{"gene":"ANKRD54","run_date":"2026-04-28T17:12:37","timeline":{"discoveries":[{"year":2008,"finding":"ANKRD54 (Liar) was identified as a novel Lyn-binding protein that forms a multiprotein complex with Lyn and HS1 in erythroid cells. Three ankyrin repeats of Liar define a novel SH3 binding region for Lyn and HS1. Liar contains functional nuclear localization and nuclear export sequences, shuttles rapidly between the nucleus and cytoplasm, and its ectopic expression inhibited erythroid differentiation while affecting Epo-activated signaling molecules including Erk2, STAT5, Akt, and Lyn.","method":"Yeast two-hybrid screen, co-immunoprecipitation, nuclear localization/export sequence functional analysis, live cell imaging of shuttling, ectopic expression with erythroid differentiation assays","journal":"Blood","confidence":"High","confidence_rationale":"Tier 2 — multiple orthogonal methods (Y2H, Co-IP, functional localization, loss/gain-of-function with defined phenotypic readout)","pmids":["19064729"],"is_preprint":false},{"year":2012,"finding":"ANKRD54 (Liar) interacts with Bruton's tyrosine kinase (Btk) via an SH3-dependent mechanism and mediates nuclear export of both Btk and Txk/Rlk. The interaction is enriched for non-phosphorylated (activation loop) Btk, is entirely dependent on Btk's SH3 domain, and is reduced by an aspartic acid phosphomimetic SH3 mutant. The interaction site was mapped to the C terminus of the Btk SH3 domain (peptide ARDKNGQEGYIPSNYVTEAEDS). Three other nucleus-located proteins (Abl, ERβ, T-bet) were unaffected by Liar. Liar itself shuttles at a higher rate than Btk, and shuttling is Crm1-dependent.","method":"Affinity purification with Flag-tagged Btk + tandem mass spectrometry, co-immunoprecipitation, domain mapping with synthetic biotinylated peptide, Crm1 inhibition assays, phosphomimetic SH3 mutagenesis, live cell nucleocytoplasmic shuttling assays","journal":"Molecular and cellular biology","confidence":"High","confidence_rationale":"Tier 1-2 — multiple orthogonal methods including MS-based interactome, mutagenesis, peptide mapping, and functional shuttling assays in a single rigorous study","pmids":["22527282"],"is_preprint":false},{"year":2017,"finding":"ANKRD54 preferentially and specifically interacts with the BTK SH3 domain among all 296 human SH3 domains, as determined by phage-display screening of a comprehensive human SH3 domain library, confirmed by quantitative western blotting.","method":"Phage-display screening of complete human SH3 domain library (296 domains), quantitative western blotting validation","journal":"PloS one","confidence":"High","confidence_rationale":"Tier 1-2 — comprehensive unbiased library screen with orthogonal quantitative validation, demonstrating selectivity of interaction","pmids":["28369144"],"is_preprint":false},{"year":2017,"finding":"PKCδ phosphorylates ANKRD54 and promotes its cytoplasmic localization (nuclear export). PMA-induced PKC activation increased ANKRD54 phosphorylation and cytoplasmic localization. Alanine mutation of Ser14, Ser17, Ser18, Ser19 in the amino-terminal region reduced both PMA-induced cytoplasmic localization and phosphorylation. MRM proteomic analysis confirmed phosphorylation of Ser18 in response to PMA. Co-expression of active PKCδ specifically promoted phosphorylation and cytoplasmic localization, while PKCδ (inactive), Akt, and PKA did not. PMA stimulation enhanced co-immunoprecipitation and co-localization of ANKRD54 with Lyn in the cytoplasm.","method":"Immunofluorescence imaging, subcellular fractionation immunoblotting, Phos-tag gel retardation, MRM proteomic analysis, site-directed alanine mutagenesis, co-immunoprecipitation, active kinase overexpression","journal":"World journal of biological chemistry","confidence":"High","confidence_rationale":"Tier 1-2 — multiple orthogonal methods including mutagenesis, MS-based phosphosite mapping, and functional localization assays in one study","pmids":["28924458"],"is_preprint":false}],"current_model":"ANKRD54 (Liar) is a nucleocytoplasmic shuttling protein that preferentially binds the SH3 domains of Btk and Lyn via its ankyrin repeat domain, mediates Crm1-dependent nuclear export of Btk and Txk/Rlk (but not Abl, ERβ, or T-bet), with its subcellular localization and interaction with Lyn regulated by PKCδ-mediated phosphorylation at Ser18 (and nearby residues) in its amino-terminal region, while its interaction with Btk is selective for non-phosphorylated (inactive) Btk."},"narrative":{"teleology":[{"year":2008,"claim":"The discovery that ANKRD54 is a Lyn-binding nucleocytoplasmic shuttling protein with functional NLS/NES established it as a novel adaptor linking SH3-mediated kinase interactions to nuclear-cytoplasmic trafficking and erythroid differentiation signaling.","evidence":"Yeast two-hybrid screen, co-immunoprecipitation, live-cell shuttling imaging, and ectopic expression in erythroid differentiation assays","pmids":["19064729"],"confidence":"High","gaps":["Mechanism by which ANKRD54 inhibits erythroid differentiation not resolved at molecular level","Whether ANKRD54 shuttling is functionally required for its effects on Epo signaling not tested","Identity of kinase(s) regulating ANKRD54 localization unknown at this point"]},{"year":2012,"claim":"Demonstrating that ANKRD54 directly exports Btk and Txk/Rlk from the nucleus via a Crm1-dependent mechanism—while selectively binding non-phosphorylated Btk SH3—resolved ANKRD54's role as a cargo-specific nuclear export adaptor for Tec-family kinases.","evidence":"Flag-Btk affinity purification with tandem MS, domain mapping with synthetic peptides, phosphomimetic SH3 mutagenesis, and Crm1 inhibition assays","pmids":["22527282"],"confidence":"High","gaps":["Physiological consequence of Btk/Txk nuclear export by ANKRD54 on downstream signaling not established","Whether ANKRD54 acts catalytically (shuttling multiple Btk molecules) or stoichiometrically not determined","Structural basis of the ankyrin-repeat–SH3 interaction unresolved"]},{"year":2017,"claim":"Comprehensive screening of all 296 human SH3 domains confirmed that ANKRD54 is a uniquely selective Btk SH3 binder, establishing the exceptional specificity of this adaptor interaction within the SH3 interactome.","evidence":"Phage-display screening of complete human SH3 domain library with quantitative western blot validation","pmids":["28369144"],"confidence":"High","gaps":["Affinity constants for the ANKRD54–Btk SH3 interaction not quantified","Whether the selectivity extends to all Tec-family SH3 domains not fully tested"]},{"year":2017,"claim":"Identification of PKCδ as the kinase that phosphorylates ANKRD54 at Ser18 to drive its cytoplasmic retention and enhanced Lyn interaction resolved the upstream signal controlling ANKRD54 subcellular distribution.","evidence":"Phos-tag gel retardation, MRM phosphoproteomics, site-directed alanine mutagenesis, immunofluorescence, and co-immunoprecipitation with active PKCδ overexpression","pmids":["28924458"],"confidence":"High","gaps":["Whether PKCδ-mediated phosphorylation also affects ANKRD54–Btk interaction or Btk nuclear export not tested","Phosphatase responsible for ANKRD54 dephosphorylation not identified","In vivo relevance of PKCδ-ANKRD54 axis in hematopoietic cells not demonstrated"]},{"year":null,"claim":"The physiological requirement for ANKRD54 in vivo—including its role in immune cell signaling, erythropoiesis, and potential disease relevance—remains uncharacterized, as does the structural basis of its ankyrin-repeat–SH3 interaction.","evidence":"","pmids":[],"confidence":"Low","gaps":["No knockout or knockdown studies in animal models reported","No structural model (crystal or cryo-EM) of the ankyrin-repeat–SH3 complex","Functional interplay between PKCδ phosphorylation and Btk export activity not addressed"]}],"mechanism_profile":{"molecular_activity":[{"term_id":"GO:0060090","term_label":"molecular adaptor activity","supporting_discovery_ids":[0,1,2]}],"localization":[{"term_id":"GO:0005634","term_label":"nucleus","supporting_discovery_ids":[0,1,3]},{"term_id":"GO:0005829","term_label":"cytosol","supporting_discovery_ids":[0,1,3]}],"pathway":[{"term_id":"R-HSA-162582","term_label":"Signal Transduction","supporting_discovery_ids":[0,3]}],"complexes":[],"partners":["LYN","BTK","HCLS1","TXK","PRKCD"],"other_free_text":[]},"mechanistic_narrative":"ANKRD54 (Liar) is a nucleocytoplasmic shuttling protein that functions as a selective SH3-domain-binding adaptor mediating Crm1-dependent nuclear export of specific signaling kinases. Its ankyrin repeat domain defines a novel SH3-binding interface that preferentially engages the SH3 domains of Btk and Lyn—with Btk SH3 selectivity confirmed across all 296 human SH3 domains—and it facilitates nuclear export of Btk and Txk/Rlk but not other nuclear proteins such as Abl, ERβ, or T-bet [PMID:22527282, PMID:28369144]. PKCδ-mediated phosphorylation at Ser18 and neighboring N-terminal residues drives ANKRD54 cytoplasmic accumulation and enhances its co-localization and interaction with Lyn, linking kinase signaling to ANKRD54 subcellular distribution [PMID:28924458]. In erythroid cells, ANKRD54 forms a complex with Lyn and HS1, and its ectopic expression inhibits erythroid differentiation while modulating Epo-activated signaling through Erk2, STAT5, Akt, and Lyn [PMID:19064729]."},"prefetch_data":{"uniprot":{"accession":"Q6NXT1","full_name":"Ankyrin repeat domain-containing protein 54","aliases":["Lyn-interacting ankyrin repeat protein"],"length_aa":300,"mass_kda":32.5,"function":"Plays an important role in regulating intracellular signaling events associated with erythroid terminal differentiation","subcellular_location":"Nucleus; Cytoplasm; Midbody","url":"https://www.uniprot.org/uniprotkb/Q6NXT1/entry"},"depmap":{"release":"DepMap","has_data":true,"is_common_essential":false,"resolved_as":"","url":"https://depmap.org/portal/gene/ANKRD54","classification":"Not Classified","n_dependent_lines":29,"n_total_lines":1208,"dependency_fraction":0.024006622516556293},"opencell":{"profiled":true,"resolved_as":"","ensg_id":"ENSG00000100124","cell_line_id":"CID001926","localizations":[{"compartment":"nucleoplasm","grade":3},{"compartment":"nuclear_punctae","grade":2}],"interactors":[{"gene":"HNRNPUL2-BSCL2;HNRNPUL2","stoichiometry":4.0},{"gene":"SNX33","stoichiometry":0.2},{"gene":"FAM192A;NIP30","stoichiometry":0.2},{"gene":"KIAA1279","stoichiometry":0.2},{"gene":"DOCK1","stoichiometry":0.2},{"gene":"KPNA2","stoichiometry":0.2},{"gene":"PSME3","stoichiometry":0.2},{"gene":"TULP3","stoichiometry":0.2},{"gene":"CSNK2A2","stoichiometry":0.2}],"url":"https://opencell.sf.czbiohub.org/target/CID001926","total_profiled":1310},"omim":[{"mim_id":"613383","title":"ANKYRIN REPEAT DOMAIN-CONTAINING PROTEIN 54; ANKRD54","url":"https://www.omim.org/entry/613383"}],"hpa":{"profiled":true,"resolved_as":"","reliability":"Approved","locations":[{"location":"Microtubules","reliability":"Approved"},{"location":"Midbody","reliability":"Approved"},{"location":"Nucleoplasm","reliability":"Additional"}],"tissue_specificity":"Low tissue specificity","tissue_distribution":"Detected in all","driving_tissues":[],"url":"https://www.proteinatlas.org/search/ANKRD54"},"hgnc":{"alias_symbol":["LIAR"],"prev_symbol":[]},"alphafold":{"accession":"Q6NXT1","domains":[{"cath_id":"1.25.40.20","chopping":"106-205","consensus_level":"medium","plddt":91.3023,"start":106,"end":205},{"cath_id":"-","chopping":"212-300","consensus_level":"medium","plddt":76.806,"start":212,"end":300}],"viewer_url":"https://alphafold.ebi.ac.uk/entry/Q6NXT1","model_url":"https://alphafold.ebi.ac.uk/files/AF-Q6NXT1-F1-model_v6.cif","pae_url":"https://alphafold.ebi.ac.uk/files/AF-Q6NXT1-F1-predicted_aligned_error_v6.png","plddt_mean":68.38},"mouse_models":{"mgi_url":"https://www.informatics.jax.org/marker/summary?nomen=ANKRD54","jax_strain_url":"https://www.jax.org/strain/search?query=ANKRD54"},"sequence":{"accession":"Q6NXT1","fasta_url":"https://rest.uniprot.org/uniprotkb/Q6NXT1.fasta","uniprot_url":"https://www.uniprot.org/uniprotkb/Q6NXT1/entry","alphafold_viewer_url":"https://alphafold.ebi.ac.uk/entry/Q6NXT1"}},"corpus_meta":[{"pmid":"20447076","id":"PMC_20447076","title":"Eosinophils in health and disease: the LIAR hypothesis.","date":"2010","source":"Clinical and experimental allergy : journal of the British Society for Allergy and Clinical Immunology","url":"https://pubmed.ncbi.nlm.nih.gov/20447076","citation_count":267,"is_preprint":false},{"pmid":"20639339","id":"PMC_20639339","title":"In-depth profiling of the LiaR response of Bacillus subtilis.","date":"2010","source":"Journal of bacteriology","url":"https://pubmed.ncbi.nlm.nih.gov/20639339","citation_count":100,"is_preprint":false},{"pmid":"25362197","id":"PMC_25362197","title":"A liaR deletion restores susceptibility to daptomycin and antimicrobial peptides in multidrug-resistant Enterococcus faecalis.","date":"2014","source":"The Journal of infectious diseases","url":"https://pubmed.ncbi.nlm.nih.gov/25362197","citation_count":79,"is_preprint":false},{"pmid":"23851083","id":"PMC_23851083","title":"Nisin resistance of Listeria monocytogenes is increased by exposure to salt stress and is mediated via LiaR.","date":"2013","source":"Applied and environmental microbiology","url":"https://pubmed.ncbi.nlm.nih.gov/23851083","citation_count":68,"is_preprint":false},{"pmid":"23704792","id":"PMC_23704792","title":"The two-component response regulator LiaR regulates cell wall stress responses, pili expression and virulence in group B Streptococcus.","date":"2013","source":"Microbiology (Reading, England)","url":"https://pubmed.ncbi.nlm.nih.gov/23704792","citation_count":51,"is_preprint":false},{"pmid":"21128282","id":"PMC_21128282","title":"LRIG1 and the liar paradox in prostate cancer: a study of the expression and clinical significance of LRIG1 in prostate cancer.","date":"2011","source":"International journal of cancer","url":"https://pubmed.ncbi.nlm.nih.gov/21128282","citation_count":39,"is_preprint":false},{"pmid":"27208105","id":"PMC_27208105","title":"Exogenous Fatty Acids Protect Enterococcus faecalis from Daptomycin-Induced Membrane Stress Independently of the Response Regulator LiaR.","date":"2016","source":"Applied and environmental microbiology","url":"https://pubmed.ncbi.nlm.nih.gov/27208105","citation_count":38,"is_preprint":false},{"pmid":"25897118","id":"PMC_25897118","title":"A variable DNA recognition site organization establishes the LiaR-mediated cell envelope stress response of enterococci to daptomycin.","date":"2015","source":"Nucleic acids research","url":"https://pubmed.ncbi.nlm.nih.gov/25897118","citation_count":37,"is_preprint":false},{"pmid":"26369959","id":"PMC_26369959","title":"Deletion of liaR Reverses Daptomycin Resistance in Enterococcus faecium Independent of the Genetic Background.","date":"2015","source":"Antimicrobial agents and chemotherapy","url":"https://pubmed.ncbi.nlm.nih.gov/26369959","citation_count":36,"is_preprint":false},{"pmid":"30582877","id":"PMC_30582877","title":"LiaR-independent pathways to daptomycin resistance in Enterococcus faecalis reveal a multilayer defense against cell envelope antibiotics.","date":"2019","source":"Molecular microbiology","url":"https://pubmed.ncbi.nlm.nih.gov/30582877","citation_count":30,"is_preprint":false},{"pmid":"27670715","id":"PMC_27670715","title":"An Adaptive Mutation in Enterococcus faecium LiaR Associated with Antimicrobial Peptide Resistance Mimics Phosphorylation and Stabilizes LiaR in an Activated State.","date":"2016","source":"Journal of molecular biology","url":"https://pubmed.ncbi.nlm.nih.gov/27670715","citation_count":24,"is_preprint":false},{"pmid":"22527282","id":"PMC_22527282","title":"Regulation of nucleocytoplasmic shuttling of Bruton's tyrosine kinase (Btk) through a novel SH3-dependent interaction with ankyrin repeat domain 54 (ANKRD54).","date":"2012","source":"Molecular and cellular biology","url":"https://pubmed.ncbi.nlm.nih.gov/22527282","citation_count":20,"is_preprint":false},{"pmid":"19064729","id":"PMC_19064729","title":"Liar, a novel Lyn-binding nuclear/cytoplasmic shuttling protein that influences erythropoietin-induced differentiation.","date":"2008","source":"Blood","url":"https://pubmed.ncbi.nlm.nih.gov/19064729","citation_count":16,"is_preprint":false},{"pmid":"19722183","id":"PMC_19722183","title":"Gene networks and liar paradoxes.","date":"2009","source":"BioEssays : news and reviews in molecular, cellular and developmental biology","url":"https://pubmed.ncbi.nlm.nih.gov/19722183","citation_count":14,"is_preprint":false},{"pmid":"32043713","id":"PMC_32043713","title":"Streptococcus mutans SpxA2 relays the signal of cell envelope stress from LiaR to effectors that maintain cell wall and membrane homeostasis.","date":"2020","source":"Molecular oral microbiology","url":"https://pubmed.ncbi.nlm.nih.gov/32043713","citation_count":14,"is_preprint":false},{"pmid":"30403130","id":"PMC_30403130","title":"Two Mutations Commonly Associated with Daptomycin Resistance in Enterococcus faecium LiaST120A and LiaRW73C Appear To Function Epistatically in LiaFSR Signaling.","date":"2018","source":"Biochemistry","url":"https://pubmed.ncbi.nlm.nih.gov/30403130","citation_count":11,"is_preprint":false},{"pmid":"34168597","id":"PMC_34168597","title":"Catching a Liar Through Facial Expression of Fear.","date":"2021","source":"Frontiers in psychology","url":"https://pubmed.ncbi.nlm.nih.gov/34168597","citation_count":6,"is_preprint":false},{"pmid":"32349670","id":"PMC_32349670","title":"Low phosphatase activity of LiaS and strong LiaR-DNA affinity explain the unusual LiaS to LiaR in vivo stoichiometry.","date":"2020","source":"BMC microbiology","url":"https://pubmed.ncbi.nlm.nih.gov/32349670","citation_count":6,"is_preprint":false},{"pmid":"25308550","id":"PMC_25308550","title":"A Streptococcus uberis transposon mutant screen reveals a negative role for LiaR homologue in biofilm formation.","date":"2014","source":"Journal of applied 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chemistry","url":"https://pubmed.ncbi.nlm.nih.gov/28924458","citation_count":0,"is_preprint":false},{"pmid":null,"id":"bio_10.1101_2025.06.19.660511","title":"LiaS-dependent activation of the MadR regulon enables cross-talk between <i>Enterococcus faecalis</i> cell envelope defense systems","date":"2025-06-20","source":"bioRxiv","url":"https://doi.org/10.1101/2025.06.19.660511","citation_count":0,"is_preprint":true},{"pmid":null,"id":"bio_10.1101_2024.10.30.621020","title":"Genome-wide antibiotic-CRISPRi profiling identifies LiaR activation as a strategy to resensitize fluoroquinolone-resistant  <i>Streptococcus pneumoniae</i>","date":"2024-10-30","source":"bioRxiv","url":"https://doi.org/10.1101/2024.10.30.621020","citation_count":0,"is_preprint":true}],"cost":{"stage1":{"model":"claude-sonnet-4-6","input_tokens":13643,"output_tokens":1426,"usd":0.031159},"stage2":{"model":"claude-opus-4-6","input_tokens":4648,"output_tokens":3413,"usd":0.162848},"total_usd":0.194007,"stage1_batch_id":"msgbatch_01TqNM6p6FsoMBT2jzQTwKBr","stage2_batch_id":"msgbatch_01Ya473eco8sTHbvRymQaU8o","note":"batch pricing = 50% of standard"},"stage1_raw":"```json\n{\n  \"discoveries\": [\n    {\n      \"year\": 2008,\n      \"finding\": \"ANKRD54 (Liar) was identified as a novel Lyn-binding protein that forms a multiprotein complex with Lyn and HS1 in erythroid cells. Three ankyrin repeats of Liar define a novel SH3 binding region for Lyn and HS1. Liar contains functional nuclear localization and nuclear export sequences, shuttles rapidly between the nucleus and cytoplasm, and its ectopic expression inhibited erythroid differentiation while affecting Epo-activated signaling molecules including Erk2, STAT5, Akt, and Lyn.\",\n      \"method\": \"Yeast two-hybrid screen, co-immunoprecipitation, nuclear localization/export sequence functional analysis, live cell imaging of shuttling, ectopic expression with erythroid differentiation assays\",\n      \"journal\": \"Blood\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 — multiple orthogonal methods (Y2H, Co-IP, functional localization, loss/gain-of-function with defined phenotypic readout)\",\n      \"pmids\": [\"19064729\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2012,\n      \"finding\": \"ANKRD54 (Liar) interacts with Bruton's tyrosine kinase (Btk) via an SH3-dependent mechanism and mediates nuclear export of both Btk and Txk/Rlk. The interaction is enriched for non-phosphorylated (activation loop) Btk, is entirely dependent on Btk's SH3 domain, and is reduced by an aspartic acid phosphomimetic SH3 mutant. The interaction site was mapped to the C terminus of the Btk SH3 domain (peptide ARDKNGQEGYIPSNYVTEAEDS). Three other nucleus-located proteins (Abl, ERβ, T-bet) were unaffected by Liar. Liar itself shuttles at a higher rate than Btk, and shuttling is Crm1-dependent.\",\n      \"method\": \"Affinity purification with Flag-tagged Btk + tandem mass spectrometry, co-immunoprecipitation, domain mapping with synthetic biotinylated peptide, Crm1 inhibition assays, phosphomimetic SH3 mutagenesis, live cell nucleocytoplasmic shuttling assays\",\n      \"journal\": \"Molecular and cellular biology\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1-2 — multiple orthogonal methods including MS-based interactome, mutagenesis, peptide mapping, and functional shuttling assays in a single rigorous study\",\n      \"pmids\": [\"22527282\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2017,\n      \"finding\": \"ANKRD54 preferentially and specifically interacts with the BTK SH3 domain among all 296 human SH3 domains, as determined by phage-display screening of a comprehensive human SH3 domain library, confirmed by quantitative western blotting.\",\n      \"method\": \"Phage-display screening of complete human SH3 domain library (296 domains), quantitative western blotting validation\",\n      \"journal\": \"PloS one\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1-2 — comprehensive unbiased library screen with orthogonal quantitative validation, demonstrating selectivity of interaction\",\n      \"pmids\": [\"28369144\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2017,\n      \"finding\": \"PKCδ phosphorylates ANKRD54 and promotes its cytoplasmic localization (nuclear export). PMA-induced PKC activation increased ANKRD54 phosphorylation and cytoplasmic localization. Alanine mutation of Ser14, Ser17, Ser18, Ser19 in the amino-terminal region reduced both PMA-induced cytoplasmic localization and phosphorylation. MRM proteomic analysis confirmed phosphorylation of Ser18 in response to PMA. Co-expression of active PKCδ specifically promoted phosphorylation and cytoplasmic localization, while PKCδ (inactive), Akt, and PKA did not. PMA stimulation enhanced co-immunoprecipitation and co-localization of ANKRD54 with Lyn in the cytoplasm.\",\n      \"method\": \"Immunofluorescence imaging, subcellular fractionation immunoblotting, Phos-tag gel retardation, MRM proteomic analysis, site-directed alanine mutagenesis, co-immunoprecipitation, active kinase overexpression\",\n      \"journal\": \"World journal of biological chemistry\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1-2 — multiple orthogonal methods including mutagenesis, MS-based phosphosite mapping, and functional localization assays in one study\",\n      \"pmids\": [\"28924458\"],\n      \"is_preprint\": false\n    }\n  ],\n  \"current_model\": \"ANKRD54 (Liar) is a nucleocytoplasmic shuttling protein that preferentially binds the SH3 domains of Btk and Lyn via its ankyrin repeat domain, mediates Crm1-dependent nuclear export of Btk and Txk/Rlk (but not Abl, ERβ, or T-bet), with its subcellular localization and interaction with Lyn regulated by PKCδ-mediated phosphorylation at Ser18 (and nearby residues) in its amino-terminal region, while its interaction with Btk is selective for non-phosphorylated (inactive) Btk.\"\n}\n```","stage2_raw":"```json\n{\n  \"mechanistic_narrative\": \"ANKRD54 (Liar) is a nucleocytoplasmic shuttling protein that functions as a selective SH3-domain-binding adaptor mediating Crm1-dependent nuclear export of specific signaling kinases. Its ankyrin repeat domain defines a novel SH3-binding interface that preferentially engages the SH3 domains of Btk and Lyn—with Btk SH3 selectivity confirmed across all 296 human SH3 domains—and it facilitates nuclear export of Btk and Txk/Rlk but not other nuclear proteins such as Abl, ERβ, or T-bet [PMID:22527282, PMID:28369144]. PKCδ-mediated phosphorylation at Ser18 and neighboring N-terminal residues drives ANKRD54 cytoplasmic accumulation and enhances its co-localization and interaction with Lyn, linking kinase signaling to ANKRD54 subcellular distribution [PMID:28924458]. In erythroid cells, ANKRD54 forms a complex with Lyn and HS1, and its ectopic expression inhibits erythroid differentiation while modulating Epo-activated signaling through Erk2, STAT5, Akt, and Lyn [PMID:19064729].\",\n  \"teleology\": [\n    {\n      \"year\": 2008,\n      \"claim\": \"The discovery that ANKRD54 is a Lyn-binding nucleocytoplasmic shuttling protein with functional NLS/NES established it as a novel adaptor linking SH3-mediated kinase interactions to nuclear-cytoplasmic trafficking and erythroid differentiation signaling.\",\n      \"evidence\": \"Yeast two-hybrid screen, co-immunoprecipitation, live-cell shuttling imaging, and ectopic expression in erythroid differentiation assays\",\n      \"pmids\": [\"19064729\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\n        \"Mechanism by which ANKRD54 inhibits erythroid differentiation not resolved at molecular level\",\n        \"Whether ANKRD54 shuttling is functionally required for its effects on Epo signaling not tested\",\n        \"Identity of kinase(s) regulating ANKRD54 localization unknown at this point\"\n      ]\n    },\n    {\n      \"year\": 2012,\n      \"claim\": \"Demonstrating that ANKRD54 directly exports Btk and Txk/Rlk from the nucleus via a Crm1-dependent mechanism—while selectively binding non-phosphorylated Btk SH3—resolved ANKRD54's role as a cargo-specific nuclear export adaptor for Tec-family kinases.\",\n      \"evidence\": \"Flag-Btk affinity purification with tandem MS, domain mapping with synthetic peptides, phosphomimetic SH3 mutagenesis, and Crm1 inhibition assays\",\n      \"pmids\": [\"22527282\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\n        \"Physiological consequence of Btk/Txk nuclear export by ANKRD54 on downstream signaling not established\",\n        \"Whether ANKRD54 acts catalytically (shuttling multiple Btk molecules) or stoichiometrically not determined\",\n        \"Structural basis of the ankyrin-repeat–SH3 interaction unresolved\"\n      ]\n    },\n    {\n      \"year\": 2017,\n      \"claim\": \"Comprehensive screening of all 296 human SH3 domains confirmed that ANKRD54 is a uniquely selective Btk SH3 binder, establishing the exceptional specificity of this adaptor interaction within the SH3 interactome.\",\n      \"evidence\": \"Phage-display screening of complete human SH3 domain library with quantitative western blot validation\",\n      \"pmids\": [\"28369144\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\n        \"Affinity constants for the ANKRD54–Btk SH3 interaction not quantified\",\n        \"Whether the selectivity extends to all Tec-family SH3 domains not fully tested\"\n      ]\n    },\n    {\n      \"year\": 2017,\n      \"claim\": \"Identification of PKCδ as the kinase that phosphorylates ANKRD54 at Ser18 to drive its cytoplasmic retention and enhanced Lyn interaction resolved the upstream signal controlling ANKRD54 subcellular distribution.\",\n      \"evidence\": \"Phos-tag gel retardation, MRM phosphoproteomics, site-directed alanine mutagenesis, immunofluorescence, and co-immunoprecipitation with active PKCδ overexpression\",\n      \"pmids\": [\"28924458\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\n        \"Whether PKCδ-mediated phosphorylation also affects ANKRD54–Btk interaction or Btk nuclear export not tested\",\n        \"Phosphatase responsible for ANKRD54 dephosphorylation not identified\",\n        \"In vivo relevance of PKCδ-ANKRD54 axis in hematopoietic cells not demonstrated\"\n      ]\n    },\n    {\n      \"year\": null,\n      \"claim\": \"The physiological requirement for ANKRD54 in vivo—including its role in immune cell signaling, erythropoiesis, and potential disease relevance—remains uncharacterized, as does the structural basis of its ankyrin-repeat–SH3 interaction.\",\n      \"evidence\": \"\",\n      \"pmids\": [],\n      \"confidence\": \"Low\",\n      \"gaps\": [\n        \"No knockout or knockdown studies in animal models reported\",\n        \"No structural model (crystal or cryo-EM) of the ankyrin-repeat–SH3 complex\",\n        \"Functional interplay between PKCδ phosphorylation and Btk export activity not addressed\"\n      ]\n    }\n  ],\n  \"mechanism_profile\": {\n    \"molecular_activity\": [\n      {\"term_id\": \"GO:0060090\", \"supporting_discovery_ids\": [0, 1, 2]}\n    ],\n    \"localization\": [\n      {\"term_id\": \"GO:0005634\", \"supporting_discovery_ids\": [0, 1, 3]},\n      {\"term_id\": \"GO:0005829\", \"supporting_discovery_ids\": [0, 1, 3]}\n    ],\n    \"pathway\": [\n      {\"term_id\": \"GO:0009609507\", \"supporting_discovery_ids\": [1, 3]},\n      {\"term_id\": \"R-HSA-162582\", \"supporting_discovery_ids\": [0, 3]}\n    ],\n    \"complexes\": [],\n    \"partners\": [\"LYN\", \"BTK\", \"HCLS1\", \"TXK\", \"PRKCD\"],\n    \"other_free_text\": []\n  }\n}\n```\n\nWait, I need to fix the pathway entry. \"GO:0009609507\" is not a valid term_id. Let me correct:\n\n```json\n{\n  \"mechanistic_narrative\": \"ANKRD54 (Liar) is a nucleocytoplasmic shuttling protein that functions as a selective SH3-domain-binding adaptor mediating Crm1-dependent nuclear export of specific signaling kinases. Its ankyrin repeat domain defines a novel SH3-binding interface that preferentially engages the SH3 domains of Btk and Lyn—with Btk SH3 selectivity confirmed across all 296 human SH3 domains—and it facilitates nuclear export of Btk and Txk/Rlk but not other nuclear proteins such as Abl, ERβ, or T-bet [PMID:22527282, PMID:28369144]. PKCδ-mediated phosphorylation at Ser18 and neighboring N-terminal residues drives ANKRD54 cytoplasmic accumulation and enhances its co-localization and interaction with Lyn, linking kinase signaling to ANKRD54 subcellular distribution [PMID:28924458]. In erythroid cells, ANKRD54 forms a complex with Lyn and HS1, and its ectopic expression inhibits erythroid differentiation while modulating Epo-activated signaling through Erk2, STAT5, Akt, and Lyn [PMID:19064729].\",\n  \"teleology\": [\n    {\n      \"year\": 2008,\n      \"claim\": \"The discovery that ANKRD54 is a Lyn-binding nucleocytoplasmic shuttling protein with functional NLS/NES established it as a novel adaptor linking SH3-mediated kinase interactions to nuclear-cytoplasmic trafficking and erythroid differentiation signaling.\",\n      \"evidence\": \"Yeast two-hybrid screen, co-immunoprecipitation, live-cell shuttling imaging, and ectopic expression in erythroid differentiation assays\",\n      \"pmids\": [\"19064729\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\n        \"Mechanism by which ANKRD54 inhibits erythroid differentiation not resolved at molecular level\",\n        \"Whether ANKRD54 shuttling is functionally required for its effects on Epo signaling not tested\",\n        \"Identity of kinase(s) regulating ANKRD54 localization unknown at this point\"\n      ]\n    },\n    {\n      \"year\": 2012,\n      \"claim\": \"Demonstrating that ANKRD54 directly exports Btk and Txk/Rlk from the nucleus via a Crm1-dependent mechanism—while selectively binding non-phosphorylated Btk SH3—resolved ANKRD54's role as a cargo-specific nuclear export adaptor for Tec-family kinases.\",\n      \"evidence\": \"Flag-Btk affinity purification with tandem MS, domain mapping with synthetic peptides, phosphomimetic SH3 mutagenesis, and Crm1 inhibition assays\",\n      \"pmids\": [\"22527282\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\n        \"Physiological consequence of Btk/Txk nuclear export by ANKRD54 on downstream signaling not established\",\n        \"Whether ANKRD54 acts catalytically (shuttling multiple Btk molecules) or stoichiometrically not determined\",\n        \"Structural basis of the ankyrin-repeat–SH3 interaction unresolved\"\n      ]\n    },\n    {\n      \"year\": 2017,\n      \"claim\": \"Comprehensive screening of all 296 human SH3 domains confirmed that ANKRD54 is a uniquely selective Btk SH3 binder, establishing the exceptional specificity of this adaptor interaction within the SH3 interactome.\",\n      \"evidence\": \"Phage-display screening of complete human SH3 domain library with quantitative western blot validation\",\n      \"pmids\": [\"28369144\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\n        \"Affinity constants for the ANKRD54–Btk SH3 interaction not quantified\",\n        \"Whether the selectivity extends to all Tec-family SH3 domains not fully tested\"\n      ]\n    },\n    {\n      \"year\": 2017,\n      \"claim\": \"Identification of PKCδ as the kinase that phosphorylates ANKRD54 at Ser18 to drive its cytoplasmic retention and enhanced Lyn interaction resolved the upstream signal controlling ANKRD54 subcellular distribution.\",\n      \"evidence\": \"Phos-tag gel retardation, MRM phosphoproteomics, site-directed alanine mutagenesis, immunofluorescence, and co-immunoprecipitation with active PKCδ overexpression\",\n      \"pmids\": [\"28924458\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\n        \"Whether PKCδ-mediated phosphorylation also affects ANKRD54–Btk interaction or Btk nuclear export not tested\",\n        \"Phosphatase responsible for ANKRD54 dephosphorylation not identified\",\n        \"In vivo relevance of PKCδ-ANKRD54 axis in hematopoietic cells not demonstrated\"\n      ]\n    },\n    {\n      \"year\": null,\n      \"claim\": \"The physiological requirement for ANKRD54 in vivo—including its role in immune cell signaling, erythropoiesis, and potential disease relevance—remains uncharacterized, as does the structural basis of its ankyrin-repeat–SH3 interaction.\",\n      \"evidence\": \"\",\n      \"pmids\": [],\n      \"confidence\": \"Low\",\n      \"gaps\": [\n        \"No knockout or knockdown studies in animal models reported\",\n        \"No structural model (crystal or cryo-EM) of the ankyrin-repeat–SH3 complex\",\n        \"Functional interplay between PKCδ phosphorylation and Btk export activity not addressed\"\n      ]\n    }\n  ],\n  \"mechanism_profile\": {\n    \"molecular_activity\": [\n      {\"term_id\": \"GO:0060090\", \"supporting_discovery_ids\": [0, 1, 2]}\n    ],\n    \"localization\": [\n      {\"term_id\": \"GO:0005634\", \"supporting_discovery_ids\": [0, 1, 3]},\n      {\"term_id\": \"GO:0005829\", \"supporting_discovery_ids\": [0, 1, 3]}\n    ],\n    \"pathway\": [\n      {\"term_id\": \"R-HSA-9609507\", \"supporting_discovery_ids\": [1, 3]},\n      {\"term_id\": \"R-HSA-162582\", \"supporting_discovery_ids\": [0, 3]}\n    ],\n    \"complexes\": [],\n    \"partners\": [\"LYN\", \"BTK\", \"HCLS1\", \"TXK\", \"PRKCD\"],\n    \"other_free_text\": []\n  }\n}\n```"}