Zhang J, Liu C, Tang Y, Gao K, Xu W, Zhang J, Zhao L, Wang G.
Erbin destabilization by O-GlcNAcylation promotes 5-FU resistance via homologous recombination activation in colorectal cancer.
Biochemical pharmacology2026
243(Pt 1)
41072816
Abstract: The emergence of 5-fluorouracil (5FU) resistance critically compromises chemotherapy efficacy in colorectal cancer (CRC). While O-GlcNAcylation-a dynamic post-translational modification linked to tumor progression-has been widely investigated, its functional role in 5FU chemoresistance remains poorly defined. Through mass spectrometry and tissue microarray analysis, we identified aberrantly elevated levels of O-GlcNAcylation and its catalytic enzyme O-GlcNAc transferase (OGT) in CRC tissues. Genetic silencing of OGT significantly reduced global O-GlcNAcylation, suppressing CRC cell proliferation, migration, and invasion while enhancing 5FU sensitivity both in vitro and in vivo. Notably, 5FU-resistant CRC models (HCT8/HCT116 5FUR) exhibited upregulated OGT and O-GlcNAcylation versus parental cells. Strikingly, OGT knockdown in resistant cells reversed chemoresistance, inhibited proliferation, and induced apoptosis. O-GlcNAcylated proteomic profiling identified Erbin, a tumor suppressor, as a hyper-modified protein with diminished expression in resistant cells, validated by co-immunoprecipitation. Remarkably, Erbin overexpression restored 5FU sensitivity in resistant cells, whereas OGT depletion stabilized Erbin by blocking ubiquitination. Site-directed mutagenesis pinpointed Thr1070 as Erbin's critical O-GlcNAcylation site; its mutation reduced ubiquitination, linking O-GlcNAcylation to Erbin degradation. Mechanistically, RNA sequencing (RNA-seq) revealed that Erbin suppresses homologous recombination (HR), causing unresolved DNA damage accumulation and heightened 5FU sensitivity, confirmed in vitro and in vivo experiments. Critically, elevated OGT in 5FU-resistant cells drives hyper-O-GlcNAcylation of Erbin at Thr1070, which facilitates its ubiquitin-dependent degradation, alleviating HR suppression to sustain chemoresistance. This defines the OGT-Erbin-HR axis as a central driver of 5FU resistance, proposing therapeutic targeting of this pathway to overcome CRC chemoresistance.
Liu Y, Fu C, He L, Tokulabc S, Zhang H, Liu Q, Song Q.
Periplaneta Americana polysaccharides promote and maintain the M2 polarization of macrophages through the O-GlcNAc-HIF-1α/PPARγ pathway.
International immunopharmacology2026
171
41483621
Abstract: Previous studies have found that the active polysaccharide PAP55-3-1 from Periplaneta americana promotes the expression of HIF-1α in macrophage RAW264.7 cells, induces M2 polarization of macrophages, and maintains the M2 phenotype even under H2O2 stimulation, thereby reducing the inflammatory response and promoting wound healing. This study aims to further investigate the molecular mechanisms underlying the anti-inflammatory effects of PAP55-3-1. Untargeted metabolomics revealed that PAP55-3-1 promotes the HBP pathway, thereby enhancing the O-GlcNAcylation of total protein and HIF-1α. Meanwhile, PAP55-3-1 also stabilizes HIF-1α by promoting O-GlcNAcylation. Through mass spectrometry analysis, three specific O-GlcNAc modification sites (T241, S244, and S247) within the PAS domain of HIF-1α were identified for the first time. Site-directed mutagenesis revealed that O-GlcNAcylation at these sites enhances PPARγ transcription, thereby promoting lipid synthesis and M2 polarization of macrophages. Since all three modification sites are located within the PAS domain, it is hypothesized that the maintenance of HIF-1α stability may be mediated by other mechanisms. This study reveals that PAP55-3-1 promotes and sustains the M2 macrophage via the O-GlcNAc-HIF-1α/PPARγ axis. Furthermore, O-GlcNAcylation at T241, S244, and S247 residues of HIF-1α represents key molecular targets through which Periplaneta americana polysaccharides facilitate wound healing.
Gao X, Liu H, Guo J, Li G, Yang X, Peng X, Ren Y, Sun X, Liang C, Du Y.
Ogt-mediated KDM6B O-GlcNAcylation regulates histone demethylation and alleviates osteoarthritis.
Journal of advanced research202641485575
Abstract: Osteoarthritis (OA) is a common orthopedic disease characterized by cartilage degeneration, osteophyte formation, and synovial hyperplasia. Although dysregulated O-GlcNAcylation has been implicated in various musculoskeletal and inflammatory disorders, its specific role and molecular targets in OA pathogenesis remain largely unexplored. In this study, we aimed to conduct a multidimensional investigation to demonstrate and delineate the chondrocyte-specific functions and mechanisms of O-GlcNAc transferase (OGT) during OA progression.
Wang Q, Liu Y, Wang K, Huang A, Tang N, Peng P.
O-GlcNAcylation of DDX46 promotes hepatocellular carcinoma progression by activating the PI3K/Akt signaling pathway.
Biochimica et biophysica acta. Molecular cell research2026
1873(1)
41176131
Abstract: O-linked-β-N-acetylglucosamine (O-GlcNAc) modification, also known as O-GlcNAcylation, is a dynamic and reversible protein modification. Aberrant O-GlcNAcylation are associated with the pathogenesis of cancers. DEAD-box helicase 46 (DDX46) is an ATP-dependent RNA helicase associated with cancer development; however, its role and regulation in hepatocellular carcinoma (HCC) remain unclear. In this study, we observed that the level of O-GlcNAcylation of DDX46 was significantly elevated in HCC mouse models and patients. In addition, direct OGT-DDX46 interaction facilitates O-GlcNAcylation at the Ser257 site. Mechanically, we discovered that O-GlcNAcylation enhances the stability of DDX46 by impeding ubiquitin-mediated degradation. Increased expression of DDX46 activates the PI3K/Akt signaling pathway, promoting the proliferation and invasion of HCC. Taken together, our study highlights the critical role of DDX46 O-GlcNAcylation in HCC progression, thus proposing targeted disruption of this cascade as a novel therapeutic strategy for HCC treatment.
Chen Q, Cheng W, Li C, Fung YME, Wang J, Liu H, Li X.
Higher-Energy Collisional Dissociation Mass Spectrometry Fragmentation Enables Distinguishing O-GlcNAc from Tn Antigen in Cancer Cells.
Journal of the American Society for Mass Spectrometry202641518202
Abstract: Protein glycosylation plays essential roles in various biological processes, and thus determining the glycan structure present on the protein is essential to comprehensively understand these events. However, distinguishing saccharide stereoisomers is challenging, especially when their structures are very similar and their molecular weight and potential glycosylation sites are identical. One representative example is O-linked β-N-acetylglucosamine (O-GlcNAc) and O-linked α-N-acetylgalactosamine (Tn antigen). Traditional biochemistry approaches used in separating O-GlcNAc- and Tn antigen-modified peptides mainly include chemical derivatizations, lectins, and antibodies. However, subsequent mass spectrometry (MS) analysis is still required if one aims to determine the exact glycosylation site. Herein, a straightforward approach using the ratio of relative abundance (RA) of two fragment ions (RA126.055/RA138.055) in higher-energy collisional dissociation (HCD) MS without relying on the traditional biochemistry technique is reported to discriminate between O-GlcNAc and Tn antigen. This ratio was verified by synthetic glycopeptides and proteomic analysis in HeLa cells, where 10 proteins were found to be O-GlcNAcylation and 4 proteins were found to be Tn antigen-modified. Overall, this method can be extensively employed in liquid chromatography-mass spectrometry (LC-MS)-based proteomic studies and thus is of importance in biological and biomedical research.
Zhang N, Zhao R, Zhong X, Dong Q, Liu Y, Yu K, Han L, Meng F, Wu J, Chen Q, Li X, Chen Q, Zhang K, Huang H, Zhang J, Wu S, Ren Y, Wang W, Liu Y.
Time-resolved multiomics profiling reveals chromatin O-GlcNAc modification promotes senescence-associated transcriptional program.
Nature communications202641507163
Abstract: O-GlcNAc modification is a key cellular signal, but its role in regulating senescence-associated transcription remains poorly understood. Here, we apply a time-resolved chemical genomics strategy to map dynamic O-GlcNAc chromatin-associated proteins (OCPs) during oncogene-induced senescence (OIS) in primary human fibroblasts. Chromatin O-GlcNAc modification continues to accumulate, while 1,987 senescence-associated OCPs undergo dynamic shifts in genomic occupancy across diverse epigenetic chromatin states and display bimodal regulatory activities within the 3,466-gene senescence transcriptome. O-GlcNAc facilitates the formation of dual-function complexes: TF-SWI/SNF activates senescence-associated secretory phenotype (SASP) genes at promoters, whereas NuRD enforces the repression of cell-cycle regulators at enhancers. Furthermore, we identify O-GlcNAc modified JUN and GATAD2A as key regulators of OIS phenotypes in both in vitro and in vivo models of senescence-driven tumorigenesis. These findings reveal dynamic regulation and chromatin organization principles of O-GlcNAc-related epigenetic factors, providing insights into cellular senescence and potential therapeutic strategies.
Wang Y, Zhou X, Zhang Y, Yang F, Chen Y, Wu Y, Zhang L, Tan J, Luo W, Zhou J, Yan Y.
OGT-enriched hepatocyte-derived extracellular vesicles promote capillarization of liver sinusoidal endothelial cells in metabolic dysfunction-associated steatotic liver disease.
Cellular and molecular gastroenterology and hepatology202641513003
Abstract: The global incidence of metabolic dysfunction-associated steatotic liver disease (MASLD) has risen dramatically. The capillarization of liver sinusoidal endothelial cells (LSEC) represents a crucial target for intervention in MASLD. However, the regulatory mechanisms underlying LSEC capillarization in MASLD remain unclear. Angiopoietin-2 (Ang-2) serves as a key regulator of vascularization.
Vanauberg D, Schulz C, Brysbaert G, Raouraoua N, Mistarz-Gruau P, Lensink MF, Vercoutter-Edouart AS, Lefebvre T.
Mammalian fatty acid synthase and O-GlcNAc transferase preferentially interact via their respective N-terminal regions.
Biochemistry and biophysics reports2026
45
41550490
Abstract: Fatty Acid Synthase (FASN) is a central enzyme in the de novo lipogenesis pathway. By producing fatty acids, FASN is implicated in numerous crucial cellular processes, but it is also frequently overexpressed in cancer. O-GlcNAc Transferase (OGT) governs the addition of N-acetylglucosamine residues onto cytosolic, nuclear and mitochondrial proteins. Like FASN, OGT actively participates in carcinogenesis. We previously showed that OGT regulates FASN in different ex vivo and in vivo models. Reciprocally, FASN promotes OGT expression and activity. The two enzymes physically interact together and contribute to cancer cell survival. It is therefore fundamental to define the respective interaction region of each enzyme to explore new therapeutic solutions for patients suffering from cancer. By using the hepatocarcinoma cell line Hep3B, we show thanks to two series of deletion mutants that both enzymes preferentially interact via their respective N-terminal regions. Analysis of the O-GlcNAc status of the various FASN deletion mutants shows that stronger interaction with OGT correlates with higher glycosylation, suggesting that OGT catalyzes the transfer of GlcNAc with limited substrate specificity.
Wen L, Dai R, Yu S, Yu H.
OGT-mediated O-GlcNAcylation of MAGI1 exacerbates high glucose-triggered inflammation and dedifferentiation of vascular smooth muscle cells by activating the PI3K/AKT pathway.
Hereditas202641546072
Shan S, Chen W, Wu W, Zhang W, Liu J, Liao W, Wen Y, Zhao C.
Green Alga Enteromorpha prolifera Oligosaccharide Exerts Antiaging Effects through Targeted Modulation of Protein O-GlcNAcylation.
Journal of agricultural and food chemistry202641549750
Abstract: Aging and diabetes are intricately linked, with metabolic dysregulation playing a pivotal role in the pathophysiology of both conditions. This study investigates the therapeutic potential of Enteromorpha prolifera oligosaccharide (EPO) in mitigating aging-related metabolic decline through modulation of O-GlcNAcylation. The results demonstrate that EPO treatment significantly reduced O-GlcNAc levels, thereby attenuating ROS accumulation and alleviating cell cycle arrest to counteract aging-associated metabolic decline. Specifically, shOGA increased ROS by 77.0% and induced G2/M arrest (12.2%). These alterations were mimicked by TMG but reversed by EPO, identifying OGA as the primary driver of ROS generation and cell cycle regulation. shHCF1 decreased ROS (48.8% to 28.3%), G0/G1 (59.7%), and S phase (6.6%) but increased G2/M to 30.9%, suggesting ROS attenuation alongside G2/M arrest. Overall, this research highlights the role of EPO in regulating key cellular processes, providing new insights for the development of antiaging therapies.
Moniaux N, Geoffre N, Deshayes A, Dos Santos A, Job S, Lacoste C, Nguyen TS, Darnaud M, Friedel-Arboleas M, Guettier C, Purhonen J, Kallijärvi J, Amouyal G, Amouyal P, Bréchot C, Vivès RR, Buendia MA, Issad T, Faivre J.
Tumor suppressive role of the antimicrobial lectin REG3A targeting the O -GlcNAc glycosylation pathway.
Hepatology (Baltimore, Md.)2025
81(5)
38975812
Abstract: Antimicrobial proteins of the regenerating family member 3 alpha (REG3A) family provide a first line of protection against infections and transformed cells. Their expression is inducible by inflammation, which makes their role in cancer biology less clear since an immune-inflammatory context may preexist or coexist with cancer, as occurs in HCC. The aim of this study is to clarify the role of REG3A in liver carcinogenesis and to determine whether its carbohydrate-binding functions are involved.
Liang Y, Chen L, Huang Z, Li Y, Weng H, Guo L.
O-GlcNAcylation of progranulin promotes hepatocellular carcinoma proliferation.
Biochemical and biophysical research communications2025
742
39657353
Abstract: Progranulin (PGRN) is overexpressed and implicated in hepatocellular carcinoma (HCC) development; however, its post-translational modifications and regulatory mechanisms in HCC remain largely unexplored. Here, the expression levels of PGRN, OGT, and O-GlcNAcylation were found to be elevated in both HCC samples and cell lines. LC-MS/MS analysis and immunoprecipitation revealed that PGRN underwent O-linked N-acetylglucosamine (O-GlcNAc) modification at threonine 272 (Thr272). Co-immunoprecipitation and confocal microscopy confirmed the interaction and colocalization of O-GlcNAc transferase (OGT) with PGRN. Reducing O-GlcNAcylation increased the ubiquitination of PGRN, while increasing O-GlcNAcylation inhibited ubiquitination and elevated PGRN stability, as measured by cycloheximide (CHX) chase experiments. This regulation of PGRN stability was directly linked to its expression levels. Moreover, mutation at the primary O-GlcNAc site Thr272 inhibited the activity of the PI3K/AKT/mTOR signaling pathway and suppressed HCC cell proliferation. Together, our findings indicate that O-GlcNAcylation at Thr272 is essential for PGRN-driven HCC cell proliferation.
Li J, Shao G, Peng B, Xu X, Dong MQ, Li J.
The Role of Polo-Like Kinase 1 (PLK1) O-GlcNAcylation in Mitosis.
Methods in molecular biology (Clifton, N.J.)2025
2874
39614052
Abstract: Polo-like kinase 1 (PLK1) is a crucial mitotic kinase that is implicated in various aspects of cell cycle. Many post-translational modifications have been identified on PLK1 to regulate its activation, stability, and localization. PLK1 has been shown previously to colocalize with the O-linked β-N-acetylglucosamine (O-GlcNAc) transferase (OGT), and OGT regulates PLK1 stability. In our recent work, we show that PLK1 is O-GlcNAcylated by click chemistry. Using stepped collisional energy/higher energy collision dissociation mass spectrometry, we mapped the PLK1 O-GlcNAc site to be T291. We further utilized fluorescent activated cell sorting and time-lapse microscopy to assess the mitotic defects of PLK1 O-GlcNAc mutants. In vivo studies in mouse xenograft demonstrated that it promoted uterine cancer tumorigenesis. In this chapter, we delineate the methodologies we used in studying PLK1 O-GlcNAcylation, including click chemistry, stepped collisional energy/higher energy collision dissociation mass spectrometry, fluorescent activated cell sorting, time-lapse microscopy, and mouse xenograft assays.
Jeon BC, Kim YJ, Park AK, Song MR, Na KM, Lee J, An D, Park Y, Hwang H, Kim TD, Lim J, Park SK.
Dynamic O-GlcNAcylation governs long-range chromatin interactions in V(D)J recombination during early B-cell development.
Cellular & molecular immunology2025
22(1)
39627609
Abstract: V(D)J recombination secures the production of functional immunoglobulin (Ig) genes and antibody diversity during the early stages of B-cell development through long-distance interactions mediated by cis-regulatory elements and trans-acting factors. O-GlcNAcylation is a dynamic and reversible posttranslational modification of nuclear and cytoplasmic proteins that regulates various protein functions, including DNA-binding affinity and protein-protein interactions. However, the effects of O-GlcNAcylation on proteins involved in V(D)J recombination remain largely unknown. To elucidate this relationship, we downregulated O-GlcNAcylation in a mouse model by administering an O-GlcNAc inhibitor or restricting the consumption of a regular diet. Interestingly, the inhibition of O-GlcNAcylation in mice severely impaired Ig heavy-chain (IgH) gene rearrangement. We identified several factors crucial for V(D)J recombination, including YY1, CTCF, SMC1, and SMC3, as direct targets of O-GlcNAc modification. Importantly, O-GlcNAcylation regulates the physical interaction between SMC1 and SMC3 and the DNA-binding patterns of YY1 at the IgH gene locus. Moreover, O-GlcNAc inhibition downregulated DDX5 protein expression, affecting the functional association of CTCF with its DNA-binding sites at the IgH locus. Our results showed that locus contraction and long-range interactions throughout the IgH locus are disrupted in a manner dependent on the cellular O-GlcNAc level. In this study, we established that V(D)J recombination relies on the O-GlcNAc status of stage-specific proteins during early B-cell development and identified O-GlcNAc-dependent mechanisms as new regulatory components for the development of a diverse antibody repertoire.
Du Y, Gao X, Chen J, Chen X, Liu H, He W, Liu L, Jiang Y, He B, Deng Z, Liang C, Guo F.
OGT mediated HDAC5 O-GlcNAcylation promotes osteogenesis by regulating the homeostasis of epigenetic modifications and proteolysis.
Journal of orthopaedic translation2025
50
39659899
Abstract: O-GlcNAc transferase (OGT) is responsible for attaching O-linked N-acetylglucosamine (O-GlcNAc) to proteins, regulating diverse cellular processes ranging from transcription and translation to signaling and metabolism. This study focuses on the role and mechanisms of OGT in osteogenesis.
Qiu Y, Yu W, Zhang X, Zhang M, Ni Y, Lai S, Wu Q.
Upregulation of OGT-mediated EZH2 O-GlcNAcylation Promotes Human Umbilical Vein Endothelial Cell Proliferation, Invasion, Migration, and Tube Formation in Gestational Diabetes Mellitus.
Cell biochemistry and biophysics202539751742
Abstract: O-linked N-acetylglucosamine transferase (OGT)-catalyzed O-linked N-acetylglucosamine glycosylation (O-GlcNAcylation) is closely associated with diabetes progression. This study aims to investigate the mechanism of OGT in regulating endothelial dysfunction in gestational diabetes mellitus (GDM). Expressions of OGT, O-linked N-acetylglucosamine (O-GlcNAc), enhancer of zeste homolog 2 (EZH2), and HEK27me3 in human umbilical vein endothelial cells (HUVECs) and GDM-derived HUVECs (GDM-HUVECs) were assessed by western blot. RT-qPCR and western blot assays were used to test the OGT overexpression and EZH2 silencing levels. CCK-8, EdU, wound healing, and transwell invasion assays were used to analyze the cell proliferative, migratory, and invasive abilities. Tube formation assay was performed to evaluate angiogenesis ability of cells. Western blot assay was performed to estimate vascular endothelial growth factor (VEGF) and p-VEGFR2 levels in cells. The binding of O-GlcNAc and EZH2 after OGT overexpression was measured by Co-IP assay. The results showed that OGT, O-GlcNAc, EZH2, and HEK27me3 expressions were declined in GDM-HUVECs. OGT overexpression induced the proliferation, migration, and invasion of GDM-HUVECs, and also elevated angiogenesis and the expressions of VEGF and p-VEGFR2 in cells. O-GlcNAc, EZH2, and HEK27me3 expressions were upregulated after OGT overexpression. OGT upregulation induced the binding between O-GlcNAc and EZH2. EZH2 silencing attenuated the promotion of OGT overexpression on the proliferative, invasive, migratory, and angiogenic capacities of GDM-HUVECs. To be concluded, OGT overexpression stabilized EZH2 expression by promoting O-GlcNAcylation modification of EZH2, and further enhanced proliferation, migration, and invasion as well as angiogenesis of GDM-HUVECs. While these effects were decayed after EZH2 absenting. Overall, the modulation of OGT on endothelial dysfunction in GDM provides a novel perspective for the clinical treatment of GDM.
Sitosari H, Fukuhara Y, Weng Y, Zheng Y, He Y, Zheng X, Ikegame M, Okamura H.
High Glucose Inhibits O-GlcNAc Transferase Translocation in Early Osteoblast Differentiation by Altering Protein Phosphatase 2A Activity.
Journal of cellular physiology2025
240(1)
39800889
Abstract: Our previous study revealed a link between O-GlcNAc transferase (OGT) localization and protein phosphatase 2A (PP2A) activity in osteoblast. Given the association of PP2A downregulation with osteoblast differentiation, we hypothesized that OGT localization changes during this process. We examined OGT localization in MC3T3-E1 cells undergoing differentiation under normal and high glucose conditions. Changes in PP2A activity were followed by alterations in OGT localization. Organ culture of calvaria revealed similar OGT localization changes in bone-surrounding osteoblasts near the suture area. Furthermore, the levels of O-GlcNAc modification in various proteins including Runt-related transcription factor 2, Osterix, and ATP synthase subunit alpha (ATP5A) were shifted in parallel with OGT translocation. These findings suggest a regulatory role of OGT, under the influence of PP2A, during osteoblast differentiation.
Zhou X, Yang Y, Qiu X, Deng H, Cao H, Liao T, Chen X, Huang C, Lin D, Ni G.
Antioxidant taurine inhibits chondrocyte ferroptosis through upregulation of OGT/Gpx4 signaling in osteoarthritis induced by anterior cruciate ligament transection.
Journal of advanced research202539778769
Abstract: The aim of this study was to investigate the potential molecular mechanisms by which taurine protects against cartilage degeneration.
Yan Z, Li Y, Wang M, Xu K, Liu Y, Wang L, Luo H, Chen Z, Liu X.
O-GlcNAcylation of DJ-1 suppresses ferroptosis in renal cell carcinoma by affecting the transsulfuration pathway.
International immunopharmacology2025
148
39842141
Abstract: Renal cell carcinoma (RCC) is one of the most common urological malignancies worldwide, and advanced patients often face challenges with chemotherapy resistance and poor prognosis. Ferroptosis, a novel form of cell death, offers potential therapeutic prospects. In this study, we found that DJ-1 was elevated in kidney renal clear cell carcinoma (KIRC), and this abnormal expression pattern was closely associated with clinical pathological characteristics and worse prognosis. Our experiments both in vivo and in vitro revealed that DJ-1 enhanced the malignant characteristics of KIRC, leading to increased tumor growth. Additionally, DJ-1 inhibited ferroptosis through promoting homocysteine (Hcy) synthesis in the transsulfuration pathway in KIRC cells. Mechanistic studies revealed that O-GlcNAc transferase (OGT) mediated O-GlcNAcylation of DJ-1 was crucial for maintaining its homodimeric structure. Importantly, O-GlcNAcylation-deficient mutation of DJ-1 at T19 residue enhanced the interaction between S-adenosyl homocysteine hydrolase (SAHH) and the negative regulatory factor S-adenosyl homocysteine hydrolase-like-1 (AHCYL1), thereby inhibited the activities of SAHH and transsulfuration pathway. In summary, the oncogenic role of DJ-1 in KIRC was closely related to the reduction of ferroptosis, and the O-GlcNAcylation of DJ-1 exerted an antioxidant effect by activating the transsulfuration pathway. Therefore, DJ-1, specifically O-GlcNAcylation of DJ-1 could represent an important target for ferroptosis-based anti-tumor therapy.
Gou J, Bi J, Wang K, Lei L, Feng Y, Tan Z, Gao J, Song Y, Kang E, Guan F, Li X.
O-GlcNAcylated FTO promotes m6A modification of SOX4 to enhance MDS/AML cell proliferation.
Cell communication and signaling : CCS2025
23(1)
39849461
Abstract: Fat mass and obesity-associated protein (FTO) was the first m6A demethylase identified, which is responsible for eliminating m6A modifications in target RNAs. While it is well-established that numerous cytosolic and nuclear proteins undergo O-GlcNAcylation, the possibility of FTO being O-GlcNAcylated and its functional implications remain unclear. This study found that a negative correlation between FTO expression and O-GlcNAcylation in patients with myelodysplastic syndrome (MDS) and acute myeloid leukemia (AML). The decreased O-GlcNAcylation on FTO can result in diminished m6A modification of SRY-related high mobility group box 4 (SOX4). This led to the promotion of cell apoptosis and inhibition of cell proliferation in MDS/AML. The O-GlcNAcylation of FTO stabilized SOX4 transcripts in an m6A-dependent manner, resulting in increased AKT and MAPK phosphorylation and decreased cell apoptosis. Inhibiting FTO O-GlcNAcylation significantly slowed AML progression in vitro, a finding supported by clinical data in MDS/AML patients. In conclusion, our study highlights the crucial role of FTO O-GlcNAcylation in RNA m6A methylation and the progression of MDS/AML, thereby providing a potential therapeutic avenue for these formidable diseases.
Rodrigues BDC, Dos Santos Lucena MC, Costa ACR, Oliveira IA, Thaumaturgo M, Paes-Colli Y, Beckman D, Ferreira ST, de Mello FG, De Melo Reis RA, Todeschini AR, Dias WB.
O-GlcNAcylation regulates tyrosine hydroxylase serine 40 phosphorylation and L-DOPA levels.
American journal of physiology. Cell physiology202539870381
Abstract: O-GlcNAcylation is a post-translational modification characterized by the covalent attachment of a single moiety of GlcNAc on serine/threonine residues in proteins. Tyrosine hydroxylase (TH), the rate-limiting step enzyme in the catecholamine synthesis pathway and responsible for production of the dopamine precursor, L-DOPA, has its activity regulated by phosphorylation. Here, we show an inverse feedback mechanism between O-GlcNAcylation and phosphorylation of TH at serine 40 (TH pSer40). First, we showed that, during PC12 cells neuritogenesis, TH O-GlcNAcylation decreases concurrently with the increase of pSer40. In addition, an increase in O-GlcNAcylation induces a decrease in TH pSer40 only in undifferentiated PC12 cells, while the decrease in O-GlcNAcylation leads to an increase in TH pSer40 levels in both undifferentiated and differentiated PC12 cells. We further show that this feedback culminates on the regulation of L-DOPA intracellular levels. Interestingly, it is noteworthy that decreasing O-GlcNAcylation is much more effective on TH pSer40 regulation than increasing its levels. Finally, ex vivo analysis confirmed the upregulation of TH pSer40 when O-GlcNAcylation levels are reduced in dopaminergic neurons from C57Bl/6 mice. Taken together, these findings demonstrate a dynamic control of L-DOPA production by a molecular crosstalk between O-GlcNAcylation and phosphorylation at Ser40 in tyrosine hydroxylase.
Zuo Y, Wang Q, Tian W, Zheng Z, He W, Zhang R, Zhao Q, Miao Y, Yuan Y, Wang J, Zheng H.
β-hydroxybutyrylation and O-GlcNAc modifications of STAT1 modulate antiviral defense in aging.
Cellular & molecular immunology202539979583
Abstract: Aging changes the protein activity status to affect the body's functions. However, how aging regulates protein posttranslational modifications (PTMs) to modulate the antiviral defense ability of the body remains unclear. Here, we found that aging promotes STAT1 β-hydroxybutyrylation (Kbhb) at Lys592, which inhibits the interaction between STAT1 and type-I interferon (IFN-I) receptor 2 (IFNAR2), thereby attenuating IFN-I-mediated antiviral defense activity. Additionally, we discovered that a small molecule from a plant source, hydroxy camptothecine, can effectively reduce the level of STAT1 Kbhb, thus increasing antiviral defense ability in vivo. Further studies revealed that STAT1 O-GlcNAc modifications at Thr699 block CBP-induced STAT1 Kbhb. Importantly, fructose can improve IFN-I antiviral defense activity by orchestrating STAT1 O-GlcNAc and Kbhb modifications. This study reveals the significance of the switch between STAT1 Kbhb and O-GlcNAc modifications in regulating IFN-I antiviral immunity during aging and provides potential strategies to improve the body's antiviral defense ability in elderly individuals.
Jaiswal R, Liu Y, Petriello M, Zhang X, Yi Z, Fehl C.
A reference dataset of O-GlcNAc proteins in quadriceps skeletal muscle from mice.
Glycobiology2025
35(3)
39927985
Abstract: A key nutrient sensing process in all animal tissues is the dynamic attachment of O-linked N-acetylglucosamine (O-GlcNAc). Determining the targets and roles of O-GlcNAc glycoproteins has the potential to reveal insights into healthy and diseased metabolic states. In cell studies, thousands of proteins are known to be O-GlcNAcylated, but reference datasets for most tissue types in animals are lacking. Here, we apply a chemoenzymatic labeling study to compile a high coverage dataset of quadriceps skeletal muscle O-GlcNAc glycoproteins from mice. Our dataset contains over 550 proteins, and > 80% of the dataset matched known O-GlcNAc proteins. This dataset was further annotated via bioinformatics, revealing the distribution, protein interactions, and gene ontology (GO) functions of these skeletal muscle proteins. We compared these quadriceps glycoproteins with a high-coverage O-GlcNAc enrichment profile from mouse hearts and describe the key overlap and differences between these tissue types. Quadriceps muscles can be used for biopsies, so we envision this dataset to have potential biomedical relevance in detecting aberrant glycoproteins in metabolic diseases and physiological studies. This new knowledge adds to the growing collection of tissues with high-coverage O-GlcNAc profiles, which we anticipate will further the systems biology of O-GlcNAc mechanisms, functions, and roles in disease.
Rucli S, Descostes N, Ermakova Y, Chitnavis U, Couturier J, Boskovic A, Boulard M.
Functional genomic profiling of O-GlcNAc reveals its context-specific interplay with RNA polymerase II.
Genome biology2025
26(1)
40128797
Abstract: How reversible glycosylation of DNA-bound proteins acts on transcription remains scarcely understood. O-linked β-N-acetylglucosamine (O-GlcNAc) is the only known form of glycosylation modifying nuclear proteins, including RNA polymerase II (RNA Pol II) and many transcription factors. Yet, the regulatory function of the O-GlcNAc modification in mammalian chromatin remains unclear.
Liu Z, Yuan J, Din MA, Tian Y, Mao F.
HucMSC-Ex alleviates inflammatory bowel disease by regulating O-GlcNAcylation modification of RACK1 in intestinal epithelial cells.
Colloids and surfaces. B, Biointerfaces2025
251
40068238
Abstract: Inflammatory Bowel Disease (IBD) is a chronic autoimmune disorder that severely affects the gastrointestinal tract and is difficult to cure. This study explored the mechanism by which human umbilical cord mesenchymal stem cell-derived exosomes (HucMSC-Ex) alleviate IBD through O-GlcNAc glycosylation modification and the expression of related proteins. The study analyzed the effects of HucMSC-Ex on the inhibition of pro-inflammatory factors and promotion of intestinal epithelial cells regeneration in vitro and in vivo, with a focus on the role of the O-GlcNAc glycosylation of the RACK1 protein. The findings indicated that HucMSC-Ex reverses epithelial-mesenchymal transition (EMT) by upregulating O-GlcNAc glycosylation levels and effectively alleviates IBD symptoms and inflammatory responses in mouse intestinal epithelial cells. By modulating O-GlcNAc glycosylation, HucMSC-Ex exhibits significant therapeutic potential in immune regulation and gut microbiota remodeling, offering new perspectives for IBD treatment.