moderate non-rigid manipulation. On the live-porcine sequence, our proposed method delivers higher accuracy and approximately 20 × faster runtime than baselines, indicating feasibility for a real-time application. Beyond accuracy, our approach enables early detection of failure modes, guiding appropriate user intervention. Our proposed method, coupled with explainable error detection, maintains registration while reducing reliance on external trackers, contributing to the ongoing effort to build trustworthy, resilient image-guided surgery.
Tumor immune escape is a major barrier to durable cancer immunotherapy, as advanced malignancies create a tumor microenvironment (TME) that preferentially exhausts and disables T cell responses. While most approved cell therapies are T cell-based, this limitation motivates the exploration of an alternative effector cell platform. Natural killer (NK) cells, innate cytotoxic lymphocytes capable of antigen-independent recognition and killing, offer a compelling foundation for next-generation therapies with an improved safety profile. In this review, we first outline the cellular, molecular, and metabolic features of the immunosuppressive TME that restrict cytotoxic lymphocyte function, emphasizing mechanisms that limit immune cell-mediated responses. We then summarize key aspects of NK cell biology that can circumvent these barriers and critically evaluate current NK-based strategies, including engineered chimeric antigen receptor (CAR)-NK products and metabolic and trafficking interventions. Finally, we highlight emerging in vivo viral and mRNA/lipid nanoparticle platforms for CAR-NK generation and their potential to enhance scalability and therapeutic durability.