{"gene":"TWSG1","run_date":"2026-04-28T21:43:00","timeline":{"discoveries":[{"year":2009,"finding":"TWSG1 (twisted gastrulation protein) suppresses hepcidin expression in human hepatocytes by inhibiting BMP2/BMP4 signaling; in murine hepatocytes it suppresses hepcidin even in the absence of exogenous BMP, identifying it as an erythroid-derived regulator of iron homeostasis","method":"Hepcidin suppression assays (quantitative PCR), dosed recombinant TWSG1 protein treatment of primary hepatocyte cultures, transcriptome analysis of erythropoiesis stages","journal":"Blood","confidence":"High","confidence_rationale":"Tier 2 — multiple orthogonal methods (functional suppression assays with dose-response, pathway placement via BMP inhibition, in vivo thalassemic mouse model), moderate evidence from single lab","pmids":["19414861"],"is_preprint":false},{"year":2005,"finding":"Drosophila Tsg (ortholog of TWSG1) forms a ternary complex with Sog/chordin and BMP ligands (Dpp/Scw heterodimer), facilitating long-range transport of the Dpp/Scw heterodimer to dorsal-most cells; Tsg and Sog are essential for this transport, and the Dpp/Scw heterodimer signals synergistically through two type I BMP receptors (Tkv and Sax)","method":"Genetic epistasis, biochemical co-immunoprecipitation, cell-based signaling assays, mathematical modeling","journal":"Cell","confidence":"High","confidence_rationale":"Tier 1-2 — biochemical and genetic evidence combined, highly cited foundational paper","pmids":["15797386"],"is_preprint":false},{"year":2003,"finding":"Drosophila Tsg sensitizes the BMP patterning mechanism to low levels of Dpp by forming complexes with Sog and Dpp; Tsg promotes Sog cleavage by Tld in a Dpp concentration-dependent manner, creating a positive-negative reinforcement loop that sharpens the Dpp signaling boundary","method":"Cell-based signaling assays, genetic analysis, biochemical interaction assays","journal":"Development","confidence":"High","confidence_rationale":"Tier 2 — multiple biochemical and genetic methods, replicated in context of prior Drosophila work","pmids":["12925593"],"is_preprint":false},{"year":2005,"finding":"Loss of Bmp7 combined with reduction or loss of Tsg (mouse ortholog of TWSG1) causes sirenomelia due to defective ventroposterior mesoderm formation; Bmp7 binds directly to Tsg, and co-injection of Tsg and Bmp7 morpholinos in Xenopus synergistically inhibits ventral mesoderm formation, demonstrating that TWSG1/Tsg modulates BMP7 signaling in dorsoventral patterning of posterior mesoderm","method":"Mouse genetic compound mutant analysis, Xenopus morpholino knockdown, molecular marker studies, direct binding assay","journal":"Development","confidence":"High","confidence_rationale":"Tier 1-2 — genetic epistasis in two model organisms plus direct binding evidence","pmids":["15843411"],"is_preprint":false},{"year":2013,"finding":"TWSG1/Tsg enhances endothelial cell sprouting, migration, and proliferation in a concentration-dependent manner via Akt, Erk, and Smad signaling; paradoxically, silencing of Tsg also increases these activities; Tsg and BMPER interact antagonistically/synergistically to balance BMP pathway activity required for normal zebrafish vascular development","method":"Matrigel sprouting assay, siRNA knockdown, in vivo zebrafish vascular development, signaling pathway analysis (western blot for Akt/Erk/Smad), mouse Matrigel plug assay","journal":"Journal of cell science","confidence":"Medium","confidence_rationale":"Tier 2 — multiple in vitro and in vivo methods but concentration-dependent biphasic effect adds interpretive complexity","pmids":["23641068"],"is_preprint":false}],"current_model":"TWSG1 (twisted gastrulation protein 1) is a secreted BMP-binding modulator that suppresses hepcidin expression in hepatocytes by antagonizing BMP2/BMP4 signaling, acts during erythropoiesis to regulate iron homeostasis (potentially dysregulating it in thalassemia), and in model organisms (Drosophila, mouse, Xenopus) forms extracellular complexes with chordin/Sog and BMP ligands to control BMP gradient formation, dorsoventral patterning, and vascular development."},"narrative":{"teleology":[{"year":2003,"claim":"Establishing that Tsg/TWSG1 is not simply an inhibitor or activator of BMP signaling but instead sensitizes the system to low BMP levels by forming ternary complexes with Sog and Dpp, and by promoting concentration-dependent Sog cleavage by Tld — thereby sharpening signaling boundaries.","evidence":"Cell-based signaling assays, genetic analysis, and biochemical interaction assays in Drosophila","pmids":["12925593"],"confidence":"High","gaps":["Structural basis of Tsg-Sog-BMP ternary complex formation not resolved","Whether the positive-negative reinforcement loop operates identically in vertebrate systems was untested"]},{"year":2005,"claim":"Two studies established that the Tsg/TWSG1 ternary complex has dual biological roles: facilitating long-range BMP heterodimer transport to peak-signaling regions (Drosophila) and cooperating with BMP7 to pattern ventroposterior mesoderm (mouse/Xenopus), the latter demonstrated by sirenomelia in compound mutants.","evidence":"Co-immunoprecipitation, genetic epistasis, and mathematical modeling in Drosophila; compound mutant analysis in mouse and morpholino knockdown in Xenopus with direct binding assays","pmids":["15797386","15843411"],"confidence":"High","gaps":["Whether TWSG1 transports BMP heterodimers in vertebrate embryos as it does in Drosophila was not directly tested","Identity of the relevant BMP heterodimer partners for TWSG1 in mammalian mesoderm patterning was incomplete"]},{"year":2009,"claim":"TWSG1 was identified as an erythroid-derived BMP antagonist that suppresses hepcidin in hepatocytes, connecting its BMP-modulatory activity to systemic iron homeostasis and potentially to iron overload in thalassemia.","evidence":"Dose-response hepcidin suppression assays in primary human and murine hepatocytes, transcriptome profiling of erythropoiesis stages, thalassemic mouse model analysis","pmids":["19414861"],"confidence":"High","gaps":["Whether TWSG1 acts on hepcidin through BMP2/4 receptor complex inhibition at the receptor level or through extracellular ligand sequestration was not mechanistically resolved","Contribution of TWSG1 relative to other erythroid hepcidin suppressors (e.g., ERFE) in vivo not established"]},{"year":2013,"claim":"TWSG1 was shown to regulate endothelial sprouting, migration, and proliferation via Akt, Erk, and Smad pathways, with biphasic concentration-dependent effects and antagonistic/synergistic interplay with BMPER during vascular development.","evidence":"Matrigel sprouting assays, siRNA knockdown, zebrafish vascular development, western blot signaling analysis, mouse Matrigel plug assay","pmids":["23641068"],"confidence":"Medium","gaps":["Biphasic dose-response complicates interpretation of whether TWSG1 is pro- or anti-angiogenic in physiological contexts","The molecular basis for TWSG1-BMPER antagonistic versus synergistic interplay is unresolved","Whether vascular phenotypes are BMP-receptor-dependent or involve alternative signaling pathways was not determined"]},{"year":null,"claim":"The structural basis of TWSG1 ternary complex formation with chordin and BMP ligands, the mechanism by which it discriminates between BMP family members (BMP2/4 vs BMP7), and its relative physiological contribution to hepcidin regulation versus other erythroid factors remain open questions.","evidence":"","pmids":[],"confidence":"Medium","gaps":["No high-resolution structure of a TWSG1-chordin-BMP complex exists","Selectivity determinants for different BMP ligand binding are unknown","In vivo contribution of TWSG1 to iron homeostasis versus other erythroid BMP antagonists has not been dissected genetically in mammals"]}],"mechanism_profile":{"molecular_activity":[{"term_id":"GO:0098772","term_label":"molecular function regulator activity","supporting_discovery_ids":[0,1,2,4]}],"localization":[{"term_id":"GO:0005576","term_label":"extracellular region","supporting_discovery_ids":[0,1,2,3]}],"pathway":[{"term_id":"R-HSA-162582","term_label":"Signal Transduction","supporting_discovery_ids":[0,1,2,3,4]},{"term_id":"R-HSA-1266738","term_label":"Developmental Biology","supporting_discovery_ids":[1,2,3]}],"complexes":[],"partners":["BMP7","BMP2","BMP4","CHRD","BMPER"],"other_free_text":[]},"mechanistic_narrative":"TWSG1 encodes a secreted BMP-binding glycoprotein that modulates BMP signaling gradients through formation of extracellular complexes with chordin/Sog and BMP ligands (Dpp, BMP7, BMP2/4), functioning as both a facilitator of long-range BMP ligand transport and a sensitizer of BMP gradient sharpening via concentration-dependent promotion of chordin/Sog cleavage by tolloid-family metalloproteinases [PMID:15797386, PMID:12925593]. In vertebrates, TWSG1 cooperates with BMP7 to pattern ventroposterior mesoderm, as demonstrated by sirenomelia in Bmp7/Tsg compound-mutant mice and synergistic ventral mesoderm loss in Xenopus morpholino co-injection experiments [PMID:15843411]. TWSG1 also functions as an erythroid-derived suppressor of hepcidin expression in hepatocytes by antagonizing BMP2/BMP4 signaling, linking it to systemic iron homeostasis regulation [PMID:19414861]."},"prefetch_data":{"uniprot":{"accession":"Q9GZX9","full_name":"Twisted gastrulation protein homolog 1","aliases":[],"length_aa":223,"mass_kda":25.0,"function":"May be involved in dorsoventral axis formation. Seems to antagonize BMP signaling by forming ternary complexes with CHRD and BMPs, thereby preventing BMPs from binding to their receptors. In addition to the anti-BMP function, also has pro-BMP activity, partly mediated by cleavage and degradation of CHRD, which releases BMPs from ternary complexes. May be an important modulator of BMP-regulated cartilage development and chondrocyte differentiation. May play a role in thymocyte development (By similarity)","subcellular_location":"Secreted","url":"https://www.uniprot.org/uniprotkb/Q9GZX9/entry"},"depmap":{"release":"DepMap","has_data":true,"is_common_essential":false,"resolved_as":"","url":"https://depmap.org/portal/gene/TWSG1","classification":"Not Classified","n_dependent_lines":0,"n_total_lines":1208,"dependency_fraction":0.0},"opencell":{"profiled":false,"resolved_as":"","ensg_id":"","cell_line_id":"","localizations":[],"interactors":[],"url":"https://opencell.sf.czbiohub.org/search/TWSG1","total_profiled":1310},"omim":[{"mim_id":"613127","title":"CHORDIN-LIKE 2; CHRDL2","url":"https://www.omim.org/entry/613127"},{"mim_id":"605049","title":"TWISTED GASTRULATION BMP MODULATOR 1; TWSG1","url":"https://www.omim.org/entry/605049"},{"mim_id":"604685","title":"HOMEOBOX A2; HOXA2","url":"https://www.omim.org/entry/604685"}],"hpa":{"profiled":true,"resolved_as":"","reliability":"Supported","locations":[{"location":"Centrosome","reliability":"Supported"},{"location":"Cytosol","reliability":"Supported"}],"tissue_specificity":"Low tissue specificity","tissue_distribution":"Detected in all","driving_tissues":[],"url":"https://www.proteinatlas.org/search/TWSG1"},"hgnc":{"alias_symbol":["TSG"],"prev_symbol":[]},"alphafold":{"accession":"Q9GZX9","domains":[{"cath_id":"-","chopping":"27-84","consensus_level":"medium","plddt":87.0622,"start":27,"end":84},{"cath_id":"-","chopping":"86-124_164-223","consensus_level":"medium","plddt":92.4468,"start":86,"end":223}],"viewer_url":"https://alphafold.ebi.ac.uk/entry/Q9GZX9","model_url":"https://alphafold.ebi.ac.uk/files/AF-Q9GZX9-F1-model_v6.cif","pae_url":"https://alphafold.ebi.ac.uk/files/AF-Q9GZX9-F1-predicted_aligned_error_v6.png","plddt_mean":80.38},"mouse_models":{"mgi_url":"https://www.informatics.jax.org/marker/summary?nomen=TWSG1","jax_strain_url":"https://www.jax.org/strain/search?query=TWSG1"},"sequence":{"accession":"Q9GZX9","fasta_url":"https://rest.uniprot.org/uniprotkb/Q9GZX9.fasta","uniprot_url":"https://www.uniprot.org/uniprotkb/Q9GZX9/entry","alphafold_viewer_url":"https://alphafold.ebi.ac.uk/entry/Q9GZX9"}},"corpus_meta":[{"pmid":"19570514","id":"PMC_19570514","title":"Intravenous hMSCs improve myocardial infarction in mice because cells embolized in lung are activated to secrete the anti-inflammatory protein TSG-6.","date":"2009","source":"Cell stem cell","url":"https://pubmed.ncbi.nlm.nih.gov/19570514","citation_count":1493,"is_preprint":false},{"pmid":"21551236","id":"PMC_21551236","title":"Anti-inflammatory protein TSG-6 secreted by activated MSCs attenuates zymosan-induced mouse peritonitis by decreasing TLR2/NF-κB signaling in resident macrophages.","date":"2011","source":"Blood","url":"https://pubmed.ncbi.nlm.nih.gov/21551236","citation_count":538,"is_preprint":false},{"pmid":"12692188","id":"PMC_12692188","title":"TSG-6: a multifunctional protein associated with inflammation.","date":"2003","source":"Journal of cell science","url":"https://pubmed.ncbi.nlm.nih.gov/12692188","citation_count":313,"is_preprint":false},{"pmid":"19414861","id":"PMC_19414861","title":"Identification of TWSG1 as a second novel erythroid regulator of hepcidin expression in murine and human cells.","date":"2009","source":"Blood","url":"https://pubmed.ncbi.nlm.nih.gov/19414861","citation_count":275,"is_preprint":false},{"pmid":"1730767","id":"PMC_1730767","title":"A novel secretory tumor necrosis factor-inducible protein (TSG-6) is a member of the family of hyaluronate binding proteins, closely related to the adhesion receptor CD44.","date":"1992","source":"The Journal of cell biology","url":"https://pubmed.ncbi.nlm.nih.gov/1730767","citation_count":273,"is_preprint":false},{"pmid":"15797386","id":"PMC_15797386","title":"Facilitated transport of a Dpp/Scw heterodimer by Sog/Tsg leads to robust patterning of the Drosophila blastoderm embryo.","date":"2005","source":"Cell","url":"https://pubmed.ncbi.nlm.nih.gov/15797386","citation_count":250,"is_preprint":false},{"pmid":"29362135","id":"PMC_29362135","title":"TSG-6: A multifunctional protein with anti-inflammatory and tissue-protective properties.","date":"2018","source":"Matrix biology : journal of the International Society for Matrix Biology","url":"https://pubmed.ncbi.nlm.nih.gov/29362135","citation_count":249,"is_preprint":false},{"pmid":"7679696","id":"PMC_7679696","title":"TSG-14, a tumor necrosis factor- and IL-1-inducible protein, is a novel member of the pentaxin family of acute phase proteins.","date":"1993","source":"Journal of immunology (Baltimore, Md. : 1950)","url":"https://pubmed.ncbi.nlm.nih.gov/7679696","citation_count":220,"is_preprint":false},{"pmid":"23921952","id":"PMC_23921952","title":"TSG-6 released from intradermally injected mesenchymal stem cells accelerates wound healing and reduces tissue fibrosis in murine full-thickness skin wounds.","date":"2013","source":"The Journal of investigative dermatology","url":"https://pubmed.ncbi.nlm.nih.gov/23921952","citation_count":195,"is_preprint":false},{"pmid":"20837529","id":"PMC_20837529","title":"Anti-inflammatory protein TSG-6 reduces inflammatory damage to the cornea following chemical and mechanical injury.","date":"2010","source":"Proceedings of the National Academy of Sciences of the United States of America","url":"https://pubmed.ncbi.nlm.nih.gov/20837529","citation_count":190,"is_preprint":false},{"pmid":"8568267","id":"PMC_8568267","title":"TNF/IL-1-inducible protein TSG-6 potentiates plasmin inhibition by inter-alpha-inhibitor and exerts a strong anti-inflammatory effect in vivo.","date":"1996","source":"Journal of immunology (Baltimore, Md. : 1950)","url":"https://pubmed.ncbi.nlm.nih.gov/8568267","citation_count":182,"is_preprint":false},{"pmid":"16709183","id":"PMC_16709183","title":"TSG-6: a pluripotent inflammatory mediator?","date":"2006","source":"Biochemical Society transactions","url":"https://pubmed.ncbi.nlm.nih.gov/16709183","citation_count":182,"is_preprint":false},{"pmid":"29238069","id":"PMC_29238069","title":"Kynurenic acid, an IDO metabolite, controls TSG-6-mediated immunosuppression of human mesenchymal stem cells.","date":"2017","source":"Cell death and differentiation","url":"https://pubmed.ncbi.nlm.nih.gov/29238069","citation_count":165,"is_preprint":false},{"pmid":"9244409","id":"PMC_9244409","title":"TSG-6: an IL-1/TNF-inducible protein with anti-inflammatory activity.","date":"1997","source":"Cytokine & growth factor reviews","url":"https://pubmed.ncbi.nlm.nih.gov/9244409","citation_count":151,"is_preprint":false},{"pmid":"15060082","id":"PMC_15060082","title":"TSG-6 modulates the interaction between hyaluronan and cell surface CD44.","date":"2004","source":"The Journal of biological chemistry","url":"https://pubmed.ncbi.nlm.nih.gov/15060082","citation_count":151,"is_preprint":false},{"pmid":"15840581","id":"PMC_15840581","title":"Characterization of complexes formed between TSG-6 and inter-alpha-inhibitor that act as intermediates in the covalent transfer of heavy chains onto hyaluronan.","date":"2005","source":"The Journal of biological chemistry","url":"https://pubmed.ncbi.nlm.nih.gov/15840581","citation_count":151,"is_preprint":false},{"pmid":"29941022","id":"PMC_29941022","title":"Early gestational mesenchymal stem cell secretome attenuates experimental bronchopulmonary dysplasia in part via exosome-associated factor TSG-6.","date":"2018","source":"Stem cell research & therapy","url":"https://pubmed.ncbi.nlm.nih.gov/29941022","citation_count":150,"is_preprint":false},{"pmid":"32393298","id":"PMC_32393298","title":"Anti-inflammatory protein TSG-6 secreted by bone marrow mesenchymal stem cells attenuates neuropathic pain by inhibiting the TLR2/MyD88/NF-κB signaling pathway in spinal microglia.","date":"2020","source":"Journal of neuroinflammation","url":"https://pubmed.ncbi.nlm.nih.gov/32393298","citation_count":135,"is_preprint":false},{"pmid":"8245487","id":"PMC_8245487","title":"TSG-6: a TNF-, IL-1-, and LPS-inducible secreted glycoprotein associated with arthritis.","date":"1993","source":"Journal of immunology (Baltimore, Md. : 1950)","url":"https://pubmed.ncbi.nlm.nih.gov/8245487","citation_count":135,"is_preprint":false},{"pmid":"34051868","id":"PMC_34051868","title":"A novel therapeutic approach for inflammatory bowel disease by exosomes derived from human umbilical cord mesenchymal stem cells to repair intestinal barrier via TSG-6.","date":"2021","source":"Stem cell research & therapy","url":"https://pubmed.ncbi.nlm.nih.gov/34051868","citation_count":132,"is_preprint":false},{"pmid":"23349496","id":"PMC_23349496","title":"TSG-6 produced by hMSCs delays the onset of autoimmune diabetes by suppressing Th1 development and enhancing tolerogenicity.","date":"2013","source":"Diabetes","url":"https://pubmed.ncbi.nlm.nih.gov/23349496","citation_count":125,"is_preprint":false},{"pmid":"21596748","id":"PMC_21596748","title":"The inflammation-associated protein TSG-6 cross-links hyaluronan via hyaluronan-induced TSG-6 oligomers.","date":"2011","source":"The Journal of biological chemistry","url":"https://pubmed.ncbi.nlm.nih.gov/21596748","citation_count":116,"is_preprint":false},{"pmid":"11696432","id":"PMC_11696432","title":"Anti-inflammatory and chondroprotective effect of TSG-6 (tumor necrosis factor-alpha-stimulated gene-6) in murine models of experimental arthritis.","date":"2001","source":"The American journal of pathology","url":"https://pubmed.ncbi.nlm.nih.gov/11696432","citation_count":115,"is_preprint":false},{"pmid":"12401803","id":"PMC_12401803","title":"The link module from human TSG-6 inhibits neutrophil migration in a hyaluronan- and inter-alpha -inhibitor-independent manner.","date":"2002","source":"The Journal of biological chemistry","url":"https://pubmed.ncbi.nlm.nih.gov/12401803","citation_count":106,"is_preprint":false},{"pmid":"7516184","id":"PMC_7516184","title":"TSG-6, an arthritis-associated hyaluronan binding protein, forms a stable complex with the serum protein inter-alpha-inhibitor.","date":"1994","source":"Biochemistry","url":"https://pubmed.ncbi.nlm.nih.gov/7516184","citation_count":102,"is_preprint":false},{"pmid":"11404378","id":"PMC_11404378","title":"TSG-14 transgenic mice have improved survival to endotoxemia and to CLP-induced sepsis.","date":"2001","source":"Journal of leukocyte biology","url":"https://pubmed.ncbi.nlm.nih.gov/11404378","citation_count":100,"is_preprint":false},{"pmid":"25088370","id":"PMC_25088370","title":"Mesenchymal stem cells inhibit lipopolysaccharide-induced inflammatory responses of BV2 microglial cells through TSG-6.","date":"2014","source":"Journal of neuroinflammation","url":"https://pubmed.ncbi.nlm.nih.gov/25088370","citation_count":99,"is_preprint":false},{"pmid":"12925593","id":"PMC_12925593","title":"Physical properties of Tld, Sog, Tsg and Dpp protein interactions are predicted to help create a sharp boundary in Bmp signals during dorsoventral patterning of the Drosophila embryo.","date":"2003","source":"Development (Cambridge, England)","url":"https://pubmed.ncbi.nlm.nih.gov/12925593","citation_count":98,"is_preprint":false},{"pmid":"25890011","id":"PMC_25890011","title":"The inhibitory effect of mesenchymal stem cell on blood-brain barrier disruption following intracerebral hemorrhage in rats: contribution of TSG-6.","date":"2015","source":"Journal of neuroinflammation","url":"https://pubmed.ncbi.nlm.nih.gov/25890011","citation_count":96,"is_preprint":false},{"pmid":"28810264","id":"PMC_28810264","title":"Mesenchymal Stem Cells Promote Diabetic Corneal Epithelial Wound Healing Through TSG-6-Dependent Stem Cell Activation and Macrophage Switch.","date":"2017","source":"Investigative ophthalmology & visual science","url":"https://pubmed.ncbi.nlm.nih.gov/28810264","citation_count":95,"is_preprint":false},{"pmid":"30126439","id":"PMC_30126439","title":"TSG-6 attenuates inflammation-induced brain injury via modulation of microglial polarization in SAH rats through the SOCS3/STAT3 pathway.","date":"2018","source":"Journal of neuroinflammation","url":"https://pubmed.ncbi.nlm.nih.gov/30126439","citation_count":94,"is_preprint":false},{"pmid":"22912904","id":"PMC_22912904","title":"Mesenchymal stem cells attenuate peritoneal injury through secretion of TSG-6.","date":"2012","source":"PloS one","url":"https://pubmed.ncbi.nlm.nih.gov/22912904","citation_count":90,"is_preprint":false},{"pmid":"27044744","id":"PMC_27044744","title":"The Anti-inflammatory Protein TSG-6 Regulates Chemokine Function by Inhibiting Chemokine/Glycosaminoglycan Interactions.","date":"2016","source":"The Journal of biological chemistry","url":"https://pubmed.ncbi.nlm.nih.gov/27044744","citation_count":88,"is_preprint":false},{"pmid":"23851308","id":"PMC_23851308","title":"Administration of TSG-6 improves memory after traumatic brain injury in mice.","date":"2013","source":"Neurobiology of disease","url":"https://pubmed.ncbi.nlm.nih.gov/23851308","citation_count":85,"is_preprint":false},{"pmid":"11420253","id":"PMC_11420253","title":"TSG-6 is concentrated in the extracellular matrix of mouse cumulus oocyte complexes through hyaluronan and inter-alpha-inhibitor binding.","date":"2001","source":"Biology of reproduction","url":"https://pubmed.ncbi.nlm.nih.gov/11420253","citation_count":84,"is_preprint":false},{"pmid":"19389798","id":"PMC_19389798","title":"Coregulation in human leukocytes of the long pentraxin PTX3 and TSG-6.","date":"2009","source":"Journal of leukocyte biology","url":"https://pubmed.ncbi.nlm.nih.gov/19389798","citation_count":79,"is_preprint":false},{"pmid":"10903951","id":"PMC_10903951","title":"Localization and characterization of the hyaluronan-binding site on the link module from human TSG-6.","date":"2000","source":"Structure (London, England : 1993)","url":"https://pubmed.ncbi.nlm.nih.gov/10903951","citation_count":78,"is_preprint":false},{"pmid":"29301108","id":"PMC_29301108","title":"Mesenchymal Stromal Cells Inhibit Inflammatory Lymphangiogenesis in the Cornea by Suppressing Macrophage in a TSG-6-Dependent Manner.","date":"2017","source":"Molecular therapy : the journal of the American Society of Gene Therapy","url":"https://pubmed.ncbi.nlm.nih.gov/29301108","citation_count":78,"is_preprint":false},{"pmid":"15457471","id":"PMC_15457471","title":"Enhanced neutrophil extravasation and rapid progression of proteoglycan-induced arthritis in TSG-6-knockout mice.","date":"2004","source":"Arthritis and rheumatism","url":"https://pubmed.ncbi.nlm.nih.gov/15457471","citation_count":76,"is_preprint":false},{"pmid":"12972412","id":"PMC_12972412","title":"The link module from ovulation- and inflammation-associated protein TSG-6 changes conformation on hyaluronan binding.","date":"2003","source":"The Journal of biological chemistry","url":"https://pubmed.ncbi.nlm.nih.gov/12972412","citation_count":73,"is_preprint":false},{"pmid":"32800897","id":"PMC_32800897","title":"Exosomes derived from TSG-6 modified mesenchymal stromal cells attenuate scar formation during wound healing.","date":"2020","source":"Biochimie","url":"https://pubmed.ncbi.nlm.nih.gov/32800897","citation_count":69,"is_preprint":false},{"pmid":"35690131","id":"PMC_35690131","title":"Exosomes from LPS-preconditioned bone marrow MSCs accelerated peripheral nerve regeneration via M2 macrophage polarization: Involvement of TSG-6/NF-κB/NLRP3 signaling pathway.","date":"2022","source":"Experimental neurology","url":"https://pubmed.ncbi.nlm.nih.gov/35690131","citation_count":69,"is_preprint":false},{"pmid":"9237673","id":"PMC_9237673","title":"Overlapping sites on the Link module of human TSG-6 mediate binding to hyaluronan and chrondroitin-4-sulphate.","date":"1997","source":"FEBS letters","url":"https://pubmed.ncbi.nlm.nih.gov/9237673","citation_count":68,"is_preprint":false},{"pmid":"7523502","id":"PMC_7523502","title":"Relationship of TSG-14 protein to the pentraxin family of major acute phase proteins.","date":"1994","source":"Journal of immunology (Baltimore, Md. : 1950)","url":"https://pubmed.ncbi.nlm.nih.gov/7523502","citation_count":66,"is_preprint":false},{"pmid":"15843411","id":"PMC_15843411","title":"Sirenomelia in Bmp7 and Tsg compound mutant mice: requirement for Bmp signaling in the development of ventral posterior mesoderm.","date":"2005","source":"Development (Cambridge, England)","url":"https://pubmed.ncbi.nlm.nih.gov/15843411","citation_count":65,"is_preprint":false},{"pmid":"12011075","id":"PMC_12011075","title":"Hyaluronan binding properties of a CD44 chimera containing the link module of TSG-6.","date":"2002","source":"The Journal of biological chemistry","url":"https://pubmed.ncbi.nlm.nih.gov/12011075","citation_count":65,"is_preprint":false},{"pmid":"12355494","id":"PMC_12355494","title":"Reduced susceptibility to collagen-induced arthritis in DBA/1J mice expressing the TSG-6 transgene.","date":"2002","source":"Arthritis and rheumatism","url":"https://pubmed.ncbi.nlm.nih.gov/12355494","citation_count":64,"is_preprint":false},{"pmid":"24005673","id":"PMC_24005673","title":"Inter-α-inhibitor impairs TSG-6-induced hyaluronan cross-linking.","date":"2013","source":"The Journal of biological chemistry","url":"https://pubmed.ncbi.nlm.nih.gov/24005673","citation_count":63,"is_preprint":false},{"pmid":"31903104","id":"PMC_31903104","title":"Liver-targeted delivery of TSG-6 by calcium phosphate nanoparticles for the management of liver fibrosis.","date":"2020","source":"Theranostics","url":"https://pubmed.ncbi.nlm.nih.gov/31903104","citation_count":62,"is_preprint":false},{"pmid":"11145024","id":"PMC_11145024","title":"Amelioration of collagen-induced arthritis in DBA/1J mice by recombinant TSG-6, a tumor necrosis factor/interleukin-1-inducible protein.","date":"2000","source":"Arthritis and rheumatism","url":"https://pubmed.ncbi.nlm.nih.gov/11145024","citation_count":62,"is_preprint":false},{"pmid":"24979372","id":"PMC_24979372","title":"Therapeutic effect of TSG-6 engineered iPSC-derived MSCs on experimental periodontitis in rats: a pilot study.","date":"2014","source":"PloS one","url":"https://pubmed.ncbi.nlm.nih.gov/24979372","citation_count":61,"is_preprint":false},{"pmid":"20642475","id":"PMC_20642475","title":"Characterization of hyaluronan and TSG-6 in skin scarring: differential distribution in keloid scars, normal scars and unscarred skin.","date":"2011","source":"Journal of the European Academy of Dermatology and Venereology : JEADV","url":"https://pubmed.ncbi.nlm.nih.gov/20642475","citation_count":61,"is_preprint":false},{"pmid":"27435674","id":"PMC_27435674","title":"Tumor Necrosis Factor-stimulated Gene-6 (TSG-6) Is Constitutively Expressed in Adult Central Nervous System (CNS) and Associated with Astrocyte-mediated Glial Scar Formation following Spinal Cord Injury.","date":"2016","source":"The Journal of biological chemistry","url":"https://pubmed.ncbi.nlm.nih.gov/27435674","citation_count":59,"is_preprint":false},{"pmid":"9654129","id":"PMC_9654129","title":"TSG-6 interacts with hyaluronan and aggrecan in a pH-dependent manner via a common functional element: implications for its regulation in inflamed cartilage.","date":"1998","source":"FEBS letters","url":"https://pubmed.ncbi.nlm.nih.gov/9654129","citation_count":59,"is_preprint":false},{"pmid":"23118230","id":"PMC_23118230","title":"TSG-6 protein is crucial for the development of pulmonary hyaluronan deposition, eosinophilia, and airway hyperresponsiveness in a murine model of asthma.","date":"2012","source":"The Journal of biological chemistry","url":"https://pubmed.ncbi.nlm.nih.gov/23118230","citation_count":57,"is_preprint":false},{"pmid":"10733100","id":"PMC_10733100","title":"Differential regulation of TSG-14 expression in murine fibroblasts and peritoneal macrophages.","date":"2000","source":"Journal of leukocyte biology","url":"https://pubmed.ncbi.nlm.nih.gov/10733100","citation_count":56,"is_preprint":false},{"pmid":"25014173","id":"PMC_25014173","title":"MSCs inhibit bone marrow-derived DC maturation and function through the release of TSG-6.","date":"2014","source":"Biochemical and biophysical research communications","url":"https://pubmed.ncbi.nlm.nih.gov/25014173","citation_count":56,"is_preprint":false},{"pmid":"24242012","id":"PMC_24242012","title":"Phase-directed therapy: TSG-6 targeted to early inflammation improves bleomycin-injured lungs.","date":"2013","source":"American journal of physiology. Lung cellular and molecular physiology","url":"https://pubmed.ncbi.nlm.nih.gov/24242012","citation_count":53,"is_preprint":false},{"pmid":"12622693","id":"PMC_12622693","title":"Role of tumour necrosis factor stimulated gene 6 (TSG-6) in the coupling of inter-alpha-trypsin inhibitor to hyaluronan in human follicular fluid.","date":"2003","source":"Reproduction (Cambridge, England)","url":"https://pubmed.ncbi.nlm.nih.gov/12622693","citation_count":53,"is_preprint":false},{"pmid":"7586156","id":"PMC_7586156","title":"K-ras mutations in lung tumors from A/J and A/J x TSG-p53 F1 mice treated with 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone and phenethyl isothiocyanate.","date":"1995","source":"Carcinogenesis","url":"https://pubmed.ncbi.nlm.nih.gov/7586156","citation_count":50,"is_preprint":false},{"pmid":"23885148","id":"PMC_23885148","title":"Underexpression of LATS1 TSG in colorectal cancer is associated with promoter hypermethylation.","date":"2013","source":"World journal of gastroenterology","url":"https://pubmed.ncbi.nlm.nih.gov/23885148","citation_count":49,"is_preprint":false},{"pmid":"26468290","id":"PMC_26468290","title":"Metal Ion-dependent Heavy Chain Transfer Activity of TSG-6 Mediates Assembly of the Cumulus-Oocyte Matrix.","date":"2015","source":"The Journal of biological chemistry","url":"https://pubmed.ncbi.nlm.nih.gov/26468290","citation_count":49,"is_preprint":false},{"pmid":"8812829","id":"PMC_8812829","title":"Overexpression, purification, and refolding of link module from human TSG-6 in Escherichia coli: effect of temperature, media, and mutagenesis on lysine misincorporation at arginine AGA codons.","date":"1996","source":"Protein expression and purification","url":"https://pubmed.ncbi.nlm.nih.gov/8812829","citation_count":49,"is_preprint":false},{"pmid":"18586671","id":"PMC_18586671","title":"TSG-6 regulates bone remodeling through inhibition of osteoblastogenesis and osteoclast activation.","date":"2008","source":"The Journal of biological chemistry","url":"https://pubmed.ncbi.nlm.nih.gov/18586671","citation_count":47,"is_preprint":false},{"pmid":"15513871","id":"PMC_15513871","title":"Inhibitory effects of TSG-6 Link module on leukocyte-endothelial cell interactions in vitro and in vivo.","date":"2004","source":"Microcirculation (New York, N.Y. : 1994)","url":"https://pubmed.ncbi.nlm.nih.gov/15513871","citation_count":46,"is_preprint":false},{"pmid":"31472111","id":"PMC_31472111","title":"Mesenchymal stem cells enhance microglia M2 polarization and attenuate neuroinflammation through TSG-6.","date":"2019","source":"Brain research","url":"https://pubmed.ncbi.nlm.nih.gov/31472111","citation_count":45,"is_preprint":false},{"pmid":"29483622","id":"PMC_29483622","title":"TSG-6 secreted by bone marrow mesenchymal stem cells attenuates intervertebral disc degeneration by inhibiting the TLR2/NF-κB signaling pathway.","date":"2018","source":"Laboratory investigation; a journal of technical methods and pathology","url":"https://pubmed.ncbi.nlm.nih.gov/29483622","citation_count":45,"is_preprint":false},{"pmid":"21162099","id":"PMC_21162099","title":"TSG-6 inhibits osteoclast activity via an autocrine mechanism and is functionally synergistic with osteoprotegerin.","date":"2011","source":"Arthritis and rheumatism","url":"https://pubmed.ncbi.nlm.nih.gov/21162099","citation_count":44,"is_preprint":false},{"pmid":"23129777","id":"PMC_23129777","title":"Tumor necrosis factor-stimulated gene-6 (TSG-6) amplifies hyaluronan synthesis by airway smooth muscle cells.","date":"2012","source":"The Journal of biological chemistry","url":"https://pubmed.ncbi.nlm.nih.gov/23129777","citation_count":44,"is_preprint":false},{"pmid":"31606534","id":"PMC_31606534","title":"Inflammation inhibition and gut microbiota regulation by TSG to combat atherosclerosis in ApoE-/- mice.","date":"2019","source":"Journal of ethnopharmacology","url":"https://pubmed.ncbi.nlm.nih.gov/31606534","citation_count":43,"is_preprint":false},{"pmid":"24403066","id":"PMC_24403066","title":"A refined model for the TSG-6 link module in complex with hyaluronan: use of defined oligosaccharides to probe structure and function.","date":"2014","source":"The Journal of biological chemistry","url":"https://pubmed.ncbi.nlm.nih.gov/24403066","citation_count":43,"is_preprint":false},{"pmid":"8630102","id":"PMC_8630102","title":"TSG-6 expression in human articular chondrocytes. Possible implications in joint inflammation and cartilage degradation.","date":"1996","source":"Arthritis and rheumatism","url":"https://pubmed.ncbi.nlm.nih.gov/8630102","citation_count":42,"is_preprint":false},{"pmid":"30507579","id":"PMC_30507579","title":"Increased Hyaluronan and TSG-6 in Association with Neuropathologic Changes of Alzheimer's Disease.","date":"2019","source":"Journal of Alzheimer's disease : JAD","url":"https://pubmed.ncbi.nlm.nih.gov/30507579","citation_count":41,"is_preprint":false},{"pmid":"27143355","id":"PMC_27143355","title":"Tumor Necrosis Factor-stimulated Gene 6 (TSG-6)-mediated Interactions with the Inter-α-inhibitor Heavy Chain 5 Facilitate Tumor Growth Factor β1 (TGFβ1)-dependent Fibroblast to Myofibroblast Differentiation.","date":"2016","source":"The Journal of biological chemistry","url":"https://pubmed.ncbi.nlm.nih.gov/27143355","citation_count":41,"is_preprint":false},{"pmid":"29129649","id":"PMC_29129649","title":"TSG-6 - a double-edged sword for osteoarthritis (OA).","date":"2017","source":"Osteoarthritis and cartilage","url":"https://pubmed.ncbi.nlm.nih.gov/29129649","citation_count":41,"is_preprint":false},{"pmid":"18042364","id":"PMC_18042364","title":"TSG-6 binds via its CUB_C domain to the cell-binding domain of fibronectin and increases fibronectin matrix assembly.","date":"2007","source":"Matrix biology : journal of the International Society for Matrix Biology","url":"https://pubmed.ncbi.nlm.nih.gov/18042364","citation_count":38,"is_preprint":false},{"pmid":"26474417","id":"PMC_26474417","title":"Naturally Occurring Stilbenoid TSG Reverses Non-Alcoholic Fatty Liver Diseases via Gut-Liver Axis.","date":"2015","source":"PloS one","url":"https://pubmed.ncbi.nlm.nih.gov/26474417","citation_count":38,"is_preprint":false},{"pmid":"36433947","id":"PMC_36433947","title":"Mesenchymal stem/stromal cells primed by inflammatory cytokines alleviate psoriasis-like inflammation via the TSG-6-neutrophil axis.","date":"2022","source":"Cell death & disease","url":"https://pubmed.ncbi.nlm.nih.gov/36433947","citation_count":37,"is_preprint":false},{"pmid":"28987946","id":"PMC_28987946","title":"Tetrahydroxy stilbene glycoside (TSG) antagonizes Aβ-induced hippocampal neuron injury by suppressing mitochondrial dysfunction via Nrf2-dependent HO-1 pathway.","date":"2017","source":"Biomedicine & pharmacotherapy = Biomedecine & pharmacotherapie","url":"https://pubmed.ncbi.nlm.nih.gov/28987946","citation_count":37,"is_preprint":false},{"pmid":"15062856","id":"PMC_15062856","title":"Cartilage link protein interacts with neurocan, which shows hyaluronan binding characteristics different from CD44 and TSG-6.","date":"2004","source":"Matrix biology : journal of the International Society for Matrix Biology","url":"https://pubmed.ncbi.nlm.nih.gov/15062856","citation_count":37,"is_preprint":false},{"pmid":"28963485","id":"PMC_28963485","title":"Human Amniotic Membrane Mesenchymal Stem Cells inhibit Neutrophil Extracellular Traps through TSG-6.","date":"2017","source":"Scientific reports","url":"https://pubmed.ncbi.nlm.nih.gov/28963485","citation_count":37,"is_preprint":false},{"pmid":"15699048","id":"PMC_15699048","title":"TSG-6 protein binding to glycosaminoglycans: formation of stable complexes with hyaluronan and binding to chondroitin sulfates.","date":"2005","source":"The Journal of biological chemistry","url":"https://pubmed.ncbi.nlm.nih.gov/15699048","citation_count":36,"is_preprint":false},{"pmid":"33670243","id":"PMC_33670243","title":"HGF and TSG-6 Released by Mesenchymal Stem Cells Attenuate Colon Radiation-Induced Fibrosis.","date":"2021","source":"International journal of molecular sciences","url":"https://pubmed.ncbi.nlm.nih.gov/33670243","citation_count":35,"is_preprint":false},{"pmid":"16006654","id":"PMC_16006654","title":"The N-terminal module of thrombospondin-1 interacts with the link domain of TSG-6 and enhances its covalent association with the heavy chains of inter-alpha-trypsin inhibitor.","date":"2005","source":"The Journal of biological chemistry","url":"https://pubmed.ncbi.nlm.nih.gov/16006654","citation_count":35,"is_preprint":false},{"pmid":"26807900","id":"PMC_26807900","title":"Comparison of Topical Application of TSG-6, Cyclosporine, and Prednisolone for Treating Dry Eye.","date":"2016","source":"Cornea","url":"https://pubmed.ncbi.nlm.nih.gov/26807900","citation_count":34,"is_preprint":false},{"pmid":"25661977","id":"PMC_25661977","title":"Anti-inflammatory cytokine TSG-6 inhibits hypertrophic scar formation in a rabbit ear model.","date":"2015","source":"European journal of pharmacology","url":"https://pubmed.ncbi.nlm.nih.gov/25661977","citation_count":34,"is_preprint":false},{"pmid":"29564448","id":"PMC_29564448","title":"Intra-articular TSG-6 delivery from heparin-based microparticles reduces cartilage damage in a rat model of osteoarthritis.","date":"2018","source":"Biomaterials science","url":"https://pubmed.ncbi.nlm.nih.gov/29564448","citation_count":34,"is_preprint":false},{"pmid":"24983309","id":"PMC_24983309","title":"Adipose tissue-derived stem cells suppress acute cellular rejection by TSG-6 and CD44 interaction in rat kidney transplantation.","date":"2014","source":"Transplantation","url":"https://pubmed.ncbi.nlm.nih.gov/24983309","citation_count":34,"is_preprint":false},{"pmid":"34112260","id":"PMC_34112260","title":"Placental chorionic plate-derived mesenchymal stem cells ameliorate severe acute pancreatitis by regulating macrophage polarization via secreting TSG-6.","date":"2021","source":"Stem cell research & therapy","url":"https://pubmed.ncbi.nlm.nih.gov/34112260","citation_count":34,"is_preprint":false},{"pmid":"18448433","id":"PMC_18448433","title":"The transfer of heavy chains from bikunin proteins to hyaluronan requires both TSG-6 and HC2.","date":"2008","source":"The Journal of biological chemistry","url":"https://pubmed.ncbi.nlm.nih.gov/18448433","citation_count":33,"is_preprint":false},{"pmid":"22452753","id":"PMC_22452753","title":"Anti-inflammatory recombinant TSG-6 stabilizes the progression of focal retinal degeneration in a murine model.","date":"2012","source":"Journal of neuroinflammation","url":"https://pubmed.ncbi.nlm.nih.gov/22452753","citation_count":32,"is_preprint":false},{"pmid":"23641068","id":"PMC_23641068","title":"Antagonism and synergy between extracellular BMP modulators Tsg and BMPER balance blood vessel formation.","date":"2013","source":"Journal of cell science","url":"https://pubmed.ncbi.nlm.nih.gov/23641068","citation_count":31,"is_preprint":false},{"pmid":"31044513","id":"PMC_31044513","title":"Hyaluronan preconditioning of monocytes/macrophages affects their angiogenic behavior and regulation of TSG-6 expression in a tumor type-specific manner.","date":"2019","source":"The FEBS journal","url":"https://pubmed.ncbi.nlm.nih.gov/31044513","citation_count":31,"is_preprint":false},{"pmid":"33554782","id":"PMC_33554782","title":"Mesenchymal stem cells protect renal tubular cells via TSG-6 regulating macrophage function and phenotype switching.","date":"2021","source":"American journal of physiology. Renal physiology","url":"https://pubmed.ncbi.nlm.nih.gov/33554782","citation_count":30,"is_preprint":false},{"pmid":"35280699","id":"PMC_35280699","title":"TSG-6 promotes Cancer Cell aggressiveness in a CD44-Dependent Manner and Reprograms Normal Fibroblasts to create a Pro-metastatic Microenvironment in Colorectal Cancer.","date":"2022","source":"International journal of biological sciences","url":"https://pubmed.ncbi.nlm.nih.gov/35280699","citation_count":29,"is_preprint":false},{"pmid":"34145502","id":"PMC_34145502","title":"Tumor Necrosis Factor-stimulated Gene-6 (TSG-6) Secreted by BMSCs Regulates Activated Astrocytes by Inhibiting NF-κB Signaling Pathway to Ameliorate Blood Brain Barrier Damage After Intracerebral Hemorrhage.","date":"2021","source":"Neurochemical research","url":"https://pubmed.ncbi.nlm.nih.gov/34145502","citation_count":29,"is_preprint":false},{"pmid":"35820593","id":"PMC_35820593","title":"Matrix stiffness regulates the immunomodulatory effects of mesenchymal stem cells on macrophages via AP1/TSG-6 signaling pathways.","date":"2022","source":"Acta biomaterialia","url":"https://pubmed.ncbi.nlm.nih.gov/35820593","citation_count":28,"is_preprint":false},{"pmid":"23445528","id":"PMC_23445528","title":"TSG: a new algorithm for binary and multi-class cancer classification and informative genes selection.","date":"2013","source":"BMC medical genomics","url":"https://pubmed.ncbi.nlm.nih.gov/23445528","citation_count":28,"is_preprint":false},{"pmid":"34305453","id":"PMC_34305453","title":"BMSCs Regulate Astrocytes through TSG-6 to Protect the Blood-Brain Barrier after Subarachnoid Hemorrhage.","date":"2021","source":"Mediators of inflammation","url":"https://pubmed.ncbi.nlm.nih.gov/34305453","citation_count":26,"is_preprint":false},{"pmid":"17307731","id":"PMC_17307731","title":"Determining the molecular basis for the pH-dependent interaction between the link module of human TSG-6 and hyaluronan.","date":"2007","source":"The Journal of biological chemistry","url":"https://pubmed.ncbi.nlm.nih.gov/17307731","citation_count":26,"is_preprint":false}],"cost":{"stage1":{"model":"claude-sonnet-4-6","input_tokens":54881,"output_tokens":1328,"usd":0.092282},"stage2":{"model":"claude-opus-4-6","input_tokens":4545,"output_tokens":1681,"usd":0.097125},"total_usd":0.189407,"stage1_batch_id":"msgbatch_01RPbVc9PDH9zQmYK5Hs6srm","stage2_batch_id":"msgbatch_01JVbVLzeKN2yVrsGp3zC8aM","note":"batch pricing = 50% of standard"},"stage1_raw":"```json\n{\n  \"discoveries\": [\n    {\n      \"year\": 2009,\n      \"finding\": \"TWSG1 (twisted gastrulation protein) suppresses hepcidin expression in human hepatocytes by inhibiting BMP2/BMP4 signaling; in murine hepatocytes it suppresses hepcidin even in the absence of exogenous BMP, identifying it as an erythroid-derived regulator of iron homeostasis\",\n      \"method\": \"Hepcidin suppression assays (quantitative PCR), dosed recombinant TWSG1 protein treatment of primary hepatocyte cultures, transcriptome analysis of erythropoiesis stages\",\n      \"journal\": \"Blood\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 — multiple orthogonal methods (functional suppression assays with dose-response, pathway placement via BMP inhibition, in vivo thalassemic mouse model), moderate evidence from single lab\",\n      \"pmids\": [\"19414861\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2005,\n      \"finding\": \"Drosophila Tsg (ortholog of TWSG1) forms a ternary complex with Sog/chordin and BMP ligands (Dpp/Scw heterodimer), facilitating long-range transport of the Dpp/Scw heterodimer to dorsal-most cells; Tsg and Sog are essential for this transport, and the Dpp/Scw heterodimer signals synergistically through two type I BMP receptors (Tkv and Sax)\",\n      \"method\": \"Genetic epistasis, biochemical co-immunoprecipitation, cell-based signaling assays, mathematical modeling\",\n      \"journal\": \"Cell\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1-2 — biochemical and genetic evidence combined, highly cited foundational paper\",\n      \"pmids\": [\"15797386\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2003,\n      \"finding\": \"Drosophila Tsg sensitizes the BMP patterning mechanism to low levels of Dpp by forming complexes with Sog and Dpp; Tsg promotes Sog cleavage by Tld in a Dpp concentration-dependent manner, creating a positive-negative reinforcement loop that sharpens the Dpp signaling boundary\",\n      \"method\": \"Cell-based signaling assays, genetic analysis, biochemical interaction assays\",\n      \"journal\": \"Development\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 — multiple biochemical and genetic methods, replicated in context of prior Drosophila work\",\n      \"pmids\": [\"12925593\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2005,\n      \"finding\": \"Loss of Bmp7 combined with reduction or loss of Tsg (mouse ortholog of TWSG1) causes sirenomelia due to defective ventroposterior mesoderm formation; Bmp7 binds directly to Tsg, and co-injection of Tsg and Bmp7 morpholinos in Xenopus synergistically inhibits ventral mesoderm formation, demonstrating that TWSG1/Tsg modulates BMP7 signaling in dorsoventral patterning of posterior mesoderm\",\n      \"method\": \"Mouse genetic compound mutant analysis, Xenopus morpholino knockdown, molecular marker studies, direct binding assay\",\n      \"journal\": \"Development\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1-2 — genetic epistasis in two model organisms plus direct binding evidence\",\n      \"pmids\": [\"15843411\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2013,\n      \"finding\": \"TWSG1/Tsg enhances endothelial cell sprouting, migration, and proliferation in a concentration-dependent manner via Akt, Erk, and Smad signaling; paradoxically, silencing of Tsg also increases these activities; Tsg and BMPER interact antagonistically/synergistically to balance BMP pathway activity required for normal zebrafish vascular development\",\n      \"method\": \"Matrigel sprouting assay, siRNA knockdown, in vivo zebrafish vascular development, signaling pathway analysis (western blot for Akt/Erk/Smad), mouse Matrigel plug assay\",\n      \"journal\": \"Journal of cell science\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 — multiple in vitro and in vivo methods but concentration-dependent biphasic effect adds interpretive complexity\",\n      \"pmids\": [\"23641068\"],\n      \"is_preprint\": false\n    }\n  ],\n  \"current_model\": \"TWSG1 (twisted gastrulation protein 1) is a secreted BMP-binding modulator that suppresses hepcidin expression in hepatocytes by antagonizing BMP2/BMP4 signaling, acts during erythropoiesis to regulate iron homeostasis (potentially dysregulating it in thalassemia), and in model organisms (Drosophila, mouse, Xenopus) forms extracellular complexes with chordin/Sog and BMP ligands to control BMP gradient formation, dorsoventral patterning, and vascular development.\"\n}\n```","stage2_raw":"```json\n{\n  \"mechanistic_narrative\": \"TWSG1 encodes a secreted BMP-binding glycoprotein that modulates BMP signaling gradients through formation of extracellular complexes with chordin/Sog and BMP ligands (Dpp, BMP7, BMP2/4), functioning as both a facilitator of long-range BMP ligand transport and a sensitizer of BMP gradient sharpening via concentration-dependent promotion of chordin/Sog cleavage by tolloid-family metalloproteinases [PMID:15797386, PMID:12925593]. In vertebrates, TWSG1 cooperates with BMP7 to pattern ventroposterior mesoderm, as demonstrated by sirenomelia in Bmp7/Tsg compound-mutant mice and synergistic ventral mesoderm loss in Xenopus morpholino co-injection experiments [PMID:15843411]. TWSG1 also functions as an erythroid-derived suppressor of hepcidin expression in hepatocytes by antagonizing BMP2/BMP4 signaling, linking it to systemic iron homeostasis regulation [PMID:19414861].\",\n  \"teleology\": [\n    {\n      \"year\": 2003,\n      \"claim\": \"Establishing that Tsg/TWSG1 is not simply an inhibitor or activator of BMP signaling but instead sensitizes the system to low BMP levels by forming ternary complexes with Sog and Dpp, and by promoting concentration-dependent Sog cleavage by Tld — thereby sharpening signaling boundaries.\",\n      \"evidence\": \"Cell-based signaling assays, genetic analysis, and biochemical interaction assays in Drosophila\",\n      \"pmids\": [\"12925593\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\n        \"Structural basis of Tsg-Sog-BMP ternary complex formation not resolved\",\n        \"Whether the positive-negative reinforcement loop operates identically in vertebrate systems was untested\"\n      ]\n    },\n    {\n      \"year\": 2005,\n      \"claim\": \"Two studies established that the Tsg/TWSG1 ternary complex has dual biological roles: facilitating long-range BMP heterodimer transport to peak-signaling regions (Drosophila) and cooperating with BMP7 to pattern ventroposterior mesoderm (mouse/Xenopus), the latter demonstrated by sirenomelia in compound mutants.\",\n      \"evidence\": \"Co-immunoprecipitation, genetic epistasis, and mathematical modeling in Drosophila; compound mutant analysis in mouse and morpholino knockdown in Xenopus with direct binding assays\",\n      \"pmids\": [\"15797386\", \"15843411\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\n        \"Whether TWSG1 transports BMP heterodimers in vertebrate embryos as it does in Drosophila was not directly tested\",\n        \"Identity of the relevant BMP heterodimer partners for TWSG1 in mammalian mesoderm patterning was incomplete\"\n      ]\n    },\n    {\n      \"year\": 2009,\n      \"claim\": \"TWSG1 was identified as an erythroid-derived BMP antagonist that suppresses hepcidin in hepatocytes, connecting its BMP-modulatory activity to systemic iron homeostasis and potentially to iron overload in thalassemia.\",\n      \"evidence\": \"Dose-response hepcidin suppression assays in primary human and murine hepatocytes, transcriptome profiling of erythropoiesis stages, thalassemic mouse model analysis\",\n      \"pmids\": [\"19414861\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\n        \"Whether TWSG1 acts on hepcidin through BMP2/4 receptor complex inhibition at the receptor level or through extracellular ligand sequestration was not mechanistically resolved\",\n        \"Contribution of TWSG1 relative to other erythroid hepcidin suppressors (e.g., ERFE) in vivo not established\"\n      ]\n    },\n    {\n      \"year\": 2013,\n      \"claim\": \"TWSG1 was shown to regulate endothelial sprouting, migration, and proliferation via Akt, Erk, and Smad pathways, with biphasic concentration-dependent effects and antagonistic/synergistic interplay with BMPER during vascular development.\",\n      \"evidence\": \"Matrigel sprouting assays, siRNA knockdown, zebrafish vascular development, western blot signaling analysis, mouse Matrigel plug assay\",\n      \"pmids\": [\"23641068\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\n        \"Biphasic dose-response complicates interpretation of whether TWSG1 is pro- or anti-angiogenic in physiological contexts\",\n        \"The molecular basis for TWSG1-BMPER antagonistic versus synergistic interplay is unresolved\",\n        \"Whether vascular phenotypes are BMP-receptor-dependent or involve alternative signaling pathways was not determined\"\n      ]\n    },\n    {\n      \"year\": null,\n      \"claim\": \"The structural basis of TWSG1 ternary complex formation with chordin and BMP ligands, the mechanism by which it discriminates between BMP family members (BMP2/4 vs BMP7), and its relative physiological contribution to hepcidin regulation versus other erythroid factors remain open questions.\",\n      \"evidence\": \"\",\n      \"pmids\": [],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\n        \"No high-resolution structure of a TWSG1-chordin-BMP complex exists\",\n        \"Selectivity determinants for different BMP ligand binding are unknown\",\n        \"In vivo contribution of TWSG1 to iron homeostasis versus other erythroid BMP antagonists has not been dissected genetically in mammals\"\n      ]\n    }\n  ],\n  \"mechanism_profile\": {\n    \"molecular_activity\": [\n      {\"term_id\": \"GO:0098772\", \"supporting_discovery_ids\": [0, 1, 2, 4]}\n    ],\n    \"localization\": [\n      {\"term_id\": \"GO:0005576\", \"supporting_discovery_ids\": [0, 1, 2, 3]}\n    ],\n    \"pathway\": [\n      {\"term_id\": \"R-HSA-162582\", \"supporting_discovery_ids\": [0, 1, 2, 3, 4]},\n      {\"term_id\": \"R-HSA-1266738\", \"supporting_discovery_ids\": [1, 2, 3]}\n    ],\n    \"complexes\": [],\n    \"partners\": [\n      \"BMP7\",\n      \"BMP2\",\n      \"BMP4\",\n      \"CHRD\",\n      \"BMPER\"\n    ],\n    \"other_free_text\": []\n  }\n}\n```"}