| 2000 |
GP73/GOLM1 is an integral membrane protein localized to the Golgi apparatus, as determined by in vitro transcription-translation studies and immunolocalization experiments using epitope-tagged GP73; it is preferentially expressed by epithelial cells and is normally absent from hepatocytes but upregulated in response to viral infection. |
In vitro transcription-translation, epitope-tag immunolocalization, Northern blot, immunohistochemistry |
Gene |
High |
10831838
|
| 2002 |
GP73 expression is upregulated at the RNA and protein level by adenovirus infection, and this induction requires the CtBP interaction domain (CID) of the adenoviral E1A protein, as demonstrated by infection with a panel of E1A mutant adenoviruses and transient transfection of wild-type vs. mutant E1A constructs. |
RNase protection assay, immunoblotting, immunofluorescence, infection with mutant adenoviruses, transient transfection of E1A mutants |
Virology |
High |
12359426
|
| 2007 |
Soluble GP73 is released from cells by proprotein convertase (furin)-mediated cleavage of its ectodomain. GP73 traffics from the cis-Golgi to the trans-Golgi network and endosomes, and cleavage occurs at a PC consensus site in the endosomal compartment. Alanine substitutions in the PC consensus site blocked both in vitro and in vivo cleavage, establishing the mechanism of GP73 secretion into serum. |
In vitro cleavage assay with purified furin, site-directed alanine mutagenesis, cleavage-specific antibody, subcellular fractionation/immunofluorescence of endosomes |
Traffic |
High |
17662025
|
| 2008 |
At least two of three potential N-linked glycosylation sites on GP73 are occupied; the major glycoforms on secreted GP73 are bi-antennary with core fucose, with a smaller fraction of tri- and tetra-antennary structures, and approximately three-quarters of secreted GP73 is fucosylated, as determined by lectin affinity chromatography and mass spectrometry. |
Lectin affinity chromatography, mass spectrometry, recombinant GP73 expression |
Journal of cellular biochemistry |
High |
18004786
|
| 2008 |
C-terminal truncation of GP73 in mice (gene-trap approach generating GP73^tr/tr) causes reduced survival, focal segmental glomerulosclerosis, hyaline thrombi in kidneys, and microvesicular hepatic steatosis with nuclear membrane irregularities, indicating that the GP73 C-terminus is essential for normal epithelial cell function in kidney and liver. |
Gene trap mouse model, histopathology, immunohistochemistry |
International journal of clinical and experimental pathology |
Medium |
18830387
|
| 2010 |
The Golgi localization of GOLPH2/GOLM1 is determined by its transmembrane domain combined with a positively charged residue in the cytoplasmic N-terminal tail; the C-terminal luminal domain is dispensable for Golgi targeting. Additionally, both endogenous and secreted GOLPH2 exist as disulfide-bonded dimers, and the coiled-coil domain is sufficient for dimerization. |
Truncation mutant panel, immunofluorescence microscopy, non-reducing SDS-PAGE, domain deletion analysis |
PloS one |
High |
22140547
|
| 2010 |
GOLPH2/GOLM1 interacts with secretory clusterin (sCLU); the coiled-coil domain of GOLPH2 is sufficient for binding to sCLU, confirmed by yeast two-hybrid screening, intracellular co-immunoprecipitation, and co-localization in the Golgi. |
Yeast two-hybrid, co-immunoprecipitation, co-localization by immunofluorescence |
Molecular biology reports |
Medium |
20842452
|
| 2012 |
IL-6 and oncostatin M (OSM) upregulate GP73 mRNA and protein in hepatoma (HepG2) cells via the shared receptor subunit gp130 and correlate with increased STAT3 phosphorylation; maximal induction requires new protein synthesis, suggesting indirect transcriptional regulators are involved. |
Cytokine treatment of HepG2 cells, Western blot, STAT3 phosphorylation analysis, protein synthesis inhibition with cycloheximide |
Cancer biomarkers |
Medium |
23144154
|
| 2012 |
The GOLPH2/GOLM1 promoter (2599 bp fragment) is TATA-less and maintains epithelial specificity. A repressive region (−864 to −734 bp), a positive regulatory region (−734 to −421 bp), and a core promoter region (−421 to −79 bp) were identified by deletion analysis. Adenoviral E1A activates GOLPH2 via its CtBP interaction domain; a GC-box motif (−89 to −83 bp) in the core promoter partly mediates E1A transactivation. |
Promoter cloning, deletion analysis, luciferase reporter assay, E1A transient transfection |
Biochemical and biophysical research communications |
Medium |
22542941
|
| 2014 |
Epithelium-specific ETS transcription factor ESE-1 directly binds the GP73 promoter and activates GP73 transcription. Both ESE-1 and GP73 are co-induced by IL-1β in hepatocellular carcinoma cells and during liver inflammation in vivo; knockdown of ESE-1 reduces GP73 expression. |
Promoter reporter assay, ChIP (direct binding to GP73 promoter), siRNA knockdown, overexpression, in vivo liver inflammation model |
Cell & bioscience |
Medium |
25530841
|
| 2014 |
GP73 enhances HCV secretion through its coiled-coil domain and by interacting with apolipoprotein E (ApoE), a host factor required for HCV secretion; GP73 overexpression or knockdown had no effect on HCV entry, protein translation, RNA replication, or assembly, placing GP73 specifically in the secretion step. |
Co-immunoprecipitation (GP73-ApoE interaction), GP73 overexpression/knockdown in HCV replicon and infected cell systems, domain deletion (coiled-coil mutant) |
PloS one |
Medium |
24608522
|
| 2015 |
mTORC1 positively regulates GP73 expression in HCC and other cancer cell lines; rapamycin (mTORC1 inhibitor) reduces GP73 levels in cancer cell lines and in xenograft tumors. GP73 overexpression promotes HCC cell proliferation and migration in vitro and accelerates xenograft tumor growth and metastasis in mice; GP73 knockout mice show reduced liver damage after diethylnitrosamine administration. |
Retroviral GP73 overexpression, shRNA knockdown, GP73 knockout mice, xenograft mouse models, rapamycin treatment, microarray gene expression, PTEN-null MEFs with constitutively active mTOR |
Gastroenterology |
High |
25980751
|
| 2016 |
GOLM1 selectively interacts with EGFR and other RTKs and functions as a cargo adaptor to anchor EGFR/RTKs on the trans-Golgi network (TGN) and recycle them back to the plasma membrane, leading to prolonged downstream kinase activation and promoting HCC metastasis. |
Co-immunoprecipitation (GOLM1-EGFR interaction), gain- and loss-of-function studies, RTK recycling assays, gene expression profiling of HCC tissues |
Cancer cell |
High |
27569582
|
| 2016 |
N-glycosylation of GP73 at Asn144 reduces hepatocellular carcinoma cell motility and invasiveness; removal of N-glycans at Asn144 by site-directed mutagenesis enhances cell migration and invasion, possibly by altering cell membrane glycosylation and cell adhesion. Three N-glycosylation sites were identified (Asn109, Asn144, Asn398) by mass spectrometry, with five glycoforms at Asn144. |
Mass spectrometry for glycosylation site mapping, lectin microarray, site-directed mutagenesis of Asn144, cell migration and invasion assays |
Oncotarget |
High |
26993603
|
| 2017 |
GP73 acts as a negative regulator of innate immunity to facilitate HCV infection: upon HCV infection, MAVS recruits TRAF6 via TRAF-interacting motifs; TRAF6 then directly recruits GP73 to MAVS via GP73's coiled-coil domain. GP73 then promotes proteasome-dependent degradation of both MAVS and TRAF6, attenuating IFN-β and NF-κB signaling. |
Co-immunoprecipitation (GP73-MAVS, GP73-TRAF6), domain mapping (coiled-coil deletion), proteasome inhibitor experiments, IFN-β/NF-κB reporter assays, GP73 knockdown in primary human hepatocytes and Huh7 cells, rescue with shRNA-resistant GP73 mutant |
PLoS pathogens |
High |
28394926
|
| 2017 |
GOLM1 promotes prostate cancer progression by activating the PI3K-AKT-mTOR signaling pathway; PI3K inhibitor BKM120 abrogates GOLM1's oncogenic effects on proliferation, migration, invasion, and apoptosis in PCa cell lines and xenograft models. |
GOLM1 overexpression and knockdown in PCa cell lines, xenograft mouse models, PI3K inhibitor treatment, Western blot for AKT/mTOR pathway components |
The Prostate |
Medium |
29181846
|
| 2017 |
PDGFA/PDGFRα signaling regulates GOLM1 expression; GOLM1 in turn promotes glioma progression through activation of AKT. GOLM1 is a key element in the PDGFA/PDGFRα-mediated AKT activation cascade, as demonstrated by PDGFRα inhibitor AG1296 and AKT inhibitor MK-2206 experiments. |
siRNA knockdown and lentiviral overexpression of GOLM1 in glioma cells, PDGFRα inhibitor (AG1296), AKT inhibitor (MK-2206), membrane-based kinase antibody array, orthotopic implantation in vivo |
Journal of experimental & clinical cancer research |
Medium |
29282077
|
| 2019 |
c-Myc transcriptionally activates GP73 in a mildly hypoxic microenvironment; GP73 then interacts with intracellular MMP-7 via its cytoplasmic domain and facilitates MMP-7 trafficking and secretion, promoting HCC cell metastasis. |
ChIP assay (c-Myc binding to GP73 promoter), co-immunoprecipitation (GP73-MMP-7), cytoplasmic domain interaction mapping, MMP-7 secretion assays, cell invasion assays |
Oncogenesis |
Medium |
31591387
|
| 2019 |
mTOR negatively regulates miR-145 expression; miR-145 directly inhibits GOLM1 by targeting its coding sequence. GOLM1-enriched exosomes activate the GSK-3β/MMP signaling axis in recipient cells, accelerating proliferation and migration. |
miR-145 target validation (luciferase reporter assay targeting CDS of GOLM1), exosome isolation and transfer assay, GSK-3β/MMP pathway analysis, in vivo mouse HCC model |
Journal of genetics and genomics |
Medium |
31186161
|
| 2019 |
GP73 is a direct transcriptional target of TGF-β1; upregulated GP73 inhibits TGF-β-Smad-mediated growth suppression while enhancing ERK/AKT signaling downstream of TGF-β1. Mechanistically, GP73 upregulates lipid rafts/caveolin-1, which mediates the switch from Smad to non-Smad TGF-β1 signaling. |
TGF-β1 reporter assay, GP73 overexpression/knockdown, Western blot for Smad and ERK/AKT phosphorylation, lipid raft isolation, caveolin-1 staining |
Biochimica et biophysica acta. Molecular cell research |
Medium |
30615900
|
| 2020 |
GOLM1 upregulates PD-L1 expression via the EGFR/STAT3 signaling pathway in HCC cells: GOLM1 enhances EGFR levels, which promotes STAT3 phosphorylation, which in turn increases PD-L1 transcription. |
GOLM1 overexpression/knockdown, Western blot for EGFR and p-STAT3, STAT3 inhibitor treatment, PD-L1 expression analysis |
American journal of cancer research |
Medium |
33294262
|
| 2021 |
GOLM1 promotes COP9 signalosome 5-mediated PD-L1 deubiquitination in HCC cells, stabilizing PD-L1, and suppresses Rab27b expression to increase transport of PD-L1 into exosomes. Exosomes containing PD-L1 from GOLM1-high HCC cells upregulate PD-L1 on macrophages, inducing CD8+ T cell suppression. |
Gain- and loss-of-function studies, co-culture assays with exosomes, Rab27b expression analysis, ubiquitination/deubiquitination assays, flow cytometry for CD8+ T cells |
Signal transduction and targeted therapy |
Medium |
34795203
|
| 2021 |
GOLM1 depletion in intestinal epithelial cells leads to aberrant Notch pathway activation, interfering with IEC differentiation, maturation, and lineage commitment. GOLM1-deficient mice are susceptible to mucosal inflammation and colitis-induced epithelial damage; pharmacological inhibition of Notch alleviates epithelial lesions in GOLM1-deficient mice, placing GOLM1 upstream of Notch equilibrium. |
GOLM1 knockout mice (colitis models), Notch pathway inhibition (gamma-secretase inhibitor), histopathology, marker gene expression analysis |
Signal transduction and targeted therapy |
Medium |
33850109
|
| 2021 |
GP73 is a Rab GTPase-activating protein (RabGAP) with TBC domain activity that regulates ApoB export from hepatocytes; liver-specific GP73-overexpressing mice develop non-obese NAFLD (intrahepatic lipid accumulation, insulin resistance, reduced body weight), a phenotype not recapitulated by a GAP-inactive GP73 mutant. Metformin inactivates the GAP activity of GP73 and alleviates this non-obese NAFLD phenotype. |
RabGAP activity assay, TBC-domain mutagenesis (GAP-inactive mutant), liver-specific GP73 transgenic mice, high-fat diet NAFLD comparison, metformin treatment, ApoB export assays |
Nature communications |
High |
34853313
|
| 2021 |
GOLM1 promotes liver fibrosis-induced PD-L1 upregulation and immune escape in HCC via the EGFR signaling pathway; GOLM1 levels are increased in fibrotic livers and hepatocyte-specific GOLM1 transgenic mice show decreased CD8+ T cell infiltration and increased PD-L1 in tumors during chemical carcinogenesis. EGFR inhibitors improve immunotherapy efficacy. |
Hepatocyte-specific GOLM1 transgenic mice, CCl4-induced fibrosis model, EGFR inhibitor treatment, immunohistochemistry for CD8+ T cells and PD-L1, EGFR pathway Western blot |
Cancer letters |
Medium |
33992711
|
| 2021 |
GP73 directly binds AFP and increases AFP secretion from HCC cells; extracellular GP73 independently promotes HCC cell proliferation and metastasis, and extracellular GP73 and AFP synergize to enhance HCC malignancy and drug resistance to sorafenib. |
Co-immunoprecipitation (GP73-AFP direct binding), GP73 overexpression/knockdown, AFP secretion assays, cell proliferation and metastasis assays, sorafenib resistance assay |
Oncogenesis |
Medium |
34650031
|
| 2021 |
GOLM1 overexpression enhances phosphorylation of p53 at Ser315 and inhibits p53 tetramer formation, reducing p53 tumor-suppressor function; this effect is associated with GOLM1-driven lung cancer aggressiveness as shown by phosphoproteomic analysis. |
Phosphoproteomics (phosphoprotein array), Western blot for p53 phospho-Ser315, p53 tetramer native gel assay, GOLM1 overexpression/knockdown, xenograft in vivo |
Cell death discovery |
Medium |
33649292
|
| 2022 |
Cholesterol suppresses GOLM1-dependent autophagic degradation of RTKs: GOLM1 mediates selective autophagy of RTKs by interacting with LC3 through an LC3-interacting region (LIR) motif, and this interaction is regulated by a cholesterol-mTORC1 axis. High cholesterol activates mTORC1 to suppress the LIR-LC3 interaction, switching GOLM1 from promoting RTK degradation to promoting RTK recycling. |
Co-immunoprecipitation (GOLM1-LC3), LIR motif mutagenesis, autophagic flux assays, cholesterol manipulation, mTORC1 inhibition, statin treatment in vivo with RTK inhibitors |
Cell reports |
High |
35443161
|
| 2022 |
GP73 functions as a glucogenic hormone: fasting induces GP73 secretion from multiple tissues; secreted GP73 stimulates hepatic gluconeogenesis through the cAMP/PKA signaling pathway. SARS-CoV-2 infection increases GP73 secretion, and GP73 antibody blockade inhibits excessive gluconeogenesis in SARS-CoV-2-infected mice and lowers fasting blood glucose. |
GP73 recombinant protein treatment of hepatocytes, cAMP/PKA pathway inhibitors, GP73-neutralizing antibody in mice, mouse-adapted SARS-CoV-2 infection model, fasting experiments in multiple tissues |
Nature metabolism |
High |
34992299
|
| 2024 |
ASGR1 (asialoglycoprotein receptor 1) directly binds GP73 and facilitates its lysosomal degradation; ASGR1 deficiency increases circulating GP73 levels. Elevated GP73 then interacts with BIP/GRP78 to activate endoplasmic reticulum stress, causing liver injury. GP73 neutralization attenuates ASGR1-deficiency-induced liver injuries. |
Co-immunoprecipitation (ASGR1-GP73, GP73-BIP), lysosomal degradation assays, ASGR1 knockout and overexpression in mice, GP73-neutralizing antibody rescue experiments, acetaminophen and CCl4 liver injury models |
Nature communications |
High |
38459023
|
| 2024 |
GP73 promotes HCC tumor angiogenesis by directly binding STAT3 and simultaneously enhancing GRP78-induced endoplasmic reticulum stress; GP73 is activated transcriptionally by histone lactylation and c-Myc, and GP73-mediated STAT3 phosphorylation potentiates pro-angiogenic functions. |
Co-immunoprecipitation (GP73-STAT3), ChIP for c-Myc and histone lactylation at GP73 locus, in vitro and in vivo angiogenesis assays, single-cell and spatial transcriptomics |
Research (Washington, D.C.) |
Medium |
38939041
|
| 2012 |
In Xenopus, morpholino-mediated knockdown of golph2/GOLM1 causes edema, enhanced Nephrin expression in the glomus, reduced expression of pronephric tubule/duct markers (atp1b1, ClC-K, NKCC2, NBC1), and expanded WT1 expression, demonstrating that GOLPH2 is required for normal pronephros development by modulating WT1-dependent differentiation of the pronephric field. |
Morpholino knockdown in Xenopus embryos, in situ hybridization for pronephric marker genes, immunostaining for WT1 |
PloS one |
Medium |
22719994
|
| 2022 |
GOLM1 depletion in Huh-7 HCC cells causes aberrant accumulation of ceramides, hexosylceramides, dihexosylceramides, sphinganine, sphingosine, ceramide phosphate, and cholesteryl esters, with reduction in phosphatidylethanolamines, demonstrating that GOLM1 is required for normal cellular sphingolipid homeostasis. GOLM1 depletion also disrupts Golgi structure and reduces mitochondrial oxygen consumption, and impairs cell proliferation. |
siRNA-mediated GOLM1 knockdown, mass spectrometric lipidomics, Seahorse extracellular flux analysis, electron microscopy, immunofluorescence for Golgi structure, cell cycle analysis |
Journal of lipid research |
Medium |
35948172
|
| 2018 |
GP73 promotes epithelial-mesenchymal transition (EMT) and invasion in HCC partly by activating the TGF-β1/Smad2 signaling pathway; GP73 enhances p-Smad2 and p-Smad3 levels by mediating TGF-β1. Blocking the TGF-β1/Smad pathway with SB431542 partially reverses GP73-driven EMT, but GP73 retains some pro-EMT activity through additional pathways. |
GP73 overexpression/knockdown in HCC cell lines, Western blot for p-Smad2/3, TGF-β1/Smad pathway inhibitor (SB431542), in vitro invasion assay, in vivo metastasis model |
Carcinogenesis |
Medium |
29365054
|