1.The effects of galangin on the apoptosis and autophagy of gastric cancer NCI-N87 cells through regulating the AMPK/mTOR/ULK1 signaling pathway
GUO Fang ; CHEN Wei ; LIU Meng ; ZOU Yanli ; TIAN Xia
Chinese Journal of Cancer Biotherapy 2026;33(1):59-65
[摘 要] 目的:探讨高良姜素(Gal)调控AMPK/mTOR/ULK1信号通路对胃癌细胞凋亡和自噬的影响及其机制。方法:将胃癌NCI-N87细胞分为对照组、多索吗啡(DM)组、Gal低剂量(Gal-L)组、Gal高剂量(Gal-H)组、Gal-H + DM组。采用MTT法、流式细胞术、划痕愈合实验和Transwell实验分别检测各组细胞的增殖、凋亡、迁移和侵袭能力,WB法检测PCNA、C-caspase-3、免疫逃逸相关蛋白(B7H1)、EMT和AMPK/mTOR/ULK1信号通路蛋白的表达水平。建立裸鼠NCI-N87细胞移植瘤模型,观察Gal和5-FU对移植瘤的抑制效果。结果:与对照组比较,DM组NCI-N87细胞增殖活性、划痕愈合率和侵袭细胞数、N-cadherin、vimentin、PCNA、B7H1、p62和p-mTOR/mTOR蛋白表达均显著升高(均P < 0.05),细胞凋亡率、C-caspase-3、E-cadherin、LC3Ⅱ/LC3Ⅰ、p-AMPK/AMPK和p-ULK1/ULK1蛋白表达均显著降低(均P < 0.05);Gal-L组和Gal-H组NCI-N87细胞的增殖活性、划痕愈合率和侵袭细胞数、N-cadherin、vimentin、PCNA、B7H1、p62和p-mTOR/mTOR蛋白表达均显著降低(均P < 0.05),细胞凋亡率、C-caspase-3、E-cadherin、LC3Ⅱ/LC3Ⅰ、p-AMPK/AMPK和p-ULK1/ULK1蛋白表达均显著升高(均P < 0.05);DM可部分逆转Gal对NCI-N87细胞恶性生物学行为的抑制作用(P < 0.05);与对照组比较,Gal组和5-FU组裸鼠移植瘤体积和质量均显著降低,肿瘤组织细胞凋亡率显著升高(P < 0.05)。结论:Gal可促进胃癌NCI-N87细胞自噬和凋亡,抑制其增殖、迁移和侵袭,可能与激活AMPK/mTOR/ULK1信号通路有关。
2.Effect and Mechanism of Exogenous NO in Secondary Metabolism in Scutellaria baicalensis
Kai ZHAO ; Wei MA ; Weili LIU ; Zhihong LOU ; Xiangcai MENG
Chinese Journal of Experimental Traditional Medical Formulae 2026;32(1):250-261
ObjectiveTo investigate the effects of exogenous nitric oxide (NO) on the accumulation and quality formation mechanism of flavonoids in Scutellariae Radix. MethodsFresh roots of Scutellaria baicalensis were treated with sodium nitroprusside (SNP) solutions at concentrations of 0.0, 7.5, and 20 mmol·L-1, respectively. Kits and supporting reaction systems were used to determine the following indicators of samples in each group, including (1) reactive oxygen species: changes in the content of nitric oxide (NO), superoxide anion (O
3.Modified Yacoub technique for patients with aortic root aneurysm
Hongjia MA ; Qianlei LANG ; Chaoyi QIN ; Hong QIAN ; Zhenghua XIAO ; Wei MENG
Chinese Journal of Clinical Thoracic and Cardiovascular Surgery 2026;33(04):611-614
Objective To evaluate the feasibility and safety of Remodeling+Ring (modified Yacoub) for patients with aortic root aneurysm. Methods The clinical data of patients who underwent modified Yacoub surgery at West China Hospital of Sichuan University from July 2020 to May 2023 were retrospectively analyzed. Results Four male patients were enrolled, with an average age of (47.3±10.3) years and body surface area of (1.9±0.2) m2. One patient had bicuspid aortic valve. Aortic valve regurgitation was mild in three patients and moderate in one patient. Preoperative New York Heart Association (NYHA) heart function was gradeⅠin one patient and gradeⅡin three patients. The maximum diameter of the aortic sinus was (59.3±8.1) mm. All four patients recovered and were discharged without a second thoracotomy. No postoperative complications such as brain injury, infection, respiratory failure or renal insufficiency occurred. During the follow-up of (17.0±13.1) months, two patients showed no regurgitation of the aortic valve, two patients exhibited mild regurgitation. Three patients had a heart function of gradeⅠ and one patient of gradeⅡ. Conclusion Modified Yacoub technique is safe and effective for patients with aortic root aneurysm.
4.Evolving Paradigms in IgA Nephropathy Management: from Traditional Risk Stratification to Biomarker-Driven Precision Medicine
Dingding WANG ; Meng YAO ; Xiao LIU ; Qingxian ZHAI ; Qiong WEN ; Wei CHEN
Medical Journal of Peking Union Medical College Hospital 2026;17(2):317-323
IgA nephropathy (IgAN) is the most common primary glomerulonephritis worldwide and a major cause of chronic kidney disease and kidney failure. IgAN exhibits marked heterogeneity in clinical presentation, histopathology, and pathogenic mechanisms, contributing to variable treatment responses and prognosisamong patients. Precise risk assessment and individualized intervention are therefore of critical importance. This review systematically traces the evolution of IgAN management from traditional risk stratification toward biomarker-driven precision medicine. We first review the clinical utility and limitations of established risk stratification tools, including the KDIGO guidelines, the Oxford MEST-C classification, and the International IgAN Prediction Tool. We then discuss emerging biomarkers closely linked to disease pathogenesis, including galactose-deficient IgA1 (Gd-IgA1), anti-Gd-IgA1 autoantibodies, B cell activating factor (BAFF), a proliferation-inducing ligand (APRIL), and complement components, as well as the targeted therapies they have informed. In addition, urinary biomarkers and multi-omics approaches show promise for dynamic disease monitoring and individualized risk stratification.
5.Regulatory Effect of Danhe Granules on Oxidative Stress in Rats with Mixed Hyperlipidemia
Jingke MENG ; Susu LIU ; Pan GAO ; Mingjiao JIA ; Bochao JIA ; Qingzheng XING ; Yulong CHEN ; Wei WANG ; Xinlou CHAI
Chinese Journal of Experimental Traditional Medical Formulae 2026;32(10):112-122
ObjectiveTo investigate the therapeutic mechanism of Danhe granules in treating mixed hyperlipidemia based on network pharmacology, as well as animal and cell experiments. MethodsThe active compounds and targets of Danhe granules were screened using the Traditional Chinese Medicine Systems Pharmacology Database and Analysis Platform (TCMSP) and the Encyclopedia of Traditional Chinese Medicine (ETCM). Related targets for mixed hyperlipidemia were obtained from the GeneCards database. The intersecting targets were subjected to Gene Ontology (GO) functional annotation and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analyses. A high-fat model was established in human hepatocellular carcinoma cells (HepG2) induced by palmitic acid (PA), followed by intervention with Danhe granules to assess intracellular lipid accumulation and oxidative stress levels. A mixed hyperlipidemia rat model was also established and divided into low-, medium-, and high-dose Danhe granules groups (1.134, 2.268, and 4.536 g·kg-1, respectively), as well as a positive control group treated with pravastatin sodium (4.020 mg·kg-1). After eight weeks of intervention, serum lipid levels, inflammatory factors, oxidative stress indices, and the expression of key hepatic lipid metabolism-related proteins were determined. ResultsNetwork pharmacology identified 93 intersecting targets between Danhe granules and mixed hyperlipidemia, with peroxisome proliferator-activated receptor gamma (PPARG), peroxisome proliferator-activated receptor alpha (PPARA), tumor necrosis factor (TNF), interleukin-6 (IL-6), and IL-1B among the key nodes. The PPAR signaling pathway, AGE/RAGE signaling pathway, lipid metabolism, atherosclerosis and non-alcoholic fatty liver disease (NAFLD) were among the most significantly enriched pathways. Cellular experiments demonstrated that Danhe granules significantly reduced reactive oxygen species (ROS) and malondialdehyde (MDA) levels while increasing catalase (CAT) activity (P<0.05), thereby alleviating intracellular lipid accumulation and triglyceride (TG) content in HepG2. In animal experiments, Danhe granules markedly decreased serum total cholesterol (TC), TG, and low-density lipoprotein cholesterol (LDL-C) levels (P<0.05), reduced hepatic MDA levels, and elevated superoxide dismutase (SOD) and CAT levels. Histological analysis showed alleviation of hepatic steatosis, upregulation of hepatic PPARA and lipoprotein lipase (LPL) expressions, and downregulation of sterol regulatory element-binding protein 1 (SREBP1) expression (P<0.05, P<0.01). ConclusionDanhe granules improve lipid metabolism disorders in mixed hyperlipidemia by reducing MDA levels, enhancing SOD and CAT activities, scavenging excessive ROS, inhibiting oxidative stress, and mitigating liver injury. The underlying mechanism may involve the upregulation of PPARA and LPL and the suppression of SREBP1 expression.
6.Regulatory Effect of Danhe Granules on Oxidative Stress in Rats with Mixed Hyperlipidemia
Jingke MENG ; Susu LIU ; Pan GAO ; Mingjiao JIA ; Bochao JIA ; Qingzheng XING ; Yulong CHEN ; Wei WANG ; Xinlou CHAI
Chinese Journal of Experimental Traditional Medical Formulae 2026;32(10):112-122
ObjectiveTo investigate the therapeutic mechanism of Danhe granules in treating mixed hyperlipidemia based on network pharmacology, as well as animal and cell experiments. MethodsThe active compounds and targets of Danhe granules were screened using the Traditional Chinese Medicine Systems Pharmacology Database and Analysis Platform (TCMSP) and the Encyclopedia of Traditional Chinese Medicine (ETCM). Related targets for mixed hyperlipidemia were obtained from the GeneCards database. The intersecting targets were subjected to Gene Ontology (GO) functional annotation and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analyses. A high-fat model was established in human hepatocellular carcinoma cells (HepG2) induced by palmitic acid (PA), followed by intervention with Danhe granules to assess intracellular lipid accumulation and oxidative stress levels. A mixed hyperlipidemia rat model was also established and divided into low-, medium-, and high-dose Danhe granules groups (1.134, 2.268, and 4.536 g·kg-1, respectively), as well as a positive control group treated with pravastatin sodium (4.020 mg·kg-1). After eight weeks of intervention, serum lipid levels, inflammatory factors, oxidative stress indices, and the expression of key hepatic lipid metabolism-related proteins were determined. ResultsNetwork pharmacology identified 93 intersecting targets between Danhe granules and mixed hyperlipidemia, with peroxisome proliferator-activated receptor gamma (PPARG), peroxisome proliferator-activated receptor alpha (PPARA), tumor necrosis factor (TNF), interleukin-6 (IL-6), and IL-1B among the key nodes. The PPAR signaling pathway, AGE/RAGE signaling pathway, lipid metabolism, atherosclerosis and non-alcoholic fatty liver disease (NAFLD) were among the most significantly enriched pathways. Cellular experiments demonstrated that Danhe granules significantly reduced reactive oxygen species (ROS) and malondialdehyde (MDA) levels while increasing catalase (CAT) activity (P<0.05), thereby alleviating intracellular lipid accumulation and triglyceride (TG) content in HepG2. In animal experiments, Danhe granules markedly decreased serum total cholesterol (TC), TG, and low-density lipoprotein cholesterol (LDL-C) levels (P<0.05), reduced hepatic MDA levels, and elevated superoxide dismutase (SOD) and CAT levels. Histological analysis showed alleviation of hepatic steatosis, upregulation of hepatic PPARA and lipoprotein lipase (LPL) expressions, and downregulation of sterol regulatory element-binding protein 1 (SREBP1) expression (P<0.05, P<0.01). ConclusionDanhe granules improve lipid metabolism disorders in mixed hyperlipidemia by reducing MDA levels, enhancing SOD and CAT activities, scavenging excessive ROS, inhibiting oxidative stress, and mitigating liver injury. The underlying mechanism may involve the upregulation of PPARA and LPL and the suppression of SREBP1 expression.
7.Construction and in vitro osteogenic activity study of magnesium-strontium co-doped hydroxyapatite mineralized collagen
WANG Meng ; SUN Yifei ; CAO Xiaoqing ; WEI Yiyuan ; CHEN Lei ; ZHANG Zhenglong ; MU Zhao ; ZHU Juanfang ; NIU Lina
Journal of Prevention and Treatment for Stomatological Diseases 2026;34(1):15-28
Objective:
To investigate the efficacy of magnesium-strontium co-doped hydroxyapatite mineralized collagen (MSHA/Col) in improving the bone repair microenvironment and enhancing bone regeneration capacity, providing a strategy to address the insufficient biomimetic composition and limited bioactivity of traditional hydroxyapatite mineralized collagen (HA/Col) scaffolds.
Methods:
A high-molecular-weight polyacrylic acid-stabilized amorphous calcium magnesium strontium phosphate precursor (HPAA/ACMSP) was prepared. Its morphology and elemental distribution were characterized by high-resolution transmission electron microscopy (TEM) and energy-dispersive spectroscopy. Recombinant collagen sponge blocks were immersed in the HPAA/ACMSP mineralization solution. Magnesium-strontium co-doped hydroxyapatite was induced to deposit within collagen fibers (experimental group: MSHA/Col; control group: HA/Col). The morphological characteristics of MSHA/Col were observed using scanning electron microscopy (SEM). Its crystal structure and chemical composition were analyzed by X-ray diffraction and Fourier transform infrared spectroscopy, respectively. The mineral phase content was evaluated by thermogravimetric analysis. The scaffold's porosity, ion release, and in vitro degradation performance were also determined. For cytological experiments, CCK-8 assay, live/dead cell staining, alkaline phosphatase staining, alizarin red S staining, RT-qPCR, and western blotting were used to evaluate the effects of the MSHA/Col scaffold on the proliferation, viability, early osteogenic differentiation activity, late mineralization capacity, and gene and protein expression levels of key osteogenic markers [runt-related transcription factor 2 (Runx2), collagen type Ⅰ (Col-Ⅰ), osteopontin (Opn), and osteocalcin (Ocn)] in mouse embryonic osteoblast precursor cells (MC3T3-E1).
Results:
HPAA/ACMSP appeared as amorphous spherical nanoparticles under TEM, with energy spectrum analysis showing uniform distribution of carbon, oxygen, calcium, phosphorus, magnesium, and strontium elements. SEM results of MSHA/Col indicated successful complete intrafibrillar mineralization. Elemental analysis showed the mass fractions of magnesium and strontium were 0.72% (matching the magnesium content in natural bone) and 2.89%, respectively. X-ray diffraction revealed characteristic peaks of hydroxyapatite crystals (25.86°, 31°-34°). Infrared spectroscopy results showed characteristic absorption peaks for both collagen and hydroxyapatite. Thermogravimetric analysis indicated a mineral phase content of 78.29% in the material. The scaffold porosity was 91.6% ± 1.1%, close to the level of natural bone tissue. Ion release curves demonstrated sustained release behavior for both magnesium and strontium ions. The in vitro degradation rate matched the ingrowth rate of new bone tissue. Cytological experiments showed that MSHA/Col significantly promoted MC3T3-E1 cell proliferation (130% increase in activity at 72 h, P < 0.001). MSHA/Col exhibited excellent efficacy in promoting osteogenic differentiation, significantly upregulating the expression of osteogenesis-related genes and proteins (Runx2, Col-Ⅰ, Opn, Ocn) (P < 0.01).
Conclusion
The MSHA/Col scaffold achieves dual biomimicry of natural bone in both composition and structure, and effectively promotes osteogenic differentiation at the genetic and protein levels, breaking through the functional limitations of pure hydroxyapatite mineralized collagen. This provides a new strategy for the development of functional bone repair materials
8.Research progress on the regulation of JNK signaling pathway by traditional Chinese medicine for intervention in central nervous system diseases
Hongwei WANG ; Mingliang QIAO ; Chenyi ZHAO ; Pei ZHU ; Zilong WEI ; Yi MENG
China Pharmacy 2026;37(2):257-262
The c-Jun N-terminal kinase (JNK) signaling pathway, a key member of the mitogen-activated protein kinase (MAPK) family, plays a central role in the pathogenesis and progression of central nervous system (CNS) diseases by regulating core biological processes such as apoptosis, inflammatory responses, synaptic plasticity, and autophagy. This article sorts out and analyzes relevant literature published domestically and internationally in recent years, summarizing the mechanisms of action of the JNK signaling pathway in common CNS diseases and the research progress in traditional Chinese medicine (TCM) interventions in CNS diseases through the regulation of the JNK signaling pathway. Studies have shown that active components of TCM, such as berberine, paeoniflorin, and astragaloside Ⅳ, as well as compound formulations like Heixiaoyao san, Ditan tang, and Buyang huanwu tang, can exert neuroprotective effects in various CNS disorders, including Alzheimer’s disease, Parkinson’s disease, cerebral ischemia-reperfusion injury, and epilepsy, by inhibiting the aberrant activation of the JNK signaling pathway, thereby alleviating neuroinflammation, oxidative stress, and neuronal apoptosis, while improving synaptic function and cognitive behavioral deficits, regulating autophagy, and maintaining blood-brain barrier integrity.
9.Study on The Anti-aging Effects of Longevity-enriched Metabolite Dimethylglycine
Jie HU ; Gong-Yu PU ; Jun-Lin LI ; Ju CAO ; Zhi-Xin LIN ; Wei-Wei AN ; Xue-Meng LI ; Jing AN
Progress in Biochemistry and Biophysics 2026;53(4):1048-1061
ObjectiveThe exacerbating trend of global population aging poses profound socioeconomic and public health challenges, making the comprehensive elucidation of biological aging mechanisms and the discovery of effective anti-aging interventions an urgent priority in the life sciences. Based on our previous serum metabolomics findings that dimethylglycine, an intermediate metabolite of amino acid metabolism naturally present in the human body, was significantly enriched in the serum of longevity families, this study aimed to systematically investigate the anti-aging effects of dimethylglycine both in living organisms and in controlled laboratory environments, and to preliminarily elucidate its underlying molecular mechanisms. While existing literature indicates that dimethylglycine possesses antioxidant and immunomodulatory properties, its direct anti-aging efficacy and the specific molecular pathways through which it operates remain largely unexplored. MethodsTo comprehensively evaluate the anti-aging properties of dimethylglycine, we utilized replicative senescent human embryonic lung fibroblasts, specifically the WI-38 cell line, as an experimental model in a controlled laboratory environment. Cell viability and safety were thoroughly assessed using Cell Counting Kit-8 and lactate dehydrogenase release assays across various concentrations of dimethylglycine. The impact of dimethylglycine on cellular senescence phenotypes, oxidative stress, and proliferative capacity was evaluated via senescence-associated beta-galactosidase staining, reactive oxygen species fluorescence detection, and 5-ethynyl-2'-deoxyuridine incorporation assays. Furthermore, the molecular alterations of senescence-associated secretory phenotype factors and core senescence signaling pathways were quantified using quantitative reverse transcription polymerase chain reaction for the messenger RNA levels of interleukin-6, interleukin-8, p21, and matrix metalloproteinase-1, and enzyme-linked immunosorbent assay for the measurement of p16 and p21 protein expression levels. For the living organism model, the wild-type nematode Caenorhabditis elegans was used to evaluate systemic physiological effects. We conducted a comprehensive lifespan analysis at 20°C, heat stress resistance survival assays at 35℃, senescence-associated beta-galactosidase staining, lipofuscin accumulation tracking, intracellular reactive oxygen species measurement, and Oil Red O staining to ascertain systemic lipid accumulation. Additionally, network pharmacology bioinformatics tools, including PharmMapper and STRING databases, and Kyoto Encyclopedia of Genes and Genomes pathway enrichment analysis were utilized to predict target pathways, alongside highly detailed molecular docking simulations utilizing SwissDock and Protein-Ligand Interaction Profiler to examine interactions with the cytochrome P450 family 2 subfamily C member 9 protein. ResultsThe experimental outcomes robustly demonstrate the potent anti-aging capabilities of dimethylglycine. At the cellular level, toxicity analyses firmly confirmed that dimethylglycine is highly safe; continuous treatment with 50 mol/L and 70 mol/L of dimethylglycine for 5 d did not induce any cellular membrane damage or cytotoxicity, but rather actively promoted cellular proliferation. Utilizing the optimal standardized concentration of 50 mol/L, dimethylglycine treatment significantly ameliorated senescent phenotypic markers in human embryonic lung fibroblasts, which was evidenced by a drastic and highly significant reduction in the senescence-associated beta-galactosidase positive cell percentage (P<0.000 1) and intracellular reactive oxygen species levels (P<0.000 1), alongside a marked increase in the 5-ethynyl-2'-deoxyuridine-positive proliferation rate (P=0.003 5). On a molecular expression scale, dimethylglycine significantly downregulated the messenger RNA expression of multiple core senescence-associated secretory phenotype inflammatory factors, including interleukin-6, interleukin-8, p21, and matrix metalloproteinase-1. Concurrently, it effectively suppressed the protein expression of critical cell cycle arrest markers, diminishing p16 protein levels by 57.3% (P=0.000 4) and p21 protein levels by 27.2% (P=0.000 7). In the nematode Caenorhabditis elegans animal model, dimethylglycine significantly extended the mean lifespan from 20.402 d to an impressive 23.066 d (P<0.000 1) and notably enhanced overall survival rates under severe heat stress environmental conditions (P=0.017). Furthermore, systemic dimethylglycine intervention significantly mitigated age-related physiological decline by decreasing bodily lipofuscin accumulation (P<0.000 1), significantly reducing senescence-associated beta-galactosidase activity, lowering systemic reactive oxygen species fluorescence (P=0.008), and effectively alleviating overall fat accumulation (P<0.000 1). Mechanistically, extensive network pharmacology and Kyoto Encyclopedia of Genes and Genomes analyses strongly revealed that the potential targets of dimethylglycine are significantly enriched in fundamental drug metabolism and oxidative stress response pathways. Precision molecular docking simulations conclusively demonstrated that dimethylglycine forms highly stable structural interactions with the cytochrome P450 family 2 subfamily C member 9 protein, specifically highlighting the definitive formation of 5 stable hydrogen bonds involving serine 365, leucine 366, and serine 429 residues, as well as two critical salt bridge formations with arginine 97 and histidine 368 residues. It is additionally predicted to interact favorably with glutathione S-transferase family proteins. ConclusionDimethylglycine exhibits a profoundly significant and multifaceted anti-aging activity at both the cellular and entire living animal levels. By powerfully alleviating oxidative stress, heavily suppressing the core p16 and p21-dependent cellular senescence signaling pathways, and substantially mitigating the detrimental senescence-associated secretory phenotype, dimethylglycine effectively delays fundamental cellular senescence processes and drastically extends whole-organism lifespan. The biological mechanisms driving these robust protective effects are highly likely closely associated with its direct stable interactions with crucial metabolic and detoxifying enzyme systems, such as cytochrome P450 family 2 subfamily C member 9 and glutathione S-transferase family proteins, thereby systemically improving metabolic dysregulation and restoring critical redox homeostasis. This comprehensive study provides highly solid experimental evidence supporting dimethylglycine as a highly potent and safe potential anti-aging intervention agent, while simultaneously offering a clear molecular mechanistic explanation for the previously documented high abundance of dimethylglycine observed within exceptionally long-lived human populations.
10.Establishment and Preliminary Analysis of GP73 Interactome Using Proximity-dependent Labeling Technology
Mu-Yi LIU ; Chang ZHANG ; Meng-Xin YANG ; Xin-Long YAN ; Lu-Ming WAN ; Cong-Wen WEI
Progress in Biochemistry and Biophysics 2026;53(3):711-723
ObjectiveProtein-protein interactions (PPIs) are fundamental to the execution of biological functions within living cells. However, traditional biochemical methods, such as co-immunoprecipitation (Co-IP), often fail to capture transient, weak, or membrane-associated interactions due to the stringent detergent requirements for cell lysis. Proximity labeling (PL) has emerged in recent years as a transformative technology for mapping the proteomes of specific subcellular compartments and identifying dynamic interactomes in situ. Golgi protein 73 (GP73, also known as GOLPH2), a resident type II Golgi transmembrane protein, is a well-recognized clinical biomarker for liver diseases, including hepatocellular carcinoma (HCC). Despite its clinical significance, the comprehensive physiological and pathological functions of GP73 remain partially understood. This study aims to establish an APEX2-mediated proximity labeling system specifically targeting GP73 to map its interactome in a living cellular environment, thereby providing new insights into its molecular roles and regulatory mechanisms. MethodsTo achieve spatial specificity, we first constructed a stable cell line expressing a fusion protein consisting of GP73 and the engineered soybean peroxidase APEX2. The localization of the GP73-APEX2 fusion protein was validated to ensure it correctly targeted the Golgi apparatus. The proximity labeling reaction was initiated by incubating the cells with biotin-phenol (BP) for 30 min, followed by a brief (1 min) treatment with1 mmol/L hydrogen peroxide (H2O2). This catalytic reaction converts BP into highly reactive, short-lived biotin-phenoxyl radicals that covalently attach to endogenous proteins within a small labeling radius of the GP73-APEX2 enzyme. Subsequently, the cells were quenched, and biotinylated proteins were enriched using high-affinity streptavidin-coated magnetic beads. The captured “neighbor” proteins were subjected to on-bead digestion and analyzed via liquid chromatography-tandem mass spectrometry (LC-MS/MS) for high-throughput identification. Rigorous bioinformatics analysis, including Gene Ontology (GO) enrichment, Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis, and protein-protein interaction network mapping, was performed to interpret the biological significance of the identified candidates. ResultsOur results demonstrate the successful establishment of a robust and sensitive APEX2-based proximity labeling system for GP73. We identified a total of 95 high-confidence interacting proteins that were significantly enriched in the GP73 proximity proteome compared to control groups. Bioinformatics analysis revealed that these interactors were predominantly associated with biological processes such as vesicular transport, protein localization, and, most notably, molecular functions related to “ribosome binding” and “translation regulation”. This suggested an unexpected role for the Golgi-resident GP73 in the cellular translation machinery. To validate these findings, we performed targeted biochemical assays which confirmed a direct interaction between GP73 and the subunits of the eukaryotic translation initiation factor 3 (eIF3) complex, specifically EIF3G and EIF3I. Furthermore, functional validation using the surface sensing of translation (SUnSET) assay—a non-radioactive method to monitor protein synthesis—revealed that the overexpression of GP73 significantly promoted global protein translation levels in the cell, whereas its depletion or inhibition resulted in reduced translation efficiency. ConclusionThis study successfully utilized APEX2-mediated proximity labeling to provide the first systematic map of GP73 interactome in living cells. Our findings uncover a novel, unconventional function of GP73 as a regulator of cellular protein translation, likely mediated through its interaction with the eIF3 complex. This discovery significantly broadens our understanding of the biological roles of GP73 beyond its traditional function in the Golgi apparatus and suggests that it may act as a bridge between Golgi-related trafficking and the protein synthesis machinery. Furthermore, the technical framework established in this study provides a valuable template for investigating other complex organelle-associated protein networks and resolving transient macromolecular interactions in various physiological and pathological contexts.


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