{"gene":"TAF1B","run_date":"2026-06-10T10:51:54","timeline":{"discoveries":[{"year":1995,"finding":"TAF1B (TAFI63) is a subunit of the RNA Pol I promoter selectivity factor SL1 (composed of TBP, TAFI110, TAFI63/TAF1B, and TAFI48). Both TAFI110 and TAFI63 contact the rRNA gene promoter DNA directly, while TAFI48 (not TAF1B) serves as the target for UBF interaction and class-specific promoter selectivity.","method":"In vitro transcription assay, protein-DNA contact analysis, reconstitution of SL1 complex","journal":"Science","confidence":"High","confidence_rationale":"Tier 1 / Strong — in vitro reconstitution with functional transcription assays and direct contact mapping; foundational study replicated across labs","pmids":["7491500"],"is_preprint":false},{"year":1996,"finding":"TBP colocalizes with TAF(I)s (including TAF(I)63/TAF1B), UBF, and RNA Pol I at rRNA gene sites in both actively transcribing and mitotically silenced nucleoli; anti-TBP antibodies co-immunoprecipitate TAF(I)63 from both untreated and actinomycin D-treated cell extracts, demonstrating stable SL1 complex association with rRNA genes regardless of transcriptional activity.","method":"Immunofluorescence colocalization, co-immunoprecipitation from mammalian cell extracts","journal":"The Journal of cell biology","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — reciprocal colocalization and Co-IP with two conditions (active/inactive transcription), single lab","pmids":["8609157"],"is_preprint":false},{"year":2001,"finding":"hRRN3 (the initiation-competent Pol I co-factor) interacts directly with TAF(I)110 and TAF(I)63/TAF1B within SL1; blocking this RRN3–TAF1B/TAF(I)63 interaction prevents recruitment of the transcriptionally active Pol I (Pol I-beta) to the rDNA promoter.","method":"Co-immunoprecipitation, direct protein interaction assay, in vitro transcription with blocking experiments","journal":"The EMBO journal","confidence":"High","confidence_rationale":"Tier 1 / Strong — direct binding assay combined with functional block of Pol I recruitment to promoter, multiple orthogonal methods","pmids":["11250903"],"is_preprint":false},{"year":2004,"finding":"The carboxyl-terminal 51 residues of TAF(I)48 (a binding partner of TAF1B within SL1) are necessary and sufficient for nucleolar/nuclear localization and associate with multiple beta-karyopherin import receptors (importin beta, transportin, RanBP5) in a Ran-dependent manner, identifying the first nuclear import sequence within SL1 TAF subunits.","method":"Domain deletion analysis, GFP localization assay, GST pull-down with karyopherins, Ran-dependent binding assay","journal":"Journal of biochemistry","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — direct localization domain mapping plus binding assays; single lab, multiple orthogonal methods; note this is for the SL1 partner TAF(I)48, not TAF1B itself","pmids":["15113842"],"is_preprint":false},{"year":2004,"finding":"TAF1B (TAF(I)63) directly binds TBP within SL1; a TBP-binding domain was identified in the carboxyl-terminus of the SL1 partner TAF(I)48, and residues within helix 2 of TBP (shared with TFIID and TFIIIB interactions) are required for this interaction, indicating conserved TBP-contact surfaces across Pol I, II, and III complexes.","method":"Yeast two-hybrid, GST pull-down, site-directed mutagenesis of TBP and TAF(I)48","journal":"Gene","confidence":"Medium","confidence_rationale":"Tier 1 / Moderate — mutagenesis plus direct binding assays in vitro; single lab, multiple methods but for TBP-TAF(I)48 interaction within the SL1 complex that contains TAF1B","pmids":["15315821"],"is_preprint":false},{"year":2007,"finding":"Toxoplasma gondii GRA10 protein interacts with human TAF1B in the nucleolus; the interaction was confirmed by GST pull-down and co-immunoprecipitation, and both proteins co-localize in the nucleolus after co-transfection, with GRA10's nucleolar localization being actinomycin D-sensitive (consistent with dependence on active rRNA transcription).","method":"Yeast two-hybrid, GST pull-down, co-immunoprecipitation, immunofluorescence colocalization","journal":"The Korean journal of parasitology","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — reciprocal binding confirmed by pull-down and Co-IP plus colocalization; single lab, multiple orthogonal methods","pmids":["17876161"],"is_preprint":false},{"year":2011,"finding":"TAF1B, a subunit of human SL1, is structurally related to TFIIB/TFIIB-like proteins through predicted N-terminal zinc ribbon and cyclin-like fold domains. TAF1B has an essential post-Pol I recruitment role in preinitiation complex assembly at the rRNA gene promoter, in addition to SL1's established role in Pol I recruitment.","method":"Structural homology prediction, domain swap experiments, functional rescue assays for Pol I transcription","journal":"Science","confidence":"High","confidence_rationale":"Tier 1 / Strong — structural analysis combined with functional domain swap and complementation assays; simultaneously replicated by independent lab (PMID 21921198)","pmids":["21921199"],"is_preprint":false},{"year":2011,"finding":"Yeast Rrn7 (ortholog of human TAF1B) is a TFIIB-like factor and a subunit of the yeast Pol I core factor; domain swaps between TFIIB-related factors show Rrn7 is most closely related to the Pol III factor Brf1, establishing evolutionary conservation of TFIIB-like initiation factors across all three eukaryotic RNA polymerase systems.","method":"Sequence analysis, structural domain comparison, TFIIB-related domain swapping functional assays","journal":"Science","confidence":"High","confidence_rationale":"Tier 1 / Strong — functional domain swaps and ortholog complementation; simultaneously replicated by independent lab (PMID 21921199)","pmids":["21921198"],"is_preprint":false},{"year":2014,"finding":"In Drosophila, TAF1B is part of an RNA Pol I regulatory complex with Udd (Under-developed) and a TAF1C-like factor. Disruption of TAF1B reduces rRNA transcription and causes reduced ovarian germline stem cell (GSC) proliferation, demonstrating TAF1B is required for rRNA synthesis and GSC maintenance.","method":"Genetic disruption (Drosophila loss-of-function), rRNA transcription measurement, GSC proliferation assay","journal":"Science","confidence":"High","confidence_rationale":"Tier 2 / Strong — genetic loss-of-function with defined cellular phenotype (GSC proliferation) plus biochemical complex identification; replicated across multiple experiments","pmids":["24436420"],"is_preprint":false},{"year":2017,"finding":"In Drosophila germline cells, TAF1B (component of the SL1-like complex) is required for nucleolar localization of Udd (another SL1-like complex subunit); knockdown of TAF1B in germline cells leads to accumulation of late-stage egg chambers due to reduced rRNA transcription. Knockdown of TAF1B does not disrupt Piwi nucleolar localization, placing TAF1B downstream of Piwi in the nucleolar recruitment pathway.","method":"RNAi knockdown in Drosophila, immunofluorescence localization, genetic epistasis","journal":"Molekuliarnaia biologiia","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — epistasis by knockdown plus direct localization imaging; single lab","pmids":["29116069"],"is_preprint":false},{"year":2019,"finding":"KDM4 histone demethylases (KDM4A/B/C) are required for expression of Taf1b in hematopoietic stem cells; conditional triple knockout of KDM4 demethylases leads to H3K9me3 accumulation at the Taf1b transcription start site and downregulation of Taf1b expression, and Taf1b is shown to be essential for maintenance of hematopoietic cells.","method":"Conditional triple-knockout mice, ChIP for H3K9me3, gene expression analysis, functional rescue","journal":"Blood","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — genetic KO with ChIP validation of H3K9me3 at TAF1B locus; single lab with multiple methods","pmids":["31434704"],"is_preprint":false},{"year":2022,"finding":"Conditional deletion of the TAF1B subunit of SL1 causes striking depletion of UBTF specifically at both rRNA gene promoters (but not elsewhere across the rDNA), demonstrating that TAF1B/SL1 is required for stable UBTF1 engagement at rDNA promoters and that UBTF1–SL1 cooperation generates rDNA promoter specificity in an induced-fit mechanism.","method":"Conditional TAF1B deletion, ChIP-seq for UBTF at rDNA promoters, quantitative genomic analysis","journal":"PLoS genetics","confidence":"High","confidence_rationale":"Tier 2 / Strong — conditional gene deletion combined with ChIP-seq showing specific loss of UBTF at promoters; multiple orthogonal methods and strong genetic evidence","pmids":["35139074"],"is_preprint":false},{"year":2022,"finding":"In Drosophila, impaired function of TAF1B (a subunit of the SL1-like complex) leads to derepression of R2-retrotransposon-containing rDNA units, accompanied by reduction of H3K9me3 and HP1a marks at those loci, suggesting the SL1-like complex participates in selective activation of intact rDNA units in competition with heterochromatin formation.","method":"RNAi knockdown of TAF1B in Drosophila ovaries, ChIP for H3K9me3/HP1a, quantitative RT-PCR of R2 elements","journal":"Nucleic acids research","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — genetic knockdown with ChIP validation; single lab, two orthogonal methods","pmids":["35037046"],"is_preprint":false},{"year":2023,"finding":"TAF1B depletion in hepatocellular carcinoma cells disrupts the pre-initiation complex (PIC) at rDNA, reduces Pol I binding to rDNA (validated by ChIP), decreases pre-rRNA levels, induces nucleolar stress, and triggers apoptosis via a p53–miR-101 feedback circuit in which Pol I transcription repression activates p53, which induces miR-101, and miR-101 negatively feeds back by inhibiting the p53-mediated PARP pathway.","method":"Lentiviral knockdown, Co-IP, ChIP, FISH for rDNA activity, immunofluorescence, xenograft tumor model, Western blot for apoptosis markers","journal":"Frontiers in oncology","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — multiple orthogonal methods (ChIP, Co-IP, FISH, xenograft) in single lab; mechanistic pathway defined but some steps inferred","pmids":["37645431"],"is_preprint":false},{"year":2023,"finding":"TAF1B knockdown in stomach adenocarcinoma cells disrupts the Pol I pre-initiation complex, impairs rRNA gene transcription and ribosome biogenesis, induces nucleolar stress, and promotes c-MYC mRNA degradation, resulting in inhibition of cell proliferation and survival in vitro and in vivo.","method":"RNAi knockdown, in vitro proliferation assay, xenograft model, qRT-PCR for pre-rRNA, Western blot for c-MYC","journal":"Heliyon","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — KD with defined cellular and molecular phenotype in vitro and in vivo; single lab, multiple readouts","pmids":["38169774"],"is_preprint":false}],"current_model":"TAF1B is a subunit of the human RNA Polymerase I basal transcription factor SL1 (Selectivity Factor 1) and is structurally related to TFIIB/TFIIB-like proteins through N-terminal zinc ribbon and cyclin-like fold domains; within SL1 it directly contacts the rDNA promoter, is required for stable UBTF1 engagement at promoters (induced-fit recognition), mediates RRN3-dependent recruitment of transcriptionally active Pol I to the preinitiation complex, and has an essential post-Pol I recruitment role in PIC assembly, such that its depletion reduces rRNA synthesis, triggers nucleolar stress, and—through p53 and c-MYC pathways—induces apoptosis and blocks cell proliferation."},"narrative":{"mechanistic_narrative":"TAF1B is a subunit of the human RNA Polymerase I promoter selectivity factor SL1, where it functions as a core component of the basal machinery that drives transcription of ribosomal RNA genes [PMID:7491500]. Within SL1 it directly contacts rDNA promoter DNA, and the complex stably associates with rRNA gene sites independent of transcriptional state [PMID:7491500, PMID:8609157]. TAF1B is structurally related to TFIIB/TFIIB-like initiation factors through predicted N-terminal zinc ribbon and cyclin-like fold domains, an architecture conserved through its yeast ortholog Rrn7, establishing TFIIB-like factors as common initiation components across all three eukaryotic RNA polymerase systems [PMID:21921199, PMID:21921198]. Mechanistically, TAF1B interacts directly with the initiation-competent cofactor RRN3 to recruit transcriptionally active Pol I to the rDNA promoter, and it carries an additional essential role in preinitiation complex assembly that follows Pol I recruitment [PMID:11250903, PMID:21921199]. SL1 function through TAF1B is also required for stable engagement of UBTF at rRNA gene promoters, generating promoter specificity through an induced-fit mechanism [PMID:35139074]. Loss of TAF1B collapses the Pol I preinitiation complex, reduces pre-rRNA synthesis, and triggers nucleolar stress that activates p53- and c-MYC-dependent programs to induce apoptosis and block proliferation in cancer cells [PMID:37645431, PMID:38169774]. Across model organisms, TAF1B is required for rRNA synthesis supporting germline stem cell proliferation and hematopoietic cell maintenance [PMID:24436420, PMID:31434704].","teleology":[{"year":1995,"claim":"Established TAF1B as a defined subunit of the Pol I selectivity factor SL1 that directly contacts rDNA promoter DNA, identifying its place in the basal rRNA transcription machinery.","evidence":"In vitro reconstitution of SL1 with transcription assays and protein-DNA contact mapping","pmids":["7491500"],"confidence":"High","gaps":["Atomic structure of TAF1B within SL1 not resolved","Specific promoter DNA bases contacted by TAF1B versus TAFI110 not delineated"]},{"year":1996,"claim":"Showed SL1 (including TAF1B) remains stably bound to rRNA genes regardless of transcriptional activity, indicating constitutive promoter occupancy rather than activity-dependent recruitment.","evidence":"Immunofluorescence colocalization and anti-TBP Co-IP from active and actinomycin D-treated cell extracts","pmids":["8609157"],"confidence":"Medium","gaps":["Single-lab observation","Does not address dynamics of complex turnover"]},{"year":2001,"claim":"Identified TAF1B as a direct binding partner of the initiation factor RRN3, linking SL1 to recruitment of the transcriptionally active form of Pol I.","evidence":"Co-IP, direct interaction assay, and in vitro transcription with interaction-blocking experiments","pmids":["11250903"],"confidence":"High","gaps":["Interaction interface on TAF1B not mapped at residue level","How RRN3 binding is regulated remains unaddressed"]},{"year":2004,"claim":"Characterized TBP-contact and nuclear import surfaces within SL1 TAF subunits, defining how the complex containing TAF1B assembles and localizes, though the mapped determinants reside on the partner TAFI48.","evidence":"Yeast two-hybrid, GST pull-down, GFP localization, and site-directed mutagenesis of TBP and TAFI48","pmids":["15113842","15315821"],"confidence":"Medium","gaps":["Determinants mapped on TAFI48, not TAF1B itself","TAF1B's own import and TBP-contact contributions not isolated"]},{"year":2007,"claim":"Reported a pathogen (Toxoplasma GRA10) interaction with nucleolar TAF1B, indicating TAF1B can be targeted at the nucleolus by exogenous factors.","evidence":"Yeast two-hybrid, GST pull-down, Co-IP, and immunofluorescence colocalization","pmids":["17876161"],"confidence":"Medium","gaps":["Functional consequence for host rRNA transcription unknown","Single-lab, non-physiological co-transfection context"]},{"year":2011,"claim":"Resolved TAF1B as a TFIIB-like factor with zinc ribbon and cyclin-fold domains and an essential post-recruitment role in PIC assembly, unifying initiation mechanisms across the three RNA polymerase systems.","evidence":"Structural homology prediction, domain swaps, and functional complementation; corroborated by yeast Rrn7 ortholog analysis","pmids":["21921199","21921198"],"confidence":"High","gaps":["Precise step in PIC assembly executed by TAF1B not defined","No experimental high-resolution structure of human TAF1B"]},{"year":2014,"claim":"Demonstrated through genetic loss-of-function that TAF1B is required for rRNA synthesis supporting germline stem cell proliferation, linking the molecular function to a developmental cellular output.","evidence":"Drosophila loss-of-function genetics, rRNA transcription measurement, GSC proliferation assay","pmids":["24436420"],"confidence":"High","gaps":["Drosophila complex composition may differ from human SL1","Tissue-specific requirements in mammals not addressed here"]},{"year":2017,"claim":"Placed TAF1B downstream of Piwi and upstream of Udd in nucleolar recruitment, ordering the SL1-like complex assembly pathway in germline cells.","evidence":"RNAi knockdown, immunofluorescence localization, and genetic epistasis in Drosophila","pmids":["29116069"],"confidence":"Medium","gaps":["Molecular basis of TAF1B-dependent Udd recruitment unknown","Conservation of this hierarchy in mammals untested"]},{"year":2019,"claim":"Showed Taf1b expression is epigenetically controlled by KDM4 demethylases and is essential for hematopoietic cell maintenance, connecting TAF1B regulation to stem cell homeostasis.","evidence":"Conditional triple-knockout mice, H3K9me3 ChIP at the Taf1b TSS, expression and rescue analysis","pmids":["31434704"],"confidence":"Medium","gaps":["Direct demonstration that rRNA loss mediates the hematopoietic phenotype not provided","Single-lab finding"]},{"year":2022,"claim":"Established that TAF1B/SL1 is required for stable UBTF engagement specifically at rRNA gene promoters, defining an induced-fit mechanism generating rDNA promoter specificity.","evidence":"Conditional TAF1B deletion with ChIP-seq for UBTF across rDNA","pmids":["35139074"],"confidence":"High","gaps":["Structural basis of induced-fit cooperation not resolved","Order of UBTF versus SL1 binding events not fully established"]},{"year":2022,"claim":"Implicated the TAF1B-containing complex in selective activation of intact rDNA units in competition with heterochromatin, linking SL1 to rDNA copy-number/chromatin regulation.","evidence":"Drosophila RNAi knockdown, ChIP for H3K9me3/HP1a, qRT-PCR of R2 retrotransposon elements","pmids":["35037046"],"confidence":"Medium","gaps":["Direct role of TAF1B in chromatin mark deposition versus indirect effect unclear","Mammalian relevance untested"]},{"year":2023,"claim":"Connected TAF1B-dependent PIC integrity to tumor cell viability, showing depletion collapses Pol I transcription and triggers nucleolar-stress apoptosis via p53/c-MYC pathways.","evidence":"Lentiviral/RNAi knockdown, ChIP, Co-IP, FISH, xenograft models, and apoptosis/proliferation readouts in hepatocellular and stomach carcinoma cells","pmids":["37645431","38169774"],"confidence":"Medium","gaps":["Some pathway steps (p53-miR-101 feedback) are inferred rather than directly demonstrated","Single-lab studies per tumor type"]},{"year":null,"claim":"How TAF1B coordinates its sequential RRN3-mediated Pol I recruitment and post-recruitment PIC assembly roles at atomic resolution, and how these are regulated to control rRNA output, remains unresolved.","evidence":"","pmids":[],"confidence":"High","gaps":["No experimental high-resolution structure of human SL1 with TAF1B","Regulatory inputs governing TAF1B activity in human cells undefined"]}],"mechanism_profile":{"molecular_activity":[{"term_id":"GO:0003677","term_label":"DNA binding","supporting_discovery_ids":[0]},{"term_id":"GO:0140110","term_label":"transcription regulator activity","supporting_discovery_ids":[0,2,6]},{"term_id":"GO:0140223","term_label":"general transcription initiation factor activity","supporting_discovery_ids":[0,6]}],"localization":[{"term_id":"GO:0005730","term_label":"nucleolus","supporting_discovery_ids":[1,5,9]},{"term_id":"GO:0005634","term_label":"nucleus","supporting_discovery_ids":[1]}],"pathway":[{"term_id":"R-HSA-74160","term_label":"Gene expression (Transcription)","supporting_discovery_ids":[0,2,6,11]},{"term_id":"R-HSA-8953854","term_label":"Metabolism of RNA","supporting_discovery_ids":[8,14]},{"term_id":"R-HSA-5357801","term_label":"Programmed Cell Death","supporting_discovery_ids":[13]}],"complexes":["SL1 (Selectivity Factor 1)","RNA Pol I core factor (yeast Rrn7)"],"partners":["TBP","RRN3","TAF1A","TAF1C","UBTF"],"other_free_text":[]}},"prefetch_data":{"uniprot":{"accession":"Q53T94","full_name":"TATA box-binding protein-associated factor RNA polymerase I subunit B","aliases":["RNA polymerase I-specific TBP-associated factor 63 kDa","TAFI63","TATA box-binding protein-associated factor 1B","TBP-associated factor 1B","Transcription initiation factor SL1/TIF-IB subunit B"],"length_aa":588,"mass_kda":68.8,"function":"Component of RNA polymerase I core factor complex that acts as a GTF2B/TFIIB-like factor and plays a key role in multiple steps during transcription initiation such as pre-initiation complex (PIC) assembly and postpolymerase recruitment events in polymerase I (Pol I) transcription. Binds rDNA promoters and plays a role in Pol I recruitment as a component of the SL1/TIF-IB complex and, possibly, directly through its interaction with RRN3","subcellular_location":"Nucleus, nucleolus","url":"https://www.uniprot.org/uniprotkb/Q53T94/entry"},"depmap":{"release":"DepMap","has_data":true,"is_common_essential":true,"resolved_as":"","url":"https://depmap.org/portal/gene/TAF1B","classification":"Common Essential","n_dependent_lines":1046,"n_total_lines":1208,"dependency_fraction":0.8658940397350994},"opencell":{"profiled":false,"resolved_as":"","ensg_id":"","cell_line_id":"","localizations":[],"interactors":[{"gene":"PSMG1","stoichiometry":0.2},{"gene":"TBP","stoichiometry":0.2}],"url":"https://opencell.sf.czbiohub.org/search/TAF1B","total_profiled":1310},"omim":[{"mim_id":"612823","title":"TATA BOX-BINDING PROTEIN-ASSOCIATED FACTOR 1D; TAF1D","url":"https://www.omim.org/entry/612823"},{"mim_id":"610770","title":"NOC2-LIKE NUCLEOLAR-ASSOCIATED TRANSCRIPTIONAL REPRESSOR; NOC2L","url":"https://www.omim.org/entry/610770"},{"mim_id":"609518","title":"THAP DOMAIN-CONTAINING PROTEIN 7; THAP7","url":"https://www.omim.org/entry/609518"},{"mim_id":"604905","title":"TATA BOX-BINDING PROTEIN-ASSOCIATED FACTOR 1C; TAF1C","url":"https://www.omim.org/entry/604905"},{"mim_id":"604904","title":"TATA BOX-BINDING PROTEIN-ASSOCIATED FACTOR 1B; TAF1B","url":"https://www.omim.org/entry/604904"}],"hpa":{"profiled":true,"resolved_as":"","reliability":"Supported","locations":[{"location":"Nucleoli","reliability":"Supported"},{"location":"Nucleoplasm","reliability":"Additional"}],"tissue_specificity":"Low tissue specificity","tissue_distribution":"Detected in all","driving_tissues":[],"url":"https://www.proteinatlas.org/search/TAF1B"},"hgnc":{"alias_symbol":["TAFI63","SL1","RAF1B","RAFI63"],"prev_symbol":[]},"alphafold":{"accession":"Q53T94","domains":[{"cath_id":"2.20.25","chopping":"2-42","consensus_level":"medium","plddt":77.592,"start":2,"end":42},{"cath_id":"-","chopping":"73-122_191-291","consensus_level":"medium","plddt":92.4129,"start":73,"end":291},{"cath_id":"-","chopping":"299-415_493-576","consensus_level":"medium","plddt":87.702,"start":299,"end":576}],"viewer_url":"https://alphafold.ebi.ac.uk/entry/Q53T94","model_url":"https://alphafold.ebi.ac.uk/files/AF-Q53T94-F1-model_v6.cif","pae_url":"https://alphafold.ebi.ac.uk/files/AF-Q53T94-F1-predicted_aligned_error_v6.png","plddt_mean":78.69},"mouse_models":{"mgi_url":"https://www.informatics.jax.org/marker/summary?nomen=TAF1B","jax_strain_url":"https://www.jax.org/strain/search?query=TAF1B"},"sequence":{"accession":"Q53T94","fasta_url":"https://rest.uniprot.org/uniprotkb/Q53T94.fasta","uniprot_url":"https://www.uniprot.org/uniprotkb/Q53T94/entry","alphafold_viewer_url":"https://alphafold.ebi.ac.uk/entry/Q53T94"}},"corpus_meta":[{"pmid":"29198723","id":"PMC_29198723","title":"DNA 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international","url":"https://pubmed.ncbi.nlm.nih.gov/39557707","citation_count":0,"is_preprint":false}],"cost":{"stage1":{"model":"claude-sonnet-4-6","input_tokens":21892,"output_tokens":3849,"usd":0.061706,"stage1_stop_reason":"end_turn"},"stage2":{"model":"claude-opus-4-8","input_tokens":11533,"output_tokens":3842,"usd":0.076857,"stage2_stop_reason":"end_turn"},"total_usd":0.138563,"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\": 1995,\n      \"finding\": \"TAF1B (TAFI63) is a subunit of the RNA Pol I promoter selectivity factor SL1 (composed of TBP, TAFI110, TAFI63/TAF1B, and TAFI48). Both TAFI110 and TAFI63 contact the rRNA gene promoter DNA directly, while TAFI48 (not TAF1B) serves as the target for UBF interaction and class-specific promoter selectivity.\",\n      \"method\": \"In vitro transcription assay, protein-DNA contact analysis, reconstitution of SL1 complex\",\n      \"journal\": \"Science\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1 / Strong — in vitro reconstitution with functional transcription assays and direct contact mapping; foundational study replicated across labs\",\n      \"pmids\": [\"7491500\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 1996,\n      \"finding\": \"TBP colocalizes with TAF(I)s (including TAF(I)63/TAF1B), UBF, and RNA Pol I at rRNA gene sites in both actively transcribing and mitotically silenced nucleoli; anti-TBP antibodies co-immunoprecipitate TAF(I)63 from both untreated and actinomycin D-treated cell extracts, demonstrating stable SL1 complex association with rRNA genes regardless of transcriptional activity.\",\n      \"method\": \"Immunofluorescence colocalization, co-immunoprecipitation from mammalian cell extracts\",\n      \"journal\": \"The Journal of cell biology\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — reciprocal colocalization and Co-IP with two conditions (active/inactive transcription), single lab\",\n      \"pmids\": [\"8609157\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2001,\n      \"finding\": \"hRRN3 (the initiation-competent Pol I co-factor) interacts directly with TAF(I)110 and TAF(I)63/TAF1B within SL1; blocking this RRN3–TAF1B/TAF(I)63 interaction prevents recruitment of the transcriptionally active Pol I (Pol I-beta) to the rDNA promoter.\",\n      \"method\": \"Co-immunoprecipitation, direct protein interaction assay, in vitro transcription with blocking experiments\",\n      \"journal\": \"The EMBO journal\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1 / Strong — direct binding assay combined with functional block of Pol I recruitment to promoter, multiple orthogonal methods\",\n      \"pmids\": [\"11250903\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2004,\n      \"finding\": \"The carboxyl-terminal 51 residues of TAF(I)48 (a binding partner of TAF1B within SL1) are necessary and sufficient for nucleolar/nuclear localization and associate with multiple beta-karyopherin import receptors (importin beta, transportin, RanBP5) in a Ran-dependent manner, identifying the first nuclear import sequence within SL1 TAF subunits.\",\n      \"method\": \"Domain deletion analysis, GFP localization assay, GST pull-down with karyopherins, Ran-dependent binding assay\",\n      \"journal\": \"Journal of biochemistry\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — direct localization domain mapping plus binding assays; single lab, multiple orthogonal methods; note this is for the SL1 partner TAF(I)48, not TAF1B itself\",\n      \"pmids\": [\"15113842\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2004,\n      \"finding\": \"TAF1B (TAF(I)63) directly binds TBP within SL1; a TBP-binding domain was identified in the carboxyl-terminus of the SL1 partner TAF(I)48, and residues within helix 2 of TBP (shared with TFIID and TFIIIB interactions) are required for this interaction, indicating conserved TBP-contact surfaces across Pol I, II, and III complexes.\",\n      \"method\": \"Yeast two-hybrid, GST pull-down, site-directed mutagenesis of TBP and TAF(I)48\",\n      \"journal\": \"Gene\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 1 / Moderate — mutagenesis plus direct binding assays in vitro; single lab, multiple methods but for TBP-TAF(I)48 interaction within the SL1 complex that contains TAF1B\",\n      \"pmids\": [\"15315821\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2007,\n      \"finding\": \"Toxoplasma gondii GRA10 protein interacts with human TAF1B in the nucleolus; the interaction was confirmed by GST pull-down and co-immunoprecipitation, and both proteins co-localize in the nucleolus after co-transfection, with GRA10's nucleolar localization being actinomycin D-sensitive (consistent with dependence on active rRNA transcription).\",\n      \"method\": \"Yeast two-hybrid, GST pull-down, co-immunoprecipitation, immunofluorescence colocalization\",\n      \"journal\": \"The Korean journal of parasitology\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — reciprocal binding confirmed by pull-down and Co-IP plus colocalization; single lab, multiple orthogonal methods\",\n      \"pmids\": [\"17876161\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2011,\n      \"finding\": \"TAF1B, a subunit of human SL1, is structurally related to TFIIB/TFIIB-like proteins through predicted N-terminal zinc ribbon and cyclin-like fold domains. TAF1B has an essential post-Pol I recruitment role in preinitiation complex assembly at the rRNA gene promoter, in addition to SL1's established role in Pol I recruitment.\",\n      \"method\": \"Structural homology prediction, domain swap experiments, functional rescue assays for Pol I transcription\",\n      \"journal\": \"Science\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1 / Strong — structural analysis combined with functional domain swap and complementation assays; simultaneously replicated by independent lab (PMID 21921198)\",\n      \"pmids\": [\"21921199\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2011,\n      \"finding\": \"Yeast Rrn7 (ortholog of human TAF1B) is a TFIIB-like factor and a subunit of the yeast Pol I core factor; domain swaps between TFIIB-related factors show Rrn7 is most closely related to the Pol III factor Brf1, establishing evolutionary conservation of TFIIB-like initiation factors across all three eukaryotic RNA polymerase systems.\",\n      \"method\": \"Sequence analysis, structural domain comparison, TFIIB-related domain swapping functional assays\",\n      \"journal\": \"Science\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1 / Strong — functional domain swaps and ortholog complementation; simultaneously replicated by independent lab (PMID 21921199)\",\n      \"pmids\": [\"21921198\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2014,\n      \"finding\": \"In Drosophila, TAF1B is part of an RNA Pol I regulatory complex with Udd (Under-developed) and a TAF1C-like factor. Disruption of TAF1B reduces rRNA transcription and causes reduced ovarian germline stem cell (GSC) proliferation, demonstrating TAF1B is required for rRNA synthesis and GSC maintenance.\",\n      \"method\": \"Genetic disruption (Drosophila loss-of-function), rRNA transcription measurement, GSC proliferation assay\",\n      \"journal\": \"Science\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — genetic loss-of-function with defined cellular phenotype (GSC proliferation) plus biochemical complex identification; replicated across multiple experiments\",\n      \"pmids\": [\"24436420\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2017,\n      \"finding\": \"In Drosophila germline cells, TAF1B (component of the SL1-like complex) is required for nucleolar localization of Udd (another SL1-like complex subunit); knockdown of TAF1B in germline cells leads to accumulation of late-stage egg chambers due to reduced rRNA transcription. Knockdown of TAF1B does not disrupt Piwi nucleolar localization, placing TAF1B downstream of Piwi in the nucleolar recruitment pathway.\",\n      \"method\": \"RNAi knockdown in Drosophila, immunofluorescence localization, genetic epistasis\",\n      \"journal\": \"Molekuliarnaia biologiia\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — epistasis by knockdown plus direct localization imaging; single lab\",\n      \"pmids\": [\"29116069\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2019,\n      \"finding\": \"KDM4 histone demethylases (KDM4A/B/C) are required for expression of Taf1b in hematopoietic stem cells; conditional triple knockout of KDM4 demethylases leads to H3K9me3 accumulation at the Taf1b transcription start site and downregulation of Taf1b expression, and Taf1b is shown to be essential for maintenance of hematopoietic cells.\",\n      \"method\": \"Conditional triple-knockout mice, ChIP for H3K9me3, gene expression analysis, functional rescue\",\n      \"journal\": \"Blood\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — genetic KO with ChIP validation of H3K9me3 at TAF1B locus; single lab with multiple methods\",\n      \"pmids\": [\"31434704\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2022,\n      \"finding\": \"Conditional deletion of the TAF1B subunit of SL1 causes striking depletion of UBTF specifically at both rRNA gene promoters (but not elsewhere across the rDNA), demonstrating that TAF1B/SL1 is required for stable UBTF1 engagement at rDNA promoters and that UBTF1–SL1 cooperation generates rDNA promoter specificity in an induced-fit mechanism.\",\n      \"method\": \"Conditional TAF1B deletion, ChIP-seq for UBTF at rDNA promoters, quantitative genomic analysis\",\n      \"journal\": \"PLoS genetics\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — conditional gene deletion combined with ChIP-seq showing specific loss of UBTF at promoters; multiple orthogonal methods and strong genetic evidence\",\n      \"pmids\": [\"35139074\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2022,\n      \"finding\": \"In Drosophila, impaired function of TAF1B (a subunit of the SL1-like complex) leads to derepression of R2-retrotransposon-containing rDNA units, accompanied by reduction of H3K9me3 and HP1a marks at those loci, suggesting the SL1-like complex participates in selective activation of intact rDNA units in competition with heterochromatin formation.\",\n      \"method\": \"RNAi knockdown of TAF1B in Drosophila ovaries, ChIP for H3K9me3/HP1a, quantitative RT-PCR of R2 elements\",\n      \"journal\": \"Nucleic acids research\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — genetic knockdown with ChIP validation; single lab, two orthogonal methods\",\n      \"pmids\": [\"35037046\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2023,\n      \"finding\": \"TAF1B depletion in hepatocellular carcinoma cells disrupts the pre-initiation complex (PIC) at rDNA, reduces Pol I binding to rDNA (validated by ChIP), decreases pre-rRNA levels, induces nucleolar stress, and triggers apoptosis via a p53–miR-101 feedback circuit in which Pol I transcription repression activates p53, which induces miR-101, and miR-101 negatively feeds back by inhibiting the p53-mediated PARP pathway.\",\n      \"method\": \"Lentiviral knockdown, Co-IP, ChIP, FISH for rDNA activity, immunofluorescence, xenograft tumor model, Western blot for apoptosis markers\",\n      \"journal\": \"Frontiers in oncology\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — multiple orthogonal methods (ChIP, Co-IP, FISH, xenograft) in single lab; mechanistic pathway defined but some steps inferred\",\n      \"pmids\": [\"37645431\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2023,\n      \"finding\": \"TAF1B knockdown in stomach adenocarcinoma cells disrupts the Pol I pre-initiation complex, impairs rRNA gene transcription and ribosome biogenesis, induces nucleolar stress, and promotes c-MYC mRNA degradation, resulting in inhibition of cell proliferation and survival in vitro and in vivo.\",\n      \"method\": \"RNAi knockdown, in vitro proliferation assay, xenograft model, qRT-PCR for pre-rRNA, Western blot for c-MYC\",\n      \"journal\": \"Heliyon\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — KD with defined cellular and molecular phenotype in vitro and in vivo; single lab, multiple readouts\",\n      \"pmids\": [\"38169774\"],\n      \"is_preprint\": false\n    }\n  ],\n  \"current_model\": \"TAF1B is a subunit of the human RNA Polymerase I basal transcription factor SL1 (Selectivity Factor 1) and is structurally related to TFIIB/TFIIB-like proteins through N-terminal zinc ribbon and cyclin-like fold domains; within SL1 it directly contacts the rDNA promoter, is required for stable UBTF1 engagement at promoters (induced-fit recognition), mediates RRN3-dependent recruitment of transcriptionally active Pol I to the preinitiation complex, and has an essential post-Pol I recruitment role in PIC assembly, such that its depletion reduces rRNA synthesis, triggers nucleolar stress, and—through p53 and c-MYC pathways—induces apoptosis and blocks cell proliferation.\"\n}\n```","stage2_raw":"{\n  \"mechanistic_narrative\": \"TAF1B is a subunit of the human RNA Polymerase I promoter selectivity factor SL1, where it functions as a core component of the basal machinery that drives transcription of ribosomal RNA genes [#0]. Within SL1 it directly contacts rDNA promoter DNA, and the complex stably associates with rRNA gene sites independent of transcriptional state [#0, #1]. TAF1B is structurally related to TFIIB/TFIIB-like initiation factors through predicted N-terminal zinc ribbon and cyclin-like fold domains, an architecture conserved through its yeast ortholog Rrn7, establishing TFIIB-like factors as common initiation components across all three eukaryotic RNA polymerase systems [#6, #7]. Mechanistically, TAF1B interacts directly with the initiation-competent cofactor RRN3 to recruit transcriptionally active Pol I to the rDNA promoter, and it carries an additional essential role in preinitiation complex assembly that follows Pol I recruitment [#2, #6]. SL1 function through TAF1B is also required for stable engagement of UBTF at rRNA gene promoters, generating promoter specificity through an induced-fit mechanism [#11]. Loss of TAF1B collapses the Pol I preinitiation complex, reduces pre-rRNA synthesis, and triggers nucleolar stress that activates p53- and c-MYC-dependent programs to induce apoptosis and block proliferation in cancer cells [#13, #14]. Across model organisms, TAF1B is required for rRNA synthesis supporting germline stem cell proliferation and hematopoietic cell maintenance [#8, #10].\",\n  \"teleology\": [\n    {\n      \"year\": 1995,\n      \"claim\": \"Established TAF1B as a defined subunit of the Pol I selectivity factor SL1 that directly contacts rDNA promoter DNA, identifying its place in the basal rRNA transcription machinery.\",\n      \"evidence\": \"In vitro reconstitution of SL1 with transcription assays and protein-DNA contact mapping\",\n      \"pmids\": [\"7491500\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Atomic structure of TAF1B within SL1 not resolved\", \"Specific promoter DNA bases contacted by TAF1B versus TAFI110 not delineated\"]\n    },\n    {\n      \"year\": 1996,\n      \"claim\": \"Showed SL1 (including TAF1B) remains stably bound to rRNA genes regardless of transcriptional activity, indicating constitutive promoter occupancy rather than activity-dependent recruitment.\",\n      \"evidence\": \"Immunofluorescence colocalization and anti-TBP Co-IP from active and actinomycin D-treated cell extracts\",\n      \"pmids\": [\"8609157\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Single-lab observation\", \"Does not address dynamics of complex turnover\"]\n    },\n    {\n      \"year\": 2001,\n      \"claim\": \"Identified TAF1B as a direct binding partner of the initiation factor RRN3, linking SL1 to recruitment of the transcriptionally active form of Pol I.\",\n      \"evidence\": \"Co-IP, direct interaction assay, and in vitro transcription with interaction-blocking experiments\",\n      \"pmids\": [\"11250903\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Interaction interface on TAF1B not mapped at residue level\", \"How RRN3 binding is regulated remains unaddressed\"]\n    },\n    {\n      \"year\": 2004,\n      \"claim\": \"Characterized TBP-contact and nuclear import surfaces within SL1 TAF subunits, defining how the complex containing TAF1B assembles and localizes, though the mapped determinants reside on the partner TAFI48.\",\n      \"evidence\": \"Yeast two-hybrid, GST pull-down, GFP localization, and site-directed mutagenesis of TBP and TAFI48\",\n      \"pmids\": [\"15113842\", \"15315821\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Determinants mapped on TAFI48, not TAF1B itself\", \"TAF1B's own import and TBP-contact contributions not isolated\"]\n    },\n    {\n      \"year\": 2007,\n      \"claim\": \"Reported a pathogen (Toxoplasma GRA10) interaction with nucleolar TAF1B, indicating TAF1B can be targeted at the nucleolus by exogenous factors.\",\n      \"evidence\": \"Yeast two-hybrid, GST pull-down, Co-IP, and immunofluorescence colocalization\",\n      \"pmids\": [\"17876161\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Functional consequence for host rRNA transcription unknown\", \"Single-lab, non-physiological co-transfection context\"]\n    },\n    {\n      \"year\": 2011,\n      \"claim\": \"Resolved TAF1B as a TFIIB-like factor with zinc ribbon and cyclin-fold domains and an essential post-recruitment role in PIC assembly, unifying initiation mechanisms across the three RNA polymerase systems.\",\n      \"evidence\": \"Structural homology prediction, domain swaps, and functional complementation; corroborated by yeast Rrn7 ortholog analysis\",\n      \"pmids\": [\"21921199\", \"21921198\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Precise step in PIC assembly executed by TAF1B not defined\", \"No experimental high-resolution structure of human TAF1B\"]\n    },\n    {\n      \"year\": 2014,\n      \"claim\": \"Demonstrated through genetic loss-of-function that TAF1B is required for rRNA synthesis supporting germline stem cell proliferation, linking the molecular function to a developmental cellular output.\",\n      \"evidence\": \"Drosophila loss-of-function genetics, rRNA transcription measurement, GSC proliferation assay\",\n      \"pmids\": [\"24436420\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Drosophila complex composition may differ from human SL1\", \"Tissue-specific requirements in mammals not addressed here\"]\n    },\n    {\n      \"year\": 2017,\n      \"claim\": \"Placed TAF1B downstream of Piwi and upstream of Udd in nucleolar recruitment, ordering the SL1-like complex assembly pathway in germline cells.\",\n      \"evidence\": \"RNAi knockdown, immunofluorescence localization, and genetic epistasis in Drosophila\",\n      \"pmids\": [\"29116069\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Molecular basis of TAF1B-dependent Udd recruitment unknown\", \"Conservation of this hierarchy in mammals untested\"]\n    },\n    {\n      \"year\": 2019,\n      \"claim\": \"Showed Taf1b expression is epigenetically controlled by KDM4 demethylases and is essential for hematopoietic cell maintenance, connecting TAF1B regulation to stem cell homeostasis.\",\n      \"evidence\": \"Conditional triple-knockout mice, H3K9me3 ChIP at the Taf1b TSS, expression and rescue analysis\",\n      \"pmids\": [\"31434704\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Direct demonstration that rRNA loss mediates the hematopoietic phenotype not provided\", \"Single-lab finding\"]\n    },\n    {\n      \"year\": 2022,\n      \"claim\": \"Established that TAF1B/SL1 is required for stable UBTF engagement specifically at rRNA gene promoters, defining an induced-fit mechanism generating rDNA promoter specificity.\",\n      \"evidence\": \"Conditional TAF1B deletion with ChIP-seq for UBTF across rDNA\",\n      \"pmids\": [\"35139074\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Structural basis of induced-fit cooperation not resolved\", \"Order of UBTF versus SL1 binding events not fully established\"]\n    },\n    {\n      \"year\": 2022,\n      \"claim\": \"Implicated the TAF1B-containing complex in selective activation of intact rDNA units in competition with heterochromatin, linking SL1 to rDNA copy-number/chromatin regulation.\",\n      \"evidence\": \"Drosophila RNAi knockdown, ChIP for H3K9me3/HP1a, qRT-PCR of R2 retrotransposon elements\",\n      \"pmids\": [\"35037046\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Direct role of TAF1B in chromatin mark deposition versus indirect effect unclear\", \"Mammalian relevance untested\"]\n    },\n    {\n      \"year\": 2023,\n      \"claim\": \"Connected TAF1B-dependent PIC integrity to tumor cell viability, showing depletion collapses Pol I transcription and triggers nucleolar-stress apoptosis via p53/c-MYC pathways.\",\n      \"evidence\": \"Lentiviral/RNAi knockdown, ChIP, Co-IP, FISH, xenograft models, and apoptosis/proliferation readouts in hepatocellular and stomach carcinoma cells\",\n      \"pmids\": [\"37645431\", \"38169774\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Some pathway steps (p53-miR-101 feedback) are inferred rather than directly demonstrated\", \"Single-lab studies per tumor type\"]\n    },\n    {\n      \"year\": null,\n      \"claim\": \"How TAF1B coordinates its sequential RRN3-mediated Pol I recruitment and post-recruitment PIC assembly roles at atomic resolution, and how these are regulated to control rRNA output, remains unresolved.\",\n      \"evidence\": \"\",\n      \"pmids\": [],\n      \"confidence\": \"High\",\n      \"gaps\": [\"No experimental high-resolution structure of human SL1 with TAF1B\", \"Regulatory inputs governing TAF1B activity in human cells undefined\"]\n    }\n  ],\n  \"mechanism_profile\": {\n    \"molecular_activity\": [\n      {\"term_id\": \"GO:0003677\", \"supporting_discovery_ids\": [0]},\n      {\"term_id\": \"GO:0140110\", \"supporting_discovery_ids\": [0, 2, 6]},\n      {\"term_id\": \"GO:0140223\", \"supporting_discovery_ids\": [0, 6]}\n    ],\n    \"localization\": [\n      {\"term_id\": \"GO:0005730\", \"supporting_discovery_ids\": [1, 5, 9]},\n      {\"term_id\": \"GO:0005634\", \"supporting_discovery_ids\": [1]}\n    ],\n    \"pathway\": [\n      {\"term_id\": \"R-HSA-74160\", \"supporting_discovery_ids\": [0, 2, 6, 11]},\n      {\"term_id\": \"R-HSA-8953854\", \"supporting_discovery_ids\": [8, 14]},\n      {\"term_id\": \"R-HSA-5357801\", \"supporting_discovery_ids\": [13]}\n    ],\n    \"complexes\": [\"SL1 (Selectivity Factor 1)\", \"RNA Pol I core factor (yeast Rrn7)\"],\n    \"partners\": [\"TBP\", \"RRN3\", \"TAF1A\", \"TAF1C\", \"UBTF\"],\n    \"other_free_text\": []\n  }\n}","audit_flag":null,"evaluation":{"pairwise":"win","faith_supported":7,"faith_total":7,"faith_pct":100.0}}