{"gene":"DTX2","run_date":"2026-06-09T23:54:42","timeline":{"discoveries":[{"year":2024,"finding":"DTX2 binds to NCOA4 and facilitates its ubiquitination and degradation via K48-linked polyubiquitin chains, suppressing NCOA4-driven ferritinophagy and ferroptosis in non-small cell lung cancer cells.","method":"Co-immunoprecipitation, ubiquitination assay, knockdown/overexpression with ferroptosis readouts","journal":"Drug resistance updates","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — reciprocal binding and ubiquitination assays in one lab, two orthogonal methods (Co-IP + ubiquitination), single study","pmids":["39366066"],"is_preprint":false},{"year":2024,"finding":"DTX2 is rapidly recruited to DNA double-strand break sites in a poly-ADP-ribosylation-dependent manner, via its WWE and DELTEX conserved C-terminal domains. DTX2 depletion decreases homologous recombination efficiency, moderately enhances NHEJ, impedes BRCA1 foci formation, and increases 53BP1 accumulation at DSBs, indicating a role in DNA repair pathway choice.","method":"Localization screen with microirradiation, domain deletion analysis, HR/NHEJ reporter assays, immunofluorescence of BRCA1 and 53BP1 foci, cancer cell sensitization to X-rays and PARP inhibition with rescue by re-expression","journal":"The Journal of biological chemistry","confidence":"High","confidence_rationale":"Tier 2 / Strong — multiple orthogonal methods (localization screen, domain mutants, functional HR/NHEJ assays, rescue experiments) in a single rigorous study","pmids":["38992439"],"is_preprint":false},{"year":2025,"finding":"DTX2 ubiquitinates HSD17B4 at its SCP structural domain at K645 via K48-linked chains through its RING domain, leading to proteasomal degradation of HSD17B4, reduction of peroxisomal β-oxidation, decreased DHA-phospholipid levels, and suppression of ferroptosis in hepatocellular carcinoma cells. DTX2 expression is upregulated by JAK2-STAT3 pathway activation in Lenvatinib-resistant cells.","method":"CRISPR screen, in vitro and in vivo ubiquitination assays, domain mutagenesis, lipid metabolomics, DHA supplementation rescue, STAT3 pathway inhibition","journal":"Drug resistance updates","confidence":"High","confidence_rationale":"Tier 1-2 / Strong — CRISPR identification, in vitro ubiquitination with site-specific mutagenesis (K645), lipid metabolic readout, rescue experiment, multiple orthogonal methods in one study","pmids":["40058099"],"is_preprint":false},{"year":2022,"finding":"DTX2 promotes hTERT transcription by mediating K63-linked ubiquitination of transcription factor NFIC, which facilitates NFIC binding to the hTERT promoter and enhances hTERT expression. DTX2 depletion downregulates hTERT transcription and telomerase activity, leading to progressive telomere shortening, growth arrest, and apoptosis in telomerase-positive cancer cells.","method":"CRISPR/Cas9 KO screen with hTERT promoter reporter, BioID proximity labeling, ubiquitination assay (K63-linkage), ChIP analysis of NFIC promoter binding, telomerase activity assay","journal":"iScience","confidence":"High","confidence_rationale":"Tier 2 / Strong — CRISPR screen, BioID, ubiquitination linkage specificity assay, ChIP, and functional telomerase readouts, multiple orthogonal methods in one study","pmids":["35198878"],"is_preprint":false},{"year":2024,"finding":"DTX2 acts as an E3 ubiquitin ligase for FTO (fat mass and obesity-associated protein), ubiquitinating it followed by UFD1 recruitment and proteasomal degradation. VES (vitamin E succinate) binds both FTO and DTX2, enhancing the FTO-DTX2 interaction and promoting FTO ubiquitination and degradation.","method":"Co-immunoprecipitation (FTO-DTX2 interaction), ubiquitination assay, binding assay (VES to FTO and DTX2), genetic FTO knockdown and VES treatment in vivo with m6A methylation readout","journal":"Proceedings of the National Academy of Sciences of the United States of America","confidence":"High","confidence_rationale":"Tier 2 / Strong — Co-IP, ubiquitination assay, VES binding assay, in vivo mouse model validation, multiple orthogonal methods","pmids":["39661064"],"is_preprint":false},{"year":2023,"finding":"DTX2 binds to RUNX1 (and RUNX2/RUNX3) through their C-terminal regions. DTX2-induced ubiquitination of RUNX1 does not cause its proteasomal degradation but instead inhibits RUNX1 acetylation (which normally enhances RUNX1 transcriptional activity), reduces RUNX1-mediated transcriptional activation of an MCSFR reporter, and induces RUNX1 cytoplasmic mislocalization. DTX2 overexpression inhibits growth of RUNX1-dependent leukemia cell lines.","method":"Cell-free AlphaScreen binding assay, in vitro ubiquitination assay, acetylation assay, luciferase reporter assay (MCSFR promoter), immunofluorescence for localization, cell growth assay in leukemia lines","journal":"The FEBS journal","confidence":"High","confidence_rationale":"Tier 2 / Strong — multiple orthogonal methods (binding assay, ubiquitination, acetylation, reporter, localization, growth) in a single rigorous study","pmids":["37500075"],"is_preprint":false},{"year":2024,"finding":"DTX2 ubiquitinates HLTF (helicase-like transcription factor), promoting its degradation, and thereby promoting glioma cell proliferation and migration. DTX2 and HLTF co-immunoprecipitate and co-localize.","method":"Co-immunoprecipitation, confocal co-localization, in vitro ubiquitination assay, knockdown/overexpression with proliferation/migration assays, in vivo xenograft model","journal":"Biology direct","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — Co-IP, in vitro ubiquitination assay, and functional readouts in one lab, single study","pmids":["38163902"],"is_preprint":false},{"year":2023,"finding":"DTX2 overexpression promotes migration and invasion of colorectal cancer cells through activation of the Notch2/Akt axis, evidenced by increased Notch2, NICD, p-Akt, and MMP-2/9 protein levels; Notch2 siRNA reversed the pro-migratory effect of DTX2 overexpression.","method":"shRNA knockdown and overexpression, scratch/Transwell assays, Western blotting for Notch2/NICD/p-AKT/MMP proteins, epistasis by Notch2 siRNA co-transfection","journal":"Nan fang yi ke da xue xue bao","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — genetic epistasis (Notch2 siRNA rescue), multiple protein readouts, single lab","pmids":["37087577"],"is_preprint":false},{"year":2024,"finding":"In zebrafish, Dtx2 deficiency induces ependymo-radial glial cell proliferation and improves spinal cord motor function recovery after injury. This effect is mediated via activation of Notch-Rbpj signaling, as dominant-negative Rbpj abolished the increased ependymo-radial glia proliferation caused by Dtx2 deficiency.","method":"Heterozygous dtx2 mutant zebrafish, motor function assays post-injury, cell proliferation assays, dominant-negative Rbpj epistasis experiment, her gene expression analysis","journal":"Stem cells and development","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — genetic epistasis with dominant-negative Rbpj, loss-of-function in zebrafish with defined cellular and functional readout, single lab","pmids":["39001828"],"is_preprint":false},{"year":2006,"finding":"DTX2 encodes a 622-amino-acid protein containing two WWE domains and a C-terminal RING-finger domain, located on human chromosome 7q11.23. Northern analysis showed expression in fetal and adult heart tissue.","method":"RACE cDNA cloning, Northern blot, bioinformatic domain analysis","journal":"DNA sequence","confidence":"Low","confidence_rationale":"Tier 3 / Weak — cDNA cloning and domain identification, single method, no functional validation","pmids":["17286044"],"is_preprint":false},{"year":2025,"finding":"DTX2 generates the initial MARUbe (monoubiquitylation of mono-ADP-ribose) on PARP7 in cells, depending on PARP7 catalytic activity. This MARUbe is then extended with K11-linked polyubiquitin by RNF114.","method":"Cell-based ubiquitination assay, PARP7 catalytic mutant, click chemistry-inspired chemoenzymatic Ub-ADPr probe, co-immunoprecipitation","journal":"bioRxiv","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — cell-based assay with catalytic mutant control and novel chemical probe, single lab, preprint not yet peer-reviewed","pmids":["bio_10.1101_2025.05.11.653360"],"is_preprint":true},{"year":2025,"finding":"DTX2 (and DTX3) catalyze monoubiquitylation of tankyrase on mono-ADP-ribose (not canonical lysine), creating a monoubiquitin-MAR hybrid mark that prevents PAR formation and stabilizes tankyrase by antagonizing RNF146-mediated degradation.","method":"Cell-based ubiquitination assay, tankyrase ADP-ribosylation site mapping, functional stabilization assay","journal":"bioRxiv","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — cell-based ubiquitination assay with mechanistic follow-up, single lab, preprint not yet peer-reviewed","pmids":["bio_10.1101_2025.04.09.648013"],"is_preprint":true},{"year":2024,"finding":"PARP7 mono-ADP-ribosylates the androgen receptor (AR) on Cys620 within its DNA binding domain, and this ADP-ribosyl degron is recognized by the ADP-ribose reader domain of DTX2, leading to non-conventional (lysine-independent) ubiquitin conjugation to ADP-ribosyl-cysteine and proteasomal degradation of AR, forming a negative feedback loop on AR-dependent gene expression.","method":"Biochemical ubiquitination assay, AR Cys620 mutant analysis, nuclear import-competent/DNA binding-deficient AR mutant, mathematical modeling validated in cells, proteasome inhibitor experiments","journal":"bioRxiv","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — site-specific mutagenesis, mutant AR cellular validation, multiple orthogonal approaches, single lab, preprint not yet peer-reviewed","pmids":["bio_10.1101_2024.12.21.629908"],"is_preprint":true},{"year":2025,"finding":"AutoMARylation of PARP7 promotes its instability through an E3 ligase-ubiquitin-proteasome pathway mediated by DTX2 (and RNF114), linking NAD+ sensing to PARP7 protein turnover.","method":"Genetic depletion of PARP7, DTX2, and RNF114; autoMARylation assay; proteasome inhibitor experiments in adipogenesis context","journal":"bioRxiv","confidence":"Low","confidence_rationale":"Tier 3 / Weak — single mention of DTX2 role in PARP7 degradation pathway, preprint, limited mechanistic detail specific to DTX2 in the abstract","pmids":["bio_10.1101_2025.04.07.647692"],"is_preprint":true}],"current_model":"DTX2 is a RING/WWE domain E3 ubiquitin ligase that ubiquitinates diverse substrates (NCOA4, HSD17B4, HLTF, NFIC, FTO, RUNX1, PARP7, tankyrase, androgen receptor) through both conventional K48- and K63-linked polyubiquitin chains and unconventional ubiquitylation of ADP-ribose moieties, with its WWE domains mediating ADP-ribosylation-dependent recruitment to DNA damage sites and substrate recognition, enabling roles in ferroptosis regulation, DNA double-strand break repair pathway choice (promoting homologous recombination), telomerase transcription, Notch/RUNX signaling modulation, and negative feedback of androgen receptor signaling."},"narrative":{"mechanistic_narrative":"DTX2 is a RING/WWE-domain E3 ubiquitin ligase that controls the abundance and activity of diverse substrates through both conventional lysine-linked polyubiquitin chains and unconventional ubiquitylation of ADP-ribose, thereby regulating ferroptosis, DNA repair, telomerase transcription, and Notch/RUNX signaling [PMID:38992439, PMID:40058099, PMID:35198878]. Through its RING domain it assembles K48-linked chains that drive proteasomal degradation of NCOA4, HSD17B4, HLTF, and FTO, suppressing ferritinophagy-driven and peroxisomal lipid-dependent ferroptosis and modulating m6A demethylation [PMID:39366066, PMID:40058099, PMID:39661064, PMID:38163902]. In contrast, DTX2-mediated K63-linked ubiquitination of the transcription factor NFIC promotes its binding to the hTERT promoter, sustaining telomerase activity and telomere length in cancer cells [PMID:35198878]. DTX2 can also ubiquitinate substrates non-degradatively: it modifies RUNX1 to block its acetylation and induce cytoplasmic mislocalization, restraining RUNX1 transcriptional output [PMID:37500075]. Its WWE/DELTEX ADP-ribose reader domains recruit DTX2 to poly-ADP-ribosylated DNA double-strand breaks, where it promotes BRCA1 foci formation and homologous recombination at the expense of NHEJ, sensitizing cells to PARP inhibition when depleted [PMID:38992439]. The same ADP-ribose-recognition capacity enables a distinct chemistry in which DTX2 ubiquitylates ADP-ribose moieties directly — generating monoubiquitin-MAR marks on PARP7 and tankyrase and recognizing PARP7-installed ADP-ribosyl degrons on the androgen receptor to drive lysine-independent AR degradation [PMID:bio_10.1101_2025.05.11.653360, PMID:bio_10.1101_2025.04.09.648013, PMID:bio_10.1101_2024.12.21.629908]. DTX2 additionally influences Notch signaling outputs in cancer cell migration and zebrafish glial proliferation [PMID:37087577, PMID:39001828].","teleology":[{"year":2006,"claim":"Established the basic architecture of DTX2 as a candidate E3 ligase, defining the domains that would later prove functionally central.","evidence":"RACE cDNA cloning, Northern blot, and bioinformatic domain analysis identifying two WWE domains and a C-terminal RING finger","pmids":["17286044"],"confidence":"Low","gaps":["No functional validation of ligase activity","No substrate or pathway identified","Tissue expression beyond heart not characterized"]},{"year":2022,"claim":"Showed DTX2 uses K63-linked, non-degradative ubiquitination to activate a transcription factor, revealing it does more than mark proteins for destruction.","evidence":"CRISPR KO screen with hTERT reporter, BioID, K63-linkage ubiquitination assay, NFIC ChIP, and telomerase activity readouts","pmids":["35198878"],"confidence":"High","gaps":["Ubiquitination site on NFIC not mapped","How K63 chains promote promoter binding mechanistically unresolved"]},{"year":2023,"claim":"Demonstrated DTX2 can ubiquitinate substrates to alter their activity and localization rather than degrade them, expanding its regulatory repertoire into transcription factor control.","evidence":"AlphaScreen binding, in vitro ubiquitination, acetylation assay, MCSFR reporter, and localization/growth assays in RUNX1-dependent leukemia lines","pmids":["37500075"],"confidence":"High","gaps":["Ubiquitin chain linkage on RUNX1 not defined","Mechanism linking ubiquitination to acetylation blockade unclear"]},{"year":2023,"claim":"Linked DTX2 to Notch-pathway-dependent cancer cell migration, connecting it to canonical Notch signaling outputs.","evidence":"shRNA/overexpression, migration/invasion assays, Notch2/NICD/p-AKT/MMP western blots, and Notch2 siRNA epistasis in colorectal cancer cells","pmids":["37087577"],"confidence":"Medium","gaps":["No direct molecular target of DTX2 in the Notch2 axis identified","Ligase-activity dependence not tested"]},{"year":2024,"claim":"Established DTX2 as a PAR-recruited regulator of DNA double-strand break repair pathway choice, tying its WWE/DELTEX domains to genome stability and PARP-inhibitor sensitivity.","evidence":"Microirradiation localization screen, domain-deletion analysis, HR/NHEJ reporters, BRCA1/53BP1 foci imaging, and X-ray/PARPi sensitization with rescue","pmids":["38992439"],"confidence":"High","gaps":["Direct substrate at DSBs not identified","Whether ligase catalytic activity is required for HR promotion unresolved"]},{"year":2024,"claim":"Identified DTX2 as a suppressor of NCOA4-driven ferritinophagy and ferroptosis via K48-linked degradation, defining a ferroptosis-regulatory role.","evidence":"Co-IP, ubiquitination assay, and knockdown/overexpression with ferroptosis readouts in non-small cell lung cancer cells","pmids":["39366066"],"confidence":"Medium","gaps":["NCOA4 ubiquitination site not mapped","Single study without reciprocal in vivo confirmation"]},{"year":2024,"claim":"Extended the ferroptosis-suppressor role to a second substrate and metabolic axis, with DTX2 targeting HSD17B4 to limit peroxisomal lipid metabolism in drug-resistant tumors.","evidence":"CRISPR screen, in vitro/in vivo ubiquitination with K645 site mutagenesis, lipid metabolomics, DHA rescue, and STAT3 inhibition in hepatocellular carcinoma","pmids":["40058099"],"confidence":"High","gaps":["Generality of JAK2-STAT3 induction across tumor types untested","Relative contribution of NCOA4 vs HSD17B4 axes not compared"]},{"year":2024,"claim":"Showed DTX2 targets the m6A demethylase FTO for UFD1-coupled proteasomal degradation, connecting it to RNA modification and a small-molecule (VES) modulator.","evidence":"Co-IP, ubiquitination assay, VES binding assay, and in vivo FTO knockdown/VES treatment with m6A readouts","pmids":["39661064"],"confidence":"High","gaps":["FTO ubiquitination site not mapped","Mechanism of UFD1 recruitment by DTX2 unresolved"]},{"year":2024,"claim":"Demonstrated DTX2 targets HLTF for degradation to promote glioma growth, broadening its degradative substrate set in cancer.","evidence":"Co-IP, confocal co-localization, in vitro ubiquitination, proliferation/migration assays, and xenograft model","pmids":["38163902"],"confidence":"Medium","gaps":["Ubiquitin linkage type on HLTF undefined","Single-lab study"]},{"year":2024,"claim":"Provided an in vivo developmental context, showing Dtx2 restrains glial proliferation and spinal cord recovery through Notch-Rbpj signaling.","evidence":"Heterozygous dtx2 zebrafish, post-injury motor and proliferation assays, and dominant-negative Rbpj epistasis","pmids":["39001828"],"confidence":"Medium","gaps":["Molecular substrate linking Dtx2 to Rbpj output unknown","Relationship to mammalian DTX2 function untested"]},{"year":2025,"claim":"Revealed an unconventional catalytic activity in which DTX2 ubiquitylates ADP-ribose moieties directly, generating hybrid marks on PARP7, tankyrase, and the androgen receptor that govern protein stability and signaling feedback.","evidence":"Cell-based ubiquitination assays with catalytic/site mutants, chemoenzymatic Ub-ADPr probes, ADP-ribosylation site mapping, and AR Cys620 mutant analysis (preprints)","pmids":["bio_10.1101_2025.05.11.653360","bio_10.1101_2025.04.09.648013","bio_10.1101_2024.12.21.629908"],"confidence":"Medium","gaps":["Findings remain in preprints not yet peer-reviewed","Structural basis for ADP-ribose-directed ubiquitin transfer unresolved","Generality of the MARUbe mechanism across substrates untested"]},{"year":null,"claim":"How DTX2 selects between K48 degradative, K63 non-degradative, and ADP-ribose-directed ubiquitylation on different substrates, and what governs its substrate specificity, remains unresolved.","evidence":"No single study in the corpus reconciles the divergent chain-type outcomes mechanistically","pmids":[],"confidence":"Low","gaps":["No structural model of substrate or ADP-ribose engagement","Determinants of chain-type choice unknown","Physiological hierarchy among the many reported substrates undefined"]}],"mechanism_profile":{"molecular_activity":[{"term_id":"GO:0016740","term_label":"transferase activity","supporting_discovery_ids":[0,2,3,4,5,6]},{"term_id":"GO:0140096","term_label":"catalytic activity, acting on a protein","supporting_discovery_ids":[0,2,5,6]},{"term_id":"GO:0016874","term_label":"ligase activity","supporting_discovery_ids":[2,3,4,5]}],"localization":[{"term_id":"GO:0005634","term_label":"nucleus","supporting_discovery_ids":[3,5]},{"term_id":"GO:0000228","term_label":"nuclear chromosome","supporting_discovery_ids":[1]}],"pathway":[{"term_id":"R-HSA-73894","term_label":"DNA Repair","supporting_discovery_ids":[1]},{"term_id":"R-HSA-5357801","term_label":"Programmed Cell Death","supporting_discovery_ids":[0,2]},{"term_id":"R-HSA-392499","term_label":"Metabolism of proteins","supporting_discovery_ids":[0,2,4,6]},{"term_id":"R-HSA-162582","term_label":"Signal Transduction","supporting_discovery_ids":[7,8]},{"term_id":"R-HSA-74160","term_label":"Gene expression (Transcription)","supporting_discovery_ids":[3,5]}],"complexes":[],"partners":["NCOA4","HSD17B4","HLTF","NFIC","FTO","RUNX1","PARP7","AR"],"other_free_text":[]}},"prefetch_data":{"uniprot":{"accession":"Q86UW9","full_name":"Probable E3 ubiquitin-protein ligase DTX2","aliases":["Protein deltex-2","Deltex2","hDTX2","RING finger protein 58","RING-type E3 ubiquitin transferase DTX2"],"length_aa":622,"mass_kda":67.2,"function":"Regulator of Notch signaling, a signaling pathway involved in cell-cell communications that regulates a broad spectrum of cell-fate determinations. Probably acts both as a positive and negative regulator of Notch, depending on the developmental and cell context. Mediates the antineural activity of Notch, possibly by inhibiting the transcriptional activation mediated by MATCH1. Functions as a ubiquitin ligase protein in vitro, suggesting that it may regulate the Notch pathway via some ubiquitin ligase activity","subcellular_location":"Cytoplasm; Nucleus","url":"https://www.uniprot.org/uniprotkb/Q86UW9/entry"},"depmap":{"release":"DepMap","has_data":true,"is_common_essential":false,"resolved_as":"","url":"https://depmap.org/portal/gene/DTX2","classification":"Not Classified","n_dependent_lines":111,"n_total_lines":1208,"dependency_fraction":0.09188741721854304},"opencell":{"profiled":false,"resolved_as":"","ensg_id":"","cell_line_id":"","localizations":[],"interactors":[],"url":"https://opencell.sf.czbiohub.org/search/DTX2","total_profiled":1310},"omim":[{"mim_id":"613141","title":"DELTEX E3 UBIQUITIN LIGASE 2; DTX2","url":"https://www.omim.org/entry/613141"},{"mim_id":"612659","title":"REGULATORY FACTOR X, 6; RFX6","url":"https://www.omim.org/entry/612659"}],"hpa":{"profiled":true,"resolved_as":"","reliability":"Supported","locations":[{"location":"Nucleoplasm","reliability":"Supported"},{"location":"Nuclear membrane","reliability":"Supported"},{"location":"Vesicles","reliability":"Additional"},{"location":"Plasma membrane","reliability":"Additional"},{"location":"Cytosol","reliability":"Additional"}],"tissue_specificity":"Tissue enhanced","tissue_distribution":"Detected in all","driving_tissues":[{"tissue":"esophagus","ntpm":51.1}],"url":"https://www.proteinatlas.org/search/DTX2"},"hgnc":{"alias_symbol":["RNF58","KIAA1528"],"prev_symbol":[]},"alphafold":{"accession":"Q86UW9","domains":[{"cath_id":"3.30.720.50","chopping":"19-51_61-184","consensus_level":"medium","plddt":90.1678,"start":19,"end":184},{"cath_id":"3.30.40.10","chopping":"394-477","consensus_level":"high","plddt":92.3817,"start":394,"end":477},{"cath_id":"3.30.390.130","chopping":"488-619","consensus_level":"high","plddt":93.5314,"start":488,"end":619}],"viewer_url":"https://alphafold.ebi.ac.uk/entry/Q86UW9","model_url":"https://alphafold.ebi.ac.uk/files/AF-Q86UW9-F1-model_v6.cif","pae_url":"https://alphafold.ebi.ac.uk/files/AF-Q86UW9-F1-predicted_aligned_error_v6.png","plddt_mean":71.81},"mouse_models":{"mgi_url":"https://www.informatics.jax.org/marker/summary?nomen=DTX2","jax_strain_url":"https://www.jax.org/strain/search?query=DTX2"},"sequence":{"accession":"Q86UW9","fasta_url":"https://rest.uniprot.org/uniprotkb/Q86UW9.fasta","uniprot_url":"https://www.uniprot.org/uniprotkb/Q86UW9/entry","alphafold_viewer_url":"https://alphafold.ebi.ac.uk/entry/Q86UW9"}},"corpus_meta":[{"pmid":"39366066","id":"PMC_39366066","title":"E3 ubiquitin ligase DTX2 fosters ferroptosis resistance via suppressing NCOA4-mediated ferritinophagy in non-small cell lung cancer.","date":"2024","source":"Drug resistance updates : reviews and commentaries in antimicrobial and anticancer chemotherapy","url":"https://pubmed.ncbi.nlm.nih.gov/39366066","citation_count":36,"is_preprint":false},{"pmid":"38992439","id":"PMC_38992439","title":"An E3 ubiquitin ligase localization screen uncovers DTX2 as a novel ADP-ribosylation-dependent regulator of DNA double-strand break repair.","date":"2024","source":"The Journal of biological chemistry","url":"https://pubmed.ncbi.nlm.nih.gov/38992439","citation_count":17,"is_preprint":false},{"pmid":"40058099","id":"PMC_40058099","title":"DTX2 attenuates Lenvatinib-induced ferroptosis by suppressing docosahexaenoic acid biosynthesis through HSD17B4-dependent peroxisomal β-oxidation in hepatocellular carcinoma.","date":"2025","source":"Drug resistance updates : reviews and commentaries in antimicrobial and anticancer chemotherapy","url":"https://pubmed.ncbi.nlm.nih.gov/40058099","citation_count":13,"is_preprint":false},{"pmid":"35198878","id":"PMC_35198878","title":"An inducible CRISPR/Cas9 screen identifies DTX2 as a transcriptional regulator of human telomerase.","date":"2022","source":"iScience","url":"https://pubmed.ncbi.nlm.nih.gov/35198878","citation_count":12,"is_preprint":false},{"pmid":"22661044","id":"PMC_22661044","title":"Acute myeloid leukemia with t(7;21)(q11.2;q22) expresses a novel, reversed-sequence RUNX1-DTX2 chimera.","date":"2012","source":"International journal of hematology","url":"https://pubmed.ncbi.nlm.nih.gov/22661044","citation_count":10,"is_preprint":false},{"pmid":"39661064","id":"PMC_39661064","title":"Targeting DTX2/UFD1-mediated FTO degradation to regulate antitumor immunity.","date":"2024","source":"Proceedings of the National Academy of Sciences of the United States of 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Journal of Southern Medical University","url":"https://pubmed.ncbi.nlm.nih.gov/40294933","citation_count":0,"is_preprint":false},{"pmid":null,"id":"bio_10.1101_2025.05.11.653360","title":"A family of E3 ligases extend K11 polyubiquitin on sites of MARUbylation","date":"2025-05-15","source":"bioRxiv","url":"https://doi.org/10.1101/2025.05.11.653360","citation_count":0,"is_preprint":true},{"pmid":null,"id":"bio_10.1101_2025.04.09.648013","title":"Deltex and RING-UIM E3 ligases cooperate to create a ubiquitin-ADP-ribose hybrid mark on tankyrase, promoting its stabilization","date":"2025-04-09","source":"bioRxiv","url":"https://doi.org/10.1101/2025.04.09.648013","citation_count":0,"is_preprint":true},{"pmid":null,"id":"bio_10.1101_2025.04.07.647692","title":"NAD  <sup>+</sup>  Sensing by PARP7 Regulates the C/EBPβ-Dependent Transcription Program in Adipose Tissue In Vivo","date":"2025-04-08","source":"bioRxiv","url":"https://doi.org/10.1101/2025.04.07.647692","citation_count":0,"is_preprint":true},{"pmid":null,"id":"bio_10.1101_2024.12.21.629908","title":"Parp7 generates an ADP-ribosyl degron that controls negative feedback of androgen signaling","date":"2024-12-22","source":"bioRxiv","url":"https://doi.org/10.1101/2024.12.21.629908","citation_count":0,"is_preprint":true}],"cost":{"stage1":{"model":"claude-sonnet-4-6","input_tokens":10785,"output_tokens":3755,"usd":0.04434,"stage1_stop_reason":"end_turn"},"stage2":{"model":"claude-opus-4-8","input_tokens":11393,"output_tokens":4023,"usd":0.07877,"stage2_stop_reason":"end_turn"},"total_usd":0.12311,"stage1_batch_id":"msgbatch_01AsR7g8dGTEiEw9U83bJeWn","stage2_batch_id":"msgbatch_01YV5ZyxtFNUZEjxRcpd9jzb","note":"batch pricing = 50% of standard"},"stage1_raw":"```json\n{\n  \"discoveries\": [\n    {\n      \"year\": 2024,\n      \"finding\": \"DTX2 binds to NCOA4 and facilitates its ubiquitination and degradation via K48-linked polyubiquitin chains, suppressing NCOA4-driven ferritinophagy and ferroptosis in non-small cell lung cancer cells.\",\n      \"method\": \"Co-immunoprecipitation, ubiquitination assay, knockdown/overexpression with ferroptosis readouts\",\n      \"journal\": \"Drug resistance updates\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — reciprocal binding and ubiquitination assays in one lab, two orthogonal methods (Co-IP + ubiquitination), single study\",\n      \"pmids\": [\"39366066\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2024,\n      \"finding\": \"DTX2 is rapidly recruited to DNA double-strand break sites in a poly-ADP-ribosylation-dependent manner, via its WWE and DELTEX conserved C-terminal domains. DTX2 depletion decreases homologous recombination efficiency, moderately enhances NHEJ, impedes BRCA1 foci formation, and increases 53BP1 accumulation at DSBs, indicating a role in DNA repair pathway choice.\",\n      \"method\": \"Localization screen with microirradiation, domain deletion analysis, HR/NHEJ reporter assays, immunofluorescence of BRCA1 and 53BP1 foci, cancer cell sensitization to X-rays and PARP inhibition with rescue by re-expression\",\n      \"journal\": \"The Journal of biological chemistry\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — multiple orthogonal methods (localization screen, domain mutants, functional HR/NHEJ assays, rescue experiments) in a single rigorous study\",\n      \"pmids\": [\"38992439\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2025,\n      \"finding\": \"DTX2 ubiquitinates HSD17B4 at its SCP structural domain at K645 via K48-linked chains through its RING domain, leading to proteasomal degradation of HSD17B4, reduction of peroxisomal β-oxidation, decreased DHA-phospholipid levels, and suppression of ferroptosis in hepatocellular carcinoma cells. DTX2 expression is upregulated by JAK2-STAT3 pathway activation in Lenvatinib-resistant cells.\",\n      \"method\": \"CRISPR screen, in vitro and in vivo ubiquitination assays, domain mutagenesis, lipid metabolomics, DHA supplementation rescue, STAT3 pathway inhibition\",\n      \"journal\": \"Drug resistance updates\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1-2 / Strong — CRISPR identification, in vitro ubiquitination with site-specific mutagenesis (K645), lipid metabolic readout, rescue experiment, multiple orthogonal methods in one study\",\n      \"pmids\": [\"40058099\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2022,\n      \"finding\": \"DTX2 promotes hTERT transcription by mediating K63-linked ubiquitination of transcription factor NFIC, which facilitates NFIC binding to the hTERT promoter and enhances hTERT expression. DTX2 depletion downregulates hTERT transcription and telomerase activity, leading to progressive telomere shortening, growth arrest, and apoptosis in telomerase-positive cancer cells.\",\n      \"method\": \"CRISPR/Cas9 KO screen with hTERT promoter reporter, BioID proximity labeling, ubiquitination assay (K63-linkage), ChIP analysis of NFIC promoter binding, telomerase activity assay\",\n      \"journal\": \"iScience\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — CRISPR screen, BioID, ubiquitination linkage specificity assay, ChIP, and functional telomerase readouts, multiple orthogonal methods in one study\",\n      \"pmids\": [\"35198878\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2024,\n      \"finding\": \"DTX2 acts as an E3 ubiquitin ligase for FTO (fat mass and obesity-associated protein), ubiquitinating it followed by UFD1 recruitment and proteasomal degradation. VES (vitamin E succinate) binds both FTO and DTX2, enhancing the FTO-DTX2 interaction and promoting FTO ubiquitination and degradation.\",\n      \"method\": \"Co-immunoprecipitation (FTO-DTX2 interaction), ubiquitination assay, binding assay (VES to FTO and DTX2), genetic FTO knockdown and VES treatment in vivo with m6A methylation readout\",\n      \"journal\": \"Proceedings of the National Academy of Sciences of the United States of America\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — Co-IP, ubiquitination assay, VES binding assay, in vivo mouse model validation, multiple orthogonal methods\",\n      \"pmids\": [\"39661064\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2023,\n      \"finding\": \"DTX2 binds to RUNX1 (and RUNX2/RUNX3) through their C-terminal regions. DTX2-induced ubiquitination of RUNX1 does not cause its proteasomal degradation but instead inhibits RUNX1 acetylation (which normally enhances RUNX1 transcriptional activity), reduces RUNX1-mediated transcriptional activation of an MCSFR reporter, and induces RUNX1 cytoplasmic mislocalization. DTX2 overexpression inhibits growth of RUNX1-dependent leukemia cell lines.\",\n      \"method\": \"Cell-free AlphaScreen binding assay, in vitro ubiquitination assay, acetylation assay, luciferase reporter assay (MCSFR promoter), immunofluorescence for localization, cell growth assay in leukemia lines\",\n      \"journal\": \"The FEBS journal\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — multiple orthogonal methods (binding assay, ubiquitination, acetylation, reporter, localization, growth) in a single rigorous study\",\n      \"pmids\": [\"37500075\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2024,\n      \"finding\": \"DTX2 ubiquitinates HLTF (helicase-like transcription factor), promoting its degradation, and thereby promoting glioma cell proliferation and migration. DTX2 and HLTF co-immunoprecipitate and co-localize.\",\n      \"method\": \"Co-immunoprecipitation, confocal co-localization, in vitro ubiquitination assay, knockdown/overexpression with proliferation/migration assays, in vivo xenograft model\",\n      \"journal\": \"Biology direct\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — Co-IP, in vitro ubiquitination assay, and functional readouts in one lab, single study\",\n      \"pmids\": [\"38163902\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2023,\n      \"finding\": \"DTX2 overexpression promotes migration and invasion of colorectal cancer cells through activation of the Notch2/Akt axis, evidenced by increased Notch2, NICD, p-Akt, and MMP-2/9 protein levels; Notch2 siRNA reversed the pro-migratory effect of DTX2 overexpression.\",\n      \"method\": \"shRNA knockdown and overexpression, scratch/Transwell assays, Western blotting for Notch2/NICD/p-AKT/MMP proteins, epistasis by Notch2 siRNA co-transfection\",\n      \"journal\": \"Nan fang yi ke da xue xue bao\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — genetic epistasis (Notch2 siRNA rescue), multiple protein readouts, single lab\",\n      \"pmids\": [\"37087577\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2024,\n      \"finding\": \"In zebrafish, Dtx2 deficiency induces ependymo-radial glial cell proliferation and improves spinal cord motor function recovery after injury. This effect is mediated via activation of Notch-Rbpj signaling, as dominant-negative Rbpj abolished the increased ependymo-radial glia proliferation caused by Dtx2 deficiency.\",\n      \"method\": \"Heterozygous dtx2 mutant zebrafish, motor function assays post-injury, cell proliferation assays, dominant-negative Rbpj epistasis experiment, her gene expression analysis\",\n      \"journal\": \"Stem cells and development\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — genetic epistasis with dominant-negative Rbpj, loss-of-function in zebrafish with defined cellular and functional readout, single lab\",\n      \"pmids\": [\"39001828\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2006,\n      \"finding\": \"DTX2 encodes a 622-amino-acid protein containing two WWE domains and a C-terminal RING-finger domain, located on human chromosome 7q11.23. Northern analysis showed expression in fetal and adult heart tissue.\",\n      \"method\": \"RACE cDNA cloning, Northern blot, bioinformatic domain analysis\",\n      \"journal\": \"DNA sequence\",\n      \"confidence\": \"Low\",\n      \"confidence_rationale\": \"Tier 3 / Weak — cDNA cloning and domain identification, single method, no functional validation\",\n      \"pmids\": [\"17286044\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2025,\n      \"finding\": \"DTX2 generates the initial MARUbe (monoubiquitylation of mono-ADP-ribose) on PARP7 in cells, depending on PARP7 catalytic activity. This MARUbe is then extended with K11-linked polyubiquitin by RNF114.\",\n      \"method\": \"Cell-based ubiquitination assay, PARP7 catalytic mutant, click chemistry-inspired chemoenzymatic Ub-ADPr probe, co-immunoprecipitation\",\n      \"journal\": \"bioRxiv\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — cell-based assay with catalytic mutant control and novel chemical probe, single lab, preprint not yet peer-reviewed\",\n      \"pmids\": [\"bio_10.1101_2025.05.11.653360\"],\n      \"is_preprint\": true\n    },\n    {\n      \"year\": 2025,\n      \"finding\": \"DTX2 (and DTX3) catalyze monoubiquitylation of tankyrase on mono-ADP-ribose (not canonical lysine), creating a monoubiquitin-MAR hybrid mark that prevents PAR formation and stabilizes tankyrase by antagonizing RNF146-mediated degradation.\",\n      \"method\": \"Cell-based ubiquitination assay, tankyrase ADP-ribosylation site mapping, functional stabilization assay\",\n      \"journal\": \"bioRxiv\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — cell-based ubiquitination assay with mechanistic follow-up, single lab, preprint not yet peer-reviewed\",\n      \"pmids\": [\"bio_10.1101_2025.04.09.648013\"],\n      \"is_preprint\": true\n    },\n    {\n      \"year\": 2024,\n      \"finding\": \"PARP7 mono-ADP-ribosylates the androgen receptor (AR) on Cys620 within its DNA binding domain, and this ADP-ribosyl degron is recognized by the ADP-ribose reader domain of DTX2, leading to non-conventional (lysine-independent) ubiquitin conjugation to ADP-ribosyl-cysteine and proteasomal degradation of AR, forming a negative feedback loop on AR-dependent gene expression.\",\n      \"method\": \"Biochemical ubiquitination assay, AR Cys620 mutant analysis, nuclear import-competent/DNA binding-deficient AR mutant, mathematical modeling validated in cells, proteasome inhibitor experiments\",\n      \"journal\": \"bioRxiv\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — site-specific mutagenesis, mutant AR cellular validation, multiple orthogonal approaches, single lab, preprint not yet peer-reviewed\",\n      \"pmids\": [\"bio_10.1101_2024.12.21.629908\"],\n      \"is_preprint\": true\n    },\n    {\n      \"year\": 2025,\n      \"finding\": \"AutoMARylation of PARP7 promotes its instability through an E3 ligase-ubiquitin-proteasome pathway mediated by DTX2 (and RNF114), linking NAD+ sensing to PARP7 protein turnover.\",\n      \"method\": \"Genetic depletion of PARP7, DTX2, and RNF114; autoMARylation assay; proteasome inhibitor experiments in adipogenesis context\",\n      \"journal\": \"bioRxiv\",\n      \"confidence\": \"Low\",\n      \"confidence_rationale\": \"Tier 3 / Weak — single mention of DTX2 role in PARP7 degradation pathway, preprint, limited mechanistic detail specific to DTX2 in the abstract\",\n      \"pmids\": [\"bio_10.1101_2025.04.07.647692\"],\n      \"is_preprint\": true\n    }\n  ],\n  \"current_model\": \"DTX2 is a RING/WWE domain E3 ubiquitin ligase that ubiquitinates diverse substrates (NCOA4, HSD17B4, HLTF, NFIC, FTO, RUNX1, PARP7, tankyrase, androgen receptor) through both conventional K48- and K63-linked polyubiquitin chains and unconventional ubiquitylation of ADP-ribose moieties, with its WWE domains mediating ADP-ribosylation-dependent recruitment to DNA damage sites and substrate recognition, enabling roles in ferroptosis regulation, DNA double-strand break repair pathway choice (promoting homologous recombination), telomerase transcription, Notch/RUNX signaling modulation, and negative feedback of androgen receptor signaling.\"\n}\n```","stage2_raw":"{\n  \"mechanistic_narrative\": \"DTX2 is a RING/WWE-domain E3 ubiquitin ligase that controls the abundance and activity of diverse substrates through both conventional lysine-linked polyubiquitin chains and unconventional ubiquitylation of ADP-ribose, thereby regulating ferroptosis, DNA repair, telomerase transcription, and Notch/RUNX signaling [#1, #2, #3]. Through its RING domain it assembles K48-linked chains that drive proteasomal degradation of NCOA4, HSD17B4, HLTF, and FTO, suppressing ferritinophagy-driven and peroxisomal lipid-dependent ferroptosis and modulating m6A demethylation [#0, #2, #4, #6]. In contrast, DTX2-mediated K63-linked ubiquitination of the transcription factor NFIC promotes its binding to the hTERT promoter, sustaining telomerase activity and telomere length in cancer cells [#3]. DTX2 can also ubiquitinate substrates non-degradatively: it modifies RUNX1 to block its acetylation and induce cytoplasmic mislocalization, restraining RUNX1 transcriptional output [#5]. Its WWE/DELTEX ADP-ribose reader domains recruit DTX2 to poly-ADP-ribosylated DNA double-strand breaks, where it promotes BRCA1 foci formation and homologous recombination at the expense of NHEJ, sensitizing cells to PARP inhibition when depleted [#1]. The same ADP-ribose-recognition capacity enables a distinct chemistry in which DTX2 ubiquitylates ADP-ribose moieties directly — generating monoubiquitin-MAR marks on PARP7 and tankyrase and recognizing PARP7-installed ADP-ribosyl degrons on the androgen receptor to drive lysine-independent AR degradation [#10, #11, #12]. DTX2 additionally influences Notch signaling outputs in cancer cell migration and zebrafish glial proliferation [#7, #8].\",\n  \"teleology\": [\n    {\n      \"year\": 2006,\n      \"claim\": \"Established the basic architecture of DTX2 as a candidate E3 ligase, defining the domains that would later prove functionally central.\",\n      \"evidence\": \"RACE cDNA cloning, Northern blot, and bioinformatic domain analysis identifying two WWE domains and a C-terminal RING finger\",\n      \"pmids\": [\"17286044\"],\n      \"confidence\": \"Low\",\n      \"gaps\": [\"No functional validation of ligase activity\", \"No substrate or pathway identified\", \"Tissue expression beyond heart not characterized\"]\n    },\n    {\n      \"year\": 2022,\n      \"claim\": \"Showed DTX2 uses K63-linked, non-degradative ubiquitination to activate a transcription factor, revealing it does more than mark proteins for destruction.\",\n      \"evidence\": \"CRISPR KO screen with hTERT reporter, BioID, K63-linkage ubiquitination assay, NFIC ChIP, and telomerase activity readouts\",\n      \"pmids\": [\"35198878\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Ubiquitination site on NFIC not mapped\", \"How K63 chains promote promoter binding mechanistically unresolved\"]\n    },\n    {\n      \"year\": 2023,\n      \"claim\": \"Demonstrated DTX2 can ubiquitinate substrates to alter their activity and localization rather than degrade them, expanding its regulatory repertoire into transcription factor control.\",\n      \"evidence\": \"AlphaScreen binding, in vitro ubiquitination, acetylation assay, MCSFR reporter, and localization/growth assays in RUNX1-dependent leukemia lines\",\n      \"pmids\": [\"37500075\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Ubiquitin chain linkage on RUNX1 not defined\", \"Mechanism linking ubiquitination to acetylation blockade unclear\"]\n    },\n    {\n      \"year\": 2023,\n      \"claim\": \"Linked DTX2 to Notch-pathway-dependent cancer cell migration, connecting it to canonical Notch signaling outputs.\",\n      \"evidence\": \"shRNA/overexpression, migration/invasion assays, Notch2/NICD/p-AKT/MMP western blots, and Notch2 siRNA epistasis in colorectal cancer cells\",\n      \"pmids\": [\"37087577\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"No direct molecular target of DTX2 in the Notch2 axis identified\", \"Ligase-activity dependence not tested\"]\n    },\n    {\n      \"year\": 2024,\n      \"claim\": \"Established DTX2 as a PAR-recruited regulator of DNA double-strand break repair pathway choice, tying its WWE/DELTEX domains to genome stability and PARP-inhibitor sensitivity.\",\n      \"evidence\": \"Microirradiation localization screen, domain-deletion analysis, HR/NHEJ reporters, BRCA1/53BP1 foci imaging, and X-ray/PARPi sensitization with rescue\",\n      \"pmids\": [\"38992439\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Direct substrate at DSBs not identified\", \"Whether ligase catalytic activity is required for HR promotion unresolved\"]\n    },\n    {\n      \"year\": 2024,\n      \"claim\": \"Identified DTX2 as a suppressor of NCOA4-driven ferritinophagy and ferroptosis via K48-linked degradation, defining a ferroptosis-regulatory role.\",\n      \"evidence\": \"Co-IP, ubiquitination assay, and knockdown/overexpression with ferroptosis readouts in non-small cell lung cancer cells\",\n      \"pmids\": [\"39366066\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"NCOA4 ubiquitination site not mapped\", \"Single study without reciprocal in vivo confirmation\"]\n    },\n    {\n      \"year\": 2024,\n      \"claim\": \"Extended the ferroptosis-suppressor role to a second substrate and metabolic axis, with DTX2 targeting HSD17B4 to limit peroxisomal lipid metabolism in drug-resistant tumors.\",\n      \"evidence\": \"CRISPR screen, in vitro/in vivo ubiquitination with K645 site mutagenesis, lipid metabolomics, DHA rescue, and STAT3 inhibition in hepatocellular carcinoma\",\n      \"pmids\": [\"40058099\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Generality of JAK2-STAT3 induction across tumor types untested\", \"Relative contribution of NCOA4 vs HSD17B4 axes not compared\"]\n    },\n    {\n      \"year\": 2024,\n      \"claim\": \"Showed DTX2 targets the m6A demethylase FTO for UFD1-coupled proteasomal degradation, connecting it to RNA modification and a small-molecule (VES) modulator.\",\n      \"evidence\": \"Co-IP, ubiquitination assay, VES binding assay, and in vivo FTO knockdown/VES treatment with m6A readouts\",\n      \"pmids\": [\"39661064\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"FTO ubiquitination site not mapped\", \"Mechanism of UFD1 recruitment by DTX2 unresolved\"]\n    },\n    {\n      \"year\": 2024,\n      \"claim\": \"Demonstrated DTX2 targets HLTF for degradation to promote glioma growth, broadening its degradative substrate set in cancer.\",\n      \"evidence\": \"Co-IP, confocal co-localization, in vitro ubiquitination, proliferation/migration assays, and xenograft model\",\n      \"pmids\": [\"38163902\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Ubiquitin linkage type on HLTF undefined\", \"Single-lab study\"]\n    },\n    {\n      \"year\": 2024,\n      \"claim\": \"Provided an in vivo developmental context, showing Dtx2 restrains glial proliferation and spinal cord recovery through Notch-Rbpj signaling.\",\n      \"evidence\": \"Heterozygous dtx2 zebrafish, post-injury motor and proliferation assays, and dominant-negative Rbpj epistasis\",\n      \"pmids\": [\"39001828\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Molecular substrate linking Dtx2 to Rbpj output unknown\", \"Relationship to mammalian DTX2 function untested\"]\n    },\n    {\n      \"year\": 2025,\n      \"claim\": \"Revealed an unconventional catalytic activity in which DTX2 ubiquitylates ADP-ribose moieties directly, generating hybrid marks on PARP7, tankyrase, and the androgen receptor that govern protein stability and signaling feedback.\",\n      \"evidence\": \"Cell-based ubiquitination assays with catalytic/site mutants, chemoenzymatic Ub-ADPr probes, ADP-ribosylation site mapping, and AR Cys620 mutant analysis (preprints)\",\n      \"pmids\": [\"bio_10.1101_2025.05.11.653360\", \"bio_10.1101_2025.04.09.648013\", \"bio_10.1101_2024.12.21.629908\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Findings remain in preprints not yet peer-reviewed\", \"Structural basis for ADP-ribose-directed ubiquitin transfer unresolved\", \"Generality of the MARUbe mechanism across substrates untested\"]\n    },\n    {\n      \"year\": null,\n      \"claim\": \"How DTX2 selects between K48 degradative, K63 non-degradative, and ADP-ribose-directed ubiquitylation on different substrates, and what governs its substrate specificity, remains unresolved.\",\n      \"evidence\": \"No single study in the corpus reconciles the divergent chain-type outcomes mechanistically\",\n      \"pmids\": [],\n      \"confidence\": \"Low\",\n      \"gaps\": [\"No structural model of substrate or ADP-ribose engagement\", \"Determinants of chain-type choice unknown\", \"Physiological hierarchy among the many reported substrates undefined\"]\n    }\n  ],\n  \"mechanism_profile\": {\n    \"molecular_activity\": [\n      {\"term_id\": \"GO:0016740\", \"supporting_discovery_ids\": [0, 2, 3, 4, 5, 6]},\n      {\"term_id\": \"GO:0140096\", \"supporting_discovery_ids\": [0, 2, 5, 6]},\n      {\"term_id\": \"GO:0016874\", \"supporting_discovery_ids\": [2, 3, 4, 5]}\n    ],\n    \"localization\": [\n      {\"term_id\": \"GO:0005634\", \"supporting_discovery_ids\": [3, 5]},\n      {\"term_id\": \"GO:0000228\", \"supporting_discovery_ids\": [1]}\n    ],\n    \"pathway\": [\n      {\"term_id\": \"R-HSA-73894\", \"supporting_discovery_ids\": [1]},\n      {\"term_id\": \"R-HSA-5357801\", \"supporting_discovery_ids\": [0, 2]},\n      {\"term_id\": \"R-HSA-392499\", \"supporting_discovery_ids\": [0, 2, 4, 6]},\n      {\"term_id\": \"R-HSA-162582\", \"supporting_discovery_ids\": [7, 8]},\n      {\"term_id\": \"R-HSA-74160\", \"supporting_discovery_ids\": [3, 5]}\n    ],\n    \"complexes\": [],\n    \"partners\": [\"NCOA4\", \"HSD17B4\", \"HLTF\", \"NFIC\", \"FTO\", \"RUNX1\", \"PARP7\", \"AR\"],\n    \"other_free_text\": []\n  }\n}","audit_flag":null,"evaluation":{"pairwise":"win","faith_supported":6,"faith_total":6,"faith_pct":100.0}}