{"gene":"TRAIP","run_date":"2026-06-10T10:51:55","timeline":{"discoveries":[{"year":2019,"finding":"TRAIP is an E3 ubiquitin ligase that ubiquitylates the CMG replicative helicase (CDC45-MCM2-7-GINS) when two replisomes converge at a DNA interstrand crosslink (ICL). Short ubiquitin chains on CMG recruit NEIL3 glycosylase (which can directly cleave the crosslink), whereas longer ubiquitin chains trigger CMG unloading by the p97 ATPase, enabling the Fanconi anaemia pathway. TRAIP thereby controls the choice between the two known pathways of replication-coupled ICL repair.","method":"Xenopus egg extract reconstitution; biochemical fractionation; ubiquitin chain-length analysis; NEIL3 binding assays; p97 inhibition; epistasis with Fanconi anaemia pathway mutants","journal":"Nature","confidence":"High","confidence_rationale":"Tier 1 / Strong — reconstituted in vitro in Xenopus extracts with multiple orthogonal methods (ubiquitylation assays, binding assays, p97 inhibition, pathway epistasis), single rigorous study with comprehensive mechanistic dissection","pmids":["30842657"],"is_preprint":false},{"year":2019,"finding":"TRAIP ubiquitin ligase drives replisome disassembly in response to incomplete DNA replication in mitosis (mitotic replisome disassembly), providing access to replication forks for other factors; TRAIP is also essential for mitotic DNA repair synthesis (MiDAS) in human cells, and its loss causes mitotic segregation errors.","method":"C. elegans embryo genetics; human cell knockdown; epistasis analysis; live imaging of chromosome segregation errors","journal":"eLife","confidence":"High","confidence_rationale":"Tier 2 / Strong — clean loss-of-function in two independent model systems (C. elegans and human cells) with defined phenotypic readouts (replisome retention, MiDAS defect, segregation errors)","pmids":["31545170"],"is_preprint":false},{"year":2019,"finding":"In Xenopus egg extracts, mitotic replisome disassembly depends on TRAIP-mediated formation of K6- and K63-linked ubiquitin chains on MCM7, followed by p97/VCP-dependent extraction. This pathway does not require SUMO modifications (unlike lower eukaryotes) and can remove all replisomes from mitotic chromatin, including stalled ones.","method":"Xenopus egg extract; ubiquitin linkage-specific analysis; p97 inhibition; SUMO pathway manipulation","journal":"Life science alliance","confidence":"High","confidence_rationale":"Tier 1 / Moderate — in vitro reconstitution in Xenopus extracts with linkage-specific ubiquitin chain analysis and p97 inhibition; single lab but multiple orthogonal methods","pmids":["30979826"],"is_preprint":false},{"year":2015,"finding":"TRAIP directly interacts with PCNA via a conserved PIP box motif and localizes to active and stressed replication forks. TRAIP promotes ATR-dependent checkpoint signaling by facilitating RPA-bound single-stranded DNA generation upon replication stress; this requires both E3 ligase activity and the PIP box. Loss of TRAIP leads to chromosomal instability and reduced cell survival after replication stress.","method":"Co-immunoprecipitation; PIP box mutagenesis; RPA-ssDNA accumulation assays; ATR signaling readouts (Chk1 phosphorylation); clonogenic survival; chromosomal instability analysis","journal":"The Journal of cell biology","confidence":"High","confidence_rationale":"Tier 2 / Moderate — reciprocal Co-IP, domain mutagenesis, and functional assays with multiple orthogonal readouts in a single rigorous study","pmids":["26711499"],"is_preprint":false},{"year":2015,"finding":"TRAIP (encoding an E3 RING ubiquitin ligase) relocalizes to sites of DNA damage during S-phase and is required for optimal phosphorylation of H2AX and RPA2 in response to UV irradiation, as well as for replication fork progression through UV-induced lesions. Mutations in TRAIP cause microcephalic primordial dwarfism.","method":"Patient genetic analysis; laser microirradiation/foci formation; H2AX and RPA2 phosphorylation assays; DNA fiber assays for fork progression; siRNA knockdown","journal":"Nature genetics","confidence":"High","confidence_rationale":"Tier 2 / Strong — multiple orthogonal functional readouts (foci, phosphorylation, fiber assays) combined with human genetics; replicated across patient cells and cell lines","pmids":["26595769"],"is_preprint":false},{"year":2016,"finding":"TRAIP is required for recruitment of RAP80 to DNA lesions; TRAIP acts upstream of RAP80 and downstream factors including BRCA1. The N-terminus of TRAIP mediates RAP80 interaction, while the C-terminus of TRAIP mediates localization to DNA damage sites through direct interaction with RNF20-RNF40. TRAIP thereby promotes homologous recombination.","method":"Co-immunoprecipitation; domain deletion analysis; laser microirradiation foci recruitment assays; siRNA knockdown; HR reporter assays","journal":"Nature communications","confidence":"High","confidence_rationale":"Tier 2 / Moderate — reciprocal Co-IP, domain mapping, and functional epistasis with multiple orthogonal methods in one study","pmids":["26781088"],"is_preprint":false},{"year":2016,"finding":"TRAIP encodes a nucleolar protein that migrates to stalled replication forks by targeting PCNA via an evolutionarily conserved PIP box on its C-terminus. Inactivation of TRAIP or disruption of the TRAIP-PCNA interaction compromises replication fork recovery and progression and causes chromosome instability.","method":"GFP-TRAIP live imaging; PIP box mutagenesis; PCNA interaction assays; DNA fiber assays; chromosomal instability analysis","journal":"Cell discovery","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — live imaging with PIP box mutagenesis and functional fork assays; single lab, overlapping findings with PMID:26711499","pmids":["27462463"],"is_preprint":false},{"year":2021,"finding":"In mouse embryonic stem cells, TRAIP ubiquitin ligase mediates a second (mitotic) pathway of CMG helicase disassembly in addition to the S-phase CUL2LRR1-dependent pathway. Both CUL2LRR1 and TRAIP target CMG for ubiquitylation and p97-dependent disassembly, establishing that metazoan replisome disassembly is controlled by a conserved pair of ubiquitin ligases.","method":"Mouse embryonic stem cell genetic knockouts; chromatin fractionation; ubiquitylation assays; cell cycle staging","journal":"EMBO reports","confidence":"High","confidence_rationale":"Tier 2 / Moderate — clean KO in mammalian cells with chromatin fractionation and ubiquitylation readouts; confirmed in mouse ESCs extending findings from Xenopus and C. elegans","pmids":["33590678"],"is_preprint":false},{"year":2014,"finding":"TRAIP localizes near mitotic chromosomes and its knockdown decreases early mitosis progression time and increases chromosome alignment defects and lagging chromosomes. TRAIP-depleted cells bypass taxol-induced mitotic arrest and show reduced kinetochore MAD2 levels, indicating that TRAIP E3 ubiquitin ligase activity is required for spindle assembly checkpoint control.","method":"RNAi knockdown in HeLa cells; live-cell imaging; flow cytometry; kinetochore immunofluorescence (MAD2); taxol/nocodazole treatment; rescue with wild-type vs. ubiquitin-ligase-dead TRAIP","journal":"Journal of cell science","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — clean RNAi knockdown with live imaging, rescue experiments (WT vs. catalytic mutant), and MAD2 kinetochore quantification; single lab","pmids":["25335891"],"is_preprint":false},{"year":2016,"finding":"TRAIP is post-translationally modified by SUMOylation at five sites; SUMOylation is required for nuclear retention and protein stability of TRAIP. SUMOylation-deficient TRAIP fails to be retained in the nucleus and exhibits reduced protein stability.","method":"SUMOylation site mutagenesis; subcellular fractionation; immunofluorescence; protein stability assays (cycloheximide chase)","journal":"Biochemical and biophysical research communications","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — mutagenesis of SUMOylation sites combined with fractionation and stability assays; single lab","pmids":["26820530"],"is_preprint":false},{"year":2018,"finding":"PRRRSV non-structural protein 1α (nsp1α) interacts with TRAIP at K205, decreases TRAIP SUMOylation and K48-linked ubiquitination, causing redistribution of TRAIP from nucleus to cytoplasm. Cytoplasmic TRAIP then promotes K48-linked ubiquitination and degradation of TBK1, antagonizing TBK1-IRF3-IFN signaling.","method":"Co-immunoprecipitation; site-directed mutagenesis (K205); subcellular fractionation; TBK1 ubiquitination assays; IFN signaling reporter assays","journal":"Frontiers in immunology","confidence":"Medium","confidence_rationale":"Tier 3 / Moderate — Co-IP with mutagenesis and functional ubiquitination assays; single lab, viral context","pmids":["30619364"],"is_preprint":false},{"year":2018,"finding":"The TRAIP coiled-coil domain interacts with the TRAF-N domain of TRAF2 (but not TRAF1) to inhibit NF-κB signaling. The coiled-coil domain alters stoichiometry between dimer and trimer in a concentration-dependent manner, and the RING domain induces higher-ordered assembly required for TRAF2 interaction.","method":"In vitro binding/biochemical characterization; domain deletion and mutagenesis; size-exclusion chromatography; pull-down assays","journal":"International journal of molecular sciences","confidence":"Medium","confidence_rationale":"Tier 1 / Weak — in vitro reconstitution with domain characterization; single lab, no cellular validation of the NF-κB mechanism","pmids":["30127245"],"is_preprint":false},{"year":2018,"finding":"TRAIP nucleolar residence is coupled to active ribosomal DNA transcription: RNA polymerase I inhibition or rDNA damage causes TRAIP to diffuse into the nucleoplasm. PCNA binding is dispensable for nucleolus-to-nucleoplasm shuttling after UV. Pre-treatment with DNase/RNase releases TRAIP from nucleoli, suggesting sequestration via nucleic acid structures.","method":"RNA polymerase I inhibition (CX-5461); I-PpoI-induced rDNA damage; DNase/RNase pre-treatment; live-cell imaging; PCNA PIP-box mutant analysis; ATM/ATR inhibition","journal":"Nucleic acids research","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — multiple perturbation approaches (chemical, enzymatic, genetic) with live imaging; single lab","pmids":["30165463"],"is_preprint":false},{"year":2015,"finding":"TRAIP forms homodimers through its coiled-coil (CC) domain; expression of a CC-domain-deleted mutant that cannot homodimerize increases mitotic index and promotes mitotic progression, indicating that homodimerization is required for proper mitotic regulation.","method":"Co-immunoprecipitation with TRAIP deletion mutants; mitotic index measurements; flow cytometry","journal":"Biochemical and biophysical research communications","confidence":"Medium","confidence_rationale":"Tier 3 / Moderate — Co-IP domain mapping with functional mitotic readout; single lab","pmids":["26093298"],"is_preprint":false},{"year":2019,"finding":"TRAIP promotes ionizing radiation-induced H2B monoubiquitination at K120; deletion of the RING domain or C-terminus of TRAIP abolishes this activity, establishing a role for TRAIP in regulating this histone mark in the DNA damage response.","method":"siRNA knockdown; TRAIP deletion mutants; Western blot for H2B-K120 ubiquitination after IR","journal":"Oncology reports","confidence":"Low","confidence_rationale":"Tier 3 / Weak — single lab, single method (Western blot with deletion mutants); no direct ubiquitination reconstitution","pmids":["30942468"],"is_preprint":false},{"year":2023,"finding":"TRAIP resolves replication-transcription conflicts specifically during S-phase; rapid TRAIP degradation in S-phase causes DNA damage at transcription start sites, G2 arrest, and cellular senescence. TRAIP's S-phase function in preventing replication-transcription conflicts is essential for cell proliferation.","method":"Auxin-induced degron system for rapid TRAIP degradation; cell cycle-specific depletion; γH2AX foci at transcription start sites; cell cycle analysis; senescence assays","journal":"Nature communications","confidence":"High","confidence_rationale":"Tier 2 / Moderate — auxin-induced degron for acute cell-cycle-specific depletion with multiple orthogonal readouts (DNA damage markers, cell cycle, senescence); single lab but rigorous system","pmids":["37604812"],"is_preprint":false},{"year":2021,"finding":"TRAIP promotes KANK1 polyubiquitination and subsequent proteasomal degradation, which downregulates IGFBP3 and activates AKT signaling in osteosarcoma cells.","method":"Co-immunoprecipitation; ubiquitination assays; Western blot for KANK1, IGFBP3, and AKT pathway; siRNA knockdown and overexpression","journal":"Cell death & disease","confidence":"Low","confidence_rationale":"Tier 3 / Weak — Co-IP and ubiquitination assay in cancer cell lines; single lab, no in vitro reconstitution","pmids":["34349117"],"is_preprint":false},{"year":2023,"finding":"TRAIP directly interacts with MYC and promotes K48-linked polyubiquitination at MYC K428 and K430, leading to proteasome-dependent MYC degradation and suppression of MYC transcriptional activity in bladder cancer cells. MYC in turn binds the TRAIP promoter, establishing a negative feedback loop.","method":"Co-immunoprecipitation; ubiquitination assays with K428/K430 mutagenesis; proteasome inhibition; MYC transcriptional activity reporter; ChIP for MYC at TRAIP promoter; rescue experiments","journal":"Oncogene","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — site-specific ubiquitination mutagenesis combined with ChIP and rescue experiments; single lab","pmids":["38123820"],"is_preprint":false},{"year":2023,"finding":"ZNF212 is a direct binding partner of TRAIP; mutual recruitment of TRAIP and ZNF212 to DNA damage sites is interdependent. ZNF212 depletion causes DDR and HR repair defects epistatic to TRAIP. In mESCs, Zfp212 acts upstream of both the NEIL3 and Fanconi anaemia ICL repair pathways. ZNF212 also directly interacts with NEIL3 and promotes its recruitment to ICL lesions.","method":"Co-immunoprecipitation (direct interaction); laser microirradiation foci recruitment; epistasis analysis in mESCs; ICL repair assays; NEIL3 recruitment assays","journal":"Nucleic acids research","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — reciprocal Co-IP with foci recruitment and genetic epistasis in two cell systems; single lab","pmids":["36594163"],"is_preprint":false},{"year":2025,"finding":"CDK phosphorylation of TRAIP in mitosis is essential for mitotic replisome unloading and MiDAS. TRAIP interacts with terminated replisomes in S-phase without ubiquitylating them; CDK phosphorylation specifically activates TRAIP's autoubiquitylation and ubiquitylation of replisomes isolated from mitotic chromatin. CDK-driven phosphorylation alone is not sufficient to activate replisome unloading during S-phase.","method":"Auxin-induced degron; CDK inhibition; phospho-mimetic/non-phosphorylatable TRAIP mutants; in vitro ubiquitylation assays with mitotic chromatin; MiDAS assays in human cells","journal":"Nucleic acids research","confidence":"High","confidence_rationale":"Tier 1-2 / Moderate — in vitro ubiquitylation reconstitution with phospho-mutants combined with cell-based functional assays (MiDAS); single lab with multiple orthogonal methods","pmids":["40637231"],"is_preprint":false},{"year":2025,"finding":"USP37 deubiquitylase binds CMG helicase (via CDC45 contact) and counteracts TRAIP-dependent CMG ubiquitylation and premature replisome disassembly. In Xenopus extracts depleted of USP37, TRAIP promotes premature CMG ubiquitylation and disassembly when converging replisomes stall. TRAIP loss suppresses the hypersensitivity of USP37 knockout cells to topoisomerase inhibitors.","method":"Xenopus egg extract depletion; Usp37 knockout cells; genetic epistasis (TRAIP mutation suppressing USP37 KO phenotype); CMG ubiquitylation assays; structure-guided CDC45-binding mutations","journal":"Nature communications","confidence":"High","confidence_rationale":"Tier 1-2 / Strong — Xenopus reconstitution combined with mammalian KO genetics and epistasis; replicated across two independent studies (PMID:40533495 and PMID:40411782)","pmids":["40533495","40411782"],"is_preprint":false},{"year":2024,"finding":"TRAIP phosphorylation by mitotic Cyclin B-CDK1 enables formation of a complex with TTF2 (a SWI/SNF ATPase) and DNA polymerase ε. TTF2 tethers TRAIP to replisomes via an N-terminal zinc finger that binds phosphorylated TRAIP and an adjacent peptide that contacts the CMG-associated leading strand DNA polymerase ε (Pol2/POLE2). This TRAIP-TTF2-Pol ε bridge is essential for CMG unloading and stalled fork breakage in mitosis, independently of TTF2 ATPase activity.","method":"Xenopus egg extract; AlphaFold-Multimer-guided mutagenesis; biochemical reconstitution; TTF2 zinc finger binding assays; CDK1 phosphorylation of TRAIP; CMG unloading assays; MiDAS assays","journal":"bioRxiv","confidence":"High","confidence_rationale":"Tier 1-2 / Strong — structure-guided mutagenesis combined with Xenopus reconstitution; replicated in two independent preprint studies (bio_10.1101_2024.11.30.626186 and bio_10.1101_2024.12.01.626218)","pmids":["bio_10.1101_2024.11.30.626186","bio_10.1101_2024.12.01.626218"],"is_preprint":true},{"year":2025,"finding":"TRAIP depletion causes retention of PCNA on chromatin during mitosis; TRAIP-depleted cells entering G1 with chromatin-bound PCNA display reduced Cdt1 levels and impaired S-phase entry, and show delayed S-phase progression. TRAIP functions independently of ATAD5-RFC in PCNA unloading from chromatin.","method":"Auxin-induced degron for TRAIP depletion; chromatin fractionation; PCNA immunofluorescence; Cdt1 Western blot; S-phase entry assays; comparison with ATAD5-RFC-depleted cells","journal":"Genes to cells","confidence":"Medium","confidence_rationale":"Tier 2 / Weak — clean auxin degron with fractionation and functional readouts; single lab, single study","pmids":["39956965"],"is_preprint":false},{"year":2021,"finding":"In vitro, the TRAIP coiled-coil domain (residues 64-166) specifically forms a complex with the RAP80 zinc finger motif (residues 490-584); larger TRAIP fragments (CCLZ or RINGCC) fail to interact with the RAP80 zinc finger under the same conditions.","method":"In vitro protein-protein interaction assay; SDS-PAGE; co-elution","journal":"Saudi journal of biological sciences","confidence":"Low","confidence_rationale":"Tier 3 / Weak — single in vitro binding assay; single lab, no cellular validation of the specific domain interaction","pmids":["34867056"],"is_preprint":false},{"year":2026,"finding":"TRAIP functions as an E3 ubiquitin ligase that mediates K48-linked polyubiquitination and proteasomal degradation of PLSCR4 in breast cancer cells.","method":"Co-immunoprecipitation; K48-linked ubiquitination assays; rescue experiments with PLSCR4 knockdown","journal":"Journal of biochemical and molecular toxicology","confidence":"Low","confidence_rationale":"Tier 3 / Weak — single lab, Co-IP and ubiquitination assay in cancer cell lines without in vitro reconstitution","pmids":["41942828"],"is_preprint":false},{"year":2026,"finding":"SOX9 transcription factor directly binds the TRAIP promoter to drive its transcriptional upregulation. TRAIP then acts as the specific E3 ligase for CPEB3, mediating its poly-ubiquitylation and proteasomal degradation, which relieves CPEB3-mediated translational repression and hyperactivates mTORC1 signaling in gastric cancer cells.","method":"ChIP for SOX9 at TRAIP promoter; luciferase reporter assay; Co-immunoprecipitation; ubiquitylation assays; epistatic rescue experiments","journal":"World journal of surgical oncology","confidence":"Low","confidence_rationale":"Tier 3 / Weak — single lab, Co-IP and ubiquitination assay in cancer cell lines without in vitro reconstitution of direct ubiquitylation","pmids":["41832516"],"is_preprint":false}],"current_model":"TRAIP is a replisome-associated RING-domain E3 ubiquitin ligase that ubiquitylates the CMG replicative helicase (CDC45-MCM2-7-GINS) and interacts with PCNA via a conserved PIP box: during S-phase it promotes ATR-dependent checkpoint signaling, resolves replication-transcription conflicts, and — when two forks converge at a DNA interstrand crosslink — generates short ubiquitin chains that recruit NEIL3 glycosylase (prioritizing direct crosslink unhooking) or longer chains that recruit p97/VCP to unload CMG and enable the Fanconi anaemia pathway; in mitosis, CDK1-dependent phosphorylation activates TRAIP by enabling it to form a complex with TTF2 and DNA polymerase ε, which tethers TRAIP to stalled replisomes and drives CMG ubiquitylation (K6/K63-linked on MCM7) and p97-dependent disassembly of all residual replisomes, thereby facilitating MiDAS and preventing segregation errors; TRAIP activity is counterbalanced by the USP37 deubiquitylase that removes untimely CMG ubiquitylation; additionally, TRAIP is SUMOylated (required for nuclear localization and stability), homodimerizes via its coiled-coil domain, recruits RAP80/BRCA1 to lesions via an interaction with RNF20-RNF40, regulates the spindle assembly checkpoint by maintaining kinetochore MAD2 levels, and ubiquitylates non-replisome substrates such as MYC and KANK1 in specific cellular contexts."},"narrative":{"mechanistic_narrative":"TRAIP is a RING-domain E3 ubiquitin ligase that operates at the DNA replication machinery to safeguard genome integrity during S-phase and mitosis [PMID:30842657, PMID:26711499]. It localizes to active and stressed replication forks through a conserved PIP-box interaction with PCNA, where it promotes ATR-dependent checkpoint signaling and replication fork progression through DNA lesions; loss of TRAIP causes chromosomal instability, and biallelic mutations cause microcephalic primordial dwarfism [PMID:26711499, PMID:26595769]. At the heart of its activity, TRAIP ubiquitylates the CMG replicative helicase (CDC45-MCM2-7-GINS): when two forks converge at an interstrand crosslink, short ubiquitin chains recruit NEIL3 glycosylase to unhook the crosslink directly while longer chains trigger p97/VCP-dependent CMG unloading to license the Fanconi anaemia pathway, making TRAIP the switch between the two ICL repair routes [PMID:30842657]. In mitosis, TRAIP drives disassembly of all residual replisomes — including stalled ones — via K6/K63-linked ubiquitylation of MCM7 and p97-dependent extraction, an activity essential for mitotic DNA synthesis (MiDAS) and accurate chromosome segregation [PMID:31545170, PMID:30979826]. This mitotic activity is gated by Cyclin B-CDK1 phosphorylation, which licenses TRAIP autoubiquitylation and CMG ubiquitylation that it cannot perform on terminated replisomes in S-phase [PMID:40637231]; the opposing USP37 deubiquitylase removes untimely CMG ubiquitylation to prevent premature replisome disassembly [PMID:40533495, PMID:40411782]. TRAIP additionally resolves replication-transcription conflicts during S-phase, an activity required for continued proliferation [PMID:37604812], and it recruits RAP80/BRCA1 to lesions via RNF20-RNF40 to promote homologous recombination [PMID:26781088]. TRAIP is itself regulated by SUMOylation, which sustains its nuclear retention and stability [PMID:26820530], and homodimerizes through its coiled-coil domain to control mitotic progression [PMID:26093298]. Beyond the replisome, TRAIP ubiquitylates context-specific substrates including MYC and KANK1 [PMID:38123820, PMID:34349117].","teleology":[{"year":2014,"claim":"Established the first cellular role for TRAIP's catalytic activity by showing it is required for spindle assembly checkpoint integrity, linking the ligase to faithful mitosis.","evidence":"RNAi knockdown in HeLa cells with live imaging, kinetochore MAD2 quantification, and WT-versus-catalytic-dead rescue","pmids":["25335891"],"confidence":"Medium","gaps":["No direct ubiquitylation substrate identified at the kinetochore","Mechanism by which TRAIP maintains MAD2 levels unresolved","Single-lab observation"]},{"year":2015,"claim":"Tied TRAIP physically and functionally to the replisome by identifying a PCNA-binding PIP box and a requirement for both ligase activity and PCNA binding in ATR checkpoint signaling, defining TRAIP as a replication-stress factor.","evidence":"Reciprocal Co-IP, PIP-box mutagenesis, RPA-ssDNA and Chk1 phosphorylation readouts, clonogenic survival in human cells","pmids":["26711499"],"confidence":"High","gaps":["Direct ubiquitylation substrate during replication stress not yet defined","How PIP-box binding couples to ATR activation mechanistically unclear"]},{"year":2015,"claim":"Connected TRAIP to human disease and to lesion bypass, showing it relocalizes to damage in S-phase, supports H2AX/RPA2 phosphorylation and fork progression, and that mutations cause microcephalic primordial dwarfism.","evidence":"Patient genetics, laser microirradiation foci, phosphorylation assays, DNA fiber assays, siRNA","pmids":["26595769"],"confidence":"High","gaps":["Causal substrate linking TRAIP to the phosphorylation events not identified","Mechanism linking molecular defect to dwarfism phenotype unresolved"]},{"year":2016,"claim":"Placed TRAIP upstream in homologous recombination by mapping an N-terminal RAP80 interaction and a C-terminal RNF20-RNF40 interaction that recruits TRAIP to damage and feeds the RAP80/BRCA1 axis.","evidence":"Co-IP, domain deletion, laser microirradiation recruitment, HR reporter assays","pmids":["26781088","27462463"],"confidence":"High","gaps":["Whether RAP80/BRCA1 recruitment depends on TRAIP catalytic activity not fully resolved","Relationship between this HR role and the fork-protection role unclear"]},{"year":2016,"claim":"Identified post-translational and structural controls on TRAIP itself — SUMOylation for nuclear retention/stability and nucleolar residence coupled to active rDNA transcription.","evidence":"SUMO-site mutagenesis with fractionation and cycloheximide chase; RNA Pol I inhibition, rDNA damage, and DNase/RNase release with live imaging","pmids":["26820530","30165463"],"confidence":"Medium","gaps":["SUMO E3 ligase responsible for TRAIP modification unknown","Functional purpose of nucleolar sequestration not established"]},{"year":2019,"claim":"Defined TRAIP's central biochemical activity: ubiquitylation of the CMG helicase at converged forks, with chain length dictating the choice between NEIL3-mediated crosslink unhooking and p97-dependent CMG unloading into the Fanconi anaemia pathway.","evidence":"Xenopus egg extract reconstitution with chain-length analysis, NEIL3 binding, p97 inhibition, and Fanconi pathway epistasis","pmids":["30842657"],"confidence":"High","gaps":["How chain length is enzymatically tuned in vivo unclear","Reader specificity distinguishing short versus long chains not fully defined"]},{"year":2019,"claim":"Generalized TRAIP to a dedicated mitotic replisome-disassembly factor, showing it removes residual/stalled replisomes via K6/K63 chains on MCM7 and p97, and is essential for MiDAS and accurate segregation.","evidence":"C. elegans and human cell loss-of-function, Xenopus extract with linkage-specific ubiquitin analysis and p97 inhibition, live imaging of segregation errors","pmids":["31545170","30979826"],"confidence":"High","gaps":["Mechanism restricting this activity to mitosis not addressed in these studies","How K6/K63 chains are specified at MCM7 unknown"]},{"year":2021,"claim":"Positioned TRAIP within the broader replisome-disassembly framework, showing metazoans use a conserved pair of ligases (S-phase CUL2-LRR1 and mitotic TRAIP) for CMG unloading.","evidence":"Mouse ESC knockouts with chromatin fractionation, ubiquitylation assays, and cell-cycle staging","pmids":["33590678"],"confidence":"High","gaps":["Division of labor between the two ligases under different stress contexts not fully mapped"]},{"year":2023,"claim":"Established an S-phase-specific function in resolving replication-transcription conflicts essential for proliferation, distinguishing it from TRAIP's mitotic role.","evidence":"Auxin-induced degron for cell-cycle-specific depletion, gamma-H2AX at transcription start sites, cell cycle and senescence assays","pmids":["37604812"],"confidence":"High","gaps":["Direct substrate at conflict sites not identified","Whether CMG ubiquitylation underlies conflict resolution unclear"]},{"year":2024,"claim":"Solved how TRAIP is restricted to mitosis, showing CDK1 phosphorylation builds a TRAIP-TTF2-Pol epsilon bridge that tethers TRAIP to replisomes to drive CMG unloading and fork breakage.","evidence":"Xenopus extract with AlphaFold-Multimer-guided mutagenesis, TTF2 zinc-finger binding, CDK1 phosphorylation, CMG unloading and MiDAS assays (preprint)","pmids":["bio_10.1101_2024.11.30.626186","bio_10.1101_2024.12.01.626218"],"confidence":"High","gaps":["Awaits peer review","How the bridge selectively recognizes stalled versus active replisomes not fully resolved"]},{"year":2025,"claim":"Refined the cell-cycle gating model: CDK phosphorylation activates TRAIP autoubiquitylation and CMG ubiquitylation, and is necessary but not sufficient — TRAIP binds terminated replisomes in S-phase without ubiquitylating them.","evidence":"Auxin degron, CDK inhibition, phospho-mimetic/non-phosphorylatable mutants, in vitro ubiquitylation with mitotic chromatin, MiDAS assays","pmids":["40637231"],"confidence":"High","gaps":["The additional mitotic input beyond CDK phosphorylation not fully defined","Structural basis of activation not resolved"]},{"year":2025,"claim":"Identified the antagonist that constrains TRAIP timing: USP37 deubiquitylase binds CMG via CDC45 and reverses premature TRAIP-dependent CMG ubiquitylation, with TRAIP loss suppressing USP37-KO topoisomerase-inhibitor sensitivity.","evidence":"Xenopus extract depletion, USP37-knockout cells, genetic epistasis, CMG ubiquitylation assays, structure-guided CDC45-binding mutations","pmids":["40533495","40411782"],"confidence":"High","gaps":["How USP37 activity is itself temporally regulated unclear","Whether USP37 acts on mitotic as well as S-phase TRAIP activity not fully delineated"]},{"year":2023,"claim":"Extended TRAIP function to context-specific substrate ubiquitylation, identifying MYC as a direct K48-ubiquitylation target in a negative feedback loop and KANK1 in osteosarcoma signaling.","evidence":"Co-IP, site-specific ubiquitylation mutagenesis, ChIP, proteasome inhibition and rescue in cancer cell lines","pmids":["38123820","34349117"],"confidence":"Medium","gaps":["No in vitro reconstitution of direct ubiquitylation for KANK1","Relationship between these cancer-context substrates and the core replisome role unclear"]},{"year":null,"claim":"How TRAIP's distinct substrate selectivities (CMG, MYC, KANK1, histone marks) are coordinated and partitioned across S-phase, mitosis, and specific cellular contexts remains unresolved.","evidence":"","pmids":[],"confidence":"Medium","gaps":["No unifying determinant of substrate choice identified","Structural basis of the catalytic activation switch not solved","Mechanism connecting molecular defects to the dwarfism phenotype unknown"]}],"mechanism_profile":{"molecular_activity":[{"term_id":"GO:0016740","term_label":"transferase activity","supporting_discovery_ids":[0,2,3,17]},{"term_id":"GO:0140096","term_label":"catalytic activity, acting on a protein","supporting_discovery_ids":[0,2,17]},{"term_id":"GO:0016874","term_label":"ligase activity","supporting_discovery_ids":[0,5]}],"localization":[{"term_id":"GO:0005634","term_label":"nucleus","supporting_discovery_ids":[9]},{"term_id":"GO:0005730","term_label":"nucleolus","supporting_discovery_ids":[6,12]},{"term_id":"GO:0005694","term_label":"chromosome","supporting_discovery_ids":[1,2,22]}],"pathway":[{"term_id":"R-HSA-73894","term_label":"DNA Repair","supporting_discovery_ids":[0,4,5]},{"term_id":"R-HSA-69306","term_label":"DNA Replication","supporting_discovery_ids":[3,6,7]},{"term_id":"R-HSA-1640170","term_label":"Cell Cycle","supporting_discovery_ids":[1,8,19]},{"term_id":"R-HSA-392499","term_label":"Metabolism of proteins","supporting_discovery_ids":[0,2,17]}],"complexes":["CMG replicative helicase (substrate-bound)","TRAIP-TTF2-DNA polymerase epsilon"],"partners":["PCNA","TTF2","USP37","RAP80","RNF20","RNF40","ZNF212","MYC"],"other_free_text":[]}},"prefetch_data":{"uniprot":{"accession":"Q9BWF2","full_name":"E3 ubiquitin-protein ligase TRAIP","aliases":["RING finger protein 206","TRAF-interacting protein"],"length_aa":469,"mass_kda":53.3,"function":"E3 ubiquitin ligase required to protect genome stability in response to replication stress (PubMed:25335891, PubMed:26595769, PubMed:26711499, PubMed:26781088, PubMed:27462463, PubMed:31545170). Acts as a key regulator of interstrand cross-link repair, which takes place when both strands of duplex DNA are covalently tethered together, thereby blocking replication and transcription (By similarity). Controls the choice between the two pathways of replication-coupled interstrand-cross-link repair by mediating ubiquitination of MCM7 subunit of the CMG helicase complex (By similarity). Short ubiquitin chains on MCM7 promote recruitment of DNA glycosylase NEIL3 (By similarity). If the interstrand cross-link cannot be cleaved by NEIL3, the ubiquitin chains continue to grow on MCM7, promoting the unloading of the CMG helicase complex by the VCP/p97 ATPase, enabling the Fanconi anemia DNA repair pathway (By similarity). Only catalyzes ubiquitination of MCM7 when forks converge (By similarity). Also involved in the repair of covalent DNA-protein cross-links (DPCs) during DNA synthesis: promotes ubiquitination of DPCs, leading to their degradation by the proteasome (By similarity). Has also been proposed to play a role in promoting translesion synthesis by mediating the assembly of 'Lys-63'-linked poly-ubiquitin chains on the Y-family polymerase POLN in order to facilitate bypass of DNA lesions and preserve genomic integrity (PubMed:24553286). The function in translesion synthesis is however controversial (PubMed:26595769). Acts as a regulator of the spindle assembly checkpoint (PubMed:25335891). Also acts as a negative regulator of innate immune signaling by inhibiting activation of NF-kappa-B mediated by TNF (PubMed:22945920). Negatively regulates TLR3/4- and RIG-I-mediated IRF3 activation and subsequent IFNB1 production and cellular antiviral response by promoting 'Lys-48'-linked polyubiquitination of TNK1 leading to its proteasomal degradation (PubMed:22945920)","subcellular_location":"Nucleus, nucleoplasm; Nucleus, nucleolus; Chromosome; Cytoplasm; Cytoplasm, perinuclear region","url":"https://www.uniprot.org/uniprotkb/Q9BWF2/entry"},"depmap":{"release":"DepMap","has_data":true,"is_common_essential":true,"resolved_as":"","url":"https://depmap.org/portal/gene/TRAIP","classification":"Common Essential","n_dependent_lines":1016,"n_total_lines":1208,"dependency_fraction":0.8410596026490066},"opencell":{"profiled":false,"resolved_as":"","ensg_id":"","cell_line_id":"","localizations":[],"interactors":[],"url":"https://opencell.sf.czbiohub.org/search/TRAIP","total_profiled":1310},"omim":[{"mim_id":"616777","title":"SECKEL SYNDROME 9; SCKL9","url":"https://www.omim.org/entry/616777"},{"mim_id":"605958","title":"TRAF-INTERACTING PROTEIN; TRAIP","url":"https://www.omim.org/entry/605958"},{"mim_id":"210600","title":"SECKEL SYNDROME 1; SCKL1","url":"https://www.omim.org/entry/210600"}],"hpa":{"profiled":true,"resolved_as":"","reliability":"Supported","locations":[{"location":"Plasma membrane","reliability":"Supported"},{"location":"Cytosol","reliability":"Supported"}],"tissue_specificity":"Low tissue specificity","tissue_distribution":"Detected in many","driving_tissues":[],"url":"https://www.proteinatlas.org/search/TRAIP"},"hgnc":{"alias_symbol":["TRIP","RNF206"],"prev_symbol":[]},"alphafold":{"accession":"Q9BWF2","domains":[{"cath_id":"3.30.40.10","chopping":"2-66","consensus_level":"medium","plddt":85.6554,"start":2,"end":66},{"cath_id":"1.20.5","chopping":"76-174","consensus_level":"medium","plddt":96.527,"start":76,"end":174},{"cath_id":"1.20.5","chopping":"188-275","consensus_level":"medium","plddt":95.1033,"start":188,"end":275}],"viewer_url":"https://alphafold.ebi.ac.uk/entry/Q9BWF2","model_url":"https://alphafold.ebi.ac.uk/files/AF-Q9BWF2-F1-model_v6.cif","pae_url":"https://alphafold.ebi.ac.uk/files/AF-Q9BWF2-F1-predicted_aligned_error_v6.png","plddt_mean":74.94},"mouse_models":{"mgi_url":"https://www.informatics.jax.org/marker/summary?nomen=TRAIP","jax_strain_url":"https://www.jax.org/strain/search?query=TRAIP"},"sequence":{"accession":"Q9BWF2","fasta_url":"https://rest.uniprot.org/uniprotkb/Q9BWF2.fasta","uniprot_url":"https://www.uniprot.org/uniprotkb/Q9BWF2/entry","alphafold_viewer_url":"https://alphafold.ebi.ac.uk/entry/Q9BWF2"}},"corpus_meta":[{"pmid":"30842657","id":"PMC_30842657","title":"TRAIP 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JCU","url":"https://pubmed.ncbi.nlm.nih.gov/34235748","citation_count":0,"is_preprint":false},{"pmid":"41832516","id":"PMC_41832516","title":"Oncogenic SOX9-TRAIP signaling drives gastric cancer progression by mediating the degradation of the CPEB3-mTORC1 tumor suppressor axis.","date":"2026","source":"World journal of surgical oncology","url":"https://pubmed.ncbi.nlm.nih.gov/41832516","citation_count":0,"is_preprint":false},{"pmid":null,"id":"bio_10.1101_2024.11.30.626186","title":"TTF2 promotes replisome eviction from stalled forks in mitosis","date":"2024-11-30","source":"bioRxiv","url":"https://doi.org/10.1101/2024.11.30.626186","citation_count":0,"is_preprint":true},{"pmid":null,"id":"bio_10.1101_2024.12.01.626218","title":"TTF2 drives mitotic replisome disassembly and MiDAS by coupling the TRAIP ubiquitin ligase to Polε","date":"2024-12-02","source":"bioRxiv","url":"https://doi.org/10.1101/2024.12.01.626218","citation_count":0,"is_preprint":true},{"pmid":null,"id":"bio_10.1101_2024.09.03.610971","title":"USP37 protects mammalian cells during DNA replication stress by counteracting CUL2  <sup>LRR1</sup>  and TRAIP","date":"2024-09-03","source":"bioRxiv","url":"https://doi.org/10.1101/2024.09.03.610971","citation_count":0,"is_preprint":true}],"cost":{"stage1":{"model":"claude-sonnet-4-6","input_tokens":19488,"output_tokens":6951,"usd":0.081365,"stage1_stop_reason":"end_turn"},"stage2":{"model":"claude-opus-4-8","input_tokens":16114,"output_tokens":4819,"usd":0.100523,"stage2_stop_reason":"end_turn"},"total_usd":0.181888,"stage1_batch_id":"msgbatch_017qqVz33Ga63SCDwzb35XPb","stage2_batch_id":"msgbatch_01Scr2Ei9x4HJMiRGxwrmvLK","note":"batch pricing = 50% of standard"},"stage1_raw":"```json\n{\n  \"discoveries\": [\n    {\n      \"year\": 2019,\n      \"finding\": \"TRAIP is an E3 ubiquitin ligase that ubiquitylates the CMG replicative helicase (CDC45-MCM2-7-GINS) when two replisomes converge at a DNA interstrand crosslink (ICL). Short ubiquitin chains on CMG recruit NEIL3 glycosylase (which can directly cleave the crosslink), whereas longer ubiquitin chains trigger CMG unloading by the p97 ATPase, enabling the Fanconi anaemia pathway. TRAIP thereby controls the choice between the two known pathways of replication-coupled ICL repair.\",\n      \"method\": \"Xenopus egg extract reconstitution; biochemical fractionation; ubiquitin chain-length analysis; NEIL3 binding assays; p97 inhibition; epistasis with Fanconi anaemia pathway mutants\",\n      \"journal\": \"Nature\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1 / Strong — reconstituted in vitro in Xenopus extracts with multiple orthogonal methods (ubiquitylation assays, binding assays, p97 inhibition, pathway epistasis), single rigorous study with comprehensive mechanistic dissection\",\n      \"pmids\": [\"30842657\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2019,\n      \"finding\": \"TRAIP ubiquitin ligase drives replisome disassembly in response to incomplete DNA replication in mitosis (mitotic replisome disassembly), providing access to replication forks for other factors; TRAIP is also essential for mitotic DNA repair synthesis (MiDAS) in human cells, and its loss causes mitotic segregation errors.\",\n      \"method\": \"C. elegans embryo genetics; human cell knockdown; epistasis analysis; live imaging of chromosome segregation errors\",\n      \"journal\": \"eLife\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — clean loss-of-function in two independent model systems (C. elegans and human cells) with defined phenotypic readouts (replisome retention, MiDAS defect, segregation errors)\",\n      \"pmids\": [\"31545170\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2019,\n      \"finding\": \"In Xenopus egg extracts, mitotic replisome disassembly depends on TRAIP-mediated formation of K6- and K63-linked ubiquitin chains on MCM7, followed by p97/VCP-dependent extraction. This pathway does not require SUMO modifications (unlike lower eukaryotes) and can remove all replisomes from mitotic chromatin, including stalled ones.\",\n      \"method\": \"Xenopus egg extract; ubiquitin linkage-specific analysis; p97 inhibition; SUMO pathway manipulation\",\n      \"journal\": \"Life science alliance\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1 / Moderate — in vitro reconstitution in Xenopus extracts with linkage-specific ubiquitin chain analysis and p97 inhibition; single lab but multiple orthogonal methods\",\n      \"pmids\": [\"30979826\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2015,\n      \"finding\": \"TRAIP directly interacts with PCNA via a conserved PIP box motif and localizes to active and stressed replication forks. TRAIP promotes ATR-dependent checkpoint signaling by facilitating RPA-bound single-stranded DNA generation upon replication stress; this requires both E3 ligase activity and the PIP box. Loss of TRAIP leads to chromosomal instability and reduced cell survival after replication stress.\",\n      \"method\": \"Co-immunoprecipitation; PIP box mutagenesis; RPA-ssDNA accumulation assays; ATR signaling readouts (Chk1 phosphorylation); clonogenic survival; chromosomal instability analysis\",\n      \"journal\": \"The Journal of cell biology\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — reciprocal Co-IP, domain mutagenesis, and functional assays with multiple orthogonal readouts in a single rigorous study\",\n      \"pmids\": [\"26711499\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2015,\n      \"finding\": \"TRAIP (encoding an E3 RING ubiquitin ligase) relocalizes to sites of DNA damage during S-phase and is required for optimal phosphorylation of H2AX and RPA2 in response to UV irradiation, as well as for replication fork progression through UV-induced lesions. Mutations in TRAIP cause microcephalic primordial dwarfism.\",\n      \"method\": \"Patient genetic analysis; laser microirradiation/foci formation; H2AX and RPA2 phosphorylation assays; DNA fiber assays for fork progression; siRNA knockdown\",\n      \"journal\": \"Nature genetics\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — multiple orthogonal functional readouts (foci, phosphorylation, fiber assays) combined with human genetics; replicated across patient cells and cell lines\",\n      \"pmids\": [\"26595769\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2016,\n      \"finding\": \"TRAIP is required for recruitment of RAP80 to DNA lesions; TRAIP acts upstream of RAP80 and downstream factors including BRCA1. The N-terminus of TRAIP mediates RAP80 interaction, while the C-terminus of TRAIP mediates localization to DNA damage sites through direct interaction with RNF20-RNF40. TRAIP thereby promotes homologous recombination.\",\n      \"method\": \"Co-immunoprecipitation; domain deletion analysis; laser microirradiation foci recruitment assays; siRNA knockdown; HR reporter assays\",\n      \"journal\": \"Nature communications\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — reciprocal Co-IP, domain mapping, and functional epistasis with multiple orthogonal methods in one study\",\n      \"pmids\": [\"26781088\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2016,\n      \"finding\": \"TRAIP encodes a nucleolar protein that migrates to stalled replication forks by targeting PCNA via an evolutionarily conserved PIP box on its C-terminus. Inactivation of TRAIP or disruption of the TRAIP-PCNA interaction compromises replication fork recovery and progression and causes chromosome instability.\",\n      \"method\": \"GFP-TRAIP live imaging; PIP box mutagenesis; PCNA interaction assays; DNA fiber assays; chromosomal instability analysis\",\n      \"journal\": \"Cell discovery\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — live imaging with PIP box mutagenesis and functional fork assays; single lab, overlapping findings with PMID:26711499\",\n      \"pmids\": [\"27462463\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2021,\n      \"finding\": \"In mouse embryonic stem cells, TRAIP ubiquitin ligase mediates a second (mitotic) pathway of CMG helicase disassembly in addition to the S-phase CUL2LRR1-dependent pathway. Both CUL2LRR1 and TRAIP target CMG for ubiquitylation and p97-dependent disassembly, establishing that metazoan replisome disassembly is controlled by a conserved pair of ubiquitin ligases.\",\n      \"method\": \"Mouse embryonic stem cell genetic knockouts; chromatin fractionation; ubiquitylation assays; cell cycle staging\",\n      \"journal\": \"EMBO reports\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — clean KO in mammalian cells with chromatin fractionation and ubiquitylation readouts; confirmed in mouse ESCs extending findings from Xenopus and C. elegans\",\n      \"pmids\": [\"33590678\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2014,\n      \"finding\": \"TRAIP localizes near mitotic chromosomes and its knockdown decreases early mitosis progression time and increases chromosome alignment defects and lagging chromosomes. TRAIP-depleted cells bypass taxol-induced mitotic arrest and show reduced kinetochore MAD2 levels, indicating that TRAIP E3 ubiquitin ligase activity is required for spindle assembly checkpoint control.\",\n      \"method\": \"RNAi knockdown in HeLa cells; live-cell imaging; flow cytometry; kinetochore immunofluorescence (MAD2); taxol/nocodazole treatment; rescue with wild-type vs. ubiquitin-ligase-dead TRAIP\",\n      \"journal\": \"Journal of cell science\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — clean RNAi knockdown with live imaging, rescue experiments (WT vs. catalytic mutant), and MAD2 kinetochore quantification; single lab\",\n      \"pmids\": [\"25335891\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2016,\n      \"finding\": \"TRAIP is post-translationally modified by SUMOylation at five sites; SUMOylation is required for nuclear retention and protein stability of TRAIP. SUMOylation-deficient TRAIP fails to be retained in the nucleus and exhibits reduced protein stability.\",\n      \"method\": \"SUMOylation site mutagenesis; subcellular fractionation; immunofluorescence; protein stability assays (cycloheximide chase)\",\n      \"journal\": \"Biochemical and biophysical research communications\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — mutagenesis of SUMOylation sites combined with fractionation and stability assays; single lab\",\n      \"pmids\": [\"26820530\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2018,\n      \"finding\": \"PRRRSV non-structural protein 1α (nsp1α) interacts with TRAIP at K205, decreases TRAIP SUMOylation and K48-linked ubiquitination, causing redistribution of TRAIP from nucleus to cytoplasm. Cytoplasmic TRAIP then promotes K48-linked ubiquitination and degradation of TBK1, antagonizing TBK1-IRF3-IFN signaling.\",\n      \"method\": \"Co-immunoprecipitation; site-directed mutagenesis (K205); subcellular fractionation; TBK1 ubiquitination assays; IFN signaling reporter assays\",\n      \"journal\": \"Frontiers in immunology\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 3 / Moderate — Co-IP with mutagenesis and functional ubiquitination assays; single lab, viral context\",\n      \"pmids\": [\"30619364\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2018,\n      \"finding\": \"The TRAIP coiled-coil domain interacts with the TRAF-N domain of TRAF2 (but not TRAF1) to inhibit NF-κB signaling. The coiled-coil domain alters stoichiometry between dimer and trimer in a concentration-dependent manner, and the RING domain induces higher-ordered assembly required for TRAF2 interaction.\",\n      \"method\": \"In vitro binding/biochemical characterization; domain deletion and mutagenesis; size-exclusion chromatography; pull-down assays\",\n      \"journal\": \"International journal of molecular sciences\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 1 / Weak — in vitro reconstitution with domain characterization; single lab, no cellular validation of the NF-κB mechanism\",\n      \"pmids\": [\"30127245\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2018,\n      \"finding\": \"TRAIP nucleolar residence is coupled to active ribosomal DNA transcription: RNA polymerase I inhibition or rDNA damage causes TRAIP to diffuse into the nucleoplasm. PCNA binding is dispensable for nucleolus-to-nucleoplasm shuttling after UV. Pre-treatment with DNase/RNase releases TRAIP from nucleoli, suggesting sequestration via nucleic acid structures.\",\n      \"method\": \"RNA polymerase I inhibition (CX-5461); I-PpoI-induced rDNA damage; DNase/RNase pre-treatment; live-cell imaging; PCNA PIP-box mutant analysis; ATM/ATR inhibition\",\n      \"journal\": \"Nucleic acids research\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — multiple perturbation approaches (chemical, enzymatic, genetic) with live imaging; single lab\",\n      \"pmids\": [\"30165463\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2015,\n      \"finding\": \"TRAIP forms homodimers through its coiled-coil (CC) domain; expression of a CC-domain-deleted mutant that cannot homodimerize increases mitotic index and promotes mitotic progression, indicating that homodimerization is required for proper mitotic regulation.\",\n      \"method\": \"Co-immunoprecipitation with TRAIP deletion mutants; mitotic index measurements; flow cytometry\",\n      \"journal\": \"Biochemical and biophysical research communications\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 3 / Moderate — Co-IP domain mapping with functional mitotic readout; single lab\",\n      \"pmids\": [\"26093298\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2019,\n      \"finding\": \"TRAIP promotes ionizing radiation-induced H2B monoubiquitination at K120; deletion of the RING domain or C-terminus of TRAIP abolishes this activity, establishing a role for TRAIP in regulating this histone mark in the DNA damage response.\",\n      \"method\": \"siRNA knockdown; TRAIP deletion mutants; Western blot for H2B-K120 ubiquitination after IR\",\n      \"journal\": \"Oncology reports\",\n      \"confidence\": \"Low\",\n      \"confidence_rationale\": \"Tier 3 / Weak — single lab, single method (Western blot with deletion mutants); no direct ubiquitination reconstitution\",\n      \"pmids\": [\"30942468\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2023,\n      \"finding\": \"TRAIP resolves replication-transcription conflicts specifically during S-phase; rapid TRAIP degradation in S-phase causes DNA damage at transcription start sites, G2 arrest, and cellular senescence. TRAIP's S-phase function in preventing replication-transcription conflicts is essential for cell proliferation.\",\n      \"method\": \"Auxin-induced degron system for rapid TRAIP degradation; cell cycle-specific depletion; γH2AX foci at transcription start sites; cell cycle analysis; senescence assays\",\n      \"journal\": \"Nature communications\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — auxin-induced degron for acute cell-cycle-specific depletion with multiple orthogonal readouts (DNA damage markers, cell cycle, senescence); single lab but rigorous system\",\n      \"pmids\": [\"37604812\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2021,\n      \"finding\": \"TRAIP promotes KANK1 polyubiquitination and subsequent proteasomal degradation, which downregulates IGFBP3 and activates AKT signaling in osteosarcoma cells.\",\n      \"method\": \"Co-immunoprecipitation; ubiquitination assays; Western blot for KANK1, IGFBP3, and AKT pathway; siRNA knockdown and overexpression\",\n      \"journal\": \"Cell death & disease\",\n      \"confidence\": \"Low\",\n      \"confidence_rationale\": \"Tier 3 / Weak — Co-IP and ubiquitination assay in cancer cell lines; single lab, no in vitro reconstitution\",\n      \"pmids\": [\"34349117\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2023,\n      \"finding\": \"TRAIP directly interacts with MYC and promotes K48-linked polyubiquitination at MYC K428 and K430, leading to proteasome-dependent MYC degradation and suppression of MYC transcriptional activity in bladder cancer cells. MYC in turn binds the TRAIP promoter, establishing a negative feedback loop.\",\n      \"method\": \"Co-immunoprecipitation; ubiquitination assays with K428/K430 mutagenesis; proteasome inhibition; MYC transcriptional activity reporter; ChIP for MYC at TRAIP promoter; rescue experiments\",\n      \"journal\": \"Oncogene\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — site-specific ubiquitination mutagenesis combined with ChIP and rescue experiments; single lab\",\n      \"pmids\": [\"38123820\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2023,\n      \"finding\": \"ZNF212 is a direct binding partner of TRAIP; mutual recruitment of TRAIP and ZNF212 to DNA damage sites is interdependent. ZNF212 depletion causes DDR and HR repair defects epistatic to TRAIP. In mESCs, Zfp212 acts upstream of both the NEIL3 and Fanconi anaemia ICL repair pathways. ZNF212 also directly interacts with NEIL3 and promotes its recruitment to ICL lesions.\",\n      \"method\": \"Co-immunoprecipitation (direct interaction); laser microirradiation foci recruitment; epistasis analysis in mESCs; ICL repair assays; NEIL3 recruitment assays\",\n      \"journal\": \"Nucleic acids research\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — reciprocal Co-IP with foci recruitment and genetic epistasis in two cell systems; single lab\",\n      \"pmids\": [\"36594163\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2025,\n      \"finding\": \"CDK phosphorylation of TRAIP in mitosis is essential for mitotic replisome unloading and MiDAS. TRAIP interacts with terminated replisomes in S-phase without ubiquitylating them; CDK phosphorylation specifically activates TRAIP's autoubiquitylation and ubiquitylation of replisomes isolated from mitotic chromatin. CDK-driven phosphorylation alone is not sufficient to activate replisome unloading during S-phase.\",\n      \"method\": \"Auxin-induced degron; CDK inhibition; phospho-mimetic/non-phosphorylatable TRAIP mutants; in vitro ubiquitylation assays with mitotic chromatin; MiDAS assays in human cells\",\n      \"journal\": \"Nucleic acids research\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1-2 / Moderate — in vitro ubiquitylation reconstitution with phospho-mutants combined with cell-based functional assays (MiDAS); single lab with multiple orthogonal methods\",\n      \"pmids\": [\"40637231\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2025,\n      \"finding\": \"USP37 deubiquitylase binds CMG helicase (via CDC45 contact) and counteracts TRAIP-dependent CMG ubiquitylation and premature replisome disassembly. In Xenopus extracts depleted of USP37, TRAIP promotes premature CMG ubiquitylation and disassembly when converging replisomes stall. TRAIP loss suppresses the hypersensitivity of USP37 knockout cells to topoisomerase inhibitors.\",\n      \"method\": \"Xenopus egg extract depletion; Usp37 knockout cells; genetic epistasis (TRAIP mutation suppressing USP37 KO phenotype); CMG ubiquitylation assays; structure-guided CDC45-binding mutations\",\n      \"journal\": \"Nature communications\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1-2 / Strong — Xenopus reconstitution combined with mammalian KO genetics and epistasis; replicated across two independent studies (PMID:40533495 and PMID:40411782)\",\n      \"pmids\": [\"40533495\", \"40411782\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2024,\n      \"finding\": \"TRAIP phosphorylation by mitotic Cyclin B-CDK1 enables formation of a complex with TTF2 (a SWI/SNF ATPase) and DNA polymerase ε. TTF2 tethers TRAIP to replisomes via an N-terminal zinc finger that binds phosphorylated TRAIP and an adjacent peptide that contacts the CMG-associated leading strand DNA polymerase ε (Pol2/POLE2). This TRAIP-TTF2-Pol ε bridge is essential for CMG unloading and stalled fork breakage in mitosis, independently of TTF2 ATPase activity.\",\n      \"method\": \"Xenopus egg extract; AlphaFold-Multimer-guided mutagenesis; biochemical reconstitution; TTF2 zinc finger binding assays; CDK1 phosphorylation of TRAIP; CMG unloading assays; MiDAS assays\",\n      \"journal\": \"bioRxiv\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1-2 / Strong — structure-guided mutagenesis combined with Xenopus reconstitution; replicated in two independent preprint studies (bio_10.1101_2024.11.30.626186 and bio_10.1101_2024.12.01.626218)\",\n      \"pmids\": [\"bio_10.1101_2024.11.30.626186\", \"bio_10.1101_2024.12.01.626218\"],\n      \"is_preprint\": true\n    },\n    {\n      \"year\": 2025,\n      \"finding\": \"TRAIP depletion causes retention of PCNA on chromatin during mitosis; TRAIP-depleted cells entering G1 with chromatin-bound PCNA display reduced Cdt1 levels and impaired S-phase entry, and show delayed S-phase progression. TRAIP functions independently of ATAD5-RFC in PCNA unloading from chromatin.\",\n      \"method\": \"Auxin-induced degron for TRAIP depletion; chromatin fractionation; PCNA immunofluorescence; Cdt1 Western blot; S-phase entry assays; comparison with ATAD5-RFC-depleted cells\",\n      \"journal\": \"Genes to cells\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Weak — clean auxin degron with fractionation and functional readouts; single lab, single study\",\n      \"pmids\": [\"39956965\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2021,\n      \"finding\": \"In vitro, the TRAIP coiled-coil domain (residues 64-166) specifically forms a complex with the RAP80 zinc finger motif (residues 490-584); larger TRAIP fragments (CCLZ or RINGCC) fail to interact with the RAP80 zinc finger under the same conditions.\",\n      \"method\": \"In vitro protein-protein interaction assay; SDS-PAGE; co-elution\",\n      \"journal\": \"Saudi journal of biological sciences\",\n      \"confidence\": \"Low\",\n      \"confidence_rationale\": \"Tier 3 / Weak — single in vitro binding assay; single lab, no cellular validation of the specific domain interaction\",\n      \"pmids\": [\"34867056\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2026,\n      \"finding\": \"TRAIP functions as an E3 ubiquitin ligase that mediates K48-linked polyubiquitination and proteasomal degradation of PLSCR4 in breast cancer cells.\",\n      \"method\": \"Co-immunoprecipitation; K48-linked ubiquitination assays; rescue experiments with PLSCR4 knockdown\",\n      \"journal\": \"Journal of biochemical and molecular toxicology\",\n      \"confidence\": \"Low\",\n      \"confidence_rationale\": \"Tier 3 / Weak — single lab, Co-IP and ubiquitination assay in cancer cell lines without in vitro reconstitution\",\n      \"pmids\": [\"41942828\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2026,\n      \"finding\": \"SOX9 transcription factor directly binds the TRAIP promoter to drive its transcriptional upregulation. TRAIP then acts as the specific E3 ligase for CPEB3, mediating its poly-ubiquitylation and proteasomal degradation, which relieves CPEB3-mediated translational repression and hyperactivates mTORC1 signaling in gastric cancer cells.\",\n      \"method\": \"ChIP for SOX9 at TRAIP promoter; luciferase reporter assay; Co-immunoprecipitation; ubiquitylation assays; epistatic rescue experiments\",\n      \"journal\": \"World journal of surgical oncology\",\n      \"confidence\": \"Low\",\n      \"confidence_rationale\": \"Tier 3 / Weak — single lab, Co-IP and ubiquitination assay in cancer cell lines without in vitro reconstitution of direct ubiquitylation\",\n      \"pmids\": [\"41832516\"],\n      \"is_preprint\": false\n    }\n  ],\n  \"current_model\": \"TRAIP is a replisome-associated RING-domain E3 ubiquitin ligase that ubiquitylates the CMG replicative helicase (CDC45-MCM2-7-GINS) and interacts with PCNA via a conserved PIP box: during S-phase it promotes ATR-dependent checkpoint signaling, resolves replication-transcription conflicts, and — when two forks converge at a DNA interstrand crosslink — generates short ubiquitin chains that recruit NEIL3 glycosylase (prioritizing direct crosslink unhooking) or longer chains that recruit p97/VCP to unload CMG and enable the Fanconi anaemia pathway; in mitosis, CDK1-dependent phosphorylation activates TRAIP by enabling it to form a complex with TTF2 and DNA polymerase ε, which tethers TRAIP to stalled replisomes and drives CMG ubiquitylation (K6/K63-linked on MCM7) and p97-dependent disassembly of all residual replisomes, thereby facilitating MiDAS and preventing segregation errors; TRAIP activity is counterbalanced by the USP37 deubiquitylase that removes untimely CMG ubiquitylation; additionally, TRAIP is SUMOylated (required for nuclear localization and stability), homodimerizes via its coiled-coil domain, recruits RAP80/BRCA1 to lesions via an interaction with RNF20-RNF40, regulates the spindle assembly checkpoint by maintaining kinetochore MAD2 levels, and ubiquitylates non-replisome substrates such as MYC and KANK1 in specific cellular contexts.\"\n}\n```","stage2_raw":"{\n  \"mechanistic_narrative\": \"TRAIP is a RING-domain E3 ubiquitin ligase that operates at the DNA replication machinery to safeguard genome integrity during S-phase and mitosis [#0, #3]. It localizes to active and stressed replication forks through a conserved PIP-box interaction with PCNA, where it promotes ATR-dependent checkpoint signaling and replication fork progression through DNA lesions; loss of TRAIP causes chromosomal instability, and biallelic mutations cause microcephalic primordial dwarfism [#3, #4]. At the heart of its activity, TRAIP ubiquitylates the CMG replicative helicase (CDC45-MCM2-7-GINS): when two forks converge at an interstrand crosslink, short ubiquitin chains recruit NEIL3 glycosylase to unhook the crosslink directly while longer chains trigger p97/VCP-dependent CMG unloading to license the Fanconi anaemia pathway, making TRAIP the switch between the two ICL repair routes [#0]. In mitosis, TRAIP drives disassembly of all residual replisomes — including stalled ones — via K6/K63-linked ubiquitylation of MCM7 and p97-dependent extraction, an activity essential for mitotic DNA synthesis (MiDAS) and accurate chromosome segregation [#1, #2]. This mitotic activity is gated by Cyclin B-CDK1 phosphorylation, which licenses TRAIP autoubiquitylation and CMG ubiquitylation that it cannot perform on terminated replisomes in S-phase [#19]; the opposing USP37 deubiquitylase removes untimely CMG ubiquitylation to prevent premature replisome disassembly [#20]. TRAIP additionally resolves replication-transcription conflicts during S-phase, an activity required for continued proliferation [#15], and it recruits RAP80/BRCA1 to lesions via RNF20-RNF40 to promote homologous recombination [#5]. TRAIP is itself regulated by SUMOylation, which sustains its nuclear retention and stability [#9], and homodimerizes through its coiled-coil domain to control mitotic progression [#13]. Beyond the replisome, TRAIP ubiquitylates context-specific substrates including MYC and KANK1 [#17, #16].\",\n  \"teleology\": [\n    {\n      \"year\": 2014,\n      \"claim\": \"Established the first cellular role for TRAIP's catalytic activity by showing it is required for spindle assembly checkpoint integrity, linking the ligase to faithful mitosis.\",\n      \"evidence\": \"RNAi knockdown in HeLa cells with live imaging, kinetochore MAD2 quantification, and WT-versus-catalytic-dead rescue\",\n      \"pmids\": [\"25335891\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"No direct ubiquitylation substrate identified at the kinetochore\", \"Mechanism by which TRAIP maintains MAD2 levels unresolved\", \"Single-lab observation\"]\n    },\n    {\n      \"year\": 2015,\n      \"claim\": \"Tied TRAIP physically and functionally to the replisome by identifying a PCNA-binding PIP box and a requirement for both ligase activity and PCNA binding in ATR checkpoint signaling, defining TRAIP as a replication-stress factor.\",\n      \"evidence\": \"Reciprocal Co-IP, PIP-box mutagenesis, RPA-ssDNA and Chk1 phosphorylation readouts, clonogenic survival in human cells\",\n      \"pmids\": [\"26711499\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Direct ubiquitylation substrate during replication stress not yet defined\", \"How PIP-box binding couples to ATR activation mechanistically unclear\"]\n    },\n    {\n      \"year\": 2015,\n      \"claim\": \"Connected TRAIP to human disease and to lesion bypass, showing it relocalizes to damage in S-phase, supports H2AX/RPA2 phosphorylation and fork progression, and that mutations cause microcephalic primordial dwarfism.\",\n      \"evidence\": \"Patient genetics, laser microirradiation foci, phosphorylation assays, DNA fiber assays, siRNA\",\n      \"pmids\": [\"26595769\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Causal substrate linking TRAIP to the phosphorylation events not identified\", \"Mechanism linking molecular defect to dwarfism phenotype unresolved\"]\n    },\n    {\n      \"year\": 2016,\n      \"claim\": \"Placed TRAIP upstream in homologous recombination by mapping an N-terminal RAP80 interaction and a C-terminal RNF20-RNF40 interaction that recruits TRAIP to damage and feeds the RAP80/BRCA1 axis.\",\n      \"evidence\": \"Co-IP, domain deletion, laser microirradiation recruitment, HR reporter assays\",\n      \"pmids\": [\"26781088\", \"27462463\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Whether RAP80/BRCA1 recruitment depends on TRAIP catalytic activity not fully resolved\", \"Relationship between this HR role and the fork-protection role unclear\"]\n    },\n    {\n      \"year\": 2016,\n      \"claim\": \"Identified post-translational and structural controls on TRAIP itself — SUMOylation for nuclear retention/stability and nucleolar residence coupled to active rDNA transcription.\",\n      \"evidence\": \"SUMO-site mutagenesis with fractionation and cycloheximide chase; RNA Pol I inhibition, rDNA damage, and DNase/RNase release with live imaging\",\n      \"pmids\": [\"26820530\", \"30165463\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"SUMO E3 ligase responsible for TRAIP modification unknown\", \"Functional purpose of nucleolar sequestration not established\"]\n    },\n    {\n      \"year\": 2019,\n      \"claim\": \"Defined TRAIP's central biochemical activity: ubiquitylation of the CMG helicase at converged forks, with chain length dictating the choice between NEIL3-mediated crosslink unhooking and p97-dependent CMG unloading into the Fanconi anaemia pathway.\",\n      \"evidence\": \"Xenopus egg extract reconstitution with chain-length analysis, NEIL3 binding, p97 inhibition, and Fanconi pathway epistasis\",\n      \"pmids\": [\"30842657\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"How chain length is enzymatically tuned in vivo unclear\", \"Reader specificity distinguishing short versus long chains not fully defined\"]\n    },\n    {\n      \"year\": 2019,\n      \"claim\": \"Generalized TRAIP to a dedicated mitotic replisome-disassembly factor, showing it removes residual/stalled replisomes via K6/K63 chains on MCM7 and p97, and is essential for MiDAS and accurate segregation.\",\n      \"evidence\": \"C. elegans and human cell loss-of-function, Xenopus extract with linkage-specific ubiquitin analysis and p97 inhibition, live imaging of segregation errors\",\n      \"pmids\": [\"31545170\", \"30979826\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Mechanism restricting this activity to mitosis not addressed in these studies\", \"How K6/K63 chains are specified at MCM7 unknown\"]\n    },\n    {\n      \"year\": 2021,\n      \"claim\": \"Positioned TRAIP within the broader replisome-disassembly framework, showing metazoans use a conserved pair of ligases (S-phase CUL2-LRR1 and mitotic TRAIP) for CMG unloading.\",\n      \"evidence\": \"Mouse ESC knockouts with chromatin fractionation, ubiquitylation assays, and cell-cycle staging\",\n      \"pmids\": [\"33590678\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Division of labor between the two ligases under different stress contexts not fully mapped\"]\n    },\n    {\n      \"year\": 2023,\n      \"claim\": \"Established an S-phase-specific function in resolving replication-transcription conflicts essential for proliferation, distinguishing it from TRAIP's mitotic role.\",\n      \"evidence\": \"Auxin-induced degron for cell-cycle-specific depletion, gamma-H2AX at transcription start sites, cell cycle and senescence assays\",\n      \"pmids\": [\"37604812\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Direct substrate at conflict sites not identified\", \"Whether CMG ubiquitylation underlies conflict resolution unclear\"]\n    },\n    {\n      \"year\": 2024,\n      \"claim\": \"Solved how TRAIP is restricted to mitosis, showing CDK1 phosphorylation builds a TRAIP-TTF2-Pol epsilon bridge that tethers TRAIP to replisomes to drive CMG unloading and fork breakage.\",\n      \"evidence\": \"Xenopus extract with AlphaFold-Multimer-guided mutagenesis, TTF2 zinc-finger binding, CDK1 phosphorylation, CMG unloading and MiDAS assays (preprint)\",\n      \"pmids\": [\"bio_10.1101_2024.11.30.626186\", \"bio_10.1101_2024.12.01.626218\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Awaits peer review\", \"How the bridge selectively recognizes stalled versus active replisomes not fully resolved\"]\n    },\n    {\n      \"year\": 2025,\n      \"claim\": \"Refined the cell-cycle gating model: CDK phosphorylation activates TRAIP autoubiquitylation and CMG ubiquitylation, and is necessary but not sufficient — TRAIP binds terminated replisomes in S-phase without ubiquitylating them.\",\n      \"evidence\": \"Auxin degron, CDK inhibition, phospho-mimetic/non-phosphorylatable mutants, in vitro ubiquitylation with mitotic chromatin, MiDAS assays\",\n      \"pmids\": [\"40637231\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"The additional mitotic input beyond CDK phosphorylation not fully defined\", \"Structural basis of activation not resolved\"]\n    },\n    {\n      \"year\": 2025,\n      \"claim\": \"Identified the antagonist that constrains TRAIP timing: USP37 deubiquitylase binds CMG via CDC45 and reverses premature TRAIP-dependent CMG ubiquitylation, with TRAIP loss suppressing USP37-KO topoisomerase-inhibitor sensitivity.\",\n      \"evidence\": \"Xenopus extract depletion, USP37-knockout cells, genetic epistasis, CMG ubiquitylation assays, structure-guided CDC45-binding mutations\",\n      \"pmids\": [\"40533495\", \"40411782\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"How USP37 activity is itself temporally regulated unclear\", \"Whether USP37 acts on mitotic as well as S-phase TRAIP activity not fully delineated\"]\n    },\n    {\n      \"year\": 2023,\n      \"claim\": \"Extended TRAIP function to context-specific substrate ubiquitylation, identifying MYC as a direct K48-ubiquitylation target in a negative feedback loop and KANK1 in osteosarcoma signaling.\",\n      \"evidence\": \"Co-IP, site-specific ubiquitylation mutagenesis, ChIP, proteasome inhibition and rescue in cancer cell lines\",\n      \"pmids\": [\"38123820\", \"34349117\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"No in vitro reconstitution of direct ubiquitylation for KANK1\", \"Relationship between these cancer-context substrates and the core replisome role unclear\"]\n    },\n    {\n      \"year\": null,\n      \"claim\": \"How TRAIP's distinct substrate selectivities (CMG, MYC, KANK1, histone marks) are coordinated and partitioned across S-phase, mitosis, and specific cellular contexts remains unresolved.\",\n      \"evidence\": \"\",\n      \"pmids\": [],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"No unifying determinant of substrate choice identified\", \"Structural basis of the catalytic activation switch not solved\", \"Mechanism connecting molecular defects to the dwarfism phenotype unknown\"]\n    }\n  ],\n  \"mechanism_profile\": {\n    \"molecular_activity\": [\n      {\"term_id\": \"GO:0016740\", \"supporting_discovery_ids\": [0, 2, 3, 17]},\n      {\"term_id\": \"GO:0140096\", \"supporting_discovery_ids\": [0, 2, 17]},\n      {\"term_id\": \"GO:0016874\", \"supporting_discovery_ids\": [0, 5]}\n    ],\n    \"localization\": [\n      {\"term_id\": \"GO:0005634\", \"supporting_discovery_ids\": [9]},\n      {\"term_id\": \"GO:0005730\", \"supporting_discovery_ids\": [6, 12]},\n      {\"term_id\": \"GO:0005694\", \"supporting_discovery_ids\": [1, 2, 22]}\n    ],\n    \"pathway\": [\n      {\"term_id\": \"R-HSA-73894\", \"supporting_discovery_ids\": [0, 4, 5]},\n      {\"term_id\": \"R-HSA-69306\", \"supporting_discovery_ids\": [3, 6, 7]},\n      {\"term_id\": \"R-HSA-1640170\", \"supporting_discovery_ids\": [1, 8, 19]},\n      {\"term_id\": \"R-HSA-392499\", \"supporting_discovery_ids\": [0, 2, 17]}\n    ],\n    \"complexes\": [\"CMG replicative helicase (substrate-bound)\", \"TRAIP-TTF2-DNA polymerase epsilon\"],\n    \"partners\": [\"PCNA\", \"TTF2\", \"USP37\", \"RAP80\", \"RNF20\", \"RNF40\", \"ZNF212\", \"MYC\"],\n    \"other_free_text\": []\n  }\n}","audit_flag":null,"evaluation":{"pairwise":"win","faith_supported":8,"faith_total":8,"faith_pct":100.0}}