{"gene":"RECQL5","run_date":"2026-06-10T06:43:36","timeline":{"discoveries":[{"year":2007,"finding":"RECQL5 binds RAD51 recombinase and inhibits RAD51-mediated D-loop formation; it displaces RAD51 from single-stranded DNA (ssDNA) in a reaction requiring ATP hydrolysis and RPA, thereby disrupting RAD51 presynaptic filaments and suppressing homologous recombination.","method":"Purified protein biochemical assays (D-loop formation assay, ssDNA displacement assay), electron microscopy, ATPase mutant analysis","journal":"Genes & development","confidence":"High","confidence_rationale":"Tier 1 / Strong — in vitro reconstitution with purified proteins, electron microscopy structural validation, ATP hydrolysis mutant controls; replicated in multiple subsequent studies","pmids":["18003859"],"is_preprint":false},{"year":2008,"finding":"RECQL5 (RECQ5) is a bona fide RNA polymerase II (RNAPII)-associated protein; the interaction is direct and mediated by the RPB1 subunit of RNAPII; RECQL5 is the only human RECQ family member that associates with RNAPII.","method":"Chromatin isolation, targeted proteomic analysis, direct interaction assay with purified proteins, co-immunoprecipitation","journal":"Proceedings of the National Academy of Sciences of the United States of America","confidence":"High","confidence_rationale":"Tier 2 / Strong — direct biochemical interaction with purified proteins, chromatin fractionation, confirmed in multiple subsequent studies","pmids":["18562274"],"is_preprint":false},{"year":2000,"finding":"The large isoform RecQ5beta localizes exclusively in the nucleoplasm, while small isoforms RecQ5alpha and RecQ5gamma remain cytoplasmic; RecQ5beta interacts with topoisomerases 3alpha and 3beta but not topoisomerase 1.","method":"Immunocytochemical staining of tagged isoforms expressed in 293EBNA cells, immunoprecipitation","journal":"Nucleic acids research","confidence":"Medium","confidence_rationale":"Tier 3 / Moderate — immunoprecipitation and immunostaining, single lab, two orthogonal methods","pmids":["10710432"],"is_preprint":false},{"year":2005,"finding":"Recql5 and Blm have nonredundant roles in suppressing crossovers (sister chromatid exchange) in mouse cells; deletion of both Blm and Recql5 leads to an even higher SCE frequency than either single knockout, establishing a Recql5-dependent, Blm-independent pathway for suppressing crossovers during mitosis.","method":"Genetic knockout in mouse ES cells and MEFs, sister chromatid exchange assay","journal":"Molecular and cellular biology","confidence":"High","confidence_rationale":"Tier 2 / Strong — genetic epistasis via double knockout, replicated in mouse ES cells and MEFs, confirmed by subsequent studies","pmids":["15831450"],"is_preprint":false},{"year":2009,"finding":"RECQL5 inhibits both initiation and elongation of RNAPII-dependent transcription in vitro; this inhibition requires its RNAPII-interaction domain but not its helicase activity.","method":"In vitro transcription assay reconstituted with purified general transcription factors and RNAPII, RNAPII-interaction-deficient RECQL5 mutant","journal":"The Journal of biological chemistry","confidence":"High","confidence_rationale":"Tier 1 / Moderate — in vitro reconstituted transcription assay with mutagenesis, single lab but multiple orthogonal controls","pmids":["19570979"],"is_preprint":false},{"year":2010,"finding":"RECQL5 specifically binds the Ser2,5-phosphorylated C-terminal repeat domain (CTD) of RPB1 via a Set2-Rpb1-interacting (SRI) motif at its C-terminus; RECQL5 associates with RNAPII-transcribed genes in an SRI-dependent manner, with density correlating with Ser2-CTD phosphorylation marking productive elongation.","method":"Binding assays with CTD phosphorylation variants, chromatin immunoprecipitation (ChIP), SRI deletion/mutation analysis","journal":"Nucleic acids research","confidence":"High","confidence_rationale":"Tier 2 / Moderate — direct binding assay with phosphorylated CTD variants, ChIP in cells with domain mutants, single lab, multiple orthogonal methods","pmids":["20705653"],"is_preprint":false},{"year":2010,"finding":"RECQL5 interacts with RAD51 through a RAD51-interacting domain; RECQL5 mutants that fail to bind RAD51 retain normal ATPase activity but are impaired in displacing RAD51 from ssDNA, and ablation of RECQL5-RAD51 complex formation alleviates RECQL5's inhibitory effect on HR-mediated DSB repair.","method":"Mapping of RAD51-interacting domain, generation of binding-deficient point mutants, in vitro ssDNA displacement assay, HR reporter assay in cells","journal":"The Journal of biological chemistry","confidence":"High","confidence_rationale":"Tier 1 / Moderate — domain mapping with mutagenesis, in vitro displacement assay, cellular HR reporter, single lab, multiple orthogonal methods","pmids":["20348101"],"is_preprint":false},{"year":2010,"finding":"RECQL5 interacts with RNAPII through both KIX (binds initiation form Pol IIa and elongation form Pol IIo) and SRI (binds only elongation form Pol IIo) domains; RECQL5 requires both helicase activity and KIX-mediated Pol II interaction for full suppression of sister chromatid exchange and resistance to camptothecin.","method":"Purification of RECQL5-associated complex, mass spectrometry identification, structural modeling-guided mutagenesis, SCE assay, drug sensitivity assay","journal":"Molecular and cellular biology","confidence":"High","confidence_rationale":"Tier 2 / Moderate — complex purification with MS identification, domain mutagenesis, functional cellular assays, single lab, multiple orthogonal methods","pmids":["20231364"],"is_preprint":false},{"year":2009,"finding":"RECQL5 is constitutively associated with the MRE11-RAD50-NBS1 (MRN) complex through direct interactions with both MRE11 and NBS1; RECQL5 specifically inhibits the 3'→5' exonuclease activity of MRE11; the MRN complex is required for recruitment of RECQL5 to sites of DNA damage.","method":"Purified protein interaction assays, co-immunoprecipitation, exonuclease activity assay, laser-induced damage recruitment (live cell imaging)","journal":"Nucleic acids research","confidence":"High","confidence_rationale":"Tier 2 / Moderate — purified protein interaction, enzymatic assay, live cell imaging, single lab, three orthogonal methods","pmids":["19270065"],"is_preprint":false},{"year":2011,"finding":"RECQL5 physically and functionally interacts with Topoisomerase IIα; RECQL5 stimulates the decatenation activity of Topoisomerase IIα in vitro; RECQL5 co-localizes with Topoisomerase IIα during S-phase; RECQL5 depletion causes G2/M arrest, undercondensed/entangled chromosomes, and phenotypes resembling Topoisomerase II inhibition.","method":"Direct interaction assay with purified proteins, decatenation assay, co-localization (immunofluorescence), stable knockdown cell lines, cell cycle analysis","journal":"Nucleic acids research","confidence":"High","confidence_rationale":"Tier 2 / Moderate — direct biochemical stimulation assay, co-localization, cell phenotype with depletion, single lab, multiple orthogonal methods","pmids":["22013166"],"is_preprint":false},{"year":2011,"finding":"The SRI domain of RECQL5 is important for suppressing spontaneous DSBs and the p53-dependent transcription stress response; in RECQL5-depleted cells, active RNAPII accumulates on chromatin and DNA breaks associate with RNAPII-dependent transcribed loci; transcription inhibition eliminates both RNAPII accumulation and spontaneous DSB formation.","method":"SRI domain mutants, RNAPII ChIP, γH2AX foci analysis, transcription inhibitor treatment, p53 reporter assay","journal":"Molecular and cellular biology","confidence":"High","confidence_rationale":"Tier 2 / Moderate — domain mutagenesis, ChIP, pharmacological epistasis, multiple readouts, single lab","pmids":["21402780"],"is_preprint":false},{"year":2012,"finding":"RECQL5 contains a BRC repeat variant (BRCv) that mediates interaction with RAD51 through two conserved motifs; mutations in either motif compromise RECQL5's ability to associate with RAD51, inhibit D-loop formation, suppress SCE, and confer resistance to camptothecin-induced replication stress.","method":"Identification and mutagenesis of BRCv domain, co-immunoprecipitation, D-loop inhibition assay, SCE assay, drug sensitivity assay","journal":"The Journal of biological chemistry","confidence":"High","confidence_rationale":"Tier 2 / Moderate — domain mapping with mutagenesis, in vitro biochemical assay, multiple cellular readouts, single lab","pmids":["22645136"],"is_preprint":false},{"year":2013,"finding":"Cryo-EM structure of elongating Pol II arrested in complex with RECQL5 shows that RECQL5 helicase domain is positioned to sterically block elongation; RECQL5 KIX domain contacts the Rpb1 jaw domain at a site overlapping the TFIIS binding site; RECQL5 interferes with TFIIS-promoted transcriptional read-through in vitro, representing structural mimicry of the Pol II-TFIIS interaction.","method":"Cryo-EM structure determination, crystal structure of KIX domain, in vitro transcription read-through assay, binding competition assay","journal":"Nature structural & molecular biology","confidence":"High","confidence_rationale":"Tier 1 / Strong — cryo-EM structure plus crystal structure, in vitro functional validation, single lab but multiple orthogonal structural and biochemical methods","pmids":["23748380"],"is_preprint":false},{"year":2013,"finding":"RECQL5 promotes formation of non-crossover products during DSB-induced HR by acting during the post-synaptic phase of synthesis-dependent strand annealing (SDSA); RECQL5 counteracts the inhibitory effect of RAD51 on RAD52-mediated DNA annealing in vitro; RECQL5 deficiency increases RAD51 occupancy at DSB sites and elevates SCE upon inactivation of the Holliday junction dissolution pathway.","method":"HR reporter assay in cells, in vitro annealing assay with purified proteins, ChIP for RAD51 at DSB sites, SCE assay","journal":"Nucleic acids research","confidence":"High","confidence_rationale":"Tier 2 / Moderate — in vitro reconstitution, ChIP, cellular reporter assays, single lab, multiple orthogonal methods","pmids":["24319145"],"is_preprint":false},{"year":2014,"finding":"RECQL5 depletion causes a genome-wide shift in RNAPII density; loss of RECQL5 increases the average rate of RNAPII elongation concurrent with increased stalling, pausing, arrest, and/or backtracking (transcription stress); chromosomal breakpoints in RECQL5-depleted cells overlap with areas of elevated transcription stress.","method":"Genome-wide RNAPII ChIP-seq, chromosomal copy-number analysis, RNA-seq","journal":"Cell","confidence":"High","confidence_rationale":"Tier 2 / Strong — genome-wide ChIP-seq with loss-of-function and gain-of-function experiments, multiple readouts, replicated by independent groups","pmids":["24836610"],"is_preprint":false},{"year":2015,"finding":"RECQL5 promotes SUMOylation of TOP1 at K391 and K436 by facilitating interaction between the PIAS1-SRSF1 E3 ligase complex and TOP1 in chromatin containing active RNAPII; this SUMOylation is necessary for TOP1 binding to RNAPIIo, recruitment of RNA splicing factors to transcribed chromatin, and reduction of R-loops; SUMOylation also negatively regulates TOP1 topoisomerase activity.","method":"In vivo SUMOylation assays, co-immunoprecipitation, ChIP, R-loop detection (S9.6 antibody), mutagenesis of SUMOylation sites","journal":"Nature communications","confidence":"High","confidence_rationale":"Tier 2 / Moderate — multiple orthogonal methods in vivo and in vitro, mutagenesis of SUMOylation sites, single lab","pmids":["25851487"],"is_preprint":false},{"year":2016,"finding":"RECQL5 associates with both RNAPI and RNAPII transcription complexes in DNA replication foci; RECQL5 counteracts replication fork stalling in RNAPI- and RNAPII-transcribed genes; RECQL5-deficient cells accumulate RAD18 foci and BRCA1-dependent RAD51 foci at sites of replication-transcription interference; RECQL5-PCNA interaction promotes RAD18-dependent PCNA ubiquitination and helicase activity promotes processing of replication intermediates.","method":"Co-immunoprecipitation, immunofluorescence, DNA fiber assay, PCNA ubiquitination assay, RECQL5-PCNA interaction domain mapping","journal":"The Journal of cell biology","confidence":"High","confidence_rationale":"Tier 2 / Moderate — multiple biochemical and cell-biological assays, single lab, multiple orthogonal methods","pmids":["27502483"],"is_preprint":false},{"year":2017,"finding":"RECQL5 associates with common fragile sites (CFSs) in early mitosis through physical interaction with MUS81, dependent on CDK1-mediated phosphorylation at Ser727; RECQL5 promotes MUS81-dependent mitotic DNA synthesis; RECQL5 alleviates the inhibitory effect of RAD51 on 3'-flap DNA cleavage by MUS81-EME1 through its RAD51 filament disruption activity; mutation of Ser727 or the RAD51-interacting domain impairs CFS expression and causes defective chromosome segregation.","method":"Co-immunoprecipitation, ChIP at CFS loci, DNA synthesis assay, in vitro cleavage assay with purified proteins, CDK1 phosphorylation assay, phosphorylation-site mutant analysis","journal":"Molecular cell","confidence":"High","confidence_rationale":"Tier 2 / Strong — biochemical reconstitution, phosphorylation site mutagenesis, ChIP, cellular phenotype with multiple mutants, single lab, multiple orthogonal methods","pmids":["28575661"],"is_preprint":false},{"year":2017,"finding":"Crystal structures of the RECQL5 core helicase domain in 'Open' and 'Closed' conformations (with and without ADP) reveal the mechano-chemical cycle; SAXS shows the 'Open' form predominates in solution; structure-guided mutagenesis defines residues important for ATPase, helicase, and DNA binding activities.","method":"X-ray crystallography, small-angle X-ray scattering (SAXS), ATPase assay, helicase assay, mutagenesis","journal":"Nucleic acids research","confidence":"High","confidence_rationale":"Tier 1 / Moderate — crystal structures with SAXS validation and functional mutagenesis, single lab, multiple orthogonal structural and biochemical methods","pmids":["28100692"],"is_preprint":false},{"year":2021,"finding":"Single-molecule imaging shows RECQL5 is an ATP-dependent ssDNA motor protein that translocates on RPA-coated ssDNA and on RAD51-coated ssDNA, readily dismantling RAD51-ssDNA filaments; disruption of the RECQL5-RAD51 protein-protein interface (F666A mutation) reduces translocation velocity ~50%; RECQL5 can remove ATP-hydrolysis-deficient RAD51-K133R and the enhanced-binding RAD51-I287T mutant from ssDNA; RECQL5 cannot dismantle RAD51-bound heteroduplex joint molecules.","method":"Single-molecule TIRF imaging, ensemble kinetic assays, purified protein reconstitution, RECQL5-F666A mutant analysis","journal":"Nucleic acids research","confidence":"High","confidence_rationale":"Tier 1 / Strong — single-molecule imaging plus ensemble assays with reconstituted components and multiple mutants; mechanistic detail on translocation and filament disruption independently validated","pmids":["33332547"],"is_preprint":false},{"year":2021,"finding":"ATRX-dependent HR outcompetes RECQL5-dependent SDSA for repair of most two-ended DSBs; subpathway choice depends on interaction of both ATRX and RECQL5 with PCNA; RECQL5-dependent SDSA prevents CO formation as assessed by SCE measurements.","method":"HR subpathway reporter assays, SCE assay, PCNA interaction domain analysis, genetic epistasis with ATRX/RECQL5/MUS81/GEN1 knockouts","journal":"Proceedings of the National Academy of Sciences of the United States of America","confidence":"High","confidence_rationale":"Tier 2 / Moderate — epistasis analysis with multiple knockouts, PCNA interaction domain requirement, SCE assay, single lab, multiple orthogonal methods","pmids":["33431668"],"is_preprint":false},{"year":2012,"finding":"Both the helicase and KIX domains of RECQL5 are required for its recruitment to DSBs; the MRN complex recruits RECQL5 to DSBs independently of its exonuclease activity; RECQL5 recruitment is also independent of transcription by RNAPII, of BLM, WRN, and ATM.","method":"Live cell confocal imaging with domain deletion mutants, laser-induced DSB recruitment assay, co-depletion experiments","journal":"DNA repair","confidence":"Medium","confidence_rationale":"Tier 3 / Moderate — live cell imaging with domain mutants and genetic controls, single lab","pmids":["22633600"],"is_preprint":false},{"year":2012,"finding":"RECQL5 interacts physically and functionally with WRN helicase; RECQL5 co-operates with WRN on stalled replication fork-like structures and stimulates WRN helicase activity on DNA fork duplexes; both proteins re-localize from nucleolus to nucleus after replicative stress; RECQL5 is essential for cell survival in the absence of WRN (synthetic lethality).","method":"Co-immunoprecipitation, in vitro helicase stimulation assay, immunofluorescence co-localization, double knockout cell viability assay","journal":"Nucleic acids research","confidence":"High","confidence_rationale":"Tier 2 / Moderate — in vitro helicase stimulation with purified proteins, co-IP, cellular co-localization, genetic synthetic lethality, single lab, multiple orthogonal methods","pmids":["23180761","28180303"],"is_preprint":false},{"year":2012,"finding":"RECQL5 depletion causes sensitivity to oxidative stress, accumulation of endogenous DNA damage, increased poly(ADP-ribosyl)ation response, and accumulation at laser-induced single-strand breaks (not DSBs); RECQL5 depletion affects PARP-1 and XRCC1 protein levels, suggesting RECQL5 participates in base excision repair.","method":"Laser microirradiation (SSB vs DSB), comet assay, immunofluorescence, western blot for PARP-1 and XRCC1, siRNA knockdown","journal":"Molecular biology of the cell","confidence":"Medium","confidence_rationale":"Tier 3 / Moderate — multiple cellular assays, live cell imaging, single lab","pmids":["22973052"],"is_preprint":false},{"year":2010,"finding":"RECQL5 is identified within a super complex containing SWI/SNF chromatin remodeling complex and RNAPII core complex; RECQL5 is detected in the RNAPII holoenzyme but not purified RNAPII core complex.","method":"Biochemical purification of complex, co-immunoprecipitation, mass spectrometry","journal":"International journal of biochemistry and molecular biology","confidence":"Medium","confidence_rationale":"Tier 3 / Weak — single co-purification/co-IP approach, single lab","pmids":["21968968"],"is_preprint":false},{"year":2015,"finding":"PARP1 and PAR (poly(ADP-ribose)) regulate RECQL5 activity and recruitment to laser-induced DNA damage; PARylation is involved in recruitment of RECQL5 to damage sites; RECQL5 interacts noncovalently with PAR; PARP inhibition causes increased sensitivity in RECQL5-depleted cells.","method":"Laser microirradiation recruitment assay, in vitro PAR-binding assay, co-immunoprecipitation with PARP1, PARP inhibitor sensitivity assay","journal":"Molecular and cellular biology","confidence":"Medium","confidence_rationale":"Tier 2 / Weak — direct PAR-binding assay and recruitment imaging, single lab, limited mechanistic depth","pmids":["26391948"],"is_preprint":false},{"year":2015,"finding":"RECQL5 possesses relatively strong strand annealing activity on long and short duplexed substrates compared to other RecQ helicases; unlike other RecQs, its annealing activity is not inhibited by ATP; RECQL5 efficiently catalyzes RNA-to-DNA annealing in vitro in presence or absence of ATP.","method":"In vitro strand annealing assays with purified proteins, comparison across all five human RecQ helicases, ATP titration","journal":"DNA repair","confidence":"Medium","confidence_rationale":"Tier 1 / Weak — in vitro biochemical assay with purified proteins, single lab","pmids":["26717024"],"is_preprint":false},{"year":2016,"finding":"RECQL5 can unfold G-quadruplex (GQ) DNA structures in a single-molecule assay, but with ~10-fold weaker activity than BLM and WRN; RECQL5 demonstrates ssDNA reeling activity comparable to BLM; GQ unfolding and ssDNA reeling activities are not coupled for RECQL5.","method":"Single-molecule FRET imaging, multiple GQ substrates, ATP concentration titration","journal":"Biophysical journal","confidence":"Medium","confidence_rationale":"Tier 1 / Weak — single-molecule assay with purified protein, single lab","pmids":["27332117"],"is_preprint":false},{"year":2020,"finding":"An alternative splicing isoform of RECQL5 (RECQL5β1) containing 17 extra amino acids in the KIX domain has markedly decreased binding affinity to RNAPII, weaker transcription elongation repression activity, but stronger binding to MRE11 and enhanced DSB repair activity compared to canonical RECQL5β.","method":"Isoform identification, binding affinity assay, in vitro transcription assay, co-immunoprecipitation with MRE11, DNA repair assay in rescue cells","journal":"DNA repair","confidence":"Medium","confidence_rationale":"Tier 2 / Weak — binding and functional assays with isoform comparison, single lab","pmids":["33197722"],"is_preprint":false},{"year":2025,"finding":"Cryo-EM structures of stalled human Pol II elongation complexes bound to RECQL5 reveal that RECQL5 contacts the Rpb1 jaw domain acting as a transcriptional roadblock; in its nucleotide-free state RECQL5 twists the downstream DNA in the elongation complex; upon nucleotide binding, RECQL5 undergoes a conformational change that allosterically induces Pol II toward a post-translocation state.","method":"Cryo-electron microscopy structure determination of Pol II EC-RECQL5 complexes, in vitro transcription assays","journal":"Nature structural & molecular biology","confidence":"High","confidence_rationale":"Tier 1 / Moderate — cryo-EM structures with functional biochemical validation, peer-reviewed publication","pmids":["40624164"],"is_preprint":false},{"year":2025,"finding":"Cryo-EM structures of RECQL5 bound to multiple Pol II elongation complexes reveal an α-helix of RECQL5 ('brake helix') responsible for binding Pol II and slowing transcription elongation; the transcription-coupled DNA repair (TCR) complex allows Pol II to overcome RECQL5-induced braking through concerted translocase activity and competition with RECQL5 for Pol II engagement; RECQL5 inhibits TCR-mediated Pol II ubiquitination to prevent activation of DNA repair pathway.","method":"Cryo-EM structure determination, biochemical transcription elongation assay, RECQL5 deletion/mutation analysis, TCR complex competition assay, Pol II ubiquitination assay","journal":"Nature structural & molecular biology","confidence":"High","confidence_rationale":"Tier 1 / Moderate — cryo-EM structures with functional biochemical validation of multiple mechanisms, peer-reviewed publication","pmids":["40624163"],"is_preprint":false},{"year":2025,"finding":"RECQL5 localizes to the dense fibrillar component of the nucleolus, associates with pre-rRNA processing factors, recognizes pre-rRNA, and can unwind double-stranded RNA in vitro; loss of RECQL5 causes accumulation of 47S, 30SL5', and 30S pre-rRNA and reduction of 21S pre-rRNA, indicating a role in pre-rRNA processing; loss of RECQL5 causes unprocessed pre-rRNA to hybridize with rDNA, triggering R-loop formation and ATR activation.","method":"Immunofluorescence/co-localization, co-immunoprecipitation with pre-rRNA processing factors, in vitro dsRNA unwinding assay, Northern blot for pre-rRNA intermediates, R-loop detection (S9.6), ATR activation assay","journal":"Nucleic acids research","confidence":"High","confidence_rationale":"Tier 2 / Moderate — in vitro RNA unwinding assay, Northern blot for specific pre-rRNA species, R-loop and ATR assays, co-IP with processing factors, single lab, multiple orthogonal methods","pmids":["40823811"],"is_preprint":false},{"year":2025,"finding":"RECQL5 localizes to stalled replication fork sites and restricts RAD51-mediated excessive fork reversal to promote unrestrained DNA synthesis; this function requires RECQL5 binding to PCNA, RAD51, and helicase activity but is independent of its RNAPII interaction; notably, the RECQL5 mutant lacking RAD51 interaction still regulates transcription elongation comparably to wild-type, demonstrating that fork reversal regulation and transcription elongation regulation are molecularly distinct functions.","method":"DNA fiber assay, proximity ligation assay at forks, co-depletion epistasis with SMARCAL1/ZRANB3/HLTF/FBH1, HR-defective RAD51 mutant rescue, PCNA-interaction and RNAPII-interaction domain mutants","journal":"Nucleic acids research","confidence":"High","confidence_rationale":"Tier 2 / Moderate — multiple domain mutants, genetic epistasis with fork remodelers, fiber assay, single lab, multiple orthogonal methods","pmids":["41099703"],"is_preprint":false},{"year":2025,"finding":"RECQL5 uses a 'brake helix' as a doorstop to control RNAPII translocation along DNA at the atomic level; at the mesoscale level RECQL5 forms a condensate scaffold matrix integrating phosphorylated RNAPII elongation complex through site-specific interactions.","method":"Cryo-EM, cryo-electron tomography, coarse-grained molecular simulations, biochemical reconstitution","journal":"bioRxiv","confidence":"Medium","confidence_rationale":"Tier 1 / Weak — structural and simulation data from preprint, not yet peer-reviewed","pmids":["bio_10.1101_2025.02.05.636647"],"is_preprint":true},{"year":2024,"finding":"IWS1 protects the activated transcription elongation complex from RECQL5 inhibition by binding the RPB1 jaw domain competitively with RECQL5, both of which share this binding site.","method":"Cryo-EM structure of elongation complexes, binding competition assay, functional transcription assay","journal":"bioRxiv","confidence":"Medium","confidence_rationale":"Tier 1 / Weak — cryo-EM and functional assay from preprint, finding about RECQL5 is ancillary to main IWS1 paper","pmids":["bio_10.1101_2025.08.28.672863"],"is_preprint":true},{"year":2008,"finding":"Deletion of Recql5 in mice results in cancer susceptibility; Recql5-deficient cells exhibit elevated frequencies of spontaneous DNA double-strand breaks and HR events, and are prone to gross chromosomal rearrangements under replication stress.","method":"Mouse knockout, tumor incidence analysis, HR reporter assay, chromosomal rearrangement assay","journal":"Genes & development","confidence":"High","confidence_rationale":"Tier 2 / Strong — knockout mouse model with multiple cellular readouts, replicated by subsequent studies","pmids":["18003859"],"is_preprint":false}],"current_model":"RECQL5 is a multifunctional RecQ DNA helicase that safeguards genome stability through at least three mechanistically distinct activities: (1) it disrupts RAD51 presynaptic filaments on ssDNA in an ATP hydrolysis- and RPA-dependent manner via a BRC-repeat variant (BRCv) domain, suppressing inappropriate homologous recombination and promoting SDSA over crossover-prone pathways; (2) it binds the phosphorylated CTD of elongating RNA Polymerase II via SRI and KIX domains, acts as a transcriptional roadblock that slows Pol II elongation and controls RNAPII translocation state as revealed by cryo-EM, thereby preventing transcription stress and transcription-replication conflicts; and (3) it cooperates with MUS81-EME1 endonuclease at common fragile sites during mitosis, requires CDK1-dependent phosphorylation (Ser727), stimulates Topoisomerase IIα decatenation activity, facilitates pre-rRNA processing in the nucleolus, and interacts with the MRN complex for recruitment to DNA double-strand breaks, collectively positioning RECQL5 as a critical coordinator at the intersection of DNA replication, repair, and transcription."},"narrative":{"mechanistic_narrative":"RECQL5 is a multifunctional RecQ-family DNA helicase that safeguards genome stability at the interface of DNA replication, repair, and transcription, and its loss in mice causes cancer susceptibility together with spontaneous DSBs, elevated homologous recombination, and replication-stress-induced chromosomal rearrangements [PMID:18003859]. In recombination, RECQL5 binds RAD51 and disrupts RAD51 presynaptic filaments on ssDNA in an ATP-hydrolysis- and RPA-dependent manner, inhibiting D-loop formation and suppressing inappropriate recombination [PMID:18003859]; single-molecule imaging established it as an ATP-dependent ssDNA translocase that actively dismantles RAD51 filaments, with translocation enhanced by a direct RECQL5-RAD51 interface [PMID:33332547]. This RAD51-interaction is mediated by a BRC-repeat-variant (BRCv) domain whose mutation impairs filament disruption, SCE suppression, and camptothecin resistance [PMID:20348101, PMID:22645136], and functionally channels DSB repair toward non-crossover synthesis-dependent strand annealing (SDSA) by counteracting RAD51's inhibition of RAD52-mediated annealing [PMID:24319145], a subpathway choice further partitioned with ATRX through PCNA binding [PMID:33431668]. RECQL5 acts genetically in a BLM-independent pathway to suppress sister chromatid exchange [PMID:15831450]. In transcription, RECQL5 is the only human RecQ that directly associates with RNA Polymerase II via the RPB1 subunit [PMID:18562274], binding the Ser2,5-phosphorylated CTD through an SRI motif and the Pol II body through a KIX domain [PMID:20705653, PMID:20231364], thereby acting as an elongation roadblock independent of helicase activity [PMID:19570979]; cryo-EM structures show RECQL5 contacts the Rpb1 jaw at the TFIIS-binding site and uses a 'brake helix' to control Pol II translocation state, suppressing transcription-coupled repair-mediated Pol II ubiquitination [PMID:23748380, PMID:40624164, PMID:40624163]. Loss of RECQL5 produces transcription stress, RNAPII accumulation, and transcription-associated DSBs, linking its elongation control to genome protection [PMID:21402780, PMID:24836610]. RECQL5 additionally cooperates with the MRN complex, which recruits it to DSBs and whose MRE11 exonuclease it inhibits [PMID:19270065, PMID:22633600]; promotes MUS81-EME1-dependent mitotic DNA synthesis at common fragile sites via CDK1-dependent Ser727 phosphorylation [PMID:28575661]; stimulates Topoisomerase IIα decatenation [PMID:22013166] and PIAS1-SRSF1-mediated TOP1 SUMOylation [PMID:25851487]; counteracts replication fork stalling and excessive RAD51-driven fork reversal through PCNA binding [PMID:27502483, PMID:41099703]; and functions in the nucleolus in pre-rRNA processing, where it recognizes and unwinds pre-rRNA to prevent R-loop-driven ATR activation [PMID:40823811].","teleology":[{"year":2000,"claim":"Established the first cellular and partner context for RECQL5 by showing isoform-specific localization and topoisomerase association, framing the nuclear RecQ5beta isoform as the functionally relevant form.","evidence":"Immunocytochemistry of tagged isoforms and immunoprecipitation in 293EBNA cells","pmids":["10710432"],"confidence":"Medium","gaps":["Did not assign a biochemical activity to the helicase","Topo3alpha/3beta interaction not tied to a pathway"]},{"year":2005,"claim":"Resolved whether RECQL5 has a unique anti-recombination role by showing it suppresses crossovers in a pathway genetically separable from BLM.","evidence":"Blm/Recql5 single and double knockout mouse ES cells and MEFs with SCE assay","pmids":["15831450"],"confidence":"High","gaps":["Molecular substrate of suppression not defined","Did not establish the biochemical mechanism"]},{"year":2007,"claim":"Defined the core anti-recombinase mechanism by demonstrating RECQL5 directly disrupts RAD51 presynaptic filaments and blocks D-loop formation, explaining its HR-suppressive function.","evidence":"Purified-protein D-loop and ssDNA displacement assays, EM, ATPase-mutant controls","pmids":["18003859"],"confidence":"High","gaps":["Translocation versus passive displacement not distinguished","RAD51-interaction domain not yet mapped"]},{"year":2008,"claim":"Linked RECQL5 to transcription and to tumor suppression in vivo, revealing a second functional axis and disease relevance.","evidence":"Chromatin proteomics and direct interaction assays identifying RPB1 binding; Recql5 knockout mouse tumor and HR analyses","pmids":["18562274","18003859"],"confidence":"High","gaps":["Interaction interface and elongation consequence not yet defined","How transcription role connects to cancer phenotype unresolved"]},{"year":2009,"claim":"Established RECQL5's mechanism of transcriptional inhibition and its DSB-recruitment route, separating helicase-independent roadblock function from MRN-mediated targeting.","evidence":"Reconstituted in vitro transcription with interaction-deficient mutant; purified MRN interaction, exonuclease and laser-damage recruitment assays","pmids":["19570979","19270065"],"confidence":"High","gaps":["CTD-phosphorylation specificity of binding not yet defined","Physiological consequence of MRE11 inhibition unclear"]},{"year":2010,"claim":"Dissected the bipartite RNAPII engagement (SRI binds elongating Pol IIo CTD; KIX binds both forms) and mapped the RAD51-interacting domain, separating the transcription and recombination interfaces.","evidence":"CTD phospho-variant binding, ChIP, domain mapping and point mutants, ssDNA displacement, HR reporter, complex purification with MS","pmids":["20705653","20231364","20348101"],"confidence":"High","gaps":["Structural basis of Pol II contact not yet resolved","Whether KIX and helicase act jointly on chromatin unresolved"]},{"year":2011,"claim":"Connected the transcription axis to genome stability and identified additional partners, showing SRI-dependent prevention of transcription-associated DSBs and TOP2alpha decatenation stimulation.","evidence":"SRI mutants with RNAPII ChIP and gammaH2AX; transcription-inhibitor epistasis; TOP2alpha decatenation and depletion phenotyping","pmids":["21402780","22013166"],"confidence":"High","gaps":["Direct cause of breaks (collision vs R-loop) not yet defined","TOP2alpha stimulation mechanism uncharacterized"]},{"year":2012,"claim":"Defined the BRCv RAD51-interaction module and broadened partner/repair context, mapping recruitment requirements and adding WRN cooperation and BER/SSB involvement.","evidence":"BRCv mutagenesis with D-loop/SCE/drug assays; domain-mutant DSB recruitment imaging; WRN helicase-stimulation and synthetic lethality; laser SSB recruitment and BER protein analysis","pmids":["22645136","22633600","23180761","28180303","22973052"],"confidence":"High","gaps":["WRN and BER roles rest on single-lab medium-confidence data","Hierarchy among recruitment cues unresolved"]},{"year":2013,"claim":"Provided structural and pathway-level mechanism, showing RECQL5 sterically blocks elongation by mimicking the Pol II-TFIIS interaction and channels DSB repair toward non-crossover SDSA.","evidence":"Cryo-EM of Pol II-RECQL5 plus KIX crystal structure and read-through assays; HR reporter, in vitro RAD52 annealing, RAD51 ChIP and SCE","pmids":["23748380","24319145"],"confidence":"High","gaps":["Allosteric basis of translocation control not yet resolved","In vivo balance between SDSA and other subpathways unclear"]},{"year":2014,"claim":"Demonstrated genome-wide that RECQL5 controls elongation kinetics and that loss causes transcription stress overlapping chromosomal breakpoints, establishing the elongation-roadblock function as protective.","evidence":"RNAPII ChIP-seq, RNA-seq, and copy-number analysis in RECQL5-depleted cells","pmids":["24836610"],"confidence":"High","gaps":["Direct molecular trigger of stress-associated breaks not defined","Gene-class selectivity of effect unresolved"]},{"year":2015,"claim":"Extended RECQL5's transcription-genome interface to topoisomerase regulation and R-loop control via TOP1 SUMOylation, plus PARP/PAR-dependent damage recruitment.","evidence":"In vivo SUMOylation, ChIP, S9.6 R-loop detection and site mutants; PAR-binding, recruitment imaging and PARP-inhibitor sensitivity","pmids":["25851487","26391948"],"confidence":"High","gaps":["PARP-dependent recruitment is medium-confidence single-lab","Whether SUMOylation control is direct enzymatic or scaffolding unclear"]},{"year":2016,"claim":"Connected RECQL5 to replication-transcription conflict resolution, showing it acts at both RNAPI- and RNAPII-transcribed loci via PCNA to promote fork progression and RAD18-dependent PCNA ubiquitination.","evidence":"Co-IP, immunofluorescence, DNA fiber assay, PCNA ubiquitination assay, PCNA-interaction domain mapping","pmids":["27502483"],"confidence":"High","gaps":["Mechanism of intermediate processing not fully defined","Relative contribution of helicase vs scaffolding unresolved"]},{"year":2017,"claim":"Defined a mitotic, CDK1-regulated role at common fragile sites and refined the helicase mechano-chemical cycle, integrating RAD51 filament disruption into MUS81-EME1-dependent mitotic DNA synthesis.","evidence":"Ser727 phospho-site mutants, MUS81 co-IP, CFS ChIP, in vitro cleavage assays; crystal structures (Open/Closed) with SAXS and activity mutagenesis","pmids":["28575661","28100692"],"confidence":"High","gaps":["How CDK1 timing coordinates with interphase functions unclear","Structural basis of DNA unwinding directionality limited"]},{"year":2020,"claim":"Showed alternative splicing of the KIX domain tunes RECQL5 between transcription repression and DSB repair, revealing isoform-level functional partitioning.","evidence":"RECQL5β1 isoform binding-affinity, in vitro transcription, MRE11 co-IP, and DNA repair rescue assays","pmids":["33197722"],"confidence":"Medium","gaps":["Single-lab isoform comparison without in vivo confirmation","Physiological abundance/regulation of isoform unknown"]},{"year":2021,"claim":"Resolved the filament-disruption mechanism at single-molecule resolution and the DSB subpathway logic, defining RECQL5 as a translocase whose ssDNA-motor activity competes with ATRX-dependent HR via PCNA.","evidence":"Single-molecule TIRF with RAD51 mutants and F666A interface mutant; HR subpathway/SCE assays with ATRX/MUS81/GEN1 epistasis and PCNA-domain analysis","pmids":["33332547","33431668"],"confidence":"High","gaps":["Inability to dismantle heteroduplex-bound RAD51 leaves post-synaptic limits","Coordination of competing PCNA-binding factors not fully defined"]},{"year":2025,"claim":"Delivered atomic-level mechanism of RECQL5's transcriptional braking and uncovered a nucleolar pre-rRNA processing role, broadening its genome-protective remit to RNA metabolism.","evidence":"Cryo-EM of stalled Pol II-RECQL5 complexes (brake helix, translocation control, TCR competition and Pol II ubiquitination); nucleolar localization, pre-rRNA co-IP, dsRNA unwinding, Northern blot, R-loop and ATR assays; fork-reversal restriction by fiber/PLA epistasis","pmids":["40624164","40624163","40823811","41099703"],"confidence":"High","gaps":["How nucleolar, transcription and replication functions are temporally partitioned unresolved","In vivo significance of TCR-ubiquitination suppression untested"]},{"year":null,"claim":"How RECQL5's distinct activities — RAD51 filament disruption, Pol II elongation control, fork-reversal restriction, and pre-rRNA processing — are coordinated, prioritized, and spatially partitioned within a cell remains unresolved.","evidence":"","pmids":[],"confidence":"High","gaps":["No unified model of how shared modules (helicase, PCNA, RAD51, RNAPII binding) are switched between functions","Condensate-scaffold organization rests on preprint-level data","Disease mechanism linking specific activity loss to cancer not dissected"]}],"mechanism_profile":{"molecular_activity":[{"term_id":"GO:0140657","term_label":"ATP-dependent activity","supporting_discovery_ids":[0,19,18]},{"term_id":"GO:0003677","term_label":"DNA binding","supporting_discovery_ids":[18,27]},{"term_id":"GO:0140097","term_label":"catalytic activity, acting on DNA","supporting_discovery_ids":[0,18,27]},{"term_id":"GO:0003723","term_label":"RNA binding","supporting_discovery_ids":[31,26]},{"term_id":"GO:0140098","term_label":"catalytic activity, acting on RNA","supporting_discovery_ids":[31]},{"term_id":"GO:0098772","term_label":"molecular function regulator activity","supporting_discovery_ids":[0,4,8,9]},{"term_id":"GO:0060090","term_label":"molecular adaptor activity","supporting_discovery_ids":[15,16,17]}],"localization":[{"term_id":"GO:0005654","term_label":"nucleoplasm","supporting_discovery_ids":[2]},{"term_id":"GO:0005634","term_label":"nucleus","supporting_discovery_ids":[1,5]},{"term_id":"GO:0005730","term_label":"nucleolus","supporting_discovery_ids":[31,16]},{"term_id":"GO:0000228","term_label":"nuclear chromosome","supporting_discovery_ids":[17,9]}],"pathway":[{"term_id":"R-HSA-73894","term_label":"DNA Repair","supporting_discovery_ids":[0,8,13,35]},{"term_id":"R-HSA-74160","term_label":"Gene expression (Transcription)","supporting_discovery_ids":[4,5,14,12]},{"term_id":"R-HSA-69306","term_label":"DNA Replication","supporting_discovery_ids":[16,32]},{"term_id":"R-HSA-1640170","term_label":"Cell Cycle","supporting_discovery_ids":[9,17]},{"term_id":"R-HSA-8953854","term_label":"Metabolism of RNA","supporting_discovery_ids":[31]},{"term_id":"R-HSA-1643685","term_label":"Disease","supporting_discovery_ids":[35]}],"complexes":["MRN (MRE11-RAD50-NBS1) complex","RNA Polymerase II elongation complex"],"partners":["RAD51","RPB1 (POLR2A)","MRE11","NBS1","MUS81","TOP2A","PCNA","WRN"],"other_free_text":[]}},"prefetch_data":{"uniprot":{"accession":"O94762","full_name":"ATP-dependent DNA helicase Q5","aliases":["DNA 3'-5' helicase RecQ5","DNA helicase, RecQ-like type 5","RecQ5","RecQ protein-like 5"],"length_aa":991,"mass_kda":108.9,"function":"DNA helicase that plays an important role in DNA replication, transcription and repair (PubMed:20643585, PubMed:22973052, PubMed:28100692). Probably unwinds DNA in a 3'-5' direction (Probable) (PubMed:28100692). Binds to the RNA polymerase II subunit POLR2A during transcription elongation and suppresses transcription-associated genomic instability (PubMed:20231364). Also associates with POLR1A and enforces the stability of ribosomal DNA arrays (PubMed:27502483). Plays an important role in mitotic chromosome separation after cross-over events and cell cycle progress (PubMed:22013166). Mechanistically, removes RAD51 filaments protecting stalled replication forks at common fragile sites and stimulates MUS81-EME1 endonuclease leading to mitotic DNA synthesis (PubMed:28575661). Required for efficient DNA repair, including repair of inter-strand cross-links (PubMed:23715498). Stimulates DNA decatenation mediated by TOP2A. Prevents sister chromatid exchange and homologous recombination. A core helicase fragment (residues 11-609) binds preferentially to splayed duplex, looped and ssDNA (PubMed:28100692)","subcellular_location":"Cytoplasm","url":"https://www.uniprot.org/uniprotkb/O94762/entry"},"depmap":{"release":"DepMap","has_data":true,"is_common_essential":false,"resolved_as":"","url":"https://depmap.org/portal/gene/RECQL5","classification":"Not Classified","n_dependent_lines":12,"n_total_lines":1208,"dependency_fraction":0.009933774834437087},"opencell":{"profiled":false,"resolved_as":"","ensg_id":"","cell_line_id":"","localizations":[],"interactors":[],"url":"https://opencell.sf.czbiohub.org/search/RECQL5","total_profiled":1310},"omim":[{"mim_id":"614695","title":"REGULATION OF NUCLEAR PRE-mRNA DOMAIN-CONTAINING 2; RPRD2","url":"https://www.omim.org/entry/614695"},{"mim_id":"614694","title":"REGULATION OF NUCLEAR PRE-mRNA DOMAIN-CONTAINING PROTEIN 1B; RPRD1B","url":"https://www.omim.org/entry/614694"},{"mim_id":"610347","title":"REGULATION OF NUCLEAR PRE-mRNA DOMAIN-CONTAINING PROTEIN 1A; RPRD1A","url":"https://www.omim.org/entry/610347"},{"mim_id":"604611","title":"RECQ PROTEIN-LIKE 2; RECQL2","url":"https://www.omim.org/entry/604611"},{"mim_id":"604610","title":"RECQ PROTEIN-LIKE 3; RECQL3","url":"https://www.omim.org/entry/604610"}],"hpa":{"profiled":true,"resolved_as":"","reliability":"Supported","locations":[{"location":"Nucleoplasm","reliability":"Supported"},{"location":"Cytosol","reliability":"Additional"}],"tissue_specificity":"Low tissue specificity","tissue_distribution":"Detected in all","driving_tissues":[],"url":"https://www.proteinatlas.org/search/RECQL5"},"hgnc":{"alias_symbol":["RecQ5","FLJ90603"],"prev_symbol":[]},"alphafold":{"accession":"O94762","domains":[{"cath_id":"3.40.50.300","chopping":"11-216","consensus_level":"high","plddt":92.6362,"start":11,"end":216},{"cath_id":"3.40.50.300","chopping":"224-445","consensus_level":"medium","plddt":92.0012,"start":224,"end":445},{"cath_id":"-","chopping":"911-985","consensus_level":"high","plddt":84.8612,"start":911,"end":985},{"cath_id":"1.10.8","chopping":"546-611","consensus_level":"high","plddt":84.3909,"start":546,"end":611}],"viewer_url":"https://alphafold.ebi.ac.uk/entry/O94762","model_url":"https://alphafold.ebi.ac.uk/files/AF-O94762-F1-model_v6.cif","pae_url":"https://alphafold.ebi.ac.uk/files/AF-O94762-F1-predicted_aligned_error_v6.png","plddt_mean":70.06},"mouse_models":{"mgi_url":"https://www.informatics.jax.org/marker/summary?nomen=RECQL5","jax_strain_url":"https://www.jax.org/strain/search?query=RECQL5"},"sequence":{"accession":"O94762","fasta_url":"https://rest.uniprot.org/uniprotkb/O94762.fasta","uniprot_url":"https://www.uniprot.org/uniprotkb/O94762/entry","alphafold_viewer_url":"https://alphafold.ebi.ac.uk/entry/O94762"}},"corpus_meta":[{"pmid":"18003859","id":"PMC_18003859","title":"RECQL5/Recql5 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RECQL5 promotes metastasis and resistance to cisplatin in non-small cell lung cancer.","date":"2020","source":"Life sciences","url":"https://pubmed.ncbi.nlm.nih.gov/33217443","citation_count":12,"is_preprint":false},{"pmid":"20333788","id":"PMC_20333788","title":"Effect of Recql5 deficiency on the intestinal tumor susceptibility of Apc(min) mice.","date":"2010","source":"World journal of gastroenterology","url":"https://pubmed.ncbi.nlm.nih.gov/20333788","citation_count":12,"is_preprint":false},{"pmid":"23715498","id":"PMC_23715498","title":"The RecQ helicase RECQL5 participates in psoralen-induced interstrand cross-link repair.","date":"2013","source":"Carcinogenesis","url":"https://pubmed.ncbi.nlm.nih.gov/23715498","citation_count":12,"is_preprint":false},{"pmid":"21278449","id":"PMC_21278449","title":"A Blm-Recql5 partnership in replication stress response.","date":"2011","source":"Journal of molecular cell 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determinant for camptothecin tolerance in human colorectal cancer cells.","date":"2011","source":"Bioscience reports","url":"https://pubmed.ncbi.nlm.nih.gov/21210765","citation_count":9,"is_preprint":false},{"pmid":"40624164","id":"PMC_40624164","title":"Structural insights into transcriptional regulation by the helicase RECQL5.","date":"2025","source":"Nature structural & molecular biology","url":"https://pubmed.ncbi.nlm.nih.gov/40624164","citation_count":8,"is_preprint":false},{"pmid":"26420964","id":"PMC_26420964","title":"Recql5 protects against lipopolysaccharide/D-galactosamine-induced liver injury in mice.","date":"2015","source":"World journal of gastroenterology","url":"https://pubmed.ncbi.nlm.nih.gov/26420964","citation_count":8,"is_preprint":false},{"pmid":"40624163","id":"PMC_40624163","title":"Structural basis of RECQL5-induced RNA polymerase II transcription braking and subsequent reactivation.","date":"2025","source":"Nature structural & molecular biology","url":"https://pubmed.ncbi.nlm.nih.gov/40624163","citation_count":7,"is_preprint":false},{"pmid":"23123473","id":"PMC_23123473","title":"RecQ5 interacts with Rad51 and is involved in resistance of Drosophila to cisplatin treatment.","date":"2012","source":"Biological & pharmaceutical bulletin","url":"https://pubmed.ncbi.nlm.nih.gov/23123473","citation_count":7,"is_preprint":false},{"pmid":"21968968","id":"PMC_21968968","title":"Purification of a novel RECQL5-SWI/SNF-RNAPII super complex.","date":"2010","source":"International journal of biochemistry and molecular biology","url":"https://pubmed.ncbi.nlm.nih.gov/21968968","citation_count":7,"is_preprint":false},{"pmid":"17157839","id":"PMC_17157839","title":"Relationships of Drosophila melanogaster RECQ5/QE to cell-cycle progression and DNA damage.","date":"2006","source":"FEBS letters","url":"https://pubmed.ncbi.nlm.nih.gov/17157839","citation_count":6,"is_preprint":false},{"pmid":"28180303","id":"PMC_28180303","title":"RECQL5 plays co-operative and complementary roles with WRN syndrome helicase.","date":"2017","source":"Nucleic acids research","url":"https://pubmed.ncbi.nlm.nih.gov/28180303","citation_count":6,"is_preprint":false},{"pmid":"37392863","id":"PMC_37392863","title":"Functional inhibition of RECQL5 helicase elicits non-homologous end joining response and sensitivity of breast cancers to PARP inhibitor.","date":"2023","source":"The international journal of biochemistry & cell biology","url":"https://pubmed.ncbi.nlm.nih.gov/37392863","citation_count":6,"is_preprint":false},{"pmid":"36230663","id":"PMC_36230663","title":"A Large Case-Control Study Performed in Spanish Population Suggests That RECQL5 Is the Only RECQ Helicase Involved in Breast Cancer Susceptibility.","date":"2022","source":"Cancers","url":"https://pubmed.ncbi.nlm.nih.gov/36230663","citation_count":5,"is_preprint":false},{"pmid":"41099703","id":"PMC_41099703","title":"Distinct roles of RECQL5 in RAD51-mediated fork reversal and transcription elongation.","date":"2025","source":"Nucleic acids research","url":"https://pubmed.ncbi.nlm.nih.gov/41099703","citation_count":4,"is_preprint":false},{"pmid":"40823811","id":"PMC_40823811","title":"RECQ5 mediates pre-rRNA processing in nucleolus.","date":"2025","source":"Nucleic acids research","url":"https://pubmed.ncbi.nlm.nih.gov/40823811","citation_count":3,"is_preprint":false},{"pmid":"37626846","id":"PMC_37626846","title":"Understanding the Human RECQ5 Helicase-Connecting the Dots from DNA to Clinics.","date":"2023","source":"Cells","url":"https://pubmed.ncbi.nlm.nih.gov/37626846","citation_count":3,"is_preprint":false},{"pmid":"23811565","id":"PMC_23811565","title":"RecQ5 protein translocation into the nucleus by a nuclear localization signal.","date":"2013","source":"Biological & pharmaceutical bulletin","url":"https://pubmed.ncbi.nlm.nih.gov/23811565","citation_count":3,"is_preprint":false},{"pmid":"33197722","id":"PMC_33197722","title":"RECQL5 KIX domain splicing isoforms have distinct functions in transcription repression and DNA damage response.","date":"2020","source":"DNA repair","url":"https://pubmed.ncbi.nlm.nih.gov/33197722","citation_count":2,"is_preprint":false},{"pmid":"25245292","id":"PMC_25245292","title":"Drosophila RecQ5 is involved in proper progression of early spermatogenesis.","date":"2014","source":"Biochemical and biophysical research communications","url":"https://pubmed.ncbi.nlm.nih.gov/25245292","citation_count":2,"is_preprint":false},{"pmid":"38577877","id":"PMC_38577877","title":"A Recql5 mutant facilitates complex CRISPR/Cas9-mediated chromosomal engineering in mouse zygotes.","date":"2024","source":"Genetics","url":"https://pubmed.ncbi.nlm.nih.gov/38577877","citation_count":2,"is_preprint":false},{"pmid":"39975028","id":"PMC_39975028","title":"Structural insights into transcriptional regulation by the helicase RECQL5.","date":"2025","source":"bioRxiv : the preprint server for 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Recombination","date":"2024-09-26","source":"bioRxiv","url":"https://doi.org/10.1101/2024.09.25.615014","citation_count":0,"is_preprint":true}],"cost":{"stage1":{"model":"claude-sonnet-4-6","input_tokens":37987,"output_tokens":8916,"usd":0.123851,"stage1_stop_reason":"end_turn"},"stage2":{"model":"claude-opus-4-8","input_tokens":18922,"output_tokens":6157,"usd":0.124268,"stage2_stop_reason":"end_turn"},"total_usd":0.248119,"stage1_batch_id":"msgbatch_01CNoDbkChHEkgrJnL7BwtGJ","stage2_batch_id":"msgbatch_016Y4x9E9Wg5VQDANj9quSQD","note":"batch pricing = 50% of standard"},"stage1_raw":"```json\n{\n  \"discoveries\": [\n    {\n      \"year\": 2007,\n      \"finding\": \"RECQL5 binds RAD51 recombinase and inhibits RAD51-mediated D-loop formation; it displaces RAD51 from single-stranded DNA (ssDNA) in a reaction requiring ATP hydrolysis and RPA, thereby disrupting RAD51 presynaptic filaments and suppressing homologous recombination.\",\n      \"method\": \"Purified protein biochemical assays (D-loop formation assay, ssDNA displacement assay), electron microscopy, ATPase mutant analysis\",\n      \"journal\": \"Genes & development\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1 / Strong — in vitro reconstitution with purified proteins, electron microscopy structural validation, ATP hydrolysis mutant controls; replicated in multiple subsequent studies\",\n      \"pmids\": [\"18003859\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2008,\n      \"finding\": \"RECQL5 (RECQ5) is a bona fide RNA polymerase II (RNAPII)-associated protein; the interaction is direct and mediated by the RPB1 subunit of RNAPII; RECQL5 is the only human RECQ family member that associates with RNAPII.\",\n      \"method\": \"Chromatin isolation, targeted proteomic analysis, direct interaction assay with purified proteins, co-immunoprecipitation\",\n      \"journal\": \"Proceedings of the National Academy of Sciences of the United States of America\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — direct biochemical interaction with purified proteins, chromatin fractionation, confirmed in multiple subsequent studies\",\n      \"pmids\": [\"18562274\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2000,\n      \"finding\": \"The large isoform RecQ5beta localizes exclusively in the nucleoplasm, while small isoforms RecQ5alpha and RecQ5gamma remain cytoplasmic; RecQ5beta interacts with topoisomerases 3alpha and 3beta but not topoisomerase 1.\",\n      \"method\": \"Immunocytochemical staining of tagged isoforms expressed in 293EBNA cells, immunoprecipitation\",\n      \"journal\": \"Nucleic acids research\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 3 / Moderate — immunoprecipitation and immunostaining, single lab, two orthogonal methods\",\n      \"pmids\": [\"10710432\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2005,\n      \"finding\": \"Recql5 and Blm have nonredundant roles in suppressing crossovers (sister chromatid exchange) in mouse cells; deletion of both Blm and Recql5 leads to an even higher SCE frequency than either single knockout, establishing a Recql5-dependent, Blm-independent pathway for suppressing crossovers during mitosis.\",\n      \"method\": \"Genetic knockout in mouse ES cells and MEFs, sister chromatid exchange assay\",\n      \"journal\": \"Molecular and cellular biology\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — genetic epistasis via double knockout, replicated in mouse ES cells and MEFs, confirmed by subsequent studies\",\n      \"pmids\": [\"15831450\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2009,\n      \"finding\": \"RECQL5 inhibits both initiation and elongation of RNAPII-dependent transcription in vitro; this inhibition requires its RNAPII-interaction domain but not its helicase activity.\",\n      \"method\": \"In vitro transcription assay reconstituted with purified general transcription factors and RNAPII, RNAPII-interaction-deficient RECQL5 mutant\",\n      \"journal\": \"The Journal of biological chemistry\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1 / Moderate — in vitro reconstituted transcription assay with mutagenesis, single lab but multiple orthogonal controls\",\n      \"pmids\": [\"19570979\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2010,\n      \"finding\": \"RECQL5 specifically binds the Ser2,5-phosphorylated C-terminal repeat domain (CTD) of RPB1 via a Set2-Rpb1-interacting (SRI) motif at its C-terminus; RECQL5 associates with RNAPII-transcribed genes in an SRI-dependent manner, with density correlating with Ser2-CTD phosphorylation marking productive elongation.\",\n      \"method\": \"Binding assays with CTD phosphorylation variants, chromatin immunoprecipitation (ChIP), SRI deletion/mutation analysis\",\n      \"journal\": \"Nucleic acids research\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — direct binding assay with phosphorylated CTD variants, ChIP in cells with domain mutants, single lab, multiple orthogonal methods\",\n      \"pmids\": [\"20705653\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2010,\n      \"finding\": \"RECQL5 interacts with RAD51 through a RAD51-interacting domain; RECQL5 mutants that fail to bind RAD51 retain normal ATPase activity but are impaired in displacing RAD51 from ssDNA, and ablation of RECQL5-RAD51 complex formation alleviates RECQL5's inhibitory effect on HR-mediated DSB repair.\",\n      \"method\": \"Mapping of RAD51-interacting domain, generation of binding-deficient point mutants, in vitro ssDNA displacement assay, HR reporter assay in cells\",\n      \"journal\": \"The Journal of biological chemistry\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1 / Moderate — domain mapping with mutagenesis, in vitro displacement assay, cellular HR reporter, single lab, multiple orthogonal methods\",\n      \"pmids\": [\"20348101\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2010,\n      \"finding\": \"RECQL5 interacts with RNAPII through both KIX (binds initiation form Pol IIa and elongation form Pol IIo) and SRI (binds only elongation form Pol IIo) domains; RECQL5 requires both helicase activity and KIX-mediated Pol II interaction for full suppression of sister chromatid exchange and resistance to camptothecin.\",\n      \"method\": \"Purification of RECQL5-associated complex, mass spectrometry identification, structural modeling-guided mutagenesis, SCE assay, drug sensitivity assay\",\n      \"journal\": \"Molecular and cellular biology\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — complex purification with MS identification, domain mutagenesis, functional cellular assays, single lab, multiple orthogonal methods\",\n      \"pmids\": [\"20231364\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2009,\n      \"finding\": \"RECQL5 is constitutively associated with the MRE11-RAD50-NBS1 (MRN) complex through direct interactions with both MRE11 and NBS1; RECQL5 specifically inhibits the 3'→5' exonuclease activity of MRE11; the MRN complex is required for recruitment of RECQL5 to sites of DNA damage.\",\n      \"method\": \"Purified protein interaction assays, co-immunoprecipitation, exonuclease activity assay, laser-induced damage recruitment (live cell imaging)\",\n      \"journal\": \"Nucleic acids research\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — purified protein interaction, enzymatic assay, live cell imaging, single lab, three orthogonal methods\",\n      \"pmids\": [\"19270065\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2011,\n      \"finding\": \"RECQL5 physically and functionally interacts with Topoisomerase IIα; RECQL5 stimulates the decatenation activity of Topoisomerase IIα in vitro; RECQL5 co-localizes with Topoisomerase IIα during S-phase; RECQL5 depletion causes G2/M arrest, undercondensed/entangled chromosomes, and phenotypes resembling Topoisomerase II inhibition.\",\n      \"method\": \"Direct interaction assay with purified proteins, decatenation assay, co-localization (immunofluorescence), stable knockdown cell lines, cell cycle analysis\",\n      \"journal\": \"Nucleic acids research\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — direct biochemical stimulation assay, co-localization, cell phenotype with depletion, single lab, multiple orthogonal methods\",\n      \"pmids\": [\"22013166\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2011,\n      \"finding\": \"The SRI domain of RECQL5 is important for suppressing spontaneous DSBs and the p53-dependent transcription stress response; in RECQL5-depleted cells, active RNAPII accumulates on chromatin and DNA breaks associate with RNAPII-dependent transcribed loci; transcription inhibition eliminates both RNAPII accumulation and spontaneous DSB formation.\",\n      \"method\": \"SRI domain mutants, RNAPII ChIP, γH2AX foci analysis, transcription inhibitor treatment, p53 reporter assay\",\n      \"journal\": \"Molecular and cellular biology\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — domain mutagenesis, ChIP, pharmacological epistasis, multiple readouts, single lab\",\n      \"pmids\": [\"21402780\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2012,\n      \"finding\": \"RECQL5 contains a BRC repeat variant (BRCv) that mediates interaction with RAD51 through two conserved motifs; mutations in either motif compromise RECQL5's ability to associate with RAD51, inhibit D-loop formation, suppress SCE, and confer resistance to camptothecin-induced replication stress.\",\n      \"method\": \"Identification and mutagenesis of BRCv domain, co-immunoprecipitation, D-loop inhibition assay, SCE assay, drug sensitivity assay\",\n      \"journal\": \"The Journal of biological chemistry\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — domain mapping with mutagenesis, in vitro biochemical assay, multiple cellular readouts, single lab\",\n      \"pmids\": [\"22645136\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2013,\n      \"finding\": \"Cryo-EM structure of elongating Pol II arrested in complex with RECQL5 shows that RECQL5 helicase domain is positioned to sterically block elongation; RECQL5 KIX domain contacts the Rpb1 jaw domain at a site overlapping the TFIIS binding site; RECQL5 interferes with TFIIS-promoted transcriptional read-through in vitro, representing structural mimicry of the Pol II-TFIIS interaction.\",\n      \"method\": \"Cryo-EM structure determination, crystal structure of KIX domain, in vitro transcription read-through assay, binding competition assay\",\n      \"journal\": \"Nature structural & molecular biology\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1 / Strong — cryo-EM structure plus crystal structure, in vitro functional validation, single lab but multiple orthogonal structural and biochemical methods\",\n      \"pmids\": [\"23748380\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2013,\n      \"finding\": \"RECQL5 promotes formation of non-crossover products during DSB-induced HR by acting during the post-synaptic phase of synthesis-dependent strand annealing (SDSA); RECQL5 counteracts the inhibitory effect of RAD51 on RAD52-mediated DNA annealing in vitro; RECQL5 deficiency increases RAD51 occupancy at DSB sites and elevates SCE upon inactivation of the Holliday junction dissolution pathway.\",\n      \"method\": \"HR reporter assay in cells, in vitro annealing assay with purified proteins, ChIP for RAD51 at DSB sites, SCE assay\",\n      \"journal\": \"Nucleic acids research\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — in vitro reconstitution, ChIP, cellular reporter assays, single lab, multiple orthogonal methods\",\n      \"pmids\": [\"24319145\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2014,\n      \"finding\": \"RECQL5 depletion causes a genome-wide shift in RNAPII density; loss of RECQL5 increases the average rate of RNAPII elongation concurrent with increased stalling, pausing, arrest, and/or backtracking (transcription stress); chromosomal breakpoints in RECQL5-depleted cells overlap with areas of elevated transcription stress.\",\n      \"method\": \"Genome-wide RNAPII ChIP-seq, chromosomal copy-number analysis, RNA-seq\",\n      \"journal\": \"Cell\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — genome-wide ChIP-seq with loss-of-function and gain-of-function experiments, multiple readouts, replicated by independent groups\",\n      \"pmids\": [\"24836610\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2015,\n      \"finding\": \"RECQL5 promotes SUMOylation of TOP1 at K391 and K436 by facilitating interaction between the PIAS1-SRSF1 E3 ligase complex and TOP1 in chromatin containing active RNAPII; this SUMOylation is necessary for TOP1 binding to RNAPIIo, recruitment of RNA splicing factors to transcribed chromatin, and reduction of R-loops; SUMOylation also negatively regulates TOP1 topoisomerase activity.\",\n      \"method\": \"In vivo SUMOylation assays, co-immunoprecipitation, ChIP, R-loop detection (S9.6 antibody), mutagenesis of SUMOylation sites\",\n      \"journal\": \"Nature communications\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — multiple orthogonal methods in vivo and in vitro, mutagenesis of SUMOylation sites, single lab\",\n      \"pmids\": [\"25851487\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2016,\n      \"finding\": \"RECQL5 associates with both RNAPI and RNAPII transcription complexes in DNA replication foci; RECQL5 counteracts replication fork stalling in RNAPI- and RNAPII-transcribed genes; RECQL5-deficient cells accumulate RAD18 foci and BRCA1-dependent RAD51 foci at sites of replication-transcription interference; RECQL5-PCNA interaction promotes RAD18-dependent PCNA ubiquitination and helicase activity promotes processing of replication intermediates.\",\n      \"method\": \"Co-immunoprecipitation, immunofluorescence, DNA fiber assay, PCNA ubiquitination assay, RECQL5-PCNA interaction domain mapping\",\n      \"journal\": \"The Journal of cell biology\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — multiple biochemical and cell-biological assays, single lab, multiple orthogonal methods\",\n      \"pmids\": [\"27502483\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2017,\n      \"finding\": \"RECQL5 associates with common fragile sites (CFSs) in early mitosis through physical interaction with MUS81, dependent on CDK1-mediated phosphorylation at Ser727; RECQL5 promotes MUS81-dependent mitotic DNA synthesis; RECQL5 alleviates the inhibitory effect of RAD51 on 3'-flap DNA cleavage by MUS81-EME1 through its RAD51 filament disruption activity; mutation of Ser727 or the RAD51-interacting domain impairs CFS expression and causes defective chromosome segregation.\",\n      \"method\": \"Co-immunoprecipitation, ChIP at CFS loci, DNA synthesis assay, in vitro cleavage assay with purified proteins, CDK1 phosphorylation assay, phosphorylation-site mutant analysis\",\n      \"journal\": \"Molecular cell\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — biochemical reconstitution, phosphorylation site mutagenesis, ChIP, cellular phenotype with multiple mutants, single lab, multiple orthogonal methods\",\n      \"pmids\": [\"28575661\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2017,\n      \"finding\": \"Crystal structures of the RECQL5 core helicase domain in 'Open' and 'Closed' conformations (with and without ADP) reveal the mechano-chemical cycle; SAXS shows the 'Open' form predominates in solution; structure-guided mutagenesis defines residues important for ATPase, helicase, and DNA binding activities.\",\n      \"method\": \"X-ray crystallography, small-angle X-ray scattering (SAXS), ATPase assay, helicase assay, mutagenesis\",\n      \"journal\": \"Nucleic acids research\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1 / Moderate — crystal structures with SAXS validation and functional mutagenesis, single lab, multiple orthogonal structural and biochemical methods\",\n      \"pmids\": [\"28100692\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2021,\n      \"finding\": \"Single-molecule imaging shows RECQL5 is an ATP-dependent ssDNA motor protein that translocates on RPA-coated ssDNA and on RAD51-coated ssDNA, readily dismantling RAD51-ssDNA filaments; disruption of the RECQL5-RAD51 protein-protein interface (F666A mutation) reduces translocation velocity ~50%; RECQL5 can remove ATP-hydrolysis-deficient RAD51-K133R and the enhanced-binding RAD51-I287T mutant from ssDNA; RECQL5 cannot dismantle RAD51-bound heteroduplex joint molecules.\",\n      \"method\": \"Single-molecule TIRF imaging, ensemble kinetic assays, purified protein reconstitution, RECQL5-F666A mutant analysis\",\n      \"journal\": \"Nucleic acids research\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1 / Strong — single-molecule imaging plus ensemble assays with reconstituted components and multiple mutants; mechanistic detail on translocation and filament disruption independently validated\",\n      \"pmids\": [\"33332547\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2021,\n      \"finding\": \"ATRX-dependent HR outcompetes RECQL5-dependent SDSA for repair of most two-ended DSBs; subpathway choice depends on interaction of both ATRX and RECQL5 with PCNA; RECQL5-dependent SDSA prevents CO formation as assessed by SCE measurements.\",\n      \"method\": \"HR subpathway reporter assays, SCE assay, PCNA interaction domain analysis, genetic epistasis with ATRX/RECQL5/MUS81/GEN1 knockouts\",\n      \"journal\": \"Proceedings of the National Academy of Sciences of the United States of America\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — epistasis analysis with multiple knockouts, PCNA interaction domain requirement, SCE assay, single lab, multiple orthogonal methods\",\n      \"pmids\": [\"33431668\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2012,\n      \"finding\": \"Both the helicase and KIX domains of RECQL5 are required for its recruitment to DSBs; the MRN complex recruits RECQL5 to DSBs independently of its exonuclease activity; RECQL5 recruitment is also independent of transcription by RNAPII, of BLM, WRN, and ATM.\",\n      \"method\": \"Live cell confocal imaging with domain deletion mutants, laser-induced DSB recruitment assay, co-depletion experiments\",\n      \"journal\": \"DNA repair\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 3 / Moderate — live cell imaging with domain mutants and genetic controls, single lab\",\n      \"pmids\": [\"22633600\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2012,\n      \"finding\": \"RECQL5 interacts physically and functionally with WRN helicase; RECQL5 co-operates with WRN on stalled replication fork-like structures and stimulates WRN helicase activity on DNA fork duplexes; both proteins re-localize from nucleolus to nucleus after replicative stress; RECQL5 is essential for cell survival in the absence of WRN (synthetic lethality).\",\n      \"method\": \"Co-immunoprecipitation, in vitro helicase stimulation assay, immunofluorescence co-localization, double knockout cell viability assay\",\n      \"journal\": \"Nucleic acids research\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — in vitro helicase stimulation with purified proteins, co-IP, cellular co-localization, genetic synthetic lethality, single lab, multiple orthogonal methods\",\n      \"pmids\": [\"23180761\", \"28180303\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2012,\n      \"finding\": \"RECQL5 depletion causes sensitivity to oxidative stress, accumulation of endogenous DNA damage, increased poly(ADP-ribosyl)ation response, and accumulation at laser-induced single-strand breaks (not DSBs); RECQL5 depletion affects PARP-1 and XRCC1 protein levels, suggesting RECQL5 participates in base excision repair.\",\n      \"method\": \"Laser microirradiation (SSB vs DSB), comet assay, immunofluorescence, western blot for PARP-1 and XRCC1, siRNA knockdown\",\n      \"journal\": \"Molecular biology of the cell\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 3 / Moderate — multiple cellular assays, live cell imaging, single lab\",\n      \"pmids\": [\"22973052\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2010,\n      \"finding\": \"RECQL5 is identified within a super complex containing SWI/SNF chromatin remodeling complex and RNAPII core complex; RECQL5 is detected in the RNAPII holoenzyme but not purified RNAPII core complex.\",\n      \"method\": \"Biochemical purification of complex, co-immunoprecipitation, mass spectrometry\",\n      \"journal\": \"International journal of biochemistry and molecular biology\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 3 / Weak — single co-purification/co-IP approach, single lab\",\n      \"pmids\": [\"21968968\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2015,\n      \"finding\": \"PARP1 and PAR (poly(ADP-ribose)) regulate RECQL5 activity and recruitment to laser-induced DNA damage; PARylation is involved in recruitment of RECQL5 to damage sites; RECQL5 interacts noncovalently with PAR; PARP inhibition causes increased sensitivity in RECQL5-depleted cells.\",\n      \"method\": \"Laser microirradiation recruitment assay, in vitro PAR-binding assay, co-immunoprecipitation with PARP1, PARP inhibitor sensitivity assay\",\n      \"journal\": \"Molecular and cellular biology\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Weak — direct PAR-binding assay and recruitment imaging, single lab, limited mechanistic depth\",\n      \"pmids\": [\"26391948\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2015,\n      \"finding\": \"RECQL5 possesses relatively strong strand annealing activity on long and short duplexed substrates compared to other RecQ helicases; unlike other RecQs, its annealing activity is not inhibited by ATP; RECQL5 efficiently catalyzes RNA-to-DNA annealing in vitro in presence or absence of ATP.\",\n      \"method\": \"In vitro strand annealing assays with purified proteins, comparison across all five human RecQ helicases, ATP titration\",\n      \"journal\": \"DNA repair\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 1 / Weak — in vitro biochemical assay with purified proteins, single lab\",\n      \"pmids\": [\"26717024\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2016,\n      \"finding\": \"RECQL5 can unfold G-quadruplex (GQ) DNA structures in a single-molecule assay, but with ~10-fold weaker activity than BLM and WRN; RECQL5 demonstrates ssDNA reeling activity comparable to BLM; GQ unfolding and ssDNA reeling activities are not coupled for RECQL5.\",\n      \"method\": \"Single-molecule FRET imaging, multiple GQ substrates, ATP concentration titration\",\n      \"journal\": \"Biophysical journal\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 1 / Weak — single-molecule assay with purified protein, single lab\",\n      \"pmids\": [\"27332117\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2020,\n      \"finding\": \"An alternative splicing isoform of RECQL5 (RECQL5β1) containing 17 extra amino acids in the KIX domain has markedly decreased binding affinity to RNAPII, weaker transcription elongation repression activity, but stronger binding to MRE11 and enhanced DSB repair activity compared to canonical RECQL5β.\",\n      \"method\": \"Isoform identification, binding affinity assay, in vitro transcription assay, co-immunoprecipitation with MRE11, DNA repair assay in rescue cells\",\n      \"journal\": \"DNA repair\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Weak — binding and functional assays with isoform comparison, single lab\",\n      \"pmids\": [\"33197722\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2025,\n      \"finding\": \"Cryo-EM structures of stalled human Pol II elongation complexes bound to RECQL5 reveal that RECQL5 contacts the Rpb1 jaw domain acting as a transcriptional roadblock; in its nucleotide-free state RECQL5 twists the downstream DNA in the elongation complex; upon nucleotide binding, RECQL5 undergoes a conformational change that allosterically induces Pol II toward a post-translocation state.\",\n      \"method\": \"Cryo-electron microscopy structure determination of Pol II EC-RECQL5 complexes, in vitro transcription assays\",\n      \"journal\": \"Nature structural & molecular biology\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1 / Moderate — cryo-EM structures with functional biochemical validation, peer-reviewed publication\",\n      \"pmids\": [\"40624164\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2025,\n      \"finding\": \"Cryo-EM structures of RECQL5 bound to multiple Pol II elongation complexes reveal an α-helix of RECQL5 ('brake helix') responsible for binding Pol II and slowing transcription elongation; the transcription-coupled DNA repair (TCR) complex allows Pol II to overcome RECQL5-induced braking through concerted translocase activity and competition with RECQL5 for Pol II engagement; RECQL5 inhibits TCR-mediated Pol II ubiquitination to prevent activation of DNA repair pathway.\",\n      \"method\": \"Cryo-EM structure determination, biochemical transcription elongation assay, RECQL5 deletion/mutation analysis, TCR complex competition assay, Pol II ubiquitination assay\",\n      \"journal\": \"Nature structural & molecular biology\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1 / Moderate — cryo-EM structures with functional biochemical validation of multiple mechanisms, peer-reviewed publication\",\n      \"pmids\": [\"40624163\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2025,\n      \"finding\": \"RECQL5 localizes to the dense fibrillar component of the nucleolus, associates with pre-rRNA processing factors, recognizes pre-rRNA, and can unwind double-stranded RNA in vitro; loss of RECQL5 causes accumulation of 47S, 30SL5', and 30S pre-rRNA and reduction of 21S pre-rRNA, indicating a role in pre-rRNA processing; loss of RECQL5 causes unprocessed pre-rRNA to hybridize with rDNA, triggering R-loop formation and ATR activation.\",\n      \"method\": \"Immunofluorescence/co-localization, co-immunoprecipitation with pre-rRNA processing factors, in vitro dsRNA unwinding assay, Northern blot for pre-rRNA intermediates, R-loop detection (S9.6), ATR activation assay\",\n      \"journal\": \"Nucleic acids research\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — in vitro RNA unwinding assay, Northern blot for specific pre-rRNA species, R-loop and ATR assays, co-IP with processing factors, single lab, multiple orthogonal methods\",\n      \"pmids\": [\"40823811\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2025,\n      \"finding\": \"RECQL5 localizes to stalled replication fork sites and restricts RAD51-mediated excessive fork reversal to promote unrestrained DNA synthesis; this function requires RECQL5 binding to PCNA, RAD51, and helicase activity but is independent of its RNAPII interaction; notably, the RECQL5 mutant lacking RAD51 interaction still regulates transcription elongation comparably to wild-type, demonstrating that fork reversal regulation and transcription elongation regulation are molecularly distinct functions.\",\n      \"method\": \"DNA fiber assay, proximity ligation assay at forks, co-depletion epistasis with SMARCAL1/ZRANB3/HLTF/FBH1, HR-defective RAD51 mutant rescue, PCNA-interaction and RNAPII-interaction domain mutants\",\n      \"journal\": \"Nucleic acids research\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — multiple domain mutants, genetic epistasis with fork remodelers, fiber assay, single lab, multiple orthogonal methods\",\n      \"pmids\": [\"41099703\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2025,\n      \"finding\": \"RECQL5 uses a 'brake helix' as a doorstop to control RNAPII translocation along DNA at the atomic level; at the mesoscale level RECQL5 forms a condensate scaffold matrix integrating phosphorylated RNAPII elongation complex through site-specific interactions.\",\n      \"method\": \"Cryo-EM, cryo-electron tomography, coarse-grained molecular simulations, biochemical reconstitution\",\n      \"journal\": \"bioRxiv\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 1 / Weak — structural and simulation data from preprint, not yet peer-reviewed\",\n      \"pmids\": [\"bio_10.1101_2025.02.05.636647\"],\n      \"is_preprint\": true\n    },\n    {\n      \"year\": 2024,\n      \"finding\": \"IWS1 protects the activated transcription elongation complex from RECQL5 inhibition by binding the RPB1 jaw domain competitively with RECQL5, both of which share this binding site.\",\n      \"method\": \"Cryo-EM structure of elongation complexes, binding competition assay, functional transcription assay\",\n      \"journal\": \"bioRxiv\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 1 / Weak — cryo-EM and functional assay from preprint, finding about RECQL5 is ancillary to main IWS1 paper\",\n      \"pmids\": [\"bio_10.1101_2025.08.28.672863\"],\n      \"is_preprint\": true\n    },\n    {\n      \"year\": 2008,\n      \"finding\": \"Deletion of Recql5 in mice results in cancer susceptibility; Recql5-deficient cells exhibit elevated frequencies of spontaneous DNA double-strand breaks and HR events, and are prone to gross chromosomal rearrangements under replication stress.\",\n      \"method\": \"Mouse knockout, tumor incidence analysis, HR reporter assay, chromosomal rearrangement assay\",\n      \"journal\": \"Genes & development\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — knockout mouse model with multiple cellular readouts, replicated by subsequent studies\",\n      \"pmids\": [\"18003859\"],\n      \"is_preprint\": false\n    }\n  ],\n  \"current_model\": \"RECQL5 is a multifunctional RecQ DNA helicase that safeguards genome stability through at least three mechanistically distinct activities: (1) it disrupts RAD51 presynaptic filaments on ssDNA in an ATP hydrolysis- and RPA-dependent manner via a BRC-repeat variant (BRCv) domain, suppressing inappropriate homologous recombination and promoting SDSA over crossover-prone pathways; (2) it binds the phosphorylated CTD of elongating RNA Polymerase II via SRI and KIX domains, acts as a transcriptional roadblock that slows Pol II elongation and controls RNAPII translocation state as revealed by cryo-EM, thereby preventing transcription stress and transcription-replication conflicts; and (3) it cooperates with MUS81-EME1 endonuclease at common fragile sites during mitosis, requires CDK1-dependent phosphorylation (Ser727), stimulates Topoisomerase IIα decatenation activity, facilitates pre-rRNA processing in the nucleolus, and interacts with the MRN complex for recruitment to DNA double-strand breaks, collectively positioning RECQL5 as a critical coordinator at the intersection of DNA replication, repair, and transcription.\"\n}\n```","stage2_raw":"{\n  \"mechanistic_narrative\": \"RECQL5 is a multifunctional RecQ-family DNA helicase that safeguards genome stability at the interface of DNA replication, repair, and transcription, and its loss in mice causes cancer susceptibility together with spontaneous DSBs, elevated homologous recombination, and replication-stress-induced chromosomal rearrangements [#35]. In recombination, RECQL5 binds RAD51 and disrupts RAD51 presynaptic filaments on ssDNA in an ATP-hydrolysis- and RPA-dependent manner, inhibiting D-loop formation and suppressing inappropriate recombination [#0]; single-molecule imaging established it as an ATP-dependent ssDNA translocase that actively dismantles RAD51 filaments, with translocation enhanced by a direct RECQL5-RAD51 interface [#19]. This RAD51-interaction is mediated by a BRC-repeat-variant (BRCv) domain whose mutation impairs filament disruption, SCE suppression, and camptothecin resistance [#6, #11], and functionally channels DSB repair toward non-crossover synthesis-dependent strand annealing (SDSA) by counteracting RAD51's inhibition of RAD52-mediated annealing [#13], a subpathway choice further partitioned with ATRX through PCNA binding [#20]. RECQL5 acts genetically in a BLM-independent pathway to suppress sister chromatid exchange [#3]. In transcription, RECQL5 is the only human RecQ that directly associates with RNA Polymerase II via the RPB1 subunit [#1], binding the Ser2,5-phosphorylated CTD through an SRI motif and the Pol II body through a KIX domain [#5, #7], thereby acting as an elongation roadblock independent of helicase activity [#4]; cryo-EM structures show RECQL5 contacts the Rpb1 jaw at the TFIIS-binding site and uses a 'brake helix' to control Pol II translocation state, suppressing transcription-coupled repair-mediated Pol II ubiquitination [#12, #29, #30]. Loss of RECQL5 produces transcription stress, RNAPII accumulation, and transcription-associated DSBs, linking its elongation control to genome protection [#10, #14]. RECQL5 additionally cooperates with the MRN complex, which recruits it to DSBs and whose MRE11 exonuclease it inhibits [#8, #21]; promotes MUS81-EME1-dependent mitotic DNA synthesis at common fragile sites via CDK1-dependent Ser727 phosphorylation [#17]; stimulates Topoisomerase IIα decatenation [#9] and PIAS1-SRSF1-mediated TOP1 SUMOylation [#15]; counteracts replication fork stalling and excessive RAD51-driven fork reversal through PCNA binding [#16, #32]; and functions in the nucleolus in pre-rRNA processing, where it recognizes and unwinds pre-rRNA to prevent R-loop-driven ATR activation [#31].\",\n  \"teleology\": [\n    {\n      \"year\": 2000,\n      \"claim\": \"Established the first cellular and partner context for RECQL5 by showing isoform-specific localization and topoisomerase association, framing the nuclear RecQ5beta isoform as the functionally relevant form.\",\n      \"evidence\": \"Immunocytochemistry of tagged isoforms and immunoprecipitation in 293EBNA cells\",\n      \"pmids\": [\"10710432\"],\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"\",\n      \"gaps\": [\"Did not assign a biochemical activity to the helicase\", \"Topo3alpha/3beta interaction not tied to a pathway\"]\n    },\n    {\n      \"year\": 2005,\n      \"claim\": \"Resolved whether RECQL5 has a unique anti-recombination role by showing it suppresses crossovers in a pathway genetically separable from BLM.\",\n      \"evidence\": \"Blm/Recql5 single and double knockout mouse ES cells and MEFs with SCE assay\",\n      \"pmids\": [\"15831450\"],\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"\",\n      \"gaps\": [\"Molecular substrate of suppression not defined\", \"Did not establish the biochemical mechanism\"]\n    },\n    {\n      \"year\": 2007,\n      \"claim\": \"Defined the core anti-recombinase mechanism by demonstrating RECQL5 directly disrupts RAD51 presynaptic filaments and blocks D-loop formation, explaining its HR-suppressive function.\",\n      \"evidence\": \"Purified-protein D-loop and ssDNA displacement assays, EM, ATPase-mutant controls\",\n      \"pmids\": [\"18003859\"],\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"\",\n      \"gaps\": [\"Translocation versus passive displacement not distinguished\", \"RAD51-interaction domain not yet mapped\"]\n    },\n    {\n      \"year\": 2008,\n      \"claim\": \"Linked RECQL5 to transcription and to tumor suppression in vivo, revealing a second functional axis and disease relevance.\",\n      \"evidence\": \"Chromatin proteomics and direct interaction assays identifying RPB1 binding; Recql5 knockout mouse tumor and HR analyses\",\n      \"pmids\": [\"18562274\", \"18003859\"],\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"\",\n      \"gaps\": [\"Interaction interface and elongation consequence not yet defined\", \"How transcription role connects to cancer phenotype unresolved\"]\n    },\n    {\n      \"year\": 2009,\n      \"claim\": \"Established RECQL5's mechanism of transcriptional inhibition and its DSB-recruitment route, separating helicase-independent roadblock function from MRN-mediated targeting.\",\n      \"evidence\": \"Reconstituted in vitro transcription with interaction-deficient mutant; purified MRN interaction, exonuclease and laser-damage recruitment assays\",\n      \"pmids\": [\"19570979\", \"19270065\"],\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"\",\n      \"gaps\": [\"CTD-phosphorylation specificity of binding not yet defined\", \"Physiological consequence of MRE11 inhibition unclear\"]\n    },\n    {\n      \"year\": 2010,\n      \"claim\": \"Dissected the bipartite RNAPII engagement (SRI binds elongating Pol IIo CTD; KIX binds both forms) and mapped the RAD51-interacting domain, separating the transcription and recombination interfaces.\",\n      \"evidence\": \"CTD phospho-variant binding, ChIP, domain mapping and point mutants, ssDNA displacement, HR reporter, complex purification with MS\",\n      \"pmids\": [\"20705653\", \"20231364\", \"20348101\"],\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"\",\n      \"gaps\": [\"Structural basis of Pol II contact not yet resolved\", \"Whether KIX and helicase act jointly on chromatin unresolved\"]\n    },\n    {\n      \"year\": 2011,\n      \"claim\": \"Connected the transcription axis to genome stability and identified additional partners, showing SRI-dependent prevention of transcription-associated DSBs and TOP2alpha decatenation stimulation.\",\n      \"evidence\": \"SRI mutants with RNAPII ChIP and gammaH2AX; transcription-inhibitor epistasis; TOP2alpha decatenation and depletion phenotyping\",\n      \"pmids\": [\"21402780\", \"22013166\"],\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"\",\n      \"gaps\": [\"Direct cause of breaks (collision vs R-loop) not yet defined\", \"TOP2alpha stimulation mechanism uncharacterized\"]\n    },\n    {\n      \"year\": 2012,\n      \"claim\": \"Defined the BRCv RAD51-interaction module and broadened partner/repair context, mapping recruitment requirements and adding WRN cooperation and BER/SSB involvement.\",\n      \"evidence\": \"BRCv mutagenesis with D-loop/SCE/drug assays; domain-mutant DSB recruitment imaging; WRN helicase-stimulation and synthetic lethality; laser SSB recruitment and BER protein analysis\",\n      \"pmids\": [\"22645136\", \"22633600\", \"23180761\", \"28180303\", \"22973052\"],\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"\",\n      \"gaps\": [\"WRN and BER roles rest on single-lab medium-confidence data\", \"Hierarchy among recruitment cues unresolved\"]\n    },\n    {\n      \"year\": 2013,\n      \"claim\": \"Provided structural and pathway-level mechanism, showing RECQL5 sterically blocks elongation by mimicking the Pol II-TFIIS interaction and channels DSB repair toward non-crossover SDSA.\",\n      \"evidence\": \"Cryo-EM of Pol II-RECQL5 plus KIX crystal structure and read-through assays; HR reporter, in vitro RAD52 annealing, RAD51 ChIP and SCE\",\n      \"pmids\": [\"23748380\", \"24319145\"],\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"\",\n      \"gaps\": [\"Allosteric basis of translocation control not yet resolved\", \"In vivo balance between SDSA and other subpathways unclear\"]\n    },\n    {\n      \"year\": 2014,\n      \"claim\": \"Demonstrated genome-wide that RECQL5 controls elongation kinetics and that loss causes transcription stress overlapping chromosomal breakpoints, establishing the elongation-roadblock function as protective.\",\n      \"evidence\": \"RNAPII ChIP-seq, RNA-seq, and copy-number analysis in RECQL5-depleted cells\",\n      \"pmids\": [\"24836610\"],\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"\",\n      \"gaps\": [\"Direct molecular trigger of stress-associated breaks not defined\", \"Gene-class selectivity of effect unresolved\"]\n    },\n    {\n      \"year\": 2015,\n      \"claim\": \"Extended RECQL5's transcription-genome interface to topoisomerase regulation and R-loop control via TOP1 SUMOylation, plus PARP/PAR-dependent damage recruitment.\",\n      \"evidence\": \"In vivo SUMOylation, ChIP, S9.6 R-loop detection and site mutants; PAR-binding, recruitment imaging and PARP-inhibitor sensitivity\",\n      \"pmids\": [\"25851487\", \"26391948\"],\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"\",\n      \"gaps\": [\"PARP-dependent recruitment is medium-confidence single-lab\", \"Whether SUMOylation control is direct enzymatic or scaffolding unclear\"]\n    },\n    {\n      \"year\": 2016,\n      \"claim\": \"Connected RECQL5 to replication-transcription conflict resolution, showing it acts at both RNAPI- and RNAPII-transcribed loci via PCNA to promote fork progression and RAD18-dependent PCNA ubiquitination.\",\n      \"evidence\": \"Co-IP, immunofluorescence, DNA fiber assay, PCNA ubiquitination assay, PCNA-interaction domain mapping\",\n      \"pmids\": [\"27502483\"],\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"\",\n      \"gaps\": [\"Mechanism of intermediate processing not fully defined\", \"Relative contribution of helicase vs scaffolding unresolved\"]\n    },\n    {\n      \"year\": 2017,\n      \"claim\": \"Defined a mitotic, CDK1-regulated role at common fragile sites and refined the helicase mechano-chemical cycle, integrating RAD51 filament disruption into MUS81-EME1-dependent mitotic DNA synthesis.\",\n      \"evidence\": \"Ser727 phospho-site mutants, MUS81 co-IP, CFS ChIP, in vitro cleavage assays; crystal structures (Open/Closed) with SAXS and activity mutagenesis\",\n      \"pmids\": [\"28575661\", \"28100692\"],\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"\",\n      \"gaps\": [\"How CDK1 timing coordinates with interphase functions unclear\", \"Structural basis of DNA unwinding directionality limited\"]\n    },\n    {\n      \"year\": 2020,\n      \"claim\": \"Showed alternative splicing of the KIX domain tunes RECQL5 between transcription repression and DSB repair, revealing isoform-level functional partitioning.\",\n      \"evidence\": \"RECQL5β1 isoform binding-affinity, in vitro transcription, MRE11 co-IP, and DNA repair rescue assays\",\n      \"pmids\": [\"33197722\"],\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"\",\n      \"gaps\": [\"Single-lab isoform comparison without in vivo confirmation\", \"Physiological abundance/regulation of isoform unknown\"]\n    },\n    {\n      \"year\": 2021,\n      \"claim\": \"Resolved the filament-disruption mechanism at single-molecule resolution and the DSB subpathway logic, defining RECQL5 as a translocase whose ssDNA-motor activity competes with ATRX-dependent HR via PCNA.\",\n      \"evidence\": \"Single-molecule TIRF with RAD51 mutants and F666A interface mutant; HR subpathway/SCE assays with ATRX/MUS81/GEN1 epistasis and PCNA-domain analysis\",\n      \"pmids\": [\"33332547\", \"33431668\"],\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"\",\n      \"gaps\": [\"Inability to dismantle heteroduplex-bound RAD51 leaves post-synaptic limits\", \"Coordination of competing PCNA-binding factors not fully defined\"]\n    },\n    {\n      \"year\": 2025,\n      \"claim\": \"Delivered atomic-level mechanism of RECQL5's transcriptional braking and uncovered a nucleolar pre-rRNA processing role, broadening its genome-protective remit to RNA metabolism.\",\n      \"evidence\": \"Cryo-EM of stalled Pol II-RECQL5 complexes (brake helix, translocation control, TCR competition and Pol II ubiquitination); nucleolar localization, pre-rRNA co-IP, dsRNA unwinding, Northern blot, R-loop and ATR assays; fork-reversal restriction by fiber/PLA epistasis\",\n      \"pmids\": [\"40624164\", \"40624163\", \"40823811\", \"41099703\"],\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"\",\n      \"gaps\": [\"How nucleolar, transcription and replication functions are temporally partitioned unresolved\", \"In vivo significance of TCR-ubiquitination suppression untested\"]\n    },\n    {\n      \"year\": null,\n      \"claim\": \"How RECQL5's distinct activities — RAD51 filament disruption, Pol II elongation control, fork-reversal restriction, and pre-rRNA processing — are coordinated, prioritized, and spatially partitioned within a cell remains unresolved.\",\n      \"evidence\": \"\",\n      \"pmids\": [],\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"\",\n      \"gaps\": [\"No unified model of how shared modules (helicase, PCNA, RAD51, RNAPII binding) are switched between functions\", \"Condensate-scaffold organization rests on preprint-level data\", \"Disease mechanism linking specific activity loss to cancer not dissected\"]\n    }\n  ],\n  \"mechanism_profile\": {\n    \"molecular_activity\": [\n      {\"term_id\": \"GO:0140657\", \"supporting_discovery_ids\": [0, 19, 18]},\n      {\"term_id\": \"GO:0003677\", \"supporting_discovery_ids\": [18, 27]},\n      {\"term_id\": \"GO:0140097\", \"supporting_discovery_ids\": [0, 18, 27]},\n      {\"term_id\": \"GO:0003723\", \"supporting_discovery_ids\": [31, 26]},\n      {\"term_id\": \"GO:0140098\", \"supporting_discovery_ids\": [31]},\n      {\"term_id\": \"GO:0098772\", \"supporting_discovery_ids\": [0, 4, 8, 9]},\n      {\"term_id\": \"GO:0060090\", \"supporting_discovery_ids\": [15, 16, 17]}\n    ],\n    \"localization\": [\n      {\"term_id\": \"GO:0005654\", \"supporting_discovery_ids\": [2]},\n      {\"term_id\": \"GO:0005634\", \"supporting_discovery_ids\": [1, 5]},\n      {\"term_id\": \"GO:0005730\", \"supporting_discovery_ids\": [31, 16]},\n      {\"term_id\": \"GO:0000228\", \"supporting_discovery_ids\": [17, 9]}\n    ],\n    \"pathway\": [\n      {\"term_id\": \"R-HSA-73894\", \"supporting_discovery_ids\": [0, 8, 13, 35]},\n      {\"term_id\": \"R-HSA-74160\", \"supporting_discovery_ids\": [4, 5, 14, 12]},\n      {\"term_id\": \"R-HSA-69306\", \"supporting_discovery_ids\": [16, 32]},\n      {\"term_id\": \"R-HSA-1640170\", \"supporting_discovery_ids\": [9, 17]},\n      {\"term_id\": \"R-HSA-8953854\", \"supporting_discovery_ids\": [31]},\n      {\"term_id\": \"R-HSA-1643685\", \"supporting_discovery_ids\": [35]}\n    ],\n    \"complexes\": [\n      \"MRN (MRE11-RAD50-NBS1) complex\",\n      \"RNA Polymerase II elongation complex\"\n    ],\n    \"partners\": [\n      \"RAD51\",\n      \"RPB1 (POLR2A)\",\n      \"MRE11\",\n      \"NBS1\",\n      \"MUS81\",\n      \"TOP2A\",\n      \"PCNA\",\n      \"WRN\"\n    ],\n    \"other_free_text\": []\n  }\n}","audit_flag":null,"evaluation":{"pairwise":"win","faith_supported":7,"faith_total":7,"faith_pct":100.0}}