1.SIRT5 Potentiates Hepatocarcinogenesis by Modulating Protein Acylation in Mice
Yu ZHANG ; Feng-Rui REN ; Jia-Yun LI ; Xiang-Yu CHEN ; Zi-Yi WANG ; Qi SUN ; Jun-Cheng ZHAO ; Ye ZHANG ; Zhen HUANG ; Hao HU ; Tao-Tao WEI ; Min XIAO
Progress in Biochemistry and Biophysics 2026;53(6):1712-1722
ObjectiveHepatocellular carcinoma (HCC) represents 90% of all primary liver cancers. The main risk factors associated with HCC include viral hepatitis (B and/or C), alcohol abuse, and metabolic dysfunction-associated steatotic liver disease (MASLD), which progressively advance to liver fibrosis, cirrhosis, and ultimately evolve into HCC. Surgical resection represents the most effective treatment for HCC, while recent advances in immunotherapy, including immune checkpoint inhibitors and adoptive cell therapies, have provided improved treatment prospects for patients with unresectable HCC. However, the complex metabolic heterogeneity of HCC limits the therapeutic efficacy. Metabolic intermediates acyl-CoA not only provide energy and substrates for numerous biochemical reactions but also serve as donors for protein lysine acylation, a major class of post-translational modification (PTM). Therefore, a deeper understanding of the molecular mechanisms underlying protein lysine acylation and hepatocarcinogenesis is urgently needed. MethodsThe levels of protein lysine acylation and silence information regulator 5 (SIRT5) expression levels in clinical HCC samples were analyzed by Western blot. Quantitative malonylome and succinylome of HCC samples were analyzed by antibody-based affinity enrichment coupled with tandem mass spectrometry. The proliferation of HCC cells was analyzed with Cell Counting Kit-8 (CCK-8) assays, the apoptosis was quantified by Annexin V-FITC/propidium iodide (PI) staining coupled with flow cytometry, and the ability of cells to migrate was assayed by Transwell assays. The enzymatic activity of glutathione S-transferase Mu 1 (GSTM1) was quantified. Transgenic mice with hepatic overexpression of SIRT5 were constructed using CRISPR-Cas9, and primary hepatocarcinogenesis was induced by administration of diethylnitrosamine. ResultsWestern blot analysis indicated that the expression level of SIRT5 was elevated in clinical samples from HCC patients, and the levels of lysine malonylation, glutarylation, and succinylation were significantly reduced in HCC tissues. Knockout of SIRT5 in MHCC-97H and MHCC-97L hepatoma cells suppressed cell proliferation, and increased the percentage of apoptotic cells significantly. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analyses of the differentially malonylome and succinylome of HCC samples revealed significant enrichment in two major classes of biological processes: core energy metabolism (e.g., glycolysis/gluconeogenesis, tricarboxylic acid metabolic process, fatty acid beta oxidation) and detoxification and oxidative stress response (e.g., response to toxic substance, chemical carcinogenesis, reactive oxygen species (ROS)). SIRT5 removes malonylation from lysine residues in GSTM1 and restores its detoxification activity, which is crucial for the survival of hepatocytes under stressed conditions. More importantly, in vivo experiment indicated that hepatic-specific overexpression of SIRT5 in mice accelerated diethylnitrosamine-induced liver fibrosis and hepatocarcinogenesis, indicating the critical role of SIRT5 in HCC progression. ConclusionThis study highlights the previously unrecognized SIRT5-GSTM1 axis as a key regulator in hepatocarcinogenesis, and suggests a potential target for the treatment of patients with HCC.
2.The Dual Role and Clinical Potential of Core Fucosylation in Liver Diseases
Zi-Han LEI ; Hui-Min XU ; De-Zhi ZHAO ; Yong-Hong GUO ; Hao-Qi DU
Progress in Biochemistry and Biophysics 2026;53(8):2161-2178
Core fucosylation, catalyzed exclusively by fucosyltransferase 8 (FUT8), is an evolutionarily conserved post-translational modification that has emerged as a central regulatory hub linking liver homeostasis, chronic disease progression, and malignant transformation. Liver diseases, particularly hepatocellular carcinoma, remain a leading global health burden characterized by late diagnosis, limited therapeutic options, and poor overall survival. While aberrant glycosylation is now recognized as a hallmark of cancer and inflammatory disorders, existing research on FUT8-mediated core fucosylation in liver diseases remains fragmented: the dynamic functional switch of FUT8 from a homeostatic regulator to a pathological driver across the full disease continuum has not been systematically delineated, and the integrated mechanisms by which core fucosylation modulates oncogenic signaling, metabolic reprogramming, and immune evasion remain poorly understood. This review synthesizes recent advances to establish a unified framework for understanding the dual role of core fucosylation in liver physiology and pathology, and evaluates its translational potential for precision medicine. At the molecular level, FUT8’s unique catalytic specificity makes core fucosylation an irreplaceable modification, as evidenced by the perinatal lethality and severe organ dysfunction in Fut8 knockout mice. In hepatocellular carcinoma, genomic amplification of guanosine 5'-diphosphate-fucose biosynthetic enzymes provides metabolic support for aberrant core fucosylation. FUT8 expression is tightly regulated by a multi-layered network: transcriptional activation via Wnt/β‑catenin and wild-type p53, epigenetic upregulation by lncRNAs, post-transcriptional repression by miR-122-5p and miR-34a, and virus-specific induction by hepatitis B virus/hepatitis C virus. Physiologically, core fucosylation maintains liver homeostasis through four core mechanisms: it acts as a molecular switch for epidermal growth factor receptor/hepatocyte growth factor receptor signaling to enable liver regeneration; directs polarized secretion of hepatocyte-derived glycoproteins into bile ducts; modulates cholesterol metabolism via the hepatocyte nuclear factor 1α-proprotein convertase subtilisin/kexin type 9-low density lipoprotein receptor axis; and regulates aging through insulin‑like growth factor 1 receptor signaling. Pathologically, core fucosylation exhibits context-dependent dual functions: in liver fibrosis, FUT8 upregulation in hepatic stellate cells forms a negative feedback loop that limits excessive fibrogenesis; in hepatocellular carcinoma, however, aberrant FUT8 overexpression drives cell-autonomous malignancy by constitutively activating epidermal growth factor/hepatocyte growth factor receptor, transforming growth factor‑β/Smad, and Wnt/β‑catenin pathways, while simultaneously establishing a multi-layered immune evasion network by stabilizing programmed cell death ligand 1 and cluster of differentiation 47, and impairing natural killer cell homeostasis via interleukin‑2 receptor β glycosylation. Clinically, stage-specific core fucosylation biomarkers enable non-invasive monitoring of liver disease progression: low molecular mass kringle-Fc fusion protein outperforms conventional markers for early fibrosis detection, while alpha-fetoprotein-L3 and novel glycopeptides (α‑2‑macroglobulin N‑linked glycosylation site 1424, lumican core fucosylated peptide) significantly improve early hepatocellular carcinoma diagnosis, especially in alpha-fetoprotein-negative patients. Next-generation detection technologies (chemoenzymatic labeling, site-specific mass spectrometry) overcome the specificity limitations of traditional lectin assays. Therapeutically, four promising strategies are emerging: small-molecule FUT8 inhibitors, afucosylated antibodies with enhanced antibody‑dependent cellular cytotoxicity, Fuc-modified targeted drug delivery systems, and core fucose-specific lectins for NASH treatment. The core challenge for clinical translation lies in FUT8’s inherent “double-edged sword” effect, as systemic inhibition disrupts its essential physiological functions beyond pathological roles. Long-term systemic FUT8 blockade not only impairs post-injury liver regeneration by abrogating epidermal growth factor/hepatocyte growth factor receptor signaling but also disrupts cholesterol homeostasis via the hepatocyte nuclear factor 1α-proprotein convertase subtilisin/kexin type 9-low density lipoprotein receptor axis, leading to dyslipidemia and altered bile secretion. Critically, it compromises immune surveillance by destabilizing interleukin‑2 receptor β on natural killer cells, reducing their cytotoxic activity against malignant and virally infected cells, and impairs IgG Fc-mediated effector functions, increasing susceptibility to infections. This fundamental trade-off between therapeutic efficacy and systemic toxicity necessitates a paradigm shift from non-specific global inhibition to precision modulation of pathological core fucosylation. By addressing these critical challenges, FUT8-mediated core fucosylation has the potential to transform liver disease management from late-stage intervention to early detection and precision therapy, ultimately improving patient outcomes and reducing the global burden of liver diseases.
3.Metabolic Dysregulation-driven Protein Acylation in Osteoarthritis
Zi-Hao ZHANG ; Li DUAN ; Kan OUYANG ; Tayyab SHAFIQ
Progress in Biochemistry and Biophysics 2026;53(10):2703-2713
Osteoarthritis (OA) is a common chronic degenerative joint disease and a major cause of pain and disability, particularly in middle-aged and older adults. OA is now recognized as a whole-joint disorder involving articular cartilage, synovium, subchondral bone, the meniscus, the infrapatellar fat pad, and the local inflammatory microenvironment. In addition to mechanical factors, metabolic abnormalities such as obesity, dyslipidemia, insulin resistance, and hyperglycemia are increasingly recognized as contributors to OA onset and progression. Obesity can increase mechanical joint loading, whereas metabolic abnormalities alter cellular metabolism and inflammatory responses within joint tissues. However, the molecular mechanisms by which metabolic stress leads to persistent cellular dysfunction and tissue damage remain incompletely understood. Protein acylation links cellular metabolism to chromatin regulation and protein function. Its dynamic balance is influenced by acyl-donor availability, cellular redox status, mitochondrial activity, glycolytic flux, and the activities of acyltransferases and deacylases. In OA, mitochondrial dysfunction, enhanced glycolysis, lactate accumulation, altered acyl-CoA metabolism, and dysregulated NAD+-dependent deacylation may reshape histone and non-histone protein acylation. These changes have been implicated in inflammatory gene expression, extracellular matrix metabolism, mitochondrial quality control, chondrocyte senescence, ferroptosis susceptibility, and synovial immune dysfunction. Recent studies increasingly focus on defined acylation sites, target proteins, regulatory enzymes, and cell-type-specific effects. Acetylation and deacetylation are involved in OA-related processes. sirtuin 1 (SIRT1)-mediated regulation of nuclear factor kappa-B (NF-κB) p65 acetylation is associated with inflammatory and catabolic responses, whereas histone deacetylase 3 (HDAC3)-dependent control of Parkin acetylation links matrix stiffening to excessive mitophagy and chondrocyte senescence. SIRT3-related pathways connect nicotinamide adenine dinucleotide (NAD+)-dependent deacetylation with mitochondrial DNA integrity, mitochondrial renewal, and metabolic remodeling, while SIRT6 has been implicated in inflammation and cellular senescence. Lactylation has emerged as another important direction in OA research. Histone H3 lysine 18 (H3K18) lactylation is associated with glycolysis-related transcription through the lactate dehydrogenase A (LDHA)-H3K18la-triosephosphate isomerase 1 (TPI1) axis. UGDH K6 lactylation impairs glycosaminoglycan synthesis and promotes matrix damage, whereas H4K12 lactylation has been linked to chondrocyte senescence and autophagy inhibition. In the synovial microenvironment, cluster of differentiation 11b (CD11b) lactylation in macrophages impairs efferocytosis and contributes to sustained inflammation under hyperglycemic conditions. In contrast, H3K56 lactylation has been associated with increased type II collagen synthesis in a post-traumatic OA model, indicating that lactylation effects depend on the modified site, target, cell state, and disease context. SIRT5-related malonylation and succinylation provide additional links between acylation and metabolic dysfunction in OA. Increased protein malonylation and reduced SIRT5 activity are associated with disturbed glycolysis, mitochondrial respiration, and carbon metabolism in chondrocytes. SIRT5-mediated acyl-CoA synthetase long-chain family member 4 (ACSL4) desuccinylation has been linked to reduced lipid peroxidation and ferroptosis susceptibility. By contrast, OA-specific evidence for crotonylation remains limited and centers on crotonylation-related metabolic genes such as glutaryl-CoA dehydrogenase (GCDH) rather than defined functional acylation sites. This review summarizes current evidence linking metabolic dysregulation to acylation regulation in OA. Collectively, available studies indicate that shared metabolic disturbances reshape distinct acylation programs across joint cell types, producing modification- and site-specific effects on cellular function and tissue homeostasis. However, evidence strength varies among acylation types, particularly regarding defined functional sites and in vivo causality. Further site-specific and in vivo studies are needed to clarify which acylation changes actively contribute to OA progression and to evaluate their mechanistic and therapeutic relevance.
4.Effects of honey-processed Astragalus on energy metabolism and polarization of RAW264.7 cells
Hong-chang LI ; Ke PEI ; Wang-yang XIE ; Xiang-long MENG ; Zi-han YU ; Wen-ling LI ; Hao CAI
Acta Pharmaceutica Sinica 2025;60(2):459-470
In this study, RAW264.7 cells were employed to investigate the effects of honey-processed
5.Clinical effects of Qijing Buzhong Yishen Decoction on patients with diabetic nephropathy due to Spleen-Kidney Qi Deficiency and Blood Stasis Obstructing Collaterals
Hao-yu YUAN ; Zi-cheng YE ; Wen-kai XU ; Sai-mei LI
Chinese Traditional Patent Medicine 2025;47(10):3264-3269
AIM To explore the clinical effects of Qijing Buzhong Yishen Decoction on patients with diabetic nephropathy due to Spleen-Kidney Qi Deficiency and Blood Stasis Obstructing Collaterals.METHODS One hundred and two patients were randomly assigned into control group(51 cases)for 3-month intervention of conventional treatment,and observation group(51 cases)for 3-month intervention of both Qijing Buzhong Yishen Decoction and conventional treatment.The changes in clinical effects,blood glucose indices(fasting blood glucose,2 h postprandial blood glucose,HbA1c,TIR),blood lipid indices(TC,TG,LDL-C),renal function indices(UACR,eGFR,24 h urinary albumin excretion rate,sustained urinary albumin excretion rate),inflammatory factors(IL-6,hs-CRP,TNF-α),TCM syndrome scores and incidence of adverse reactions were detected.RESULTS The observation group demonstrated higher total effective rate than the control group(P<0.05).After the treatment,the two groups displayed decreased fasting blood glucose,2 h postprandial blood glucose,HbA1c,UACR,24 h urinary albumin excretion rate,sustained urinary albumin excretion rate,inflammatory factors,TCM syndrome scores(P<0.05),and increased TIR,eGFR(P<0.05),especially for the observation group(P<0.05).No serious adverse reactions were observable in the two groups.CONCLUSION For the patients with diabetic nephropathy due to Spleen-Kidney Qi Deficiency and Blood Stasis Obstructing Collaterals,Qijing Buzhong Yishen Decoction can safely and effectively regulate the blood sugar levels,and improve renal functions.
6.The application value of musculoskeletal ultrasound in grading acute gastrocnemius muscle injuries
Zi-Li CHEN ; Mi YANG ; Hao LIANG ; Xiao-Xiong MEI ; Li YANG ; Hui-Juan XIANG ; Rui DU
Medical Journal of Chinese People's Liberation Army 2025;50(5):553-557
Objective To explore the application value of musculoskeletal ultrasound(MSUS)in grading acute gastrocnemius muscle injuries.Methods A retrospective analysis was conducted on ultrasound images of 291 patients who presented with sudden calf pain and suspected acute gastrocnemius muscle injury in the General Hospital of Central Theater Command from March 2019 to July 2024.The images were independently reviewed and assessed by three ultrasound doctors with different qualifications to determine the presence and grade of gastrocnemius muscle injury.The consistency of grading results among three doctors was compared.The diagnostic results of three doctors were summarized.Then,the diagnostic results of 29 patients who underwent routine MRI scans were compared with those of MSUS,and the agreement between the two imaging modalities was assessed using the Kappa test.Results Among the 291 patients,171 cases(58.8%)were diagnosed with gastrocnemius muscle injury,including 55 cases(32.2%)with grade Ⅰ,109 cases(63.7%)with grade Ⅱ,and 7 cases(4.1%)with grade Ⅲ.There were 159 cases(93.0%)of unilateral medial head injury,10 cases(5.8%)of unilateral lateral head injury,and 2 cases(1.2%)of bilateral medial and lateral head injury.Compared with patients without gastrocnemius muscle injury,patients with gastrocnemius muscle injury were older(P<0.05),with no significant difference in gender and laterality(P>0.05).No significant differences in baseline characteristics were found among patients with different grades of injury(P>0.05).The three doctors diagnosed 173(59.5%),171(58.8%),and 171(58.8%)cases of injury,respectively,with an inter-class correlation coefficient(ICC)of 0.947(P<0.001).Among 29 patients who underwent MRI,the diagnostic agreement between MRI and ultrasound for grade Ⅰ,Ⅱ and Ⅲ injury was 8(27.6%),18(62.1%)and 3(10.3%)for MRI;and 9(31.0%),17(58.6%)and 3(10.3%)for MSUS,respectively,with a Kappa value of 0.808(P<0.001).Conclusions MSUS is effective for assessing the grade of acute gastrocnemius muscle injury,and shows high diagnostic consistency among doctors with different qualifications.It is recommended as the preferred method for diagnosing gastrocnemius muscle injury.
7.Research progress of an immune checkpoint molecule VISTA in hematological tumors
Zi-Jun TANG ; Han-Xue ZHENG ; Hao XIONG ; Lian-Sheng ZHANG ; Li-Juan LI
Medical Journal of Chinese People's Liberation Army 2025;50(6):672-678
Research on immune checkpoints such as programmed death protein-1(PD-1)and cytotoxic T lymphocyte antigen-4(CTLA-4)has provided new directions for tumor treatment.V-domain immunoglobulin suppressor of T-cell activation(VISTA)is an emerging immune checkpoint within the B7 family.Functioning as both a ligand and a receptor,VISTA is an inhibitory immune checkpoint molecule expressed in tumor cells,myeloid cells and T lymphocytes.It plays a crucial role in regulating autoimmunity,inflammatory response and tumor immunity.The non-redundant interactions between VISTA and other immune checkpoints,such as PD-1,may offer new therapeutic strategies and serve as a new target for overcoming immunotherapy resistance.This review summarizes the recent research progress on VISTA in hematological tumors,aiming to provide new insights into its application in the treatment of these malignancies.
8.Association between acupuncture and live birth rates after fresh embryo transfer: A cohort study based on different propensity score methods.
Xiao-Yan ZHENG ; Zi-Yi JIANG ; Yi-Ting LI ; Chao-Liang LI ; Hao ZHU ; Zheng YU ; Si-Yi YU ; Li-Li YANG ; Song-Yuan TANG ; Xing-Yu LÜ ; Fan-Rong LIANG ; Jie YANG
Journal of Integrative Medicine 2025;23(5):528-536
OBJECTIVE:
To explore the association between acupuncture during controlled ovarian hyperstimulation (COH) and the live birth rate (LBR) using different propensity score methods.
METHODS:
In this retrospective cohort study, eligible women who underwent a COH were divided into acupuncture and non-acupuncture groups. The primary outcome was LBR, as determined by propensity score matching (PSM). LBR was defined as the delivery of one or more living infants that reached a gestational age over 28 weeks after embryo transfer. The propensity score model encompassed 16 confounding variables. To validate the results, sensitivity analyses were conducted using three additional propensity score methods: propensity score adjustment, inverse probability weighting (IPW), and IPW with a "doubly robust" estimator.
RESULTS:
The primary cohort encompassed 9751 patients (1830 [18.76%] in the acupuncture group and 7921 [81.23%] in the non-acupuncture group). Following 1:1 PSM, a higher LBR was found in the acupuncture cohort (41.4% [755/1824] vs 36.4% [664/1824], with an odds ratio of 1.23 [95% confidence interval, 1.08-1.41]). Three additional propensity score methods produced essentially similar results. The risk of serious adverse events did not significantly differ between the two groups.
CONCLUSION
This retrospective study revealed an association between acupuncture and an increased LBR among patients undergoing COH, and that acupuncture is a safe and valuable treatment option. Please cite this article as: Zheng XY, Jiang ZY, Li YT, Li CL, Zhu H, Yu Z, Yu SY, Yang LL, Tang SY, Lü XY, Liang FR, Yang J. Association between acupuncture and live birth rates after fresh embryo transfer: A cohort study based on different propensity score methods. J Integr Med. 2025; 23(5):528-536.
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Birth Rate
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Cohort Studies
9.Neuroplasticity Mechanisms of Exercise-induced Brain Protection
Li-Juan HOU ; Lan-Qun MAO ; Wei CHEN ; Ke LI ; Xu-Dong ZHAO ; Yin-Hao WANG ; Zi-Zheng YANG ; Tian-He WEI
Progress in Biochemistry and Biophysics 2025;52(6):1435-1452
Neuroscience is a significant frontier discipline within the natural sciences and has become an important interdisciplinary frontier scientific field. Brain is one of the most complex organs in the human body, and its structural and functional analysis is considered the “ultimate frontier” of human self-awareness and exploration of nature. Driven by the strategic layout of “China Brain Project”, Chinese scientists have conducted systematic research focusing on “understanding the brain, simulating the brain, and protecting the brain”. They have made breakthrough progress in areas such as the principles of brain cognition, mechanisms and interventions for brain diseases, brain-like computation, and applications of brain-machine intelligence technology, aiming to enhance brain health through biomedical technology and improve the quality of human life. Due to limited understanding and comprehension of neuroscience, there are still many important unresolved issues in the field of neuroscience, resulting in a lack of effective measures to prevent and protect brain health. Therefore, in addition to actively developing new generation drugs, exploring non pharmacological treatment strategies with better health benefits and higher safety is particularly important. Epidemiological data shows that, exercise is not only an indispensable part of daily life but also an important non-pharmacological approach for protecting brain health and preventing neurodegenerative diseases, forming an emerging research field known as motor neuroscience. Basic research in motor neuroscience primarily focuses on analyzing the dynamic coding mechanisms of neural circuits involved in motor control, breakthroughs in motor neuroscience research depend on the construction of dynamic monitoring systems across temporal and spatial scales. Therefore, high spatiotemporal resolution detection of movement processes and movement-induced changes in brain structure and neural activity signals is an important technical foundation for conducting motor neuroscience research and has developed a set of tools based on traditional neuroscience methods combined with novel motor behavior decoding technologies, providing an innovative technical platform for motor neuroscience research. The protective effect of exercise in neurodegenerative diseases provides broad application prospects for its clinical translation. Applied research in motor neuroscience centers on deciphering the regulatory networks of neuroprotective molecules mediated by exercise. From the perspectives of exercise promoting neurogenesis and regeneration, enhancing synaptic plasticity, modulating neuronal functional activity, and remodeling the molecular homeostasis of the neuronal microenvironment, it aims to improve cognitive function and reduce the incidence of Parkinson’s disease and Alzheimer’s disease. This has also advanced research into the molecular regulatory networks mediating exercise-induced neuroprotection and facilitated the clinical application and promotion of exercise rehabilitation strategies. Multidimensional analysis of exercise-regulated neural plasticity is the theoretical basis for elucidating the brain-protective mechanisms mediated by exercise and developing intervention strategies for neurological diseases. Thus,real-time analysis of different neural signals during active exercise is needed to study the health effects of exercise throughout the entire life cycle and enhance lifelong sports awareness. Therefore, this article will systematically summarize the innovative technological developments in motor neuroscience research, review the mechanisms of neural plasticity that exercise utilizes to protect the brain, and explore the role of exercise in the prevention and treatment of major neurodegenerative diseases. This aims to provide new ideas for future theoretical innovations and clinical applications in the field of exercise-induced brain protection.
10.In situ Analytical Techniques for Membrane Protein Interactions
Zi-Yuan KANG ; Tong YU ; Chao LI ; Xue-Hua ZHANG ; Jun-Hui GUO ; Qi-Chang LI ; Jing-Xing GUO ; Hao XIE
Progress in Biochemistry and Biophysics 2025;52(5):1206-1218
Membrane proteins are integral components of cellular membranes, accounting for approximately 30% of the mammalian proteome and serving as targets for 60% of FDA-approved drugs. They are critical to both physiological functions and disease mechanisms. Their functional protein-protein interactions form the basis for many physiological processes, such as signal transduction, material transport, and cell communication. Membrane protein interactions are characterized by membrane environment dependence, spatial asymmetry, weak interaction strength, high dynamics, and a variety of interaction sites. Therefore, in situ analysis is essential for revealing the structural basis and kinetics of these proteins. This paper introduces currently available in situ analytical techniques for studying membrane protein interactions and evaluates the characteristics of each. These techniques are divided into two categories: label-based techniques (e.g., co-immunoprecipitation, proximity ligation assay, bimolecular fluorescence complementation, resonance energy transfer, and proximity labeling) and label-free techniques (e.g., cryo-electron tomography, in situ cross-linking mass spectrometry, Raman spectroscopy, electron paramagnetic resonance, nuclear magnetic resonance, and structure prediction tools). Each technique is critically assessed in terms of its historical development, strengths, and limitations. Based on the authors’ relevant research, the paper further discusses the key issues and trends in the application of these techniques, providing valuable references for the field of membrane protein research. Label-based techniques rely on molecular tags or antibodies to detect proximity or interactions, offering high specificity and adaptability for dynamic studies. For instance, proximity ligation assay combines the specificity of antibodies with the sensitivity of PCR amplification, while proximity labeling enables spatial mapping of interactomes. Conversely, label-free techniques, such as cryo-electron tomography, provide near-native structural insights, and Raman spectroscopy directly probes molecular interactions without perturbing the membrane environment. Despite advancements, these methods face several universal challenges: (1) indirect detection, relying on proximity or tagged proxies rather than direct interaction measurement; (2) limited capacity for continuous dynamic monitoring in live cells; and (3) potential artificial influences introduced by labeling or sample preparation, which may alter native conformations. Emerging trends emphasize the multimodal integration of complementary techniques to overcome individual limitations. For example, combining in situ cross-linking mass spectrometry with proximity labeling enhances both spatial resolution and interaction coverage, enabling high-throughput subcellular interactome mapping. Similarly, coupling fluorescence resonance energy transfer with nuclear magnetic resonance and artificial intelligence (AI) simulations integrates dynamic structural data, atomic-level details, and predictive modeling for holistic insights. Advances in AI, exemplified by AlphaFold’s ability to predict interaction interfaces, further augment experimental data, accelerating structure-function analyses. Future developments in cryo-electron microscopy, super-resolution imaging, and machine learning are poised to refine spatiotemporal resolution and scalability. In conclusion, in situ analysis of membrane protein interactions remains indispensable for deciphering their roles in health and disease. While current technologies have significantly advanced our understanding, persistent gaps highlight the need for innovative, integrative approaches. By synergizing experimental and computational tools, researchers can achieve multiscale, real-time, and perturbation-free analyses, ultimately unraveling the dynamic complexity of membrane protein networks and driving therapeutic discovery.

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