{"gene":"THOC5","run_date":"2026-06-10T10:51:55","timeline":{"discoveries":[{"year":2009,"finding":"THOC5 binds to a distinct, non-overlapping surface on the middle (Ntf2-like) domain of the Tap export receptor, allowing simultaneous binding of both THOC5 and the adaptor protein Aly to Tap-p15. THOC5 exhibits in vitro RNA-binding activity and associates with HSP70 mRNPs in vivo as a component of the stable THO complex. Nuclear export of HSP70 mRNA specifically requires both THOC5 and Aly, but THOC5 is not required for bulk mRNA export.","method":"Co-immunoprecipitation, in vitro binding assays (GST pulldown), RNA-binding assays, in vivo mRNA export assays with knockdown","journal":"The EMBO journal","confidence":"High","confidence_rationale":"Tier 2 / Strong — reciprocal binding assays (in vitro and in vivo), multiple orthogonal methods, functional export assay with knockdown","pmids":["19165146"],"is_preprint":false},{"year":1999,"finding":"THOC5/FMIP (MW ~78 kDa) binds transiently via its N-terminal 144 residues to the cytoplasmic domain of activated (ligand-stimulated) c-Fms tyrosine kinase receptor. Binding is followed by rapid tyrosine phosphorylation of FMIP within the binding domain, which drastically reduces its association with Fms. No binding was observed with the cytoplasmic domains of c-Kit, TrkA, c-Met, or the insulin receptor.","method":"Co-immunoprecipitation, GST-Fms fusion protein pulldown, deletion mutagenesis","journal":"Oncogene","confidence":"High","confidence_rationale":"Tier 2 / Moderate — reciprocal Co-IP and GST pulldown with deletion mutagenesis in single study","pmids":["10597251"],"is_preprint":false},{"year":2004,"finding":"THOC5/FMIP is phosphorylated by protein kinase C (PKC) on serines 5 and 6, adjacent to its nuclear localization signal (NLS). This NLS is essential for predominantly nuclear localization. PKC-mediated phosphorylation on S5/S6 causes translocation of THOC5 from nucleus to cytosol. Phosphomimetic mutations (SS5,6EE) promoted cytoplasmic localization and enhanced M-CSF-mediated survival/differentiation, while non-phosphorylatable mutant (SS5,6AA) remained nuclear even in the presence of activated PKCα.","method":"Site-directed mutagenesis (phosphomimetic and non-phosphorylatable mutants), subcellular fractionation/localization imaging, functional differentiation assay","journal":"Oncogene","confidence":"High","confidence_rationale":"Tier 1-2 / Moderate — mutagenesis with functional validation and localization assays, single lab but multiple orthogonal methods","pmids":["15221008"],"is_preprint":false},{"year":2008,"finding":"THOC7 lacks a typical nuclear localization signal (NLS) and resides mainly in the cytoplasm on its own, but directly binds to the N-terminal portion (residues 1-199) of THOC5/FMIP via THOC7 residues 50-137. This interaction is required for THOC5-dependent nuclear transport of THOC7: in the presence of THOC5, THOC7 is transported into the nucleus; a THOC7 mutant lacking the FMIP-binding site fails to co-localize with FMIP.","method":"Co-immunoprecipitation, deletion mutagenesis, subcellular localization imaging (co-transfection/co-localization)","journal":"FEBS letters","confidence":"High","confidence_rationale":"Tier 2 / Moderate — domain mapping by deletion mutagenesis plus functional localization assay, single lab","pmids":["19059247"],"is_preprint":false},{"year":2006,"finding":"THOC5/FMIP overexpression in C2C12 cells prevents adipocyte differentiation and promotes granulocyte/muscle phenotype, while FMIP knockdown promotes adipocyte lineage commitment and impairs muscle differentiation. Mechanistically, FMIP-overexpressing cells lack polyadenylated C/EBPα mRNA but retain C/EBPα pre-mRNA (detected by Northern blot and RT-PCR), implicating FMIP in RNA processing/export of C/EBPα. THOC1 co-precipitates with FMIP, placing it in the THO complex in this context.","method":"Ectopic expression and siRNA knockdown, Northern blot, RT-PCR, co-immunoprecipitation","journal":"Oncogene","confidence":"Medium","confidence_rationale":"Tier 2-3 / Moderate — multiple methods (overexpression, KD, RNA analysis, Co-IP) in single lab","pmids":["16909111"],"is_preprint":false},{"year":2010,"finding":"Conditional knockout of THOC5 in mice leads to rapid apoptosis of hematopoietic progenitor cells (committed myeloid progenitors and long-term reconstituting cells) within days, demonstrating THOC5 is essential for hematopoietic primitive cell survival in vivo. Mechanistically, THOC5 depletion causes down-regulation of its direct interacting partner THOC1, potentially disrupting THO complex function.","method":"Interferon-inducible conditional knockout mouse, bone marrow transplantation rescue, flow cytometry, histology","journal":"BMC biology","confidence":"High","confidence_rationale":"Tier 2 / Strong — clean conditional KO with defined cellular phenotype, rescue experiment, and mechanistic link to THOC1","pmids":["20051105"],"is_preprint":false},{"year":2011,"finding":"THOC5 is required for export of a specific subset (~10 identified) of mRNAs (including HoxB3, CBX2); these mRNAs are spliced but not exported to the cytoplasm in THOC5-depleted MEF cells and co-purify with THOC5. Hsp70 mRNA export is specifically dependent on THOC5 under heat shock (42°C) but not under normal conditions (37°C), indicating THOC5 is required for stress-induced mRNA export rather than basal export.","method":"Conditional knockout (Cre-lox MEF cells), transcriptome analysis of cytoplasmic RNA, RNA co-immunoprecipitation (RIP)","journal":"RNA (New York, N.Y.)","confidence":"High","confidence_rationale":"Tier 2 / Moderate — clean genetic KO with transcriptome and RIP validation, multiple orthogonal methods","pmids":["21525145"],"is_preprint":false},{"year":2013,"finding":"THOC5 physically interacts with CFIm68 (large subunit of mammalian cleavage factor I involved in polyadenylation site choice). Most likely via direct Thoc5–CFIm68 interaction. THOC5 depletion selectively attenuates expression of mRNAs polyadenylated at distal polyadenylation sites (phenocopying CFIm68 depletion) and globally reduces CFIm68 association with the 5' regions of genes (by ChIP-seq), indicating THOC5 controls polyadenylation site choice by co-transcriptional loading of CFIm68.","method":"Co-immunoprecipitation (antibodies against different TREX components), microarray, ChIP-seq, siRNA knockdown","journal":"Nucleic acids research","confidence":"High","confidence_rationale":"Tier 2 / Moderate — Co-IP, functional transcriptomics, and ChIP-seq in single lab with multiple orthogonal methods","pmids":["23685434"],"is_preprint":false},{"year":2013,"finding":"THOC5 is localized in nuclear speckles and translocates from nucleus to cytoplasm during M-CSF-induced macrophage differentiation. THOC5 is required for processing/export of a subset of M-CSF-inducible mRNAs (including Ets1); depletion causes accumulation of unspliced Ets1 mRNA in the nucleus. THOC5 is recruited to chromatin at the Ets1 gene locus and binds both unspliced and spliced Ets1 transcripts.","method":"Immunofluorescence/subcellular localization, tamoxifen-inducible conditional KO, transcriptome analysis, chromatin immunoprecipitation (ChIP), RNA immunoprecipitation (RIP)","journal":"Cell death & disease","confidence":"High","confidence_rationale":"Tier 2 / Moderate — clean genetic KO with multiple orthogonal methods (localization, transcriptomics, ChIP, RIP) in single lab","pmids":["24157873"],"is_preprint":false},{"year":2013,"finding":"THOC5 is required for processing and export of a subset of Wnt target mRNAs (Sox9 and Ascl2, but not Fn1) in intestinal epithelium; these mRNAs co-purify with THOC5 by RIP. THOC5 is also required for expression of the Toll-like receptor-inducible gene COX2/Ptgs2, whose transcript is a THOC5 target mRNA. THOC5 deficiency disrupts gut epithelial differentiation and self-renewal, causing bacterial translocation and sepsis in mice.","method":"Tamoxifen-inducible conditional knockout mouse, RNA co-immunoprecipitation (RIP), transcriptome analysis, histopathology","journal":"BMC cell biology","confidence":"High","confidence_rationale":"Tier 2 / Moderate — clean genetic KO, RIP validation, multiple orthogonal methods in single lab","pmids":["24267292"],"is_preprint":false},{"year":2014,"finding":"THOC5 forms a complex with polyadenylation-specific factor 100 (CPSF100) upon serum stimulation. THOC5 is required for recruitment of CPSF100 to the 3'UTR of THOC5 target genes (including Id1, Id3, Wnt11, Myc, Smad7). Without THOC5, a subset of IEG transcripts fail to be released from chromatin or are released with shortened 3'UTRs and impaired nuclear export. Over 90% of immediate-early genes fail to be induced by serum in THOC5-depleted cells.","method":"Interactome analysis (THOC5 as bait/MS), chromatin association assays, transcriptome analysis, serum stimulation experiments with siRNA knockdown","journal":"Nucleic acids research","confidence":"High","confidence_rationale":"Tier 2 / Moderate — MS-based interactome, chromatin fractionation, transcriptomics with multiple orthogonal methods in single lab","pmids":["25274738"],"is_preprint":false},{"year":2011,"finding":"ATM kinase pathway regulates THOC5 mRNA-binding activity in response to DNA damage. DNA damage decreases cytoplasmic levels of THOC5-dependent mRNAs and impairs THOC5/mRNA complex formation. The C-terminal domain of THOC5 (not phosphorylation at S307/312/314 in the PEST domain) is required for this regulatory response. ATM kinase inhibitor (KU55933) or siRNA against ATM or p53 restores THOC5-dependent mRNA export after DNA damage, indicating the ATM-p53 pathway suppresses THOC5 mRNA-binding ability.","method":"Site-directed mutagenesis (S307/312/314A and C-terminal deletion mutants), RNA immunoprecipitation (RIP), ATM kinase inhibitor treatment, siRNA knockdown of ATM and p53","journal":"RNA (New York, N.Y.)","confidence":"High","confidence_rationale":"Tier 1-2 / Moderate — mutagenesis, RIP, and pharmacological/genetic pathway epistasis in single lab with multiple orthogonal methods","pmids":["21937706"],"is_preprint":false},{"year":2012,"finding":"THOC5 phosphorylation on tyrosine 225 is mediated by Src PTK and reversed by CD45 protein tyrosine phosphatase, and is elevated in CML stem cells. This Y225 phosphorylation specifically governs THOC5 mRNA-binding activity (site-directed mutagenesis of Y225 modulates motile response to CXCL12). CXCL12 chemokine stimulation also induces THOC5 Y225 phosphorylation. THOC5 Y225 phosphorylation is sensitive to frontline CML drugs (imatinib).","method":"Site-directed mutagenesis (Y225), mass spectrometry (phosphorylation site identification), in vitro kinase/phosphatase assays, RNA-binding assay, chemokinesis assay, primary CML patient cells","journal":"Leukemia","confidence":"High","confidence_rationale":"Tier 1-2 / Moderate — MS site identification, mutagenesis with functional readouts (mRNA binding, chemokinesis), validated in patient cells","pmids":["23032722"],"is_preprint":false},{"year":2008,"finding":"TEL/PDGFRB leukemogenic tyrosine kinase increases THOC5 expression and phosphorylation; elevated THOC5 expression increases PIP3 (phosphatidylinositol 3,4,5-trisphosphate) levels and decreases apoptosis. Mass spectrometry identified the TEL/PDGFRB phosphorylation site on THOC5, which is also a target for multiple other leukemogenic tyrosine kinases.","method":"Mass spectrometry (phosphosite identification), PIP3 measurement, apoptosis assay, ectopic expression","journal":"British journal of haematology","confidence":"Medium","confidence_rationale":"Tier 2-3 / Moderate — MS phosphosite identification and functional lipid/apoptosis assays, single lab","pmids":["18373705"],"is_preprint":false},{"year":2008,"finding":"THOC5 forms a complex with the transcription factor C/EBPβ (detected by co-immunoprecipitation). Ectopic THOC5 expression mimics M-CSF-stimulated monocytic maturation and enhances protein expression of C/EBPβ, C/EBPα, PU.1, and GAB2. THOC5-induced increases in PtdInsP3 are required for elevated C/EBPβ, as PI3K inhibition abrogates this effect.","method":"Co-immunoprecipitation, ectopic expression, PI3K inhibition, PtdInsP3 measurement","journal":"Cellular signalling","confidence":"Medium","confidence_rationale":"Tier 3 / Moderate — Co-IP and functional assays, single lab, multiple methods but indirect mechanistic link","pmids":["19015024"],"is_preprint":false},{"year":2021,"finding":"THOC2 promotes stem-like properties and radioresistance of triple-negative breast cancer cells in a THOC5-dependent manner by facilitating nuclear export of SOX2 and NANOG mRNA transcripts. Silencing THOC5 decreases SOX2 and NANOG protein expression and depletes stem-like properties.","method":"siRNA knockdown of THOC2 and THOC5, xenograft tumor assays, protein expression analysis","journal":"Advanced science","confidence":"Medium","confidence_rationale":"Tier 2-3 / Moderate — genetic KD with functional phenotype and defined molecular targets, single lab","pmids":["34708581"],"is_preprint":false},{"year":2022,"finding":"THOC5 depletion results in altered 3' cleavage of >50% of mRNAs and decreases RNA polymerase II elongation rates in vivo. THOC5 is recruited to chromatin preferentially near high-density polymerase II sites. In slow polymerase II cells, chromatin-associated THOC5 interacts with CDK12 (a transcription elongation modulator), RNA helicases DDX5, DDX17, and THOC6. The CDK12-THOC5 interaction promotes CDK12 recruitment to R-loops in a THOC6-dependent manner.","method":"THOC5 depletion (siRNA/KO), in vivo transcription elongation rate measurement, ChIP-seq, co-immunoprecipitation of chromatin-associated proteins, R-loop analysis","journal":"iScience","confidence":"High","confidence_rationale":"Tier 2 / Moderate — multiple orthogonal methods (elongation rate measurement, ChIP-seq, Co-IP, R-loop assays) in single lab","pmids":["36590164"],"is_preprint":false},{"year":2024,"finding":"The cancer-associated SF3B1 K700E mutation attenuates SF3B1 interaction with THOC5, reduces THOC5 binding to a subset of mRNAs, and inhibits nuclear export of those mRNAs. Overexpression of THOC5 restores nuclear export of these mRNAs in SF3B1 K700E cells. Other cancer-associated SF3B1 mutations similarly inhibit mRNA nuclear export via this mechanism.","method":"Co-immunoprecipitation (SF3B1 K700E vs. wild-type), RNA immunoprecipitation (RIP), mRNA nuclear export assays, THOC5 overexpression rescue","journal":"Journal of biochemistry","confidence":"Medium","confidence_rationale":"Tier 2-3 / Moderate — Co-IP, RIP, and functional rescue assays, single lab","pmids":["39259498"],"is_preprint":false},{"year":2022,"finding":"THOC5 shuttles between nucleus and cytoplasm in an M-CSF signaling-dependent manner in osteoclast precursors. THOC5 binds to FICD (a proteolytic cleavage product of c-FMS receptor) and facilitates nuclear translocation of FICD. THOC5 knockdown suppresses osteoclast differentiation partly by reducing RANKL-induced FOS and NFATc1 expression.","method":"siRNA knockdown, co-immunoprecipitation (THOC5-FICD interaction), subcellular fractionation/localization, osteoclast differentiation assay","journal":"European journal of cell biology","confidence":"Medium","confidence_rationale":"Tier 2-3 / Moderate — Co-IP, localization assay, functional KD with defined molecular and cellular phenotype, single lab","pmids":["35688054"],"is_preprint":false},{"year":2016,"finding":"MPL W515L mutant receptor induces phosphorylation of THOC5 on tyrosine 225, which mediates dysregulation of MYC mRNA expression (RNA transport) and increased chemokinesis. This was demonstrated by site-directed mutagenesis showing that THOC5 Y225 phosphorylation is required for MPL W515L-mediated effects on chemokinesis and MYC expression.","method":"Proteomics (relative quantification mass spectrometry), site-directed mutagenesis (Y225), chemokinesis assay, primary CD34+ patient cells","journal":"Oncotarget","confidence":"Medium","confidence_rationale":"Tier 2-3 / Moderate — mutagenesis and functional assays with patient cell validation, single lab","pmids":["26919114"],"is_preprint":false}],"current_model":"THOC5 is a subunit of the mammalian THO/TREX mRNA export complex that functions as a selective mRNA export adaptor and 3'-processing co-factor: it binds directly to the Tap-p15 export receptor (at a site distinct from the Aly adaptor), interacts with CFIm68 and CPSF100 to regulate co-transcriptional polyadenylation site choice, recruits CDK12 to R-loops to regulate transcription elongation rate, and mediates nuclear export of a specific subset (~1% total, but >90% of inducible/immediate-early) mRNAs; its activity is regulated by phosphorylation—by c-Fms/PKC on S5/S6 (controlling nuclear-cytoplasmic localization), by Src/leukemogenic tyrosine kinases on Y225 (controlling mRNA-binding and chemokinesis), and by ATM kinase (suppressing mRNA-binding after DNA damage)—making it an essential factor for hematopoietic stem cell survival, cytokine-induced differentiation, and intestinal epithelial homeostasis."},"narrative":{"mechanistic_narrative":"THOC5 is a subunit of the mammalian THO/TREX complex that acts as a selective mRNA export adaptor coupling co-transcriptional 3'-end processing to nuclear export of a defined subset of transcripts rather than bulk mRNA [PMID:19165146, PMID:21525145]. It binds directly to a distinct, non-overlapping surface on the Ntf2-like middle domain of the Tap export receptor—allowing simultaneous Tap engagement by THOC5 and the Aly adaptor—and exhibits intrinsic RNA-binding activity within stable THO mRNPs [PMID:19165146]. Through direct interaction with the cleavage/polyadenylation machinery, THOC5 governs poly(A) site choice: it loads CFIm68 co-transcriptionally to favor distal polyadenylation sites and recruits CPSF100 to the 3'UTRs of target genes, so that loss of THOC5 yields chromatin-retained transcripts, shortened 3'UTRs, and failed export [PMID:23685434, PMID:25274738]. THOC5 is recruited to chromatin near sites of high RNA polymerase II density and, via interaction with CDK12 and THOC6, modulates polymerase II elongation rate and CDK12 recruitment to R-loops, mechanistically linking it to transcription as well as processing [PMID:36590164]. The factor is selectively required for export of inducible and immediate-early transcripts—including heat-shock, M-CSF, Wnt, and serum-responsive genes (Hsp70, Ets1, Sox9, Ascl2, Myc, and immediate-early genes)—with over 90% of serum-induced immediate-early genes failing induction upon THOC5 loss [PMID:21525145, PMID:24157873, PMID:24267292, PMID:25274738]. THOC5 activity is gated by signaling-dependent phosphorylation: PKC phosphorylates serines 5/6 adjacent to its NLS to drive nuclear-to-cytoplasmic translocation [PMID:15221008], Src-family and leukemogenic tyrosine kinases phosphorylate Y225 to control mRNA-binding and chemokinesis [PMID:23032722, PMID:26919114], and the ATM-p53 pathway suppresses its mRNA-binding after DNA damage [PMID:21937706]. Consistent with its role in inducible gene expression, conditional deletion in mice causes rapid apoptosis of hematopoietic progenitors and disrupts intestinal epithelial homeostasis, and its activity is co-opted in leukemia and breast cancer stem-like states [PMID:20051105, PMID:24267292, PMID:34708581].","teleology":[{"year":1999,"claim":"Established the first molecular handle on THOC5 as a signaling-responsive protein by showing it transiently associates with an activated receptor tyrosine kinase, raising the question of how a cytokine receptor connects to this factor.","evidence":"Co-IP and GST-Fms pulldown with deletion mutagenesis in cell systems","pmids":["10597251"],"confidence":"High","gaps":["Did not define THOC5's downstream nuclear function","Functional consequence of the transient Fms binding for differentiation unresolved at this stage"]},{"year":2004,"claim":"Answered how THOC5 subcellular distribution is controlled, showing PKC phosphorylation near the NLS shifts it from nucleus to cytoplasm and links this to differentiation signaling.","evidence":"Phosphomimetic/non-phosphorylatable S5/S6 mutants with localization and differentiation assays","pmids":["15221008"],"confidence":"High","gaps":["Did not connect localization control to a specific mRNA export function","Endogenous PKC kinase identity in vivo not pinned down"]},{"year":2006,"claim":"Provided the first link between THOC5 and RNA processing, showing it is needed for production of polyadenylated C/EBPalpha mRNA and is part of the THO complex during lineage decisions.","evidence":"Overexpression/knockdown with Northern blot, RT-PCR, and Co-IP in C2C12 cells","pmids":["16909111"],"confidence":"Medium","gaps":["Mechanism of processing/export selectivity undefined","Direct vs indirect effect on C/EBPalpha not separated"]},{"year":2008,"claim":"Defined THOC5 as a partner-import platform by showing it directly binds and chaperones THOC7 into the nucleus, clarifying THO complex assembly.","evidence":"Co-IP, domain-mapping deletion mutagenesis, and co-localization imaging","pmids":["19059247"],"confidence":"High","gaps":["Structural basis of the THOC5-THOC7 interface not resolved","Whether nuclear import of THOC7 is required for export function untested"]},{"year":2008,"claim":"Connected THOC5 to oncogenic signaling and survival, showing leukemogenic tyrosine kinases phosphorylate it to elevate PIP3 and suppress apoptosis, and that it associates with C/EBPbeta to drive myeloid maturation.","evidence":"Mass spectrometry phosphosite identification, PIP3/PtdInsP3 and apoptosis assays, Co-IP, ectopic expression","pmids":["18373705","19015024"],"confidence":"Medium","gaps":["Mechanistic link between phosphorylation, PIP3 elevation, and mRNA function unclear","Direct vs indirect C/EBPbeta interaction not fully validated"]},{"year":2009,"claim":"Resolved how THOC5 interfaces with the export machinery, demonstrating direct binding to a Tap surface distinct from Aly and selective requirement for HSP70 mRNA export but not bulk export.","evidence":"Reciprocal in vitro binding (GST pulldown), Co-IP, RNA-binding assays, and knockdown export assays","pmids":["19165146"],"confidence":"High","gaps":["Did not define the full set of THOC5-dependent transcripts","Determinants of transcript selectivity unknown"]},{"year":2010,"claim":"Established the in vivo physiological essentiality of THOC5, showing its loss triggers rapid hematopoietic progenitor apoptosis and destabilizes THO complex partner THOC1.","evidence":"Interferon-inducible conditional knockout mouse with bone marrow transplant rescue and flow cytometry","pmids":["20051105"],"confidence":"High","gaps":["Which essential target mRNAs underlie progenitor survival not identified","Cell-type specificity of dependence not mapped"]},{"year":2011,"claim":"Defined THOC5 as a selective export factor for ~10 spliced transcripts and showed Hsp70 export is THOC5-dependent only under heat stress, framing it as a stress/inducible-mRNA export factor.","evidence":"Cre-lox conditional KO MEFs with cytoplasmic transcriptome analysis and RIP","pmids":["21525145"],"confidence":"High","gaps":["Sequence/structural features marking THOC5-dependent transcripts unknown","Stage at which selectivity is imposed not defined"]},{"year":2011,"claim":"Answered how DNA damage modulates THOC5, showing the ATM-p53 pathway suppresses its mRNA-binding via its C-terminal domain, linking export to the damage response.","evidence":"RIP, ATM inhibitor (KU55933), ATM/p53 siRNA epistasis, and C-terminal/PEST mutants","pmids":["21937706"],"confidence":"High","gaps":["Whether ATM directly phosphorylates THOC5 not established","The C-terminal regulatory residues not pinpointed"]},{"year":2012,"claim":"Identified Y225 as a tyrosine-kinase-controlled switch for THOC5 mRNA-binding and cell motility, dysregulated in CML and drug-targetable.","evidence":"MS phosphosite mapping, Y225 mutagenesis, in vitro kinase/phosphatase (Src/CD45) assays, chemokinesis assays, primary CML cells","pmids":["23032722"],"confidence":"High","gaps":["How Y225 phosphorylation alters RNA contacts mechanistically unclear","Full set of Y225-dependent transcripts not enumerated"]},{"year":2013,"claim":"Mechanistically united THOC5 with co-transcriptional 3'-end processing and inducible gene programs, showing it loads CFIm68 to set poly(A) site choice and is needed for processing/export of M-CSF and Wnt target mRNAs.","evidence":"Co-IP, ChIP-seq, microarray, inducible conditional KO, RIP across multiple studies","pmids":["23685434","24157873","24267292"],"confidence":"High","gaps":["Direct vs bridged nature of THOC5-CFIm68 contact not crystallographically defined","How processing defect is mechanistically coupled to export block not fully separated"]},{"year":2014,"claim":"Extended the processing role to immediate-early gene induction, showing THOC5 recruits CPSF100 to target 3'UTRs and is required for serum induction of >90% of immediate-early genes.","evidence":"MS interactome with THOC5 bait, chromatin association assays, transcriptomics, serum stimulation with knockdown","pmids":["25274738"],"confidence":"High","gaps":["Order of CFIm68 vs CPSF100 recruitment not resolved","Determinants targeting THOC5 to IEG loci unknown"]},{"year":2016,"claim":"Generalized the Y225 switch to other leukemogenic receptors, showing MPL W515L drives Y225 phosphorylation to dysregulate MYC transport and chemokinesis.","evidence":"Quantitative proteomics, Y225 mutagenesis, chemokinesis assays, primary CD34+ patient cells","pmids":["26919114"],"confidence":"Medium","gaps":["Direct kinase responsible for Y225 in this context not confirmed","Mechanism linking Y225 to MYC mRNA selectivity unclear"]},{"year":2021,"claim":"Implicated THOC5 in cancer stemness, showing it is required for THOC2-dependent export of SOX2/NANOG mRNAs and radioresistance in triple-negative breast cancer.","evidence":"siRNA knockdown, xenograft assays, protein expression analysis","pmids":["34708581"],"confidence":"Medium","gaps":["Direct THOC5 binding to SOX2/NANOG transcripts not shown here","Whether processing or export step is rate-limiting undefined"]},{"year":2022,"claim":"Revealed a transcription-elongation arm of THOC5 function, showing chromatin-associated THOC5 interacts with CDK12, DDX5/17, and THOC6 to set polymerase II elongation rate and recruit CDK12 to R-loops.","evidence":"Depletion plus in vivo elongation rate measurement, ChIP-seq, chromatin Co-IP, R-loop analysis; plus M-CSF-dependent shuttling and FICD binding in osteoclast precursors","pmids":["36590164","35688054"],"confidence":"High","gaps":["Causal hierarchy between elongation control, R-loop resolution, and processing not resolved","Structural basis of CDK12-THOC5-THOC6 assembly unknown"]},{"year":2024,"claim":"Linked THOC5 to oncogenic splicing-factor mutation, showing SF3B1 K700E weakens SF3B1-THOC5 interaction and impairs export of THOC5-bound mRNAs, rescuable by THOC5 overexpression.","evidence":"Co-IP (mutant vs WT SF3B1), RIP, nuclear export assays, THOC5 overexpression rescue","pmids":["39259498"],"confidence":"Medium","gaps":["Whether SF3B1-THOC5 contact is direct not established","Identity of the affected transcript set incompletely defined"]},{"year":null,"claim":"What molecular features mark a transcript as THOC5-dependent, and how phosphorylation, processing, elongation, and export selectivity are mechanistically integrated, remains unresolved.","evidence":"","pmids":[],"confidence":"Medium","gaps":["No structural model of THOC5 in the THO/TREX complex with its processing/export partners","Cis-determinants of THOC5 target selectivity unknown","Causal ordering of elongation control vs 3'-processing vs export not established"]}],"mechanism_profile":{"molecular_activity":[{"term_id":"GO:0003723","term_label":"RNA binding","supporting_discovery_ids":[0,6,8,11,12]},{"term_id":"GO:0060090","term_label":"molecular adaptor activity","supporting_discovery_ids":[0,7,10]},{"term_id":"GO:0140098","term_label":"catalytic activity, acting on RNA","supporting_discovery_ids":[7,10,16]}],"localization":[{"term_id":"GO:0005654","term_label":"nucleoplasm","supporting_discovery_ids":[2,8]},{"term_id":"GO:0005634","term_label":"nucleus","supporting_discovery_ids":[0,2,3,8]},{"term_id":"GO:0005829","term_label":"cytosol","supporting_discovery_ids":[2,8,18]},{"term_id":"GO:0000228","term_label":"nuclear chromosome","supporting_discovery_ids":[8,10,16]}],"pathway":[{"term_id":"R-HSA-8953854","term_label":"Metabolism of RNA","supporting_discovery_ids":[0,6,7,10]},{"term_id":"R-HSA-74160","term_label":"Gene expression (Transcription)","supporting_discovery_ids":[7,10,16]},{"term_id":"R-HSA-9609507","term_label":"Protein localization","supporting_discovery_ids":[0,6,17]},{"term_id":"R-HSA-8953897","term_label":"Cellular responses to stimuli","supporting_discovery_ids":[6,11]}],"complexes":["THO/TREX complex"],"partners":["TAP/NXF1","ALYREF","THOC1","THOC7","CPSF6/CFIM68","CPSF2/CPSF100","CDK12","SF3B1"],"other_free_text":[]}},"prefetch_data":{"uniprot":{"accession":"Q13769","full_name":"THO complex subunit 5","aliases":["Functional spliceosome-associated protein 79","fSAP79","NF2/meningioma region protein pK1.3","Placental protein 39.2","PP39.2","hTREX90"],"length_aa":683,"mass_kda":78.5,"function":"Component of the THO subcomplex of the TREX complex which is thought to couple mRNA transcription, processing and nuclear export, and which specifically associates with spliced mRNA and not with unspliced pre-mRNA (PubMed:15833825, PubMed:15998806, PubMed:17190602). Plays a key structural role in the oligomerization of the THO-DDX39B complex (PubMed:33191911). TREX is recruited to spliced mRNAs by a transcription-independent mechanism, binds to mRNA upstream of the exon-junction complex (EJC) and is recruited in a splicing- and cap-dependent manner to a region near the 5' end of the mRNA where it functions in mRNA export to the cytoplasm via the TAP/NXF1 pathway (PubMed:15833825, PubMed:15998806, PubMed:17190602). THOC5 in conjunction with ALYREF/THOC4 functions in NXF1-NXT1 mediated nuclear export of HSP70 mRNA; both proteins enhance the RNA binding activity of NXF1 and are required for NXF1 localization to the nuclear rim. Involved in transcription elongation and genome stability (PubMed:18974867). Involved in alternative polyadenylation site choice by recruiting CPSF6 to 5' region of target genes; probably mediates association of the TREX and CFIm complexes (PubMed:23685434) Regulates the expression of myeloid transcription factors CEBPA, CEBPB and GAB2 by enhancing the levels of phosphatidylinositol 3,4,5-trisphosphate. May be involved in the differentiation of granulocytes and adipocytes. Essential for hematopoietic primitive cell survival and plays an integral role in monocytic development (Microbial infection) The TREX complex is essential for the export of Kaposi's sarcoma-associated herpesvirus (KSHV) intronless mRNAs and infectious virus production","subcellular_location":"Nucleus; Cytoplasm","url":"https://www.uniprot.org/uniprotkb/Q13769/entry"},"depmap":{"release":"DepMap","has_data":true,"is_common_essential":true,"resolved_as":"","url":"https://depmap.org/portal/gene/THOC5","classification":"Common Essential","n_dependent_lines":1184,"n_total_lines":1208,"dependency_fraction":0.9801324503311258},"opencell":{"profiled":false,"resolved_as":"","ensg_id":"","cell_line_id":"","localizations":[],"interactors":[{"gene":"CPSF6","stoichiometry":0.2},{"gene":"DDX39B","stoichiometry":0.2},{"gene":"RBM33","stoichiometry":0.2},{"gene":"RBM39","stoichiometry":0.2},{"gene":"SF3A1","stoichiometry":0.2},{"gene":"SNRPA","stoichiometry":0.2},{"gene":"SNRPB","stoichiometry":0.2},{"gene":"SNRPC","stoichiometry":0.2},{"gene":"SSRP1","stoichiometry":0.2},{"gene":"TOP1","stoichiometry":0.2}],"url":"https://opencell.sf.czbiohub.org/search/THOC5","total_profiled":1310},"omim":[{"mim_id":"615403","title":"THO COMPLEX, SUBUNIT 6; THOC6","url":"https://www.omim.org/entry/615403"},{"mim_id":"612733","title":"THO COMPLEX, SUBUNIT 5; THOC5","url":"https://www.omim.org/entry/612733"},{"mim_id":"611965","title":"THO COMPLEX, SUBUNIT 7; THOC7","url":"https://www.omim.org/entry/611965"},{"mim_id":"606930","title":"THO COMPLEX, SUBUNIT 1; THOC1","url":"https://www.omim.org/entry/606930"},{"mim_id":"606929","title":"THO COMPLEX, SUBUNIT 3; THOC3","url":"https://www.omim.org/entry/606929"}],"hpa":{"profiled":true,"resolved_as":"","reliability":"Supported","locations":[{"location":"Nucleoplasm","reliability":"Supported"}],"tissue_specificity":"Low tissue specificity","tissue_distribution":"Detected in all","driving_tissues":[],"url":"https://www.proteinatlas.org/search/THOC5"},"hgnc":{"alias_symbol":["PK1.3","KIAA0983","Fmip","fSAP79"],"prev_symbol":["C22orf19"]},"alphafold":{"accession":"Q13769","domains":[{"cath_id":"-","chopping":"257-301_332-482","consensus_level":"high","plddt":85.4265,"start":257,"end":482},{"cath_id":"-","chopping":"500-641_650-680","consensus_level":"high","plddt":90.3867,"start":500,"end":680},{"cath_id":"1.20.58","chopping":"40-148","consensus_level":"high","plddt":90.3619,"start":40,"end":148},{"cath_id":"1.20.5","chopping":"158-249","consensus_level":"medium","plddt":84.0807,"start":158,"end":249}],"viewer_url":"https://alphafold.ebi.ac.uk/entry/Q13769","model_url":"https://alphafold.ebi.ac.uk/files/AF-Q13769-F1-model_v6.cif","pae_url":"https://alphafold.ebi.ac.uk/files/AF-Q13769-F1-predicted_aligned_error_v6.png","plddt_mean":82.94},"mouse_models":{"mgi_url":"https://www.informatics.jax.org/marker/summary?nomen=THOC5","jax_strain_url":"https://www.jax.org/strain/search?query=THOC5"},"sequence":{"accession":"Q13769","fasta_url":"https://rest.uniprot.org/uniprotkb/Q13769.fasta","uniprot_url":"https://www.uniprot.org/uniprotkb/Q13769/entry","alphafold_viewer_url":"https://alphafold.ebi.ac.uk/entry/Q13769"}},"corpus_meta":[{"pmid":"19165146","id":"PMC_19165146","title":"Adaptor Aly and co-adaptor Thoc5 function in the Tap-p15-mediated nuclear export of HSP70 mRNA.","date":"2009","source":"The EMBO journal","url":"https://pubmed.ncbi.nlm.nih.gov/19165146","citation_count":118,"is_preprint":false},{"pmid":"20051105","id":"PMC_20051105","title":"THOC5/FMIP, an mRNA export TREX complex protein, is essential for hematopoietic primitive cell survival in vivo.","date":"2010","source":"BMC biology","url":"https://pubmed.ncbi.nlm.nih.gov/20051105","citation_count":99,"is_preprint":false},{"pmid":"21525145","id":"PMC_21525145","title":"Identification of mRNAs that are spliced but not exported to the cytoplasm in the absence of THOC5 in mouse embryo fibroblasts.","date":"2011","source":"RNA (New York, N.Y.)","url":"https://pubmed.ncbi.nlm.nih.gov/21525145","citation_count":56,"is_preprint":false},{"pmid":"23685434","id":"PMC_23685434","title":"Human TREX component Thoc5 affects alternative polyadenylation site choice by recruiting mammalian cleavage factor I.","date":"2013","source":"Nucleic acids research","url":"https://pubmed.ncbi.nlm.nih.gov/23685434","citation_count":49,"is_preprint":false},{"pmid":"34708581","id":"PMC_34708581","title":"THOC2 and THOC5 Regulate Stemness and Radioresistance in Triple-Negative Breast Cancer.","date":"2021","source":"Advanced science (Weinheim, Baden-Wurttemberg, Germany)","url":"https://pubmed.ncbi.nlm.nih.gov/34708581","citation_count":48,"is_preprint":false},{"pmid":"10597251","id":"PMC_10597251","title":"FMIP, a novel Fms-interacting protein, affects granulocyte/macrophage differentiation.","date":"1999","source":"Oncogene","url":"https://pubmed.ncbi.nlm.nih.gov/10597251","citation_count":42,"is_preprint":false},{"pmid":"25274738","id":"PMC_25274738","title":"THOC5 controls 3'end-processing of immediate early genes via interaction with polyadenylation specific factor 100 (CPSF100).","date":"2014","source":"Nucleic acids research","url":"https://pubmed.ncbi.nlm.nih.gov/25274738","citation_count":33,"is_preprint":false},{"pmid":"15221008","id":"PMC_15221008","title":"The M-CSF receptor substrate and interacting protein FMIP is governed in its subcellular localization by protein kinase C-mediated phosphorylation, and thereby potentiates M-CSF-mediated differentiation.","date":"2004","source":"Oncogene","url":"https://pubmed.ncbi.nlm.nih.gov/15221008","citation_count":33,"is_preprint":false},{"pmid":"24410813","id":"PMC_24410813","title":"THOC5, a member of the mRNA export complex: a novel link between mRNA export machinery and signal transduction pathways in cell proliferation and differentiation.","date":"2014","source":"Cell communication and signaling : CCS","url":"https://pubmed.ncbi.nlm.nih.gov/24410813","citation_count":30,"is_preprint":false},{"pmid":"24157873","id":"PMC_24157873","title":"Transcriptional regulation of immediate-early gene response by THOC5, a member of mRNA export complex, contributes to the M-CSF-induced macrophage differentiation.","date":"2013","source":"Cell death & disease","url":"https://pubmed.ncbi.nlm.nih.gov/24157873","citation_count":30,"is_preprint":false},{"pmid":"16909111","id":"PMC_16909111","title":"FMIP controls the adipocyte lineage commitment of C2C12 cells by downmodulation of C/EBP alpha.","date":"2006","source":"Oncogene","url":"https://pubmed.ncbi.nlm.nih.gov/16909111","citation_count":28,"is_preprint":false},{"pmid":"26549021","id":"PMC_26549021","title":"Depletion of three combined THOC5 mRNA export protein target genes synergistically induces human hepatocellular carcinoma cell death.","date":"2015","source":"Oncogene","url":"https://pubmed.ncbi.nlm.nih.gov/26549021","citation_count":23,"is_preprint":false},{"pmid":"24267292","id":"PMC_24267292","title":"THOC5, a member of the mRNA export complex, contributes to processing of a subset of wingless/integrated (Wnt) target mRNAs and integrity of the gut epithelial barrier.","date":"2013","source":"BMC cell biology","url":"https://pubmed.ncbi.nlm.nih.gov/24267292","citation_count":23,"is_preprint":false},{"pmid":"23032722","id":"PMC_23032722","title":"A pathway from leukemogenic oncogenes and stem cell chemokines to RNA processing via THOC5.","date":"2012","source":"Leukemia","url":"https://pubmed.ncbi.nlm.nih.gov/23032722","citation_count":19,"is_preprint":false},{"pmid":"19059247","id":"PMC_19059247","title":"Nuclear localization of the pre-mRNA associating protein THOC7 depends upon its direct interaction with Fms tyrosine kinase interacting protein (FMIP).","date":"2008","source":"FEBS letters","url":"https://pubmed.ncbi.nlm.nih.gov/19059247","citation_count":17,"is_preprint":false},{"pmid":"18373705","id":"PMC_18373705","title":"THOC5 spliceosome protein: a target for leukaemogenic tyrosine kinases that affects inositol lipid turnover.","date":"2008","source":"British journal of haematology","url":"https://pubmed.ncbi.nlm.nih.gov/18373705","citation_count":16,"is_preprint":false},{"pmid":"21937706","id":"PMC_21937706","title":"An ataxia-telangiectasia-mutated (ATM) kinase mediated response to DNA damage down-regulates the mRNA-binding potential of THOC5.","date":"2011","source":"RNA (New York, N.Y.)","url":"https://pubmed.ncbi.nlm.nih.gov/21937706","citation_count":16,"is_preprint":false},{"pmid":"19015024","id":"PMC_19015024","title":"THOC5 couples M-CSF receptor signaling to transcription factor expression.","date":"2008","source":"Cellular signalling","url":"https://pubmed.ncbi.nlm.nih.gov/19015024","citation_count":15,"is_preprint":false},{"pmid":"26828015","id":"PMC_26828015","title":"mRNA export protein THOC5 as a tool for identification of target genes for cancer therapy.","date":"2016","source":"Cancer letters","url":"https://pubmed.ncbi.nlm.nih.gov/26828015","citation_count":14,"is_preprint":false},{"pmid":"36590164","id":"PMC_36590164","title":"THOC5 complexes with DDX5, DDX17, and CDK12 to regulate R loop structures and transcription elongation rate.","date":"2022","source":"iScience","url":"https://pubmed.ncbi.nlm.nih.gov/36590164","citation_count":14,"is_preprint":false},{"pmid":"24023261","id":"PMC_24023261","title":"THOC5: a novel gene involved in HDL-cholesterol metabolism.","date":"2013","source":"Journal of lipid research","url":"https://pubmed.ncbi.nlm.nih.gov/24023261","citation_count":12,"is_preprint":false},{"pmid":"38519939","id":"PMC_38519939","title":"Acylcarnitines promote gallbladder cancer metastasis through lncBCL2L11-THOC5-JNK axis.","date":"2024","source":"Journal of translational medicine","url":"https://pubmed.ncbi.nlm.nih.gov/38519939","citation_count":10,"is_preprint":false},{"pmid":"26919114","id":"PMC_26919114","title":"MPL W515L expression induces TGFβ secretion and leads to an increase in chemokinesis via phosphorylation of THOC5.","date":"2016","source":"Oncotarget","url":"https://pubmed.ncbi.nlm.nih.gov/26919114","citation_count":7,"is_preprint":false},{"pmid":"38583499","id":"PMC_38583499","title":"Resveratrol regulates Thoc5 to improve maternal immune activation-induced autism-like behaviors in adult mouse offspring.","date":"2024","source":"The Journal of nutritional biochemistry","url":"https://pubmed.ncbi.nlm.nih.gov/38583499","citation_count":5,"is_preprint":false},{"pmid":"31098739","id":"PMC_31098739","title":"Colla corii asini might upregulate ZNF471 and THOC5 by KRAB domain-containing zinc-finger protein pathway and THO complex subunit 5 pathway to improve anemia of pregnant women with β-thalassemia.","date":"2019","source":"Annals of hematology","url":"https://pubmed.ncbi.nlm.nih.gov/31098739","citation_count":5,"is_preprint":false},{"pmid":"39259498","id":"PMC_39259498","title":"Cancer-associated SF3B1 mutations inhibit mRNA nuclear export by disrupting SF3B1-THOC5 interactions.","date":"2024","source":"Journal of biochemistry","url":"https://pubmed.ncbi.nlm.nih.gov/39259498","citation_count":2,"is_preprint":false},{"pmid":"31402763","id":"PMC_31402763","title":"Polymorphism of the THOC5 of the transcription/export multiprotein complex and its correlation with the lipid and metabolic profile in middle-aged women.","date":"2019","source":"Gynecological endocrinology : the official journal of the International Society of Gynecological Endocrinology","url":"https://pubmed.ncbi.nlm.nih.gov/31402763","citation_count":2,"is_preprint":false},{"pmid":"35688054","id":"PMC_35688054","title":"THOC5 regulates human osteoclastogenesis.","date":"2022","source":"European journal of cell biology","url":"https://pubmed.ncbi.nlm.nih.gov/35688054","citation_count":1,"is_preprint":false},{"pmid":"40901498","id":"PMC_40901498","title":"Elevated THOC5 expression in liver cancer and its implications for tumor progression and therapeutic response.","date":"2025","source":"Frontiers in medicine","url":"https://pubmed.ncbi.nlm.nih.gov/40901498","citation_count":1,"is_preprint":false},{"pmid":"41024185","id":"PMC_41024185","title":"Long non-coding RNA HMGCR suppresses vascular remodeling in streptozotocin-induced type 1 diabetic rats via interaction with THOC5.","date":"2025","source":"European journal of medical research","url":"https://pubmed.ncbi.nlm.nih.gov/41024185","citation_count":1,"is_preprint":false},{"pmid":"40107550","id":"PMC_40107550","title":"Targeting mRNA export complex macromolecules THO subunits (Thoc2 and Thoc5) for somatic cell reprograming.","date":"2025","source":"International journal of biological macromolecules","url":"https://pubmed.ncbi.nlm.nih.gov/40107550","citation_count":0,"is_preprint":false}],"cost":{"stage1":{"model":"claude-sonnet-4-6","input_tokens":18018,"output_tokens":5773,"usd":0.070324,"stage1_stop_reason":"end_turn"},"stage2":{"model":"claude-opus-4-8","input_tokens":14176,"output_tokens":5278,"usd":0.101415,"stage2_stop_reason":"end_turn"},"total_usd":0.171739,"stage1_batch_id":"msgbatch_017qqVz33Ga63SCDwzb35XPb","stage2_batch_id":"msgbatch_01Scr2Ei9x4HJMiRGxwrmvLK","note":"batch pricing = 50% of standard"},"stage1_raw":"```json\n{\n  \"discoveries\": [\n    {\n      \"year\": 2009,\n      \"finding\": \"THOC5 binds to a distinct, non-overlapping surface on the middle (Ntf2-like) domain of the Tap export receptor, allowing simultaneous binding of both THOC5 and the adaptor protein Aly to Tap-p15. THOC5 exhibits in vitro RNA-binding activity and associates with HSP70 mRNPs in vivo as a component of the stable THO complex. Nuclear export of HSP70 mRNA specifically requires both THOC5 and Aly, but THOC5 is not required for bulk mRNA export.\",\n      \"method\": \"Co-immunoprecipitation, in vitro binding assays (GST pulldown), RNA-binding assays, in vivo mRNA export assays with knockdown\",\n      \"journal\": \"The EMBO journal\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — reciprocal binding assays (in vitro and in vivo), multiple orthogonal methods, functional export assay with knockdown\",\n      \"pmids\": [\"19165146\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 1999,\n      \"finding\": \"THOC5/FMIP (MW ~78 kDa) binds transiently via its N-terminal 144 residues to the cytoplasmic domain of activated (ligand-stimulated) c-Fms tyrosine kinase receptor. Binding is followed by rapid tyrosine phosphorylation of FMIP within the binding domain, which drastically reduces its association with Fms. No binding was observed with the cytoplasmic domains of c-Kit, TrkA, c-Met, or the insulin receptor.\",\n      \"method\": \"Co-immunoprecipitation, GST-Fms fusion protein pulldown, deletion mutagenesis\",\n      \"journal\": \"Oncogene\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — reciprocal Co-IP and GST pulldown with deletion mutagenesis in single study\",\n      \"pmids\": [\"10597251\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2004,\n      \"finding\": \"THOC5/FMIP is phosphorylated by protein kinase C (PKC) on serines 5 and 6, adjacent to its nuclear localization signal (NLS). This NLS is essential for predominantly nuclear localization. PKC-mediated phosphorylation on S5/S6 causes translocation of THOC5 from nucleus to cytosol. Phosphomimetic mutations (SS5,6EE) promoted cytoplasmic localization and enhanced M-CSF-mediated survival/differentiation, while non-phosphorylatable mutant (SS5,6AA) remained nuclear even in the presence of activated PKCα.\",\n      \"method\": \"Site-directed mutagenesis (phosphomimetic and non-phosphorylatable mutants), subcellular fractionation/localization imaging, functional differentiation assay\",\n      \"journal\": \"Oncogene\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1-2 / Moderate — mutagenesis with functional validation and localization assays, single lab but multiple orthogonal methods\",\n      \"pmids\": [\"15221008\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2008,\n      \"finding\": \"THOC7 lacks a typical nuclear localization signal (NLS) and resides mainly in the cytoplasm on its own, but directly binds to the N-terminal portion (residues 1-199) of THOC5/FMIP via THOC7 residues 50-137. This interaction is required for THOC5-dependent nuclear transport of THOC7: in the presence of THOC5, THOC7 is transported into the nucleus; a THOC7 mutant lacking the FMIP-binding site fails to co-localize with FMIP.\",\n      \"method\": \"Co-immunoprecipitation, deletion mutagenesis, subcellular localization imaging (co-transfection/co-localization)\",\n      \"journal\": \"FEBS letters\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — domain mapping by deletion mutagenesis plus functional localization assay, single lab\",\n      \"pmids\": [\"19059247\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2006,\n      \"finding\": \"THOC5/FMIP overexpression in C2C12 cells prevents adipocyte differentiation and promotes granulocyte/muscle phenotype, while FMIP knockdown promotes adipocyte lineage commitment and impairs muscle differentiation. Mechanistically, FMIP-overexpressing cells lack polyadenylated C/EBPα mRNA but retain C/EBPα pre-mRNA (detected by Northern blot and RT-PCR), implicating FMIP in RNA processing/export of C/EBPα. THOC1 co-precipitates with FMIP, placing it in the THO complex in this context.\",\n      \"method\": \"Ectopic expression and siRNA knockdown, Northern blot, RT-PCR, co-immunoprecipitation\",\n      \"journal\": \"Oncogene\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2-3 / Moderate — multiple methods (overexpression, KD, RNA analysis, Co-IP) in single lab\",\n      \"pmids\": [\"16909111\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2010,\n      \"finding\": \"Conditional knockout of THOC5 in mice leads to rapid apoptosis of hematopoietic progenitor cells (committed myeloid progenitors and long-term reconstituting cells) within days, demonstrating THOC5 is essential for hematopoietic primitive cell survival in vivo. Mechanistically, THOC5 depletion causes down-regulation of its direct interacting partner THOC1, potentially disrupting THO complex function.\",\n      \"method\": \"Interferon-inducible conditional knockout mouse, bone marrow transplantation rescue, flow cytometry, histology\",\n      \"journal\": \"BMC biology\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — clean conditional KO with defined cellular phenotype, rescue experiment, and mechanistic link to THOC1\",\n      \"pmids\": [\"20051105\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2011,\n      \"finding\": \"THOC5 is required for export of a specific subset (~10 identified) of mRNAs (including HoxB3, CBX2); these mRNAs are spliced but not exported to the cytoplasm in THOC5-depleted MEF cells and co-purify with THOC5. Hsp70 mRNA export is specifically dependent on THOC5 under heat shock (42°C) but not under normal conditions (37°C), indicating THOC5 is required for stress-induced mRNA export rather than basal export.\",\n      \"method\": \"Conditional knockout (Cre-lox MEF cells), transcriptome analysis of cytoplasmic RNA, RNA co-immunoprecipitation (RIP)\",\n      \"journal\": \"RNA (New York, N.Y.)\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — clean genetic KO with transcriptome and RIP validation, multiple orthogonal methods\",\n      \"pmids\": [\"21525145\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2013,\n      \"finding\": \"THOC5 physically interacts with CFIm68 (large subunit of mammalian cleavage factor I involved in polyadenylation site choice). Most likely via direct Thoc5–CFIm68 interaction. THOC5 depletion selectively attenuates expression of mRNAs polyadenylated at distal polyadenylation sites (phenocopying CFIm68 depletion) and globally reduces CFIm68 association with the 5' regions of genes (by ChIP-seq), indicating THOC5 controls polyadenylation site choice by co-transcriptional loading of CFIm68.\",\n      \"method\": \"Co-immunoprecipitation (antibodies against different TREX components), microarray, ChIP-seq, siRNA knockdown\",\n      \"journal\": \"Nucleic acids research\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — Co-IP, functional transcriptomics, and ChIP-seq in single lab with multiple orthogonal methods\",\n      \"pmids\": [\"23685434\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2013,\n      \"finding\": \"THOC5 is localized in nuclear speckles and translocates from nucleus to cytoplasm during M-CSF-induced macrophage differentiation. THOC5 is required for processing/export of a subset of M-CSF-inducible mRNAs (including Ets1); depletion causes accumulation of unspliced Ets1 mRNA in the nucleus. THOC5 is recruited to chromatin at the Ets1 gene locus and binds both unspliced and spliced Ets1 transcripts.\",\n      \"method\": \"Immunofluorescence/subcellular localization, tamoxifen-inducible conditional KO, transcriptome analysis, chromatin immunoprecipitation (ChIP), RNA immunoprecipitation (RIP)\",\n      \"journal\": \"Cell death & disease\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — clean genetic KO with multiple orthogonal methods (localization, transcriptomics, ChIP, RIP) in single lab\",\n      \"pmids\": [\"24157873\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2013,\n      \"finding\": \"THOC5 is required for processing and export of a subset of Wnt target mRNAs (Sox9 and Ascl2, but not Fn1) in intestinal epithelium; these mRNAs co-purify with THOC5 by RIP. THOC5 is also required for expression of the Toll-like receptor-inducible gene COX2/Ptgs2, whose transcript is a THOC5 target mRNA. THOC5 deficiency disrupts gut epithelial differentiation and self-renewal, causing bacterial translocation and sepsis in mice.\",\n      \"method\": \"Tamoxifen-inducible conditional knockout mouse, RNA co-immunoprecipitation (RIP), transcriptome analysis, histopathology\",\n      \"journal\": \"BMC cell biology\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — clean genetic KO, RIP validation, multiple orthogonal methods in single lab\",\n      \"pmids\": [\"24267292\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2014,\n      \"finding\": \"THOC5 forms a complex with polyadenylation-specific factor 100 (CPSF100) upon serum stimulation. THOC5 is required for recruitment of CPSF100 to the 3'UTR of THOC5 target genes (including Id1, Id3, Wnt11, Myc, Smad7). Without THOC5, a subset of IEG transcripts fail to be released from chromatin or are released with shortened 3'UTRs and impaired nuclear export. Over 90% of immediate-early genes fail to be induced by serum in THOC5-depleted cells.\",\n      \"method\": \"Interactome analysis (THOC5 as bait/MS), chromatin association assays, transcriptome analysis, serum stimulation experiments with siRNA knockdown\",\n      \"journal\": \"Nucleic acids research\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — MS-based interactome, chromatin fractionation, transcriptomics with multiple orthogonal methods in single lab\",\n      \"pmids\": [\"25274738\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2011,\n      \"finding\": \"ATM kinase pathway regulates THOC5 mRNA-binding activity in response to DNA damage. DNA damage decreases cytoplasmic levels of THOC5-dependent mRNAs and impairs THOC5/mRNA complex formation. The C-terminal domain of THOC5 (not phosphorylation at S307/312/314 in the PEST domain) is required for this regulatory response. ATM kinase inhibitor (KU55933) or siRNA against ATM or p53 restores THOC5-dependent mRNA export after DNA damage, indicating the ATM-p53 pathway suppresses THOC5 mRNA-binding ability.\",\n      \"method\": \"Site-directed mutagenesis (S307/312/314A and C-terminal deletion mutants), RNA immunoprecipitation (RIP), ATM kinase inhibitor treatment, siRNA knockdown of ATM and p53\",\n      \"journal\": \"RNA (New York, N.Y.)\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1-2 / Moderate — mutagenesis, RIP, and pharmacological/genetic pathway epistasis in single lab with multiple orthogonal methods\",\n      \"pmids\": [\"21937706\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2012,\n      \"finding\": \"THOC5 phosphorylation on tyrosine 225 is mediated by Src PTK and reversed by CD45 protein tyrosine phosphatase, and is elevated in CML stem cells. This Y225 phosphorylation specifically governs THOC5 mRNA-binding activity (site-directed mutagenesis of Y225 modulates motile response to CXCL12). CXCL12 chemokine stimulation also induces THOC5 Y225 phosphorylation. THOC5 Y225 phosphorylation is sensitive to frontline CML drugs (imatinib).\",\n      \"method\": \"Site-directed mutagenesis (Y225), mass spectrometry (phosphorylation site identification), in vitro kinase/phosphatase assays, RNA-binding assay, chemokinesis assay, primary CML patient cells\",\n      \"journal\": \"Leukemia\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1-2 / Moderate — MS site identification, mutagenesis with functional readouts (mRNA binding, chemokinesis), validated in patient cells\",\n      \"pmids\": [\"23032722\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2008,\n      \"finding\": \"TEL/PDGFRB leukemogenic tyrosine kinase increases THOC5 expression and phosphorylation; elevated THOC5 expression increases PIP3 (phosphatidylinositol 3,4,5-trisphosphate) levels and decreases apoptosis. Mass spectrometry identified the TEL/PDGFRB phosphorylation site on THOC5, which is also a target for multiple other leukemogenic tyrosine kinases.\",\n      \"method\": \"Mass spectrometry (phosphosite identification), PIP3 measurement, apoptosis assay, ectopic expression\",\n      \"journal\": \"British journal of haematology\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2-3 / Moderate — MS phosphosite identification and functional lipid/apoptosis assays, single lab\",\n      \"pmids\": [\"18373705\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2008,\n      \"finding\": \"THOC5 forms a complex with the transcription factor C/EBPβ (detected by co-immunoprecipitation). Ectopic THOC5 expression mimics M-CSF-stimulated monocytic maturation and enhances protein expression of C/EBPβ, C/EBPα, PU.1, and GAB2. THOC5-induced increases in PtdInsP3 are required for elevated C/EBPβ, as PI3K inhibition abrogates this effect.\",\n      \"method\": \"Co-immunoprecipitation, ectopic expression, PI3K inhibition, PtdInsP3 measurement\",\n      \"journal\": \"Cellular signalling\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 3 / Moderate — Co-IP and functional assays, single lab, multiple methods but indirect mechanistic link\",\n      \"pmids\": [\"19015024\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2021,\n      \"finding\": \"THOC2 promotes stem-like properties and radioresistance of triple-negative breast cancer cells in a THOC5-dependent manner by facilitating nuclear export of SOX2 and NANOG mRNA transcripts. Silencing THOC5 decreases SOX2 and NANOG protein expression and depletes stem-like properties.\",\n      \"method\": \"siRNA knockdown of THOC2 and THOC5, xenograft tumor assays, protein expression analysis\",\n      \"journal\": \"Advanced science\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2-3 / Moderate — genetic KD with functional phenotype and defined molecular targets, single lab\",\n      \"pmids\": [\"34708581\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2022,\n      \"finding\": \"THOC5 depletion results in altered 3' cleavage of >50% of mRNAs and decreases RNA polymerase II elongation rates in vivo. THOC5 is recruited to chromatin preferentially near high-density polymerase II sites. In slow polymerase II cells, chromatin-associated THOC5 interacts with CDK12 (a transcription elongation modulator), RNA helicases DDX5, DDX17, and THOC6. The CDK12-THOC5 interaction promotes CDK12 recruitment to R-loops in a THOC6-dependent manner.\",\n      \"method\": \"THOC5 depletion (siRNA/KO), in vivo transcription elongation rate measurement, ChIP-seq, co-immunoprecipitation of chromatin-associated proteins, R-loop analysis\",\n      \"journal\": \"iScience\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — multiple orthogonal methods (elongation rate measurement, ChIP-seq, Co-IP, R-loop assays) in single lab\",\n      \"pmids\": [\"36590164\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2024,\n      \"finding\": \"The cancer-associated SF3B1 K700E mutation attenuates SF3B1 interaction with THOC5, reduces THOC5 binding to a subset of mRNAs, and inhibits nuclear export of those mRNAs. Overexpression of THOC5 restores nuclear export of these mRNAs in SF3B1 K700E cells. Other cancer-associated SF3B1 mutations similarly inhibit mRNA nuclear export via this mechanism.\",\n      \"method\": \"Co-immunoprecipitation (SF3B1 K700E vs. wild-type), RNA immunoprecipitation (RIP), mRNA nuclear export assays, THOC5 overexpression rescue\",\n      \"journal\": \"Journal of biochemistry\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2-3 / Moderate — Co-IP, RIP, and functional rescue assays, single lab\",\n      \"pmids\": [\"39259498\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2022,\n      \"finding\": \"THOC5 shuttles between nucleus and cytoplasm in an M-CSF signaling-dependent manner in osteoclast precursors. THOC5 binds to FICD (a proteolytic cleavage product of c-FMS receptor) and facilitates nuclear translocation of FICD. THOC5 knockdown suppresses osteoclast differentiation partly by reducing RANKL-induced FOS and NFATc1 expression.\",\n      \"method\": \"siRNA knockdown, co-immunoprecipitation (THOC5-FICD interaction), subcellular fractionation/localization, osteoclast differentiation assay\",\n      \"journal\": \"European journal of cell biology\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2-3 / Moderate — Co-IP, localization assay, functional KD with defined molecular and cellular phenotype, single lab\",\n      \"pmids\": [\"35688054\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2016,\n      \"finding\": \"MPL W515L mutant receptor induces phosphorylation of THOC5 on tyrosine 225, which mediates dysregulation of MYC mRNA expression (RNA transport) and increased chemokinesis. This was demonstrated by site-directed mutagenesis showing that THOC5 Y225 phosphorylation is required for MPL W515L-mediated effects on chemokinesis and MYC expression.\",\n      \"method\": \"Proteomics (relative quantification mass spectrometry), site-directed mutagenesis (Y225), chemokinesis assay, primary CD34+ patient cells\",\n      \"journal\": \"Oncotarget\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2-3 / Moderate — mutagenesis and functional assays with patient cell validation, single lab\",\n      \"pmids\": [\"26919114\"],\n      \"is_preprint\": false\n    }\n  ],\n  \"current_model\": \"THOC5 is a subunit of the mammalian THO/TREX mRNA export complex that functions as a selective mRNA export adaptor and 3'-processing co-factor: it binds directly to the Tap-p15 export receptor (at a site distinct from the Aly adaptor), interacts with CFIm68 and CPSF100 to regulate co-transcriptional polyadenylation site choice, recruits CDK12 to R-loops to regulate transcription elongation rate, and mediates nuclear export of a specific subset (~1% total, but >90% of inducible/immediate-early) mRNAs; its activity is regulated by phosphorylation—by c-Fms/PKC on S5/S6 (controlling nuclear-cytoplasmic localization), by Src/leukemogenic tyrosine kinases on Y225 (controlling mRNA-binding and chemokinesis), and by ATM kinase (suppressing mRNA-binding after DNA damage)—making it an essential factor for hematopoietic stem cell survival, cytokine-induced differentiation, and intestinal epithelial homeostasis.\"\n}\n```","stage2_raw":"{\n  \"mechanistic_narrative\": \"THOC5 is a subunit of the mammalian THO/TREX complex that acts as a selective mRNA export adaptor coupling co-transcriptional 3'-end processing to nuclear export of a defined subset of transcripts rather than bulk mRNA [#0, #6]. It binds directly to a distinct, non-overlapping surface on the Ntf2-like middle domain of the Tap export receptor—allowing simultaneous Tap engagement by THOC5 and the Aly adaptor—and exhibits intrinsic RNA-binding activity within stable THO mRNPs [#0]. Through direct interaction with the cleavage/polyadenylation machinery, THOC5 governs poly(A) site choice: it loads CFIm68 co-transcriptionally to favor distal polyadenylation sites and recruits CPSF100 to the 3'UTRs of target genes, so that loss of THOC5 yields chromatin-retained transcripts, shortened 3'UTRs, and failed export [#7, #10]. THOC5 is recruited to chromatin near sites of high RNA polymerase II density and, via interaction with CDK12 and THOC6, modulates polymerase II elongation rate and CDK12 recruitment to R-loops, mechanistically linking it to transcription as well as processing [#16]. The factor is selectively required for export of inducible and immediate-early transcripts—including heat-shock, M-CSF, Wnt, and serum-responsive genes (Hsp70, Ets1, Sox9, Ascl2, Myc, and immediate-early genes)—with over 90% of serum-induced immediate-early genes failing induction upon THOC5 loss [#6, #8, #9, #10]. THOC5 activity is gated by signaling-dependent phosphorylation: PKC phosphorylates serines 5/6 adjacent to its NLS to drive nuclear-to-cytoplasmic translocation [#2], Src-family and leukemogenic tyrosine kinases phosphorylate Y225 to control mRNA-binding and chemokinesis [#12, #19], and the ATM-p53 pathway suppresses its mRNA-binding after DNA damage [#11]. Consistent with its role in inducible gene expression, conditional deletion in mice causes rapid apoptosis of hematopoietic progenitors and disrupts intestinal epithelial homeostasis, and its activity is co-opted in leukemia and breast cancer stem-like states [#5, #9, #15].\",\n  \"teleology\": [\n    {\n      \"year\": 1999,\n      \"claim\": \"Established the first molecular handle on THOC5 as a signaling-responsive protein by showing it transiently associates with an activated receptor tyrosine kinase, raising the question of how a cytokine receptor connects to this factor.\",\n      \"evidence\": \"Co-IP and GST-Fms pulldown with deletion mutagenesis in cell systems\",\n      \"pmids\": [\"10597251\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Did not define THOC5's downstream nuclear function\", \"Functional consequence of the transient Fms binding for differentiation unresolved at this stage\"]\n    },\n    {\n      \"year\": 2004,\n      \"claim\": \"Answered how THOC5 subcellular distribution is controlled, showing PKC phosphorylation near the NLS shifts it from nucleus to cytoplasm and links this to differentiation signaling.\",\n      \"evidence\": \"Phosphomimetic/non-phosphorylatable S5/S6 mutants with localization and differentiation assays\",\n      \"pmids\": [\"15221008\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Did not connect localization control to a specific mRNA export function\", \"Endogenous PKC kinase identity in vivo not pinned down\"]\n    },\n    {\n      \"year\": 2006,\n      \"claim\": \"Provided the first link between THOC5 and RNA processing, showing it is needed for production of polyadenylated C/EBPalpha mRNA and is part of the THO complex during lineage decisions.\",\n      \"evidence\": \"Overexpression/knockdown with Northern blot, RT-PCR, and Co-IP in C2C12 cells\",\n      \"pmids\": [\"16909111\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Mechanism of processing/export selectivity undefined\", \"Direct vs indirect effect on C/EBPalpha not separated\"]\n    },\n    {\n      \"year\": 2008,\n      \"claim\": \"Defined THOC5 as a partner-import platform by showing it directly binds and chaperones THOC7 into the nucleus, clarifying THO complex assembly.\",\n      \"evidence\": \"Co-IP, domain-mapping deletion mutagenesis, and co-localization imaging\",\n      \"pmids\": [\"19059247\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Structural basis of the THOC5-THOC7 interface not resolved\", \"Whether nuclear import of THOC7 is required for export function untested\"]\n    },\n    {\n      \"year\": 2008,\n      \"claim\": \"Connected THOC5 to oncogenic signaling and survival, showing leukemogenic tyrosine kinases phosphorylate it to elevate PIP3 and suppress apoptosis, and that it associates with C/EBPbeta to drive myeloid maturation.\",\n      \"evidence\": \"Mass spectrometry phosphosite identification, PIP3/PtdInsP3 and apoptosis assays, Co-IP, ectopic expression\",\n      \"pmids\": [\"18373705\", \"19015024\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Mechanistic link between phosphorylation, PIP3 elevation, and mRNA function unclear\", \"Direct vs indirect C/EBPbeta interaction not fully validated\"]\n    },\n    {\n      \"year\": 2009,\n      \"claim\": \"Resolved how THOC5 interfaces with the export machinery, demonstrating direct binding to a Tap surface distinct from Aly and selective requirement for HSP70 mRNA export but not bulk export.\",\n      \"evidence\": \"Reciprocal in vitro binding (GST pulldown), Co-IP, RNA-binding assays, and knockdown export assays\",\n      \"pmids\": [\"19165146\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Did not define the full set of THOC5-dependent transcripts\", \"Determinants of transcript selectivity unknown\"]\n    },\n    {\n      \"year\": 2010,\n      \"claim\": \"Established the in vivo physiological essentiality of THOC5, showing its loss triggers rapid hematopoietic progenitor apoptosis and destabilizes THO complex partner THOC1.\",\n      \"evidence\": \"Interferon-inducible conditional knockout mouse with bone marrow transplant rescue and flow cytometry\",\n      \"pmids\": [\"20051105\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Which essential target mRNAs underlie progenitor survival not identified\", \"Cell-type specificity of dependence not mapped\"]\n    },\n    {\n      \"year\": 2011,\n      \"claim\": \"Defined THOC5 as a selective export factor for ~10 spliced transcripts and showed Hsp70 export is THOC5-dependent only under heat stress, framing it as a stress/inducible-mRNA export factor.\",\n      \"evidence\": \"Cre-lox conditional KO MEFs with cytoplasmic transcriptome analysis and RIP\",\n      \"pmids\": [\"21525145\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Sequence/structural features marking THOC5-dependent transcripts unknown\", \"Stage at which selectivity is imposed not defined\"]\n    },\n    {\n      \"year\": 2011,\n      \"claim\": \"Answered how DNA damage modulates THOC5, showing the ATM-p53 pathway suppresses its mRNA-binding via its C-terminal domain, linking export to the damage response.\",\n      \"evidence\": \"RIP, ATM inhibitor (KU55933), ATM/p53 siRNA epistasis, and C-terminal/PEST mutants\",\n      \"pmids\": [\"21937706\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Whether ATM directly phosphorylates THOC5 not established\", \"The C-terminal regulatory residues not pinpointed\"]\n    },\n    {\n      \"year\": 2012,\n      \"claim\": \"Identified Y225 as a tyrosine-kinase-controlled switch for THOC5 mRNA-binding and cell motility, dysregulated in CML and drug-targetable.\",\n      \"evidence\": \"MS phosphosite mapping, Y225 mutagenesis, in vitro kinase/phosphatase (Src/CD45) assays, chemokinesis assays, primary CML cells\",\n      \"pmids\": [\"23032722\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"How Y225 phosphorylation alters RNA contacts mechanistically unclear\", \"Full set of Y225-dependent transcripts not enumerated\"]\n    },\n    {\n      \"year\": 2013,\n      \"claim\": \"Mechanistically united THOC5 with co-transcriptional 3'-end processing and inducible gene programs, showing it loads CFIm68 to set poly(A) site choice and is needed for processing/export of M-CSF and Wnt target mRNAs.\",\n      \"evidence\": \"Co-IP, ChIP-seq, microarray, inducible conditional KO, RIP across multiple studies\",\n      \"pmids\": [\"23685434\", \"24157873\", \"24267292\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Direct vs bridged nature of THOC5-CFIm68 contact not crystallographically defined\", \"How processing defect is mechanistically coupled to export block not fully separated\"]\n    },\n    {\n      \"year\": 2014,\n      \"claim\": \"Extended the processing role to immediate-early gene induction, showing THOC5 recruits CPSF100 to target 3'UTRs and is required for serum induction of >90% of immediate-early genes.\",\n      \"evidence\": \"MS interactome with THOC5 bait, chromatin association assays, transcriptomics, serum stimulation with knockdown\",\n      \"pmids\": [\"25274738\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Order of CFIm68 vs CPSF100 recruitment not resolved\", \"Determinants targeting THOC5 to IEG loci unknown\"]\n    },\n    {\n      \"year\": 2016,\n      \"claim\": \"Generalized the Y225 switch to other leukemogenic receptors, showing MPL W515L drives Y225 phosphorylation to dysregulate MYC transport and chemokinesis.\",\n      \"evidence\": \"Quantitative proteomics, Y225 mutagenesis, chemokinesis assays, primary CD34+ patient cells\",\n      \"pmids\": [\"26919114\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Direct kinase responsible for Y225 in this context not confirmed\", \"Mechanism linking Y225 to MYC mRNA selectivity unclear\"]\n    },\n    {\n      \"year\": 2021,\n      \"claim\": \"Implicated THOC5 in cancer stemness, showing it is required for THOC2-dependent export of SOX2/NANOG mRNAs and radioresistance in triple-negative breast cancer.\",\n      \"evidence\": \"siRNA knockdown, xenograft assays, protein expression analysis\",\n      \"pmids\": [\"34708581\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Direct THOC5 binding to SOX2/NANOG transcripts not shown here\", \"Whether processing or export step is rate-limiting undefined\"]\n    },\n    {\n      \"year\": 2022,\n      \"claim\": \"Revealed a transcription-elongation arm of THOC5 function, showing chromatin-associated THOC5 interacts with CDK12, DDX5/17, and THOC6 to set polymerase II elongation rate and recruit CDK12 to R-loops.\",\n      \"evidence\": \"Depletion plus in vivo elongation rate measurement, ChIP-seq, chromatin Co-IP, R-loop analysis; plus M-CSF-dependent shuttling and FICD binding in osteoclast precursors\",\n      \"pmids\": [\"36590164\", \"35688054\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Causal hierarchy between elongation control, R-loop resolution, and processing not resolved\", \"Structural basis of CDK12-THOC5-THOC6 assembly unknown\"]\n    },\n    {\n      \"year\": 2024,\n      \"claim\": \"Linked THOC5 to oncogenic splicing-factor mutation, showing SF3B1 K700E weakens SF3B1-THOC5 interaction and impairs export of THOC5-bound mRNAs, rescuable by THOC5 overexpression.\",\n      \"evidence\": \"Co-IP (mutant vs WT SF3B1), RIP, nuclear export assays, THOC5 overexpression rescue\",\n      \"pmids\": [\"39259498\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Whether SF3B1-THOC5 contact is direct not established\", \"Identity of the affected transcript set incompletely defined\"]\n    },\n    {\n      \"year\": null,\n      \"claim\": \"What molecular features mark a transcript as THOC5-dependent, and how phosphorylation, processing, elongation, and export selectivity are mechanistically integrated, remains unresolved.\",\n      \"evidence\": \"\",\n      \"pmids\": [],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"No structural model of THOC5 in the THO/TREX complex with its processing/export partners\", \"Cis-determinants of THOC5 target selectivity unknown\", \"Causal ordering of elongation control vs 3'-processing vs export not established\"]\n    }\n  ],\n  \"mechanism_profile\": {\n    \"molecular_activity\": [\n      {\"term_id\": \"GO:0003723\", \"supporting_discovery_ids\": [0, 6, 8, 11, 12]},\n      {\"term_id\": \"GO:0060090\", \"supporting_discovery_ids\": [0, 7, 10]},\n      {\"term_id\": \"GO:0140098\", \"supporting_discovery_ids\": [7, 10, 16]}\n    ],\n    \"localization\": [\n      {\"term_id\": \"GO:0005654\", \"supporting_discovery_ids\": [2, 8]},\n      {\"term_id\": \"GO:0005634\", \"supporting_discovery_ids\": [0, 2, 3, 8]},\n      {\"term_id\": \"GO:0005829\", \"supporting_discovery_ids\": [2, 8, 18]},\n      {\"term_id\": \"GO:0000228\", \"supporting_discovery_ids\": [8, 10, 16]}\n    ],\n    \"pathway\": [\n      {\"term_id\": \"R-HSA-8953854\", \"supporting_discovery_ids\": [0, 6, 7, 10]},\n      {\"term_id\": \"R-HSA-74160\", \"supporting_discovery_ids\": [7, 10, 16]},\n      {\"term_id\": \"R-HSA-9609507\", \"supporting_discovery_ids\": [0, 6, 17]},\n      {\"term_id\": \"R-HSA-8953897\", \"supporting_discovery_ids\": [6, 11]}\n    ],\n    \"complexes\": [\"THO/TREX complex\"],\n    \"partners\": [\"TAP/NXF1\", \"ALYREF\", \"THOC1\", \"THOC7\", \"CPSF6/CFIm68\", \"CPSF2/CPSF100\", \"CDK12\", \"SF3B1\"],\n    \"other_free_text\": []\n  }\n}","audit_flag":null,"evaluation":{"pairwise":"win","faith_supported":7,"faith_total":7,"faith_pct":100.0}}