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PubMed2026

A yeast model of 5-oxoproline accumulation reveals a general toleration to 5-oxoproline.

5-oxoproline (5-OP) or pyroglutamic acid is an intermediate in the degradation arc of the glutathione cycle. It is metabolized into glutamate through the action of the 5-oxoprolinase enzyme, the only enzyme known to act on this metabolite. 5-OP has long been known to be relatively inert with a proposed role as an osomoprotectant. Recent studies on the 5-oxoprolinase enzyme in mammalian cells have, however, shown that knockdown or deletion of 5-oxoprolinase makes mice (and humans) prone to heart failure, an effect ascribed to oxidative stress caused by a twofold increase in 5-OP. To examine the consequences of 5-oxoproline accumulation more rigorously, we created a yeast model for 5-oxoproline accumulation. Using this model, we observed retardation of growth only when intracellular levels of 5-OP were increased 12- to 20-fold over normal levels. Performing an analysis of transcriptomic changes under these conditions, we observed a large number of genes were differentially regulated and while there was no unifying dysregulated pathway, there was an upregulation of various efflux pumps. Ultimately, modulating the expression of these genes by knockout or overexpression highlighted that many of the upregulated genes were involved in the cellular response to 5-OP accumulation. However, our results failed to show any significant oxidative stress response. In conclusion, our study suggests a need to reevaluate previous suppositions of the 5-OP induced oxidative stress response and proposes alternate mechanisms for this effect.

Pyrrolidonecarboxylic Acid↗
PubMed2026

Reprogrammed Komagataella phaffii for enhanced secretory expression of human lactoferrin.

Human lactoferrin (hLF) is a multifunctional glycoprotein of the transferrin family derived from milk and mucosal secretions, which exhibits antibacterial, anti-tumor, and immunomodulatory functions, and is an important component of infant formula. Conventional methods for lactoferrin expression are often inefficient, primarily due to inadequate protein synthesis capabilities and poor stability within microbial hosts. Herein, a Komagataella phaffii yeast strain capable of high-level secretory expression of hLF was constructed by reprogramming the endoplasmic reticulum (ER) and vacuole using CRISPR/Cas9 technology. A dual-expression cassette containing the AOX1 promoter, an α-secretion signal peptide, the hLF gene, and a terminator was integrated into three different sites of the K. phaffii genome. The stepwise strategy combining expansion of the ER membrane involved in protein synthesis with knockout of vacuolar proteases further enhanced hLF production. Subsequently, 0.1 g/L FeCl₃ was added to the medium to reduce the toxicity of hLF and improve its stability. After high-density cultivation of K. phaffii through optimization of cultivation conditions in shake flasks and a 5 L bioreactor, the secretory intact hLF titer reached 2214 mg/L, representing a 76.3-fold increase achieved through these engineering strategies. In addition, antibacterial experiments demonstrated that this secretory hLF had a significant inhibitory effect on Escherichia coli, Staphylococcus aureus, and yeast. Overall, the developed K. phaffii protein expression platform enabled efficient production of lactoferrin, demonstrating its potential for expressing other lactoproteins.

Lactoferrin↗
PubMed2025

Lipidomic profiling of mouse brain and human neuron cultures reveals a role for Mboat7 in mTOR-dependent neuronal migration.

Mutations in lipid regulator genes are a frequent cause of autism spectrum disorder, including those regulating phosphatidylinositol (PI) and phosphoinositide 3-kinase signaling. MBOAT7 encodes a key acyltransferase in PI synthesis and is mutated in an autism-related condition with neurodevelopmental delay and epilepsy. Using liquid chromatography-tandem mass spectrometry, we analyzed the PI-associated glycerolipidome in mice and humans during neurodevelopment and found dynamic regulation at times corresponding to neural apoptosis in the brains of Mboat7 knockout mice. Mboat7 function was necessary for polyunsaturated lipid synthesis and cortical neural migration, and loss resulted in massive accumulation of the precursor lysophosphatidylinositol and hyperactive mTOR signaling. Inhibiting mTOR signaling rescued migration defects. Our findings demonstrate roles for lipid remodeling during neurodevelopment and implicate lipid regulation in neuronal migration, revealing potential paths to treatment for MBOAT7 deficiency.

Animals↗
PubMed2022

DNA polymerase delta interacting protein 3 facilitates the activation and maintenance of DNA damage checkpoint in response to replication stress.

BACKGROUND: Replication stress response is crucial for the maintenance of a stable genome. POLDIP3 (DNA polymerase delta interacting protein 3) was initially identified as one of the DNA polymerase δ (Pol δ) interacting proteins almost 20 years ago. Using a variety of in vitro biochemical assays, we previously established that POLDIP3 is a key regulator of the enzymatic activity of Pol δ. However, the in vivo function of POLDIP3 in DNA replication and DNA damage response has been elusive. METHODS: We first generated POLDIP3 knockout (KO) cells using the CRISPR/Cas9 technology. We then investigated its biological functions in vivo using a variety of biochemical and cell biology assays. RESULTS: We showed that although the POLDIP3-KO cells manifest no pronounced defect in global DNA synthesis under nonstress conditions, they are sensitive to a variety of replication fork blockers. Intriguingly, we found that POLDIP3 plays a crucial role in the activation and maintenance of the DNA damage checkpoint in response to exogenous as well as endogenous replication stress. CONCLUSION: Our results indicate that when the DNA replication fork is blocked, POLDIP3 can be recruited to the stalled replication fork and functions to bridge the early DNA damage checkpoint response and the later replication fork repair/restart.

DNA Polymerase III↗
PubMed2026

MLL4 protects cardiomyocytes against ischemia-reperfusion injury through STAT3-mediated mitochondrial function.

Myocardial ischemia-reperfusion injury (MIRI) is an inevitable pathophysiological response during the revascularization process following myocardial ischemia. Despite its clinical significance, effective targeted therapies for MIRI remain an unmet medical need. Mixed-lineage leukemia 4 (MLL4), a member of the SET family of histone methyltransferases, exhibits particular methyltransferase action toward histone H3 lysine 4 (H3K4). This study establishes a protective role for MLL4 in MIRI pathogenesis. Utilizing cardiomyocyte-specific Mll4 knockout mice and an in vivo ischemia-reperfusion (I/R) model induced by left anterior descending coronary artery ligation, we observed significant upregulation of MLL4 expression in cardiac tissue following I/R. Genetic ablation of Mll4 in cardiomyocytes markedly exacerbated both acute and chronic phases of MIRI. In vitro, Mll4 knockdown in neonatal rat cardiomyocytes (NRCMs) amplified mitochondrial dysfunction and apoptosis under hypoxia/reoxygenation (H/R) conditions. Integrated analysis of Cleavage Under Targets and Tagmentation sequencing (CUT&Tag-seq) and RNA sequencing (RNA-seq) revealed that Mll4 deficiency induces a pronounced reduction in H3K4 monomethylation (H3K4me1) and histone H3 lysine 27 acetylation (H3K27ac) enrichment at the Stat3 genomic locus. Mechanistically, MLL4 functions as a transcriptional activator of Stat3 by depositing H3K4me1 and H3K27ac, thereby facilitating STAT3 transcription. This regulatory cascade ultimately governs STAT3-dependent mitochondrial homeostasis. Collectively, these findings identify MLL4 as a critical epigenetic regulator of MIRI and suggest its therapeutic targeting may offer a promising strategy for mitigating reperfusion injury.

Animals↗
PubMed2025

Interferon and TLR genes, but not endogenous bornavirus-like elements, limit BoDV1 replication after intracerebral infection.

Borna disease virus 1 (BoDV1) is a disease-causing agent in some livestock and, as has recently been shown, in humans. What constitutes a protective immune response to BoDV1 is unclear. Previous studies found that endogenous bornavirus-like nucleoprotein elements (EBLNs) present in mammalian genomes produce piRNAs antisense to BoDV1 nucleoprotein mRNAs. As a known function of piRNAs is to restrict transposons via RNA interference, it has been hypothesized that EBLN-derived piRNAs may restrict BoDV1. Here we used EBLN knockout (KO) and other KO mice to test genetic factors potentially involved in antiviral immunity to BoDV1. In previous reports, BoDV1 replication was higher in mice deficient in interferon gamma, and we confirmed a role for this cytokine in BoDV1 restriction at 12 weeks post infection using mice lacking its receptor. We show that BoDV1 replicates to higher levels in the brain of mice without Toll-like receptor 7 (TLR7), suggesting a role for this innate immune receptor in BoDV1 immunity. In contrast, mice lacking piRNA-producing EBLNs were no more susceptible to BoDV1 infection than wild-type under the infection conditions used here. We thus expand the genetic evidence implicating specific conventional immune pathways in BoDV1 control and conclude that EBLN-derived piRNA-guided antiviral silencing, if it occurs, is relatively less impactful in intracerebral infection of neonates.

Animals↗
PubMed2026

OsICL-associated metabolic reprogramming during dehydration in rice is regulated by ABA and modulated by ACC and its metabolites.

Drought coordinates hormonal, transcriptional, and metabolic reprogramming, but how abscisic acid (ABA) and 1-aminocyclopropane-1-carboxylic acid (ACC) jointly shape cereal dehydration responses remains unclear. We integrated hormone profiling, transcriptome and promoter analyses, synthetic promoter assays, and metabolite profiling in rice. ABA and ACC contents increased markedly in rice shoots under moderate soil water deficit. Combined ABA + ACC treatment showed larger absolute overlaps with dehydration-responsive genes than either ABA or ACC treatment alone in shoots; in roots, this pattern was observed for induced but not repressed genes. Promoters of dehydration- and ABA-inducible genes were enriched in ACGT-core motifs, including a CGTACG core preferentially embedded in ACGTACGT, designated the eXtended ACGT box (Xbox). Multimerised Xbox conferred transcriptional induction under soil water deficit and in response to ABA. OsICL was induced under soil water deficit and by ABA or ACC; in shoots, combined ABA + ACC treatment produced the highest mean transcript accumulation. OsICL overexpression and knockout lines showed altered organic-acid, sugar, and amino-acid profiles, particularly under soil water deficit, but several metabolites changed in the same direction in both line classes. These findings support an ABA-centred, ACC-modulated model of dehydration-responsive transcription and associate OsICL regulation with broader, condition-dependent changes in primary metabolism.

Oryza sativa↗
PubMed2025

Rice E3 ligase OsRFPH2-16 acts as a negative regulator to mediate the degradation of OsPIP1;1 under salt stress.

Soil salinity has a significant negative effect on rice productivity. We characterized the Oryza sativa RING Finger Protein H2-type-16 gene (OsRFPH2-16), which plays a negative role in response to salinity. The transcript levels of OsRFPH2-16 decreased under saline conditions. OsRFPH2-16 was expressed in the ER and tonoplasts of rice protoplasts. In addition, OsRFPH2-16 exhibited E3 ligase activity in an in vitro ubiquitination assay, whereas the mutant OsRFPH2-16C188A E3 ligase did not exhibit any activity. We constructed OsRFPH2-16-overexpressing (OX-2 and OX-4) and CRISPR/Cas9-mediated OsRFPH2-16-knockout (KO-4 and KO-16) plants and evaluated their salt responses. Under salt stress, OsRFPH2-16-knockout plants exhibited improved salt tolerance, characterized by low Na+ accumulation, high non-antioxidant content, and dynamic changes in the expression levels of Na+ transporter genes, compared with wild-type and OsRFPH2-16-overexpression plants. The aquaporin OsPIP1;1, an interacting partner, was identified using yeast two-hybridization, bimolecular fluorescence complementation, and pull-down assays. Degradation of OsPIP1;1 by the E3 ligase OsRFPH2-16 via the 26S proteasome system was confirmed through an in vitro degradation assay with the inhibitor MG132. These findings support that the E3 ligase functions as a negative regulator, leading to reduced Na+ accumulation in salt stress responses.

Oryza↗
PubMed2026

Big data analytics for CLEC5A dynamics based on single cell genomics and proteomics reveal its diverse functions in human diseases.

BACKGROUND: CLEC5A (C-type lectin domain family 5 member A) is an innate immune receptor implicated in inflammatory signaling, contributing to hyperinflammatory responses in infections and sterile inflammation. However, CLEC5A dynamics in human diseases remain to be identified. Here, we systematically characterized CLEC5A dynamics in humans across cells, tissues, and disease states, and to explore the functional significance of CLEC5A in macrophage activation based on single-cell genomics. METHODS: With multi-omics (scRNA-seq, proteomics and big data analytics), we analyzed extensive human transcriptomic datasets (>42,000 samples) to profile CLEC5A expression by cell type, tissue, and disease. Single-nucleus RNA-seq (snRNA-seq) from pediatric congenital heart disease and a virtual CLEC5A gene knockout were also performed to characterize CLEC5A dynamics in humans. RESULTS: CLEC5A is highly enriched in innate immune cells, particularly in macrophages and neutrophils. Baseline CLEC5A in most tissues is low, but it is markedly upregulated in inflammatory and infectious diseases. CLEC5A expression has sex-specific differences in certain organs. Single-cell analysis showed that CLEC5A can be considered novel marker of proinflammatory macrophages with elevated cytokine production, antigen presentation, and impaired phagocytosis. Virtual CLEC5A knockout analysis identified coordinated perturbation of immune-regulatory pathways and overlapping genes linking CLEC5A to macrophage activation networks. CONCLUSION: CLEC5A is predominantly expressed in myeloid cells and acts as a key amplifier of inflammation in human diseases. Our findings highlight CLEC5A as a potential biomarker and therapeutic target in myeloid-driven hyperinflammatory conditions, warranting further experimental and translational validation.

Humans↗
PubMed2025

Epitranscriptomic reprogramming in response to low CO2 stress and m6A engineering to enhance biomass production in Nannochloropsis oceanica.

N6-adenine methylation (m6A) as an epitranscriptomic mark is the most abundant modification in eukaryotic RNA and plays a dynamically regulated role. However, m6A dynamics, deposition and engineering in microalgae remain largely unknown. Here, in Nannochloropsis oceanica, the dynamic alterations and reprogramming in m6A RNA modifications after the shift from high to low CO2 conditions were first investigated using methylated RNA immunoprecipitation sequencing. The m6A peaks in N. oceanica were mainly enriched in 3'UTR. A positive association between m6A abundance and mRNA transcription of CO2-responsive genes was observed; moreover, N. oceanica cells adopted versatile strategies in a dynamic reprogramming of m6A in response to low CO2 stress. Secondly, knockout of two putative m6A methylases including NoMTA (NO04G02990) and NoMTB (NO07G02450) by genome editing induced methylation reprogramming, which was associated with expression changes of low-CO2 responsive genes such as carbon/nitrogen metabolism, and photorespiration genes that underlie reductions in growth and biomass. Lastly, m6A modification reprogramming was first engineered to increase low-CO2 stress tolerance and biomass productivity by the CRISPR/dCas13 system combined with MTA and NoMTB under low CO2 in N. oceanica. Therefore, these strides would pave the way for microalgal epigenetics and future industrial applications.

Microalgae↗
PubMed2026

Distinct Effects of Rap1 Subtype A GTPase Deficiency on the Male Mouse Heart.

This study utilized a genetically engineered mouse model deficient in the small GTPase Rap1A (knockout/Rap1A-null) to understand the biological role of Rap1A in the heart. We examined differential protein expression in the left ventricle of Rap1A-null versus wild-type control C57BL/6 male mice (~5 months) using proteomics (nanoLC-MS/MS quantitative analysis), and in the whole heart of aged male mice (~16 months) using MAL-DI-TOF/TOF mass spectrometry. Additionally, we used an experimental model of acute cardiovascular stress and assessed the impact on heart tissue histology, gene expression and mortality risk. Rap1A-deficient hearts showed reduced size and reduced heart and left ventricular weights. Significantly reduced gene expression of extracellular matrix collagen type I and collagen type III was present under baseline and cardiovascular stress conditions. Assessment of the proteomic profile identified a crucial role of Rap1A in promoting healthy ventricular myocardium, as its deficiency exhibited increased impact on cytoskeletal, mitochondrial, metabolic and contractile protein expression in young and aged mice. In young Rap1A-deficient mice, overrepresentation analysis revealed markers myosin heavy chain 7 (β-MHC) and alpha-actinin-2 (α-actinin-2) associated with cardiomyopathies, and upon cardiac stress, showed mortality risk compared to controls. Altogether, these findings provide important insights into the role of Rap1A in cardiac structure and remodeling under basal and stress conditions in male mice.

Animals↗
PubMed2026

Designing an optimized strategy for extracellular expression of recombinant human TNF-α in Escherichia coli.

Extracellular protein expression in Escherichia coli is an elegant solution that addresses the complex issue of protein misfolding while simultaneously simplifying downstream processing steps. Human TNF-α was chosen as the target protein for export since it is a therapeutically important cytokine. Different genomic knockouts were tested for the ability to sustain and enhance protein expression, and BW25113 Δ(elaA + cysW) knockout was found to give a sustained and high level of expression. To improve secretion, various tags were tested, and the MBP tag at the N-terminal end was found to give maximum enhancement in the export of hTNF-α. Even the linker peptide was found to play a critical role in export, with the Ek linker giving the highest extracellular secretion, while the intein sequence completely blocked export. The co-expression of pSecAB, which is involved in protein transport to the periplasm, was also found to be helpful in enhancing extracellular protein titers. Interestingly, pelB performed poorly as compared to the native signal sequence of MBP, which gave better results. Culture conditions were optimized, and it was observed that growing cells in TB medium at a temperature of 25 °C, coupled with a pulse of concentrated nutrients at 24 h, led to a very high extracellular accumulation of ∼1.3 g/L of MBP-hTNF-α in shake flask culture. The protein was purified and tested using L929 cells for bioactivity. Thus, a combination of genomic and bioprocess strategies allowed us to obtain high levels of soluble and active extracellular expression of hTNF-α, making this a very attractive strategy for protein production.

E. coli↗
PubMed2025

Cross-talk between NLRP3 and AIM2 inflammasomes in macrophage activation by LPS and titanium ions.

BACKGROUND: Periodontitis and peri-implantitis are chronic inflammatory diseases that contribute to tissue destruction and bone loss. Periodontitis is triggered by pathogenic bacteria, while peri-implantitis also involves metallic particles, which increase the inflammatory response. Both conditions are linked to the activation of inflammasomes, such as NLRP3 and AIM2, which facilitate the release of pro-inflammatory cytokines like IL-1β and IL-18 and induce pyroptosis. This study aims to investigate the activation of NLRP3 and AIM2 inflammasomes in macrophages exposed to bacterial and metallic components, as well as to explore the potential interplay between these two signaling pathways. METHODS: Human THP-1-derived macrophages were treated with bacterial lipopolysaccharide (LPS) and titanium ions to evaluate inflammasome activation. IL-1β secretion, ROS production, mitochondrial DNA release and pyroptosis were assessed. Additionally, macrophages deficient in NLRP3 and AIM2 were used to examine the roles of these inflammasomes in inflammatory responses. RESULTS: LPS and titanium ions synergistically activated NLRP3, resulting in increased IL-1β secretion, ROS production, and pyroptosis. Under these conditions, AIM2 was indirectly activated, as indicated by elevated mitochondrial DNA release. Notably, AIM2 expression was reduced in wild-type macrophages treated with LPS and titanium ions compared to LPS alone, however, in NLRP3-deficient cells, AIM2 expression was increased following LPS and titanium ions treatment. This upregulation of AIM2 in NLRP3-deficient cells was further reduced by ROS inhibition, which decreased mitochondrial DNA release. Additionally, NLRP3 knockout had a more pronounced effect on reducing IL-1β secretion and pyroptosis compared to AIM2 knockout, indicating a greater role of NLRP3 in these inflammatory responses. CONCLUSIONS: This study demonstrates that bacterial and metallic components drive the activation of both NLRP3 and AIM2 inflammasomes in macrophages, highlighting their roles in the inflammatory responses associated with periodontitis and peri-implantitis. The findings reveal a regulatory relationship between NLRP3 and AIM2, where the absence of one inflammasome can enhance the activity of the other. These results provide new insights into the mechanisms underlying inflammasome-mediated inflammation and suggest potential therapeutic targets for managing inflammatory diseases.

NLR Family, Pyrin Domain-Containing 3 Protein↗
PubMed2026

Transcriptional and phytohormonal regulation of positional ear development reveals yield strategies in maize.

Maize (Zea mays L.) is a vital global crop, contributing ∼37% of annual grain production. Enhancing yield per unit area is crucial for food security, yet research has primarily focused on single-ear traits, overlooking the regulation of double ears-a key determinant of prolificacy. While secondary ears drive yield variability under prolificacy-favoring conditions, the mechanisms governing ear formation across shoot positions remain poorly understood. Here, we performed high-resolution transcriptomic analysis of 66 samples from three ear types (primary, secondary and third) in maize inbred B73. We uncovered distinct hormonal developmental dynamics: strigolactone (SL) signaling genes, particularly SBP transcription factors, dominated in primary (I) ears, whereas ethylene-related genes (e.g., ZmEREB131, ZmACCO35) were enriched in third (III) ears. Functional validation confirmed that knockout of ZmEREB131 and ZmACCO35 accelerated development and elongated ears compared to wild-type, implicating ethylene (ETH) signaling in ear maturation arrest. Notably, SL inhibitor application synchronized primary and secondary ear development, boosting total yield by >20% without compromising primary ear performance. Our study elucidates the transcriptional networks underlying differential ear development and provides actionable strategies for yield improvement through targeted hormonal modulation. These findings advance the understanding of maize inflorescence biology and offer molecular tools for breeding high-yielding varieties.

RNA-seq↗
PubMed2026

Monitoring kinetic changes and restriction of influenza A virus RNA species during infection using a Flu-Stranded CRISPR platform.

UNLABELLED: Influenza A virus (IAV) generates three closely related RNA species: viral RNA (vRNA), complementary RNA (cRNA), and messenger RNA (mRNA), whose strand-specific quantification remains limited by sensitivity and quantitative dynamic range, particularly at low RNA abundance. Here, we developed Flu-Stranded CRISPR-Cas12a, a strand-specific detection platform integrating tagged reverse transcription, segment-specific PCR, and Cas12a collateral cleavage to support quantitative analysis of all three RNA species across a broad dynamic range. The assay enables reliable detection down to 102 copies per reaction, extending the lower quantitative boundary relative to both SYBR Green and TaqMan reverse transcription quantitative PCR (RT-qPCR) under matched conditions. Validated in infected cell lines, murine lung tissues, and clinical nasopharyngeal specimens, the platform enabled subtype-discriminating, strand-resolved detection, including samples near or below the quantitative range of SYBR Green RT-qPCR. Using finely resolved infection time-course analyses in NP and NA segments, we identified a reproducible early vRNA decline within the early post-infection phase. This decline was partially attenuated in RIG-I knockout A549 cells, while subsequent vRNA accumulation was enhanced, consistent with a modulatory rather than essential role for RIG-I in early viral RNA dynamics. Subcellular fractionation localized this decline to cytoplasmic incoming genomes. In contrast, importazole-mediated inhibition of nuclear import abolished vRNA recovery without affecting the early decline, indicating that nuclear entry functionally separates early genome reduction from subsequent productive replication. These findings establish Flu-Stranded CRISPR-Cas12a as a strand-resolved framework for monitoring IAV RNA dynamics and reveal an early window of genome vulnerability during cytoplasmic transit that shapes infection outcome. IMPORTANCE: The early fate of incoming influenza virus genomes remains unclear, limiting our understanding of how infection is established or aborted in host cells. We developed Flu-Stranded CRISPR-Cas12a, a strand-specific platform for sensitive and quantitative analysis of influenza viral RNA (vRNA), complementary RNA (cRNA), and messenger RNA (mRNA) across experimental and clinical samples. Using high-resolution time-course analysis, we identified a reproducible early decline in vRNA during the post-entry phase. Our data suggest that this early genome loss arises from multiple processes, with RIG-I acting as a modulatory factor rather than a primary driver. Subcellular fractionation localized this effect to cytoplasmic incoming genomes, whereas importin-β-mediated nuclear entry was required for subsequent vRNA recovery. These findings support a model of an early cytoplasmic phase of genome attrition that is distinct from replication and provide a framework for understanding early influenza RNA kinetics and for guiding strand-resolved diagnostics and antiviral evaluation.

CRISPR-Cas12a↗
PubMed2026

Host metadherin coordinates hepatic lipid metabolism and CD8+ T cell immunity to promote tumor progression.

Cancer progression is systemically influenced by distant organ dysfunction induced by primary tumors, yet how long-distance tumor-organ crosstalk regulates antitumor immunity remains unclear. Here, we identify host metadherin (MTDH) as a critical regulator of tumor-induced immunosuppression and metabolic reprogramming via tumor-liver interactions. Using Mtdh knockout mouse models, we show that concurrent MTDH loss in hepatocytes and CD8+ T cells enhances effector T cell function and suppresses tumor growth and metastasis. Mechanistically, tumor-derived extracellular vesicles and particles (EVPs) activate Kupffer cells to secrete tumor necrosis factor α (TNF-α) and TGF-β, which suppress hepatic PPARα-mediated lipid oxidation via nuclear factor κB (NF-κB) signaling. MTDH loss restores hepatic lipid catabolism, reduces systemic lipid levels, and promotes mitochondrial metabolic reprogramming in CD8+ T cells under lipid-reduced conditions, thereby boosting antitumor immunity. Genetic or pharmacological targeting of MTDH synergizes with anti-PD-1 therapy. These findings establish host MTDH as a key mediator of tumor-liver crosstalk through metabolic and immune interactions, driving systemic cancer progression.

CD8(+) T cells↗
PubMed2025

The SlWRKY39-SlZF61 module synergistically regulates SlGSTU42 to enhance low-temperature tolerance in tomato.

Low-temperature stress affects plant growth, and WRKY transcription factors alleviate such damage by regulating downstream genes. This study found that tomato SlWRKY39 significantly responds to low temperatures: its overexpression enhances seedling low-temperature tolerance by promoting ROS scavenging, while knockout exacerbates ROS accumulation and increases sensitivity to low temperatures. Transcriptome analysis indicated induction of glutathione metabolic pathway genes in slwrky39 plants under low-temperature stress. Y1H, EMSA, and Dual-LUC experiments confirmed that SlWRKY39 specifically binds to and activates the SlGSTU42 promoter; silencing SlGSTU42 attenuated the low-temperature tolerance conferred by SlWRKY39 overexpression, verifying that SlWRKY39 improves low-temperature tolerance via direct regulation of SlGSTU42. Additionally, SlZF61 interacts with SlWRKY39, enhancing its regulatory effect on SlGSTU42. SlZF61 overexpression strengthens low-temperature tolerance, while knockout increases sensitivity to low temperatures. In summary, under low-temperature stress, SlWRKY39 and SlZF61 are upregulated expression in tomato; SlWRKY39 binds to the SlGSTU42 promoter, and SlZF61 interacts with SlWRKY39 to form a protein complex, enhancing this binding. They synergistically activate SlGSTU42 transcription, thereby improving seedling low-temperature tolerance by scavenging ROS. This coordinated regulatory mechanism provides a new theoretical basis and practical insights for enhancing tomato low-temperature tolerance and ensuring stable production under low-temperature stress conditions.

Solanum lycopersicum↗
PubMed2026

Impact of NRSN2 deficiency on memory: Altered excitatory synaptic plasticity associated with reduced expression of NMDA receptor subunits and impaired LTP in the hippocampus.

Our earlier human studies identified NRSN2 (Neurensin-2), a neuronal-specific vesicular protein, as a candidate gene contributing to 20p13 microdeletion syndrome, yet the functional consequences of NRSN2 deficiency in the nervous system remain poorly understood. To explore the role of Nrsn2 in neurodevelopment and cognitive function, we utilized previously generated homozygous Nrsn2 knockout mice (Nrsn2-/-) and performed a series of behavioral, morphological, and electrophysiological analyses. Behaviorally, Nrsn2-/- mice exhibited mild locomotor impairment, as assessed by gait analysis at 4 and 8 weeks of age, as well as significant deficits in spatial learning and memory (Morris water maze) and fear memory (passive avoidance test) at 8 weeks. Morphometric analysis suggested no overt alterations in dendritic complexity or spine density in hippocampal CA1 pyramidal neurons or cerebellar Purkinje cells without developmental malformation. Electrophysiological recordings and immunoblotting analyses may reflect region-specific synaptic alterations. In the hippocampus, expression levels of the NMDA receptor subunits GluN1 and GluN2A were reduced at 4 weeks of age. Consistently, CA1 pyramidal neurons displayed decreased sEPSC frequency with unchanged amplitude under the conditions examined. In addition, an imbalance in hippocampal excitatory/inhibitory transmission was observed, as reflected by altered sEPSC frequency in the absence of changes in sIPSC frequency. In cerebellar Purkinje cells, GluA1-containing AMPA receptors were selectively downregulated, accompanied by reduced frequency and amplitude of sEPSCs and a selective decrease in sIPSC frequency, indicating both excitatory and inhibitory synaptic dysfunction in this region. Collectively, these findings indicate that Nrsn2 deficiency is accompanied by altered excitatory synaptic transmission and reduced long-term potentiation (LTP) at 8 weeks of age, despite preserved dendritic architecture as assessed by Golgi staining. These synaptic and plasticity deficits occur alongside the observed cognitive and motor impairments in Nrsn2⁻/⁻ mice. This study provides a descriptive phenotypic characterization of Nrsn2 deficiency and offers initial insights into the neurobiological role of NRSN2 and its contribution to neurodevelopment, learning, and memory.

Animals↗