{"gene":"IRAK4","run_date":"2026-06-10T01:55:23","timeline":{"discoveries":[{"year":2010,"finding":"Crystal structure of the MyD88-IRAK4-IRAK2 death domain complex reveals a left-handed helical oligomer (Myddosome) comprising 6 MyD88, 4 IRAK4, and 4 IRAK2 death domains. Assembly is hierarchical: MyD88 recruits IRAK4 first, then the MyD88-IRAK4 subcomplex recruits IRAK4 substrates IRAK2 or IRAK1. Composite binding sites mediated by molecular complementarity and surface electrostatics govern specificity. Proximity of recruited IRAK kinase domains enables phosphorylation and activation.","method":"X-ray crystallography of ternary death-domain complex; mutagenesis of composite binding sites; functional validation of signaling mutations","journal":"Nature","confidence":"High","confidence_rationale":"Tier 1 / Strong — atomic-resolution crystal structure combined with mutagenesis and functional validation in a single rigorous study","pmids":["20485341"],"is_preprint":false},{"year":2002,"finding":"IRAK-4 is indispensable for IL-1R and TLR signaling in vivo; gene-targeted IRAK-4-deficient mice are completely resistant to lethal LPS doses and severely impaired in responses to viral and bacterial challenges, establishing IRAK-4 as an essential kinase in innate immunity.","method":"Gene targeting (knockout mice); in vivo LPS challenge; cytokine measurements in cultured cells","journal":"Nature","confidence":"High","confidence_rationale":"Tier 2 / Strong — clean knockout with multiple defined phenotypic readouts, replicated across multiple TLR and IL-1R contexts","pmids":["11923871"],"is_preprint":false},{"year":2014,"finding":"Unphosphorylated IRAK4 dimerizes in solution (KD ~2.5 µM) via its kinase domain. Myddosome assembly greatly enhances IRAK4 kinase domain autophosphorylation at sub-KD concentrations. Crystal structure of the unphosphorylated IRAK4 kinase domain dimer captures a trans-autophosphorylation conformation where the activation loop phosphosite of one monomer is positioned for phosphotransfer by its partner. Dimerization is required for IRAK4 autophosphorylation in vitro and for ligand-dependent signaling in cells.","method":"Biophysical dimerization assays; X-ray crystallography of unphosphorylated kinase domain dimer; in vitro autophosphorylation assays; cell-based signaling assays with dimerization mutants","journal":"Molecular cell","confidence":"High","confidence_rationale":"Tier 1 / Strong — reconstitution in vitro, crystal structure, and mutagenesis with cellular validation in one study","pmids":["25201411"],"is_preprint":false},{"year":2004,"finding":"IRAK-4 is recruited to the IL-1R complex upon IL-1 stimulation and is required for the subsequent recruitment and activation/degradation of IRAK-1. Reconstitution of IRAK-4-deficient cells with wild-type vs. kinase-inactive IRAK-4 shows that kinase activity is required for optimal activation of IRAK-1, NF-κB, and JNK and maximal induction of inflammatory cytokines, but kinase-inactive IRAK-4 can still mediate some signals (scaffold function).","method":"Co-immunoprecipitation; reconstitution of IRAK-4-deficient cells with WT or kinase-inactive IRAK-4; NF-κB/JNK activation assays; cytokine induction assays","journal":"The Journal of biological chemistry","confidence":"High","confidence_rationale":"Tier 2 / Strong — reciprocal reconstitution experiments with multiple orthogonal readouts; replicated in subsequent studies","pmids":["15292196"],"is_preprint":false},{"year":2007,"finding":"IRAK4 kinase activity is critical for TLR-mediated innate immune responses: IRAK4 kinase-inactive knock-in mice are completely resistant to LPS- and CpG-induced shock. Kinase inactivity impairs TLR-mediated cytokine/chemokine induction in part by reducing LPS/R848/IL-1-mediated mRNA stability. TLR7- and TLR9-mediated type I interferon production in plasmacytoid dendritic cells is abolished in the absence of IRAK4 kinase activity.","method":"IRAK4 kinase-inactive knock-in mouse; in vivo LPS/CpG shock model; bone marrow-derived macrophage cytokine assays; pDC type I IFN measurement; mRNA stability assays","journal":"The Journal of experimental medicine","confidence":"High","confidence_rationale":"Tier 2 / Strong — knock-in mice with multiple orthogonal readouts across cell types and stimuli","pmids":["17470642"],"is_preprint":false},{"year":2018,"finding":"IRAK4's scaffolding function (interaction with MyD88) is more critical for IL-1 signaling than its kinase activity. Kinase-inactive IRAK4 has stronger association with MyD88 and weaker association with IRAK1. Loss of MyD88 interaction (R12C compound variant) impairs IL-1-induced signaling more than loss of kinase activity (D329A variant). IRAK4 kinase activity modulates signal strength by controlling association of IRAK4, MyD88, and IRAK1.","method":"Co-immunoprecipitation of IRAK4 variants with MyD88/IRAK1; reconstitution of IRAK4-deficient cells; cytokine and NF-κB signaling quantitation; IRAK4 patient variant characterization","journal":"The Journal of biological chemistry","confidence":"High","confidence_rationale":"Tier 2 / Moderate — multiple orthogonal methods (Co-IP, reconstitution, cytokine assays), single lab, rigorous variant dissection","pmids":["30115681"],"is_preprint":false},{"year":2022,"finding":"The IRAK4 scaffold (not just its kinase activity) is required for activation of TRAF6 by both MyD88 and TRIF pathways downstream of TLR4. IRAK4 therefore integrates both MYD88-dependent and TRIF-dependent TLR4 signaling, an unexpected scaffold role beyond the MyD88 pathway.","method":"Genetic epistasis using IRAK4-deficient cells; kinase inhibitor dissecting kinase vs scaffold functions; measurement of TRAF6 activation and downstream signaling","journal":"Cell reports","confidence":"Medium","confidence_rationale":"Tier 2 / Weak — single lab, clean genetic and pharmacological dissection but limited orthogonal validation of the TRIF-IRAK4 scaffold claim","pmids":["35977521"],"is_preprint":false},{"year":2018,"finding":"IRAK4 has a critical scaffold function in Myddosome formation that is independent of its kinase activity; selective IRAK4 kinase inhibition stabilizes Myddosome complexes while ablating TLR cytokine responses. IRAK4 kinase activity is dispensable for NF-κB and MAPK activation but essential for MyD88-dependent inflammatory cytokine production.","method":"Isolation of Myddosome complexes from primary mouse macrophages by co-immunoprecipitation; selective IRAK4 kinase inhibitor; kinetics of myddosome assembly/disassembly; cytokine and NF-κB/MAPK signaling assays","journal":"The Journal of biological chemistry","confidence":"High","confidence_rationale":"Tier 2 / Moderate — reciprocal Co-IP from primary cells with pharmacological dissection, multiple orthogonal readouts, single lab","pmids":["30076215"],"is_preprint":false},{"year":2004,"finding":"IRAK4 kinase activity is redundant with IRAK1 kinase activity for IL-1-induced NF-κB, JNK activation, and IRAK phosphorylation in human IRAK4-deficient cells; kinase-inactive IRAK4 fully restores IL-1 signaling in these cells. Only combined inactivation of both IRAK and IRAK4 kinase activities efficiently abolishes the IL-1 pathway. IRAK4 is required for efficient recruitment of IRAK1 to the IL-1 receptor complex.","method":"Reconstitution of human IRAK4-deficient cells with WT or kinase-inactive IRAK4; NF-κB reporter assay; JNK activation; co-immunoprecipitation of IRAK1 with IL-1R complex","journal":"The Journal of biological chemistry","confidence":"High","confidence_rationale":"Tier 2 / Moderate — human patient-derived IRAK4-deficient cells reconstituted with multiple constructs; orthogonal signaling readouts","pmids":["15084582"],"is_preprint":false},{"year":2002,"finding":"Pellino 1 interacts with IRAK4, IRAK1, and TRAF6 in a signal-dependent complex required for NF-κB activation and IL-8 gene expression in response to IL-1. The Pellino 1-IRAK-IRAK4-TRAF6 complex is located between the IL-1 receptor complex and the TAK1 complex in the IL-1 pathway.","method":"Co-immunoprecipitation; NF-κB reporter assay; IL-8 gene expression measurement; dominant-negative/overexpression analysis","journal":"The Journal of biological chemistry","confidence":"Medium","confidence_rationale":"Tier 3 / Moderate — single lab, Co-IP plus functional readouts, but no direct reconstitution or structural validation","pmids":["12496252"],"is_preprint":false},{"year":2003,"finding":"Pellino2 is an interaction partner and substrate of IRAK4 (and IRAK1); Pellino2 interacts with both kinase-active and kinase-inactive forms of IRAK4 and IRAK1. Pellino2 acts as a scaffolding protein in TIR signaling but does not activate a specific transcription factor.","method":"Yeast two-hybrid; Co-immunoprecipitation; in vitro kinase assay showing Pellino2 phosphorylation by IRAK4; RNAi knockdown functional studies","journal":"FEBS letters","confidence":"Medium","confidence_rationale":"Tier 1 / Weak — in vitro kinase assay establishing substrate relationship, but single lab and limited mechanistic follow-up","pmids":["12860405"],"is_preprint":false},{"year":2010,"finding":"IRAK1 and IRAK4 directly phosphorylate Mal (MyD88 adaptor-like/TIRAP), promoting its ubiquitination and proteasomal degradation. Kinase-inactive forms of either IRAK do not cause Mal depletion. LPS-induced Mal degradation is blocked by IRAK1/4 inhibitor or IRAK1/IRAK4 knockdown. MyD88 is not a substrate for either IRAK. This phosphorylation-driven Mal degradation negatively regulates TLR2 and TLR4 signaling.","method":"In vitro kinase assay (direct phosphorylation of Mal by IRAK1/IRAK4); co-expression with kinase-inactive mutants; ubiquitination assay; LPS stimulation with IRAK1/4 inhibitor and siRNA knockdown","journal":"The Journal of biological chemistry","confidence":"High","confidence_rationale":"Tier 1 / Moderate — in vitro kinase assay with mutagenesis controls, plus siRNA/pharmacological confirmation, single lab but multiple orthogonal methods","pmids":["20400509"],"is_preprint":false},{"year":2007,"finding":"IRAK-4 phosphorylates p47phox (NADPH oxidase cytosolic factor) at serine and threonine residues (Thr133, Ser288, Thr356 identified by tandem MS), distinct from PKC phosphorylation sites. IRAK-4-phosphorylated p47phox activates the NADPH oxidase in a cell-free system. Endogenous IRAK-4 co-immunoprecipitates with p47phox and co-localizes at the plasma membrane after LPS stimulation. IRAK-4 overexpression increases NADPH oxidase activity in response to LPS.","method":"In vitro kinase assay; tandem mass spectrometry; cell-free NADPH oxidase activation assay; co-immunoprecipitation; immunofluorescence co-localization; IRAK-4 overexpression","journal":"The Biochemical journal","confidence":"High","confidence_rationale":"Tier 1 / Moderate — in vitro kinase assay with MS site identification, cell-free reconstitution, and Co-IP/imaging, single lab but multiple orthogonal methods","pmids":["17217339"],"is_preprint":false},{"year":2017,"finding":"IRAK4 is constitutively active as a kinase in resting cells; its intrinsic catalytic activity toward Pellino1 is not significantly increased by IL-1 stimulation. The IL-1-stimulated trans-autophosphorylation of IRAK4 is initiated by MyD88-induced dimerization rather than by an increase in intrinsic catalytic activity. In contrast, IRAK1 is inactive in unstimulated cells and activated by IL-1 or Pam3CSK4 through an allosteric mechanism dependent on its interaction with IRAK4, not by IRAK4-mediated phosphorylation.","method":"Pellino1 substrate-based kinase activity assays in human cell extracts; selective IRAK1 and IRAK4 pharmacological inhibitors; dephosphorylation/deubiquitylation experiments; IL-1R-expressing HEK293 cells, THP1 monocytes, primary macrophages","journal":"The Biochemical journal","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — novel cell-extract kinase assays with selective inhibitors across multiple cell types, single lab","pmids":["28512203"],"is_preprint":false},{"year":2017,"finding":"IRAK4 kinase activity controls TLR7/8-stimulated inflammatory cytokine production in human monocytes through activation of the transcription factor IRF5. IRAK4 inhibition abolishes IRF5 nuclear translocation and IRF5 binding to cytokine gene promoters. Mechanistically, IRAK4 kinase activity is required for IKKβ phosphorylation, which in turn activates IRF5; this pathway is distinct from canonical IKKβ-mediated IκB phosphorylation and NF-κB activation.","method":"Selective IRAK4 kinase inhibitor in primary human monocytes; transcriptomic analysis; biochemical IRF5 nuclear translocation assay; chromatin immunoprecipitation; IKKβ and TAK1 pharmacological inhibition","journal":"The Journal of biological chemistry","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — multiple orthogonal methods in primary human cells, single lab, no genetic validation of the IRF5 axis","pmids":["28924041"],"is_preprint":false},{"year":2019,"finding":"U2AF1 mutations cause retention of exon 4 in IRAK4 mRNA, producing a longer isoform (IRAK4-L) that assembles with the Myddosome more efficiently and results in maximal NF-κB activation, driving oncogenic signaling in MDS and AML. Inhibition of IRAK4-L abrogates leukemic cell growth.","method":"Global exon usage analysis in AML samples; functional expression of IRAK4-L vs short isoform; NF-κB activation assays; leukemic cell growth inhibition; U2AF1 mutant cell models","journal":"Nature cell biology","confidence":"High","confidence_rationale":"Tier 2 / Moderate — multiple orthogonal methods (splicing analysis, functional assays, growth inhibition) in patient-derived and cell-line models, single lab","pmids":["31011167"],"is_preprint":false},{"year":2019,"finding":"Crystal structures of unphosphorylated IRAK4 kinase domain in complex with ATP analog AMP-PNP (αC-out inactive conformation) and with type I inhibitors (DFG-in, αC-in active conformation) or type II inhibitors ponatinib/HG-12-6 (DFG-out conformation) reveal conformational flexibility of the unphosphorylated kinase. This flexibility allows unphosphorylated IRAK4 to adopt both active and inactive conformations depending on the bound ligand.","method":"X-ray crystallography of unphosphorylated IRAK4 kinase domain in multiple inhibitor-bound states (≤2.6 Å resolution); small-molecule screening for unphosphorylated IRAK4-selective inhibitors","journal":"The Journal of biological chemistry","confidence":"High","confidence_rationale":"Tier 1 / Moderate — multiple high-resolution crystal structures with different bound ligands, single lab","pmids":["30679311"],"is_preprint":false},{"year":2004,"finding":"Prolonged stimulation of TLR2, TLR4, or TLR9 (but not TLR3) causes proteasome-dependent down-regulation of IRAK-4 protein and appearance of a 32-kDa C-terminal fragment, without affecting IRAK-4 mRNA levels. This down-regulation requires NF-κB activation and new protein synthesis and is blocked by proteasome inhibitors.","method":"Western blot analysis of IRAK-4 protein levels in RAW 264 macrophages after TLR stimulation; proteasome inhibitors; NF-κB inhibition; RT-PCR for mRNA levels","journal":"Journal of leukocyte biology","confidence":"Medium","confidence_rationale":"Tier 3 / Moderate — pharmacological dissection with multiple inhibitors, single cell line, no direct identification of the responsible protease","pmids":["15258191"],"is_preprint":false},{"year":2011,"finding":"Induction of endotoxin tolerance in vivo blocks TLR4-driven IRAK4 phosphorylation and activation in macrophages, while increasing expression of negative regulators IRAK-M, SHIP-1, and A20. Impaired IRAK4 activation correlates with reduced IκBα degradation, p38 phosphorylation, and cytokine expression.","method":"In vivo LPS tolerization mouse model; IRAK4 phosphorylation assay in peritoneal and splenic macrophages; RT-PCR for negative regulators; cytokine mRNA and protein measurements","journal":"Journal of leukocyte biology","confidence":"Medium","confidence_rationale":"Tier 2 / Weak — clean in vivo model with defined molecular readouts for IRAK4 phosphorylation status, single lab","pmids":["21934070"],"is_preprint":false},{"year":2021,"finding":"SARS-CoV-2-induced activation of human plasmacytoid dendritic cells (pDCs) and production of type I IFN, IL-6, and other cytokines critically depends on IRAK4 and UNC93B1, as established using pDCs from patients with genetic deficiencies in these proteins.","method":"Primary pDCs from IRAK4- and UNC93B1-deficient patients stimulated with live SARS-CoV-2 isolates; cytokine measurement; pDC subset diversification analysis","journal":"The Journal of experimental medicine","confidence":"High","confidence_rationale":"Tier 2 / Strong — human genetic loss-of-function in primary cells with defined mechanistic readouts; replicated across multiple patients","pmids":["33533916"],"is_preprint":false},{"year":2016,"finding":"In pericytes, MyD88 and its downstream kinase IRAK4 intrinsically control pericyte migration and conversion to myofibroblasts (fibrogenic differentiation), independent of their roles in classical immune cells. Pericyte-specific MyD88 ablation or pharmacological IRAK4 inhibition in vivo protects against kidney fibrosis.","method":"Pericyte-specific MyD88 conditional knockout; pharmacological IRAK4 inhibitor in kidney injury models; pericyte migration and myofibroblast differentiation assays","journal":"The Journal of clinical investigation","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — cell-type-specific genetic deletion combined with pharmacological inhibition and in vivo fibrosis model, single lab","pmids":["27869651"],"is_preprint":false},{"year":2010,"finding":"Two human MyD88 death domain variants (S34Y and R98C) cause severely reduced NF-κB activation due to impaired MyD88 homo-oligomerization and reduced IRAK4 interaction. Structural modeling identifies Ser34 and Arg98 as residues important for Myddosome assembly. MyD88 homo-oligomerization and IRAK4 interaction are modulated by the MyD88 TIR domain and the IRAK4 kinase domain.","method":"Co-immunoprecipitation; NF-κB reporter assays; structural modeling of Myddosome assembly; receptor-specific signaling assays with MyD88 variants","journal":"The Journal of biological chemistry","confidence":"Medium","confidence_rationale":"Tier 3 / Moderate — Co-IP and functional assays with multiple receptor contexts, single lab, structural modeling not experimentally validated by crystallography","pmids":["20966070"],"is_preprint":false},{"year":2019,"finding":"Acetylation of IRAK4 at K34 and phosphorylation at T345/S346 are post-translational modifications induced by LPS/D-Gal stimulation in vivo; oridonin attenuates these modifications and protects against acute liver injury.","method":"Western blot with modification-specific antibodies; RNA-seq and KEGG pathway analysis; in vivo ALI mouse model","journal":"Mediators of inflammation","confidence":"Low","confidence_rationale":"Tier 3 / Weak — single lab, pharmacological intervention without direct identification of the acetyltransferase or phosphorylation writer for K34","pmids":["31611735"],"is_preprint":false},{"year":2009,"finding":"IRAK4 kinase activity is required for IL-1-mediated induction of IL-23R expression, STAT3 activation by IL-23, and Th17 differentiation. Adoptive transfer of IRAK4 kinase-inactive Th17 cells fails to induce EAE, demonstrating a T-cell-intrinsic requirement for IRAK4 kinase activity in Th17-mediated autoimmunity.","method":"IRAK4 kinase-inactive knock-in mice; EAE model; adoptive transfer of Th17 cells; flow cytometry; cytokine assays; IL-23R expression analysis","journal":"Journal of immunology","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — knock-in mice with adoptive transfer experiments and multiple readouts, single lab","pmids":["19542468"],"is_preprint":false},{"year":2021,"finding":"IRAK4 phosphorylates IRF5 and IRF4 in microglia (confirmed by Co-IP showing IRAK4 forms a Myddosome with MyD88/IRF5/IRF4); IRAK4 inhibition blocks IRF5/IRF4 nuclear translocation and quenches pro-inflammatory microglial responses to ischemia, improving neuronal viability.","method":"Co-immunoprecipitation of IRAK4/MyD88/IRF5/IRF4 complex; IRAK4 inhibitor (ND2158); nuclear translocation assay by immunofluorescence; ELISA for cytokines; oxygen-glucose deprivation model","journal":"Cells","confidence":"Medium","confidence_rationale":"Tier 3 / Moderate — Co-IP of complex plus functional inhibitor experiments, but direct phosphorylation of IRFs by IRAK4 not demonstrated in vitro in this study","pmids":["33573200"],"is_preprint":false}],"current_model":"IRAK4 is a serine/threonine kinase that functions as the master upstream kinase in the TLR/IL-1R signaling cascade: upon receptor activation, IRAK4 is recruited to the membrane-proximal Myddosome — a left-handed helical oligomer of MyD88, IRAK4, and IRAK2/IRAK1 death domains — where Myddosome assembly drives IRAK4 kinase domain dimerization and trans-autophosphorylation, activating IRAK4 and enabling it to phosphorylate downstream substrates (including IRAK1, Mal/TIRAP, Pellino1/2, p47phox, and IRF5), ultimately leading to NF-κB, MAPK, and IRF5 activation and inflammatory cytokine production; IRAK4 also exerts a kinase-independent scaffold function essential for Myddosome stability and TRAF6 activation, and its activity is regulated by prolonged TLR stimulation via proteasomal degradation and by miRNA-mediated downregulation."},"narrative":{"mechanistic_narrative":"IRAK4 is the apical serine/threonine kinase of the Toll-like receptor (TLR) and IL-1 receptor (IL-1R) innate immune signaling cascade, indispensable in vivo for responses to LPS and microbial challenge [PMID:11923871]. Upon receptor engagement, IRAK4 is recruited to the membrane-proximal Myddosome, a left-handed helical death-domain oligomer of 6 MyD88, 4 IRAK4, and 4 IRAK2/IRAK1 subunits assembled hierarchically as MyD88 first recruits IRAK4, which then recruits its IRAK substrates [PMID:20485341]. Myddosome-driven dimerization of the IRAK4 kinase domain enables trans-autophosphorylation across the activation loop and is required for ligand-dependent signaling; activation reflects MyD88-induced dimerization rather than a change in intrinsic catalytic activity, since IRAK4 is constitutively active toward Pellino1 in resting cells [PMID:25201411, PMID:28512203]. Active IRAK4 phosphorylates and recruits IRAK1, and its substrate repertoire includes Pellino2, the adaptor Mal/TIRAP (driving its ubiquitination and proteasomal degradation as a negative feedback on TLR2/4), and the NADPH oxidase factor p47phox [PMID:15292196, PMID:12860405, PMID:20400509, PMID:17217339]. Downstream, IRAK4 nucleates a Pellino1–IRAK–TRAF6 complex bridging the receptor and TAK1, and its kinase activity drives IKKβ-dependent IRF5 activation for inflammatory cytokine transcription [PMID:12496252, PMID:28924041]. IRAK4 additionally performs a kinase-independent scaffold function: kinase-inactive IRAK4 retains association with MyD88 and supports NF-κB/MAPK activation and TRAF6 activation from both MyD88- and TRIF-dependent TLR4 arms, while kinase activity primarily tunes signal strength and inflammatory cytokine output [PMID:30115681, PMID:35977521, PMID:30076215, PMID:15084582]. IRAK4 activity is downregulated by prolonged TLR stimulation via proteasomal degradation and by induction of negative regulators during endotoxin tolerance [PMID:15258191, PMID:21934070]. A U2AF1-mutant splice isoform (IRAK4-L) assembles more efficiently with the Myddosome to drive oncogenic NF-κB signaling in MDS/AML [PMID:31011167].","teleology":[{"year":2002,"claim":"Established IRAK4 as a non-redundant, essential kinase in innate immunity rather than one of several interchangeable signaling components.","evidence":"Gene-targeted IRAK4-knockout mice challenged with LPS and microbial pathogens","pmids":["11923871"],"confidence":"High","gaps":["Did not resolve whether catalytic activity or scaffolding accounts for the phenotype","No molecular structure of how IRAK4 engages the receptor complex"]},{"year":2002,"claim":"Placed IRAK4 within a defined signal-dependent complex, identifying Pellino1 as a partner bridging the receptor to the TAK1 module.","evidence":"Co-IP and NF-κB/IL-8 reporter assays of a Pellino1–IRAK1–IRAK4–TRAF6 complex","pmids":["12496252"],"confidence":"Medium","gaps":["No reconstitution or structural validation of complex stoichiometry","Direct substrate relationship not established here"]},{"year":2003,"claim":"Identified Pellino2 as a direct IRAK4 substrate, extending IRAK4's catalytic repertoire beyond the IRAK kinases.","evidence":"Yeast two-hybrid, Co-IP, and in vitro kinase assay showing Pellino2 phosphorylation","pmids":["12860405"],"confidence":"Medium","gaps":["Phosphosites not mapped","Functional consequence of Pellino2 phosphorylation not defined"]},{"year":2004,"claim":"Dissected kinase versus scaffold contributions, showing IRAK4 is required to recruit and activate IRAK1 but that kinase-inactive IRAK4 still supports partial signaling.","evidence":"Reciprocal reconstitution of IRAK4-deficient cells with WT vs kinase-inactive IRAK4; NF-κB/JNK and cytokine readouts","pmids":["15292196","15084582"],"confidence":"High","gaps":["Did not establish in vivo physiological weight of kinase vs scaffold roles","Redundancy with IRAK1 kinase activity left the catalytic requirement ambiguous"]},{"year":2004,"claim":"Revealed that IRAK4 protein levels are actively controlled, linking prolonged TLR signaling to proteasomal turnover of the kinase.","evidence":"Western blot of IRAK4 levels in macrophages after sustained TLR stimulation with proteasome and NF-κB inhibitors","pmids":["15258191"],"confidence":"Medium","gaps":["Responsible protease/E3 ligase not identified","Single cell line; in vivo relevance not tested"]},{"year":2007,"claim":"Demonstrated in vivo that IRAK4 catalytic activity is required for TLR-driven inflammation and type I IFN, settling that the kinase function is physiologically essential.","evidence":"IRAK4 kinase-inactive knock-in mice in LPS/CpG shock; pDC IFN and mRNA-stability assays","pmids":["17470642"],"confidence":"High","gaps":["Did not define the direct substrates mediating cytokine mRNA stability","Mechanism of IRF/IFN induction not mapped"]},{"year":2007,"claim":"Connected IRAK4 to the NADPH oxidase by identifying p47phox as a direct, site-specific substrate, broadening IRAK4 output beyond transcription factors.","evidence":"In vitro kinase assay with MS phosphosite mapping, cell-free oxidase reconstitution, Co-IP and membrane co-localization","pmids":["17217339"],"confidence":"High","gaps":["In vivo contribution of IRAK4-p47phox phosphorylation to oxidative burst not quantified"]},{"year":2009,"claim":"Extended IRAK4 kinase function to adaptive immunity, showing a T-cell-intrinsic requirement for Th17 differentiation and autoimmunity.","evidence":"Kinase-inactive knock-in mice, Th17 adoptive transfer, and EAE model","pmids":["19542468"],"confidence":"Medium","gaps":["Direct IRAK4 substrate in T cells not identified","Single autoimmune model"]},{"year":2010,"claim":"Provided the structural basis for IRAK4 recruitment by resolving the Myddosome as a defined helical death-domain oligomer with hierarchical assembly.","evidence":"X-ray crystallography of the MyD88–IRAK4–IRAK2 death-domain complex with composite-site mutagenesis","pmids":["20485341"],"confidence":"High","gaps":["Did not resolve how kinase domains are activated within the assembled complex","Dynamics of assembly/disassembly not captured"]},{"year":2010,"claim":"Established a negative-feedback role for IRAK4 catalysis by showing it phosphorylates Mal/TIRAP to trigger its degradation, while excluding MyD88 as a substrate.","evidence":"In vitro kinase, ubiquitination, and LPS-stimulation assays with kinase-inactive mutants and inhibitor/siRNA","pmids":["20400509"],"confidence":"High","gaps":["E3 ligase mediating Mal ubiquitination not identified here","Quantitative impact on signal duration not measured"]},{"year":2014,"claim":"Defined the activation mechanism, showing Myddosome-driven kinase-domain dimerization positions activation loops for trans-autophosphorylation.","evidence":"Biophysical dimerization assays, crystal structure of the unphosphorylated kinase domain dimer, and signaling assays with dimerization mutants","pmids":["25201411"],"confidence":"High","gaps":["Did not address whether intrinsic catalytic activity changes upon activation","Substrate selection in the dimer not defined"]},{"year":2017,"claim":"Reframed IRAK4 activation as proximity-driven rather than catalysis-switched, showing IRAK4 is constitutively active and activates IRAK1 allosterically.","evidence":"Pellino1 substrate-based kinase assays in cell extracts with selective IRAK1/IRAK4 inhibitors across multiple cell types","pmids":["28512203"],"confidence":"Medium","gaps":["Cell-extract assay; physiological substrate kinetics not measured","Single lab"]},{"year":2017,"claim":"Identified an IKKβ–IRF5 axis downstream of IRAK4 kinase activity, distinct from canonical NF-κB activation, for TLR7/8 cytokine output.","evidence":"Selective IRAK4 inhibitor in primary human monocytes with IRF5 translocation, ChIP, and IKKβ/TAK1 inhibitor studies","pmids":["28924041"],"confidence":"Medium","gaps":["No genetic validation of the IRF5 axis","Direct IRAK4 substrate upstream of IKKβ not defined"]},{"year":2018,"claim":"Established that the IRAK4 scaffold function dominates IL-1 signaling and that kinase activity primarily tunes complex assembly and signal strength.","evidence":"Co-IP of IRAK4 variants with MyD88/IRAK1 and reconstitution/cytokine assays using kinase-dead and MyD88-binding-deficient variants","pmids":["30115681","30076215"],"confidence":"High","gaps":["Quantitative contribution of scaffold vs kinase across receptors not fully resolved","Single lab for each dissection"]},{"year":2019,"claim":"Linked IRAK4 to malignancy via a U2AF1-driven splice isoform (IRAK4-L) that hyperassembles with the Myddosome to drive oncogenic NF-κB signaling.","evidence":"Exon-usage analysis, functional isoform expression, NF-κB and leukemic growth assays in patient-derived and mutant models","pmids":["31011167"],"confidence":"High","gaps":["Structural basis of enhanced IRAK4-L Myddosome incorporation not resolved","Therapeutic dependence beyond cell models not established"]},{"year":2019,"claim":"Characterized the conformational plasticity of unphosphorylated IRAK4, informing type I vs type II inhibitor design.","evidence":"Multiple crystal structures of the unphosphorylated kinase domain bound to AMP-PNP and inhibitors","pmids":["30679311"],"confidence":"High","gaps":["Functional consequence of conformational states in cells not measured"]},{"year":2022,"claim":"Extended the IRAK4 scaffold requirement to the TRIF arm of TLR4, positioning IRAK4 as an integrator of MyD88- and TRIF-dependent TRAF6 activation.","evidence":"Genetic epistasis in IRAK4-deficient cells plus kinase-inhibitor dissection of TRAF6 activation","pmids":["35977521"],"confidence":"Medium","gaps":["Mechanism of IRAK4 engagement with the TRIF pathway not defined","Single lab; limited orthogonal validation"]},{"year":null,"claim":"How the IRAK4 kinase domain selects among its diverse substrates (IRAK1, Pellino1/2, Mal, p47phox, IRF5) within the Myddosome, and how acetylation and other post-translational modifications regulate IRAK4 in vivo, remain unresolved.","evidence":"","pmids":[],"confidence":"Low","gaps":["Writers/erasers of IRAK4 K34 acetylation and T345/S346 phosphorylation not identified","Direct in vitro phosphorylation of IRF5/IRF4 by IRAK4 not demonstrated","Rules governing substrate selection in the activated dimer unknown"]}],"mechanism_profile":{"molecular_activity":[{"term_id":"GO:0140096","term_label":"catalytic activity, acting on a protein","supporting_discovery_ids":[3,10,11,12]},{"term_id":"GO:0016740","term_label":"transferase activity","supporting_discovery_ids":[2,11,12]},{"term_id":"GO:0140657","term_label":"ATP-dependent activity","supporting_discovery_ids":[2,16]},{"term_id":"GO:0060089","term_label":"molecular transducer activity","supporting_discovery_ids":[0,1]},{"term_id":"GO:0060090","term_label":"molecular adaptor activity","supporting_discovery_ids":[5,6,7]}],"localization":[{"term_id":"GO:0005886","term_label":"plasma membrane","supporting_discovery_ids":[12]},{"term_id":"GO:0005829","term_label":"cytosol","supporting_discovery_ids":[2,13]}],"pathway":[{"term_id":"R-HSA-168256","term_label":"Immune System","supporting_discovery_ids":[1,4,19]},{"term_id":"R-HSA-162582","term_label":"Signal Transduction","supporting_discovery_ids":[0,3,9]},{"term_id":"R-HSA-1643685","term_label":"Disease","supporting_discovery_ids":[15,20]}],"complexes":["Myddosome (MyD88-IRAK4-IRAK2/IRAK1)","Pellino1-IRAK-IRAK4-TRAF6 complex"],"partners":["MYD88","IRAK1","IRAK2","TRAF6","PELLINO1","PELLINO2","TIRAP","IRF5"],"other_free_text":[]}},"prefetch_data":{"uniprot":{"accession":"Q9NWZ3","full_name":"Interleukin-1 receptor-associated kinase 4","aliases":["Renal carcinoma antigen NY-REN-64"],"length_aa":460,"mass_kda":51.5,"function":"Serine/threonine-protein kinase that plays a critical role in initiating innate immune response against foreign pathogens. 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cancer research : an official journal of the American Association for Cancer Research","url":"https://pubmed.ncbi.nlm.nih.gov/36749885","citation_count":20,"is_preprint":false},{"pmid":"39807338","id":"PMC_39807338","title":"Emerging interleukin-1 receptor-associated kinase 4 (IRAK4) inhibitors or degraders as therapeutic agents for autoimmune diseases and cancer.","date":"2024","source":"Acta pharmaceutica Sinica. 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immunology","url":"https://pubmed.ncbi.nlm.nih.gov/24398261","citation_count":19,"is_preprint":false},{"pmid":"36076574","id":"PMC_36076574","title":"Oral IRAK4 inhibitor BAY-1834845 prevents acute respiratory distress syndrome.","date":"2022","source":"Biomedicine & pharmacotherapy = Biomedecine & pharmacotherapie","url":"https://pubmed.ncbi.nlm.nih.gov/36076574","citation_count":18,"is_preprint":false},{"pmid":"31846774","id":"PMC_31846774","title":"Molecular characterization, expression and functional analysis of IRAK1 and IRAK4 in Nile tilapia (Oreochromis niloticus).","date":"2019","source":"Fish & shellfish immunology","url":"https://pubmed.ncbi.nlm.nih.gov/31846774","citation_count":18,"is_preprint":false},{"pmid":"28408332","id":"PMC_28408332","title":"Molecular cloning, structural modeling, and expression analysis of MyD88 and IRAK4 of golden pompano (Trachinotus ovatus).","date":"2017","source":"Developmental and comparative 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letters","url":"https://pubmed.ncbi.nlm.nih.gov/28501511","citation_count":15,"is_preprint":false}],"cost":{"stage1":{"model":"claude-sonnet-4-6","input_tokens":50497,"output_tokens":7071,"usd":0.128778,"stage1_stop_reason":"end_turn"},"stage2":{"model":"claude-opus-4-8","input_tokens":16182,"output_tokens":5276,"usd":0.106405,"stage2_stop_reason":"end_turn"},"total_usd":0.235183,"stage1_batch_id":"msgbatch_01DUPACZi7AAWwuZiUjseQF4","stage2_batch_id":"msgbatch_018yt7chE3f48PEFtDwtj6AE","note":"batch pricing = 50% of standard"},"stage1_raw":"```json\n{\n  \"discoveries\": [\n    {\n      \"year\": 2010,\n      \"finding\": \"Crystal structure of the MyD88-IRAK4-IRAK2 death domain complex reveals a left-handed helical oligomer (Myddosome) comprising 6 MyD88, 4 IRAK4, and 4 IRAK2 death domains. Assembly is hierarchical: MyD88 recruits IRAK4 first, then the MyD88-IRAK4 subcomplex recruits IRAK4 substrates IRAK2 or IRAK1. Composite binding sites mediated by molecular complementarity and surface electrostatics govern specificity. Proximity of recruited IRAK kinase domains enables phosphorylation and activation.\",\n      \"method\": \"X-ray crystallography of ternary death-domain complex; mutagenesis of composite binding sites; functional validation of signaling mutations\",\n      \"journal\": \"Nature\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1 / Strong — atomic-resolution crystal structure combined with mutagenesis and functional validation in a single rigorous study\",\n      \"pmids\": [\"20485341\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2002,\n      \"finding\": \"IRAK-4 is indispensable for IL-1R and TLR signaling in vivo; gene-targeted IRAK-4-deficient mice are completely resistant to lethal LPS doses and severely impaired in responses to viral and bacterial challenges, establishing IRAK-4 as an essential kinase in innate immunity.\",\n      \"method\": \"Gene targeting (knockout mice); in vivo LPS challenge; cytokine measurements in cultured cells\",\n      \"journal\": \"Nature\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — clean knockout with multiple defined phenotypic readouts, replicated across multiple TLR and IL-1R contexts\",\n      \"pmids\": [\"11923871\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2014,\n      \"finding\": \"Unphosphorylated IRAK4 dimerizes in solution (KD ~2.5 µM) via its kinase domain. Myddosome assembly greatly enhances IRAK4 kinase domain autophosphorylation at sub-KD concentrations. Crystal structure of the unphosphorylated IRAK4 kinase domain dimer captures a trans-autophosphorylation conformation where the activation loop phosphosite of one monomer is positioned for phosphotransfer by its partner. Dimerization is required for IRAK4 autophosphorylation in vitro and for ligand-dependent signaling in cells.\",\n      \"method\": \"Biophysical dimerization assays; X-ray crystallography of unphosphorylated kinase domain dimer; in vitro autophosphorylation assays; cell-based signaling assays with dimerization mutants\",\n      \"journal\": \"Molecular cell\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1 / Strong — reconstitution in vitro, crystal structure, and mutagenesis with cellular validation in one study\",\n      \"pmids\": [\"25201411\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2004,\n      \"finding\": \"IRAK-4 is recruited to the IL-1R complex upon IL-1 stimulation and is required for the subsequent recruitment and activation/degradation of IRAK-1. Reconstitution of IRAK-4-deficient cells with wild-type vs. kinase-inactive IRAK-4 shows that kinase activity is required for optimal activation of IRAK-1, NF-κB, and JNK and maximal induction of inflammatory cytokines, but kinase-inactive IRAK-4 can still mediate some signals (scaffold function).\",\n      \"method\": \"Co-immunoprecipitation; reconstitution of IRAK-4-deficient cells with WT or kinase-inactive IRAK-4; NF-κB/JNK activation assays; cytokine induction assays\",\n      \"journal\": \"The Journal of biological chemistry\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — reciprocal reconstitution experiments with multiple orthogonal readouts; replicated in subsequent studies\",\n      \"pmids\": [\"15292196\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2007,\n      \"finding\": \"IRAK4 kinase activity is critical for TLR-mediated innate immune responses: IRAK4 kinase-inactive knock-in mice are completely resistant to LPS- and CpG-induced shock. Kinase inactivity impairs TLR-mediated cytokine/chemokine induction in part by reducing LPS/R848/IL-1-mediated mRNA stability. TLR7- and TLR9-mediated type I interferon production in plasmacytoid dendritic cells is abolished in the absence of IRAK4 kinase activity.\",\n      \"method\": \"IRAK4 kinase-inactive knock-in mouse; in vivo LPS/CpG shock model; bone marrow-derived macrophage cytokine assays; pDC type I IFN measurement; mRNA stability assays\",\n      \"journal\": \"The Journal of experimental medicine\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — knock-in mice with multiple orthogonal readouts across cell types and stimuli\",\n      \"pmids\": [\"17470642\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2018,\n      \"finding\": \"IRAK4's scaffolding function (interaction with MyD88) is more critical for IL-1 signaling than its kinase activity. Kinase-inactive IRAK4 has stronger association with MyD88 and weaker association with IRAK1. Loss of MyD88 interaction (R12C compound variant) impairs IL-1-induced signaling more than loss of kinase activity (D329A variant). IRAK4 kinase activity modulates signal strength by controlling association of IRAK4, MyD88, and IRAK1.\",\n      \"method\": \"Co-immunoprecipitation of IRAK4 variants with MyD88/IRAK1; reconstitution of IRAK4-deficient cells; cytokine and NF-κB signaling quantitation; IRAK4 patient variant characterization\",\n      \"journal\": \"The Journal of biological chemistry\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — multiple orthogonal methods (Co-IP, reconstitution, cytokine assays), single lab, rigorous variant dissection\",\n      \"pmids\": [\"30115681\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2022,\n      \"finding\": \"The IRAK4 scaffold (not just its kinase activity) is required for activation of TRAF6 by both MyD88 and TRIF pathways downstream of TLR4. IRAK4 therefore integrates both MYD88-dependent and TRIF-dependent TLR4 signaling, an unexpected scaffold role beyond the MyD88 pathway.\",\n      \"method\": \"Genetic epistasis using IRAK4-deficient cells; kinase inhibitor dissecting kinase vs scaffold functions; measurement of TRAF6 activation and downstream signaling\",\n      \"journal\": \"Cell reports\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Weak — single lab, clean genetic and pharmacological dissection but limited orthogonal validation of the TRIF-IRAK4 scaffold claim\",\n      \"pmids\": [\"35977521\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2018,\n      \"finding\": \"IRAK4 has a critical scaffold function in Myddosome formation that is independent of its kinase activity; selective IRAK4 kinase inhibition stabilizes Myddosome complexes while ablating TLR cytokine responses. IRAK4 kinase activity is dispensable for NF-κB and MAPK activation but essential for MyD88-dependent inflammatory cytokine production.\",\n      \"method\": \"Isolation of Myddosome complexes from primary mouse macrophages by co-immunoprecipitation; selective IRAK4 kinase inhibitor; kinetics of myddosome assembly/disassembly; cytokine and NF-κB/MAPK signaling assays\",\n      \"journal\": \"The Journal of biological chemistry\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — reciprocal Co-IP from primary cells with pharmacological dissection, multiple orthogonal readouts, single lab\",\n      \"pmids\": [\"30076215\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2004,\n      \"finding\": \"IRAK4 kinase activity is redundant with IRAK1 kinase activity for IL-1-induced NF-κB, JNK activation, and IRAK phosphorylation in human IRAK4-deficient cells; kinase-inactive IRAK4 fully restores IL-1 signaling in these cells. Only combined inactivation of both IRAK and IRAK4 kinase activities efficiently abolishes the IL-1 pathway. IRAK4 is required for efficient recruitment of IRAK1 to the IL-1 receptor complex.\",\n      \"method\": \"Reconstitution of human IRAK4-deficient cells with WT or kinase-inactive IRAK4; NF-κB reporter assay; JNK activation; co-immunoprecipitation of IRAK1 with IL-1R complex\",\n      \"journal\": \"The Journal of biological chemistry\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — human patient-derived IRAK4-deficient cells reconstituted with multiple constructs; orthogonal signaling readouts\",\n      \"pmids\": [\"15084582\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2002,\n      \"finding\": \"Pellino 1 interacts with IRAK4, IRAK1, and TRAF6 in a signal-dependent complex required for NF-κB activation and IL-8 gene expression in response to IL-1. The Pellino 1-IRAK-IRAK4-TRAF6 complex is located between the IL-1 receptor complex and the TAK1 complex in the IL-1 pathway.\",\n      \"method\": \"Co-immunoprecipitation; NF-κB reporter assay; IL-8 gene expression measurement; dominant-negative/overexpression analysis\",\n      \"journal\": \"The Journal of biological chemistry\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 3 / Moderate — single lab, Co-IP plus functional readouts, but no direct reconstitution or structural validation\",\n      \"pmids\": [\"12496252\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2003,\n      \"finding\": \"Pellino2 is an interaction partner and substrate of IRAK4 (and IRAK1); Pellino2 interacts with both kinase-active and kinase-inactive forms of IRAK4 and IRAK1. Pellino2 acts as a scaffolding protein in TIR signaling but does not activate a specific transcription factor.\",\n      \"method\": \"Yeast two-hybrid; Co-immunoprecipitation; in vitro kinase assay showing Pellino2 phosphorylation by IRAK4; RNAi knockdown functional studies\",\n      \"journal\": \"FEBS letters\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 1 / Weak — in vitro kinase assay establishing substrate relationship, but single lab and limited mechanistic follow-up\",\n      \"pmids\": [\"12860405\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2010,\n      \"finding\": \"IRAK1 and IRAK4 directly phosphorylate Mal (MyD88 adaptor-like/TIRAP), promoting its ubiquitination and proteasomal degradation. Kinase-inactive forms of either IRAK do not cause Mal depletion. LPS-induced Mal degradation is blocked by IRAK1/4 inhibitor or IRAK1/IRAK4 knockdown. MyD88 is not a substrate for either IRAK. This phosphorylation-driven Mal degradation negatively regulates TLR2 and TLR4 signaling.\",\n      \"method\": \"In vitro kinase assay (direct phosphorylation of Mal by IRAK1/IRAK4); co-expression with kinase-inactive mutants; ubiquitination assay; LPS stimulation with IRAK1/4 inhibitor and siRNA knockdown\",\n      \"journal\": \"The Journal of biological chemistry\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1 / Moderate — in vitro kinase assay with mutagenesis controls, plus siRNA/pharmacological confirmation, single lab but multiple orthogonal methods\",\n      \"pmids\": [\"20400509\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2007,\n      \"finding\": \"IRAK-4 phosphorylates p47phox (NADPH oxidase cytosolic factor) at serine and threonine residues (Thr133, Ser288, Thr356 identified by tandem MS), distinct from PKC phosphorylation sites. IRAK-4-phosphorylated p47phox activates the NADPH oxidase in a cell-free system. Endogenous IRAK-4 co-immunoprecipitates with p47phox and co-localizes at the plasma membrane after LPS stimulation. IRAK-4 overexpression increases NADPH oxidase activity in response to LPS.\",\n      \"method\": \"In vitro kinase assay; tandem mass spectrometry; cell-free NADPH oxidase activation assay; co-immunoprecipitation; immunofluorescence co-localization; IRAK-4 overexpression\",\n      \"journal\": \"The Biochemical journal\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1 / Moderate — in vitro kinase assay with MS site identification, cell-free reconstitution, and Co-IP/imaging, single lab but multiple orthogonal methods\",\n      \"pmids\": [\"17217339\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2017,\n      \"finding\": \"IRAK4 is constitutively active as a kinase in resting cells; its intrinsic catalytic activity toward Pellino1 is not significantly increased by IL-1 stimulation. The IL-1-stimulated trans-autophosphorylation of IRAK4 is initiated by MyD88-induced dimerization rather than by an increase in intrinsic catalytic activity. In contrast, IRAK1 is inactive in unstimulated cells and activated by IL-1 or Pam3CSK4 through an allosteric mechanism dependent on its interaction with IRAK4, not by IRAK4-mediated phosphorylation.\",\n      \"method\": \"Pellino1 substrate-based kinase activity assays in human cell extracts; selective IRAK1 and IRAK4 pharmacological inhibitors; dephosphorylation/deubiquitylation experiments; IL-1R-expressing HEK293 cells, THP1 monocytes, primary macrophages\",\n      \"journal\": \"The Biochemical journal\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — novel cell-extract kinase assays with selective inhibitors across multiple cell types, single lab\",\n      \"pmids\": [\"28512203\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2017,\n      \"finding\": \"IRAK4 kinase activity controls TLR7/8-stimulated inflammatory cytokine production in human monocytes through activation of the transcription factor IRF5. IRAK4 inhibition abolishes IRF5 nuclear translocation and IRF5 binding to cytokine gene promoters. Mechanistically, IRAK4 kinase activity is required for IKKβ phosphorylation, which in turn activates IRF5; this pathway is distinct from canonical IKKβ-mediated IκB phosphorylation and NF-κB activation.\",\n      \"method\": \"Selective IRAK4 kinase inhibitor in primary human monocytes; transcriptomic analysis; biochemical IRF5 nuclear translocation assay; chromatin immunoprecipitation; IKKβ and TAK1 pharmacological inhibition\",\n      \"journal\": \"The Journal of biological chemistry\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — multiple orthogonal methods in primary human cells, single lab, no genetic validation of the IRF5 axis\",\n      \"pmids\": [\"28924041\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2019,\n      \"finding\": \"U2AF1 mutations cause retention of exon 4 in IRAK4 mRNA, producing a longer isoform (IRAK4-L) that assembles with the Myddosome more efficiently and results in maximal NF-κB activation, driving oncogenic signaling in MDS and AML. Inhibition of IRAK4-L abrogates leukemic cell growth.\",\n      \"method\": \"Global exon usage analysis in AML samples; functional expression of IRAK4-L vs short isoform; NF-κB activation assays; leukemic cell growth inhibition; U2AF1 mutant cell models\",\n      \"journal\": \"Nature cell biology\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — multiple orthogonal methods (splicing analysis, functional assays, growth inhibition) in patient-derived and cell-line models, single lab\",\n      \"pmids\": [\"31011167\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2019,\n      \"finding\": \"Crystal structures of unphosphorylated IRAK4 kinase domain in complex with ATP analog AMP-PNP (αC-out inactive conformation) and with type I inhibitors (DFG-in, αC-in active conformation) or type II inhibitors ponatinib/HG-12-6 (DFG-out conformation) reveal conformational flexibility of the unphosphorylated kinase. This flexibility allows unphosphorylated IRAK4 to adopt both active and inactive conformations depending on the bound ligand.\",\n      \"method\": \"X-ray crystallography of unphosphorylated IRAK4 kinase domain in multiple inhibitor-bound states (≤2.6 Å resolution); small-molecule screening for unphosphorylated IRAK4-selective inhibitors\",\n      \"journal\": \"The Journal of biological chemistry\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1 / Moderate — multiple high-resolution crystal structures with different bound ligands, single lab\",\n      \"pmids\": [\"30679311\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2004,\n      \"finding\": \"Prolonged stimulation of TLR2, TLR4, or TLR9 (but not TLR3) causes proteasome-dependent down-regulation of IRAK-4 protein and appearance of a 32-kDa C-terminal fragment, without affecting IRAK-4 mRNA levels. This down-regulation requires NF-κB activation and new protein synthesis and is blocked by proteasome inhibitors.\",\n      \"method\": \"Western blot analysis of IRAK-4 protein levels in RAW 264 macrophages after TLR stimulation; proteasome inhibitors; NF-κB inhibition; RT-PCR for mRNA levels\",\n      \"journal\": \"Journal of leukocyte biology\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 3 / Moderate — pharmacological dissection with multiple inhibitors, single cell line, no direct identification of the responsible protease\",\n      \"pmids\": [\"15258191\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2011,\n      \"finding\": \"Induction of endotoxin tolerance in vivo blocks TLR4-driven IRAK4 phosphorylation and activation in macrophages, while increasing expression of negative regulators IRAK-M, SHIP-1, and A20. Impaired IRAK4 activation correlates with reduced IκBα degradation, p38 phosphorylation, and cytokine expression.\",\n      \"method\": \"In vivo LPS tolerization mouse model; IRAK4 phosphorylation assay in peritoneal and splenic macrophages; RT-PCR for negative regulators; cytokine mRNA and protein measurements\",\n      \"journal\": \"Journal of leukocyte biology\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Weak — clean in vivo model with defined molecular readouts for IRAK4 phosphorylation status, single lab\",\n      \"pmids\": [\"21934070\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2021,\n      \"finding\": \"SARS-CoV-2-induced activation of human plasmacytoid dendritic cells (pDCs) and production of type I IFN, IL-6, and other cytokines critically depends on IRAK4 and UNC93B1, as established using pDCs from patients with genetic deficiencies in these proteins.\",\n      \"method\": \"Primary pDCs from IRAK4- and UNC93B1-deficient patients stimulated with live SARS-CoV-2 isolates; cytokine measurement; pDC subset diversification analysis\",\n      \"journal\": \"The Journal of experimental medicine\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — human genetic loss-of-function in primary cells with defined mechanistic readouts; replicated across multiple patients\",\n      \"pmids\": [\"33533916\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2016,\n      \"finding\": \"In pericytes, MyD88 and its downstream kinase IRAK4 intrinsically control pericyte migration and conversion to myofibroblasts (fibrogenic differentiation), independent of their roles in classical immune cells. Pericyte-specific MyD88 ablation or pharmacological IRAK4 inhibition in vivo protects against kidney fibrosis.\",\n      \"method\": \"Pericyte-specific MyD88 conditional knockout; pharmacological IRAK4 inhibitor in kidney injury models; pericyte migration and myofibroblast differentiation assays\",\n      \"journal\": \"The Journal of clinical investigation\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — cell-type-specific genetic deletion combined with pharmacological inhibition and in vivo fibrosis model, single lab\",\n      \"pmids\": [\"27869651\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2010,\n      \"finding\": \"Two human MyD88 death domain variants (S34Y and R98C) cause severely reduced NF-κB activation due to impaired MyD88 homo-oligomerization and reduced IRAK4 interaction. Structural modeling identifies Ser34 and Arg98 as residues important for Myddosome assembly. MyD88 homo-oligomerization and IRAK4 interaction are modulated by the MyD88 TIR domain and the IRAK4 kinase domain.\",\n      \"method\": \"Co-immunoprecipitation; NF-κB reporter assays; structural modeling of Myddosome assembly; receptor-specific signaling assays with MyD88 variants\",\n      \"journal\": \"The Journal of biological chemistry\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 3 / Moderate — Co-IP and functional assays with multiple receptor contexts, single lab, structural modeling not experimentally validated by crystallography\",\n      \"pmids\": [\"20966070\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2019,\n      \"finding\": \"Acetylation of IRAK4 at K34 and phosphorylation at T345/S346 are post-translational modifications induced by LPS/D-Gal stimulation in vivo; oridonin attenuates these modifications and protects against acute liver injury.\",\n      \"method\": \"Western blot with modification-specific antibodies; RNA-seq and KEGG pathway analysis; in vivo ALI mouse model\",\n      \"journal\": \"Mediators of inflammation\",\n      \"confidence\": \"Low\",\n      \"confidence_rationale\": \"Tier 3 / Weak — single lab, pharmacological intervention without direct identification of the acetyltransferase or phosphorylation writer for K34\",\n      \"pmids\": [\"31611735\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2009,\n      \"finding\": \"IRAK4 kinase activity is required for IL-1-mediated induction of IL-23R expression, STAT3 activation by IL-23, and Th17 differentiation. Adoptive transfer of IRAK4 kinase-inactive Th17 cells fails to induce EAE, demonstrating a T-cell-intrinsic requirement for IRAK4 kinase activity in Th17-mediated autoimmunity.\",\n      \"method\": \"IRAK4 kinase-inactive knock-in mice; EAE model; adoptive transfer of Th17 cells; flow cytometry; cytokine assays; IL-23R expression analysis\",\n      \"journal\": \"Journal of immunology\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — knock-in mice with adoptive transfer experiments and multiple readouts, single lab\",\n      \"pmids\": [\"19542468\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2021,\n      \"finding\": \"IRAK4 phosphorylates IRF5 and IRF4 in microglia (confirmed by Co-IP showing IRAK4 forms a Myddosome with MyD88/IRF5/IRF4); IRAK4 inhibition blocks IRF5/IRF4 nuclear translocation and quenches pro-inflammatory microglial responses to ischemia, improving neuronal viability.\",\n      \"method\": \"Co-immunoprecipitation of IRAK4/MyD88/IRF5/IRF4 complex; IRAK4 inhibitor (ND2158); nuclear translocation assay by immunofluorescence; ELISA for cytokines; oxygen-glucose deprivation model\",\n      \"journal\": \"Cells\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 3 / Moderate — Co-IP of complex plus functional inhibitor experiments, but direct phosphorylation of IRFs by IRAK4 not demonstrated in vitro in this study\",\n      \"pmids\": [\"33573200\"],\n      \"is_preprint\": false\n    }\n  ],\n  \"current_model\": \"IRAK4 is a serine/threonine kinase that functions as the master upstream kinase in the TLR/IL-1R signaling cascade: upon receptor activation, IRAK4 is recruited to the membrane-proximal Myddosome — a left-handed helical oligomer of MyD88, IRAK4, and IRAK2/IRAK1 death domains — where Myddosome assembly drives IRAK4 kinase domain dimerization and trans-autophosphorylation, activating IRAK4 and enabling it to phosphorylate downstream substrates (including IRAK1, Mal/TIRAP, Pellino1/2, p47phox, and IRF5), ultimately leading to NF-κB, MAPK, and IRF5 activation and inflammatory cytokine production; IRAK4 also exerts a kinase-independent scaffold function essential for Myddosome stability and TRAF6 activation, and its activity is regulated by prolonged TLR stimulation via proteasomal degradation and by miRNA-mediated downregulation.\"\n}\n```","stage2_raw":"{\n  \"mechanistic_narrative\": \"IRAK4 is the apical serine/threonine kinase of the Toll-like receptor (TLR) and IL-1 receptor (IL-1R) innate immune signaling cascade, indispensable in vivo for responses to LPS and microbial challenge [#1]. Upon receptor engagement, IRAK4 is recruited to the membrane-proximal Myddosome, a left-handed helical death-domain oligomer of 6 MyD88, 4 IRAK4, and 4 IRAK2/IRAK1 subunits assembled hierarchically as MyD88 first recruits IRAK4, which then recruits its IRAK substrates [#0]. Myddosome-driven dimerization of the IRAK4 kinase domain enables trans-autophosphorylation across the activation loop and is required for ligand-dependent signaling; activation reflects MyD88-induced dimerization rather than a change in intrinsic catalytic activity, since IRAK4 is constitutively active toward Pellino1 in resting cells [#2, #13]. Active IRAK4 phosphorylates and recruits IRAK1, and its substrate repertoire includes Pellino2, the adaptor Mal/TIRAP (driving its ubiquitination and proteasomal degradation as a negative feedback on TLR2/4), and the NADPH oxidase factor p47phox [#3, #10, #11, #12]. Downstream, IRAK4 nucleates a Pellino1–IRAK–TRAF6 complex bridging the receptor and TAK1, and its kinase activity drives IKK\\u03b2-dependent IRF5 activation for inflammatory cytokine transcription [#9, #14]. IRAK4 additionally performs a kinase-independent scaffold function: kinase-inactive IRAK4 retains association with MyD88 and supports NF-\\u03baB/MAPK activation and TRAF6 activation from both MyD88- and TRIF-dependent TLR4 arms, while kinase activity primarily tunes signal strength and inflammatory cytokine output [#5, #6, #7, #8]. IRAK4 activity is downregulated by prolonged TLR stimulation via proteasomal degradation and by induction of negative regulators during endotoxin tolerance [#17, #18]. A U2AF1-mutant splice isoform (IRAK4-L) assembles more efficiently with the Myddosome to drive oncogenic NF-\\u03baB signaling in MDS/AML [#15].\",\n  \"teleology\": [\n    {\n      \"year\": 2002,\n      \"claim\": \"Established IRAK4 as a non-redundant, essential kinase in innate immunity rather than one of several interchangeable signaling components.\",\n      \"evidence\": \"Gene-targeted IRAK4-knockout mice challenged with LPS and microbial pathogens\",\n      \"pmids\": [\"11923871\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Did not resolve whether catalytic activity or scaffolding accounts for the phenotype\", \"No molecular structure of how IRAK4 engages the receptor complex\"]\n    },\n    {\n      \"year\": 2002,\n      \"claim\": \"Placed IRAK4 within a defined signal-dependent complex, identifying Pellino1 as a partner bridging the receptor to the TAK1 module.\",\n      \"evidence\": \"Co-IP and NF-\\u03baB/IL-8 reporter assays of a Pellino1\\u2013IRAK1\\u2013IRAK4\\u2013TRAF6 complex\",\n      \"pmids\": [\"12496252\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"No reconstitution or structural validation of complex stoichiometry\", \"Direct substrate relationship not established here\"]\n    },\n    {\n      \"year\": 2003,\n      \"claim\": \"Identified Pellino2 as a direct IRAK4 substrate, extending IRAK4's catalytic repertoire beyond the IRAK kinases.\",\n      \"evidence\": \"Yeast two-hybrid, Co-IP, and in vitro kinase assay showing Pellino2 phosphorylation\",\n      \"pmids\": [\"12860405\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Phosphosites not mapped\", \"Functional consequence of Pellino2 phosphorylation not defined\"]\n    },\n    {\n      \"year\": 2004,\n      \"claim\": \"Dissected kinase versus scaffold contributions, showing IRAK4 is required to recruit and activate IRAK1 but that kinase-inactive IRAK4 still supports partial signaling.\",\n      \"evidence\": \"Reciprocal reconstitution of IRAK4-deficient cells with WT vs kinase-inactive IRAK4; NF-\\u03baB/JNK and cytokine readouts\",\n      \"pmids\": [\"15292196\", \"15084582\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Did not establish in vivo physiological weight of kinase vs scaffold roles\", \"Redundancy with IRAK1 kinase activity left the catalytic requirement ambiguous\"]\n    },\n    {\n      \"year\": 2004,\n      \"claim\": \"Revealed that IRAK4 protein levels are actively controlled, linking prolonged TLR signaling to proteasomal turnover of the kinase.\",\n      \"evidence\": \"Western blot of IRAK4 levels in macrophages after sustained TLR stimulation with proteasome and NF-\\u03baB inhibitors\",\n      \"pmids\": [\"15258191\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Responsible protease/E3 ligase not identified\", \"Single cell line; in vivo relevance not tested\"]\n    },\n    {\n      \"year\": 2007,\n      \"claim\": \"Demonstrated in vivo that IRAK4 catalytic activity is required for TLR-driven inflammation and type I IFN, settling that the kinase function is physiologically essential.\",\n      \"evidence\": \"IRAK4 kinase-inactive knock-in mice in LPS/CpG shock; pDC IFN and mRNA-stability assays\",\n      \"pmids\": [\"17470642\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Did not define the direct substrates mediating cytokine mRNA stability\", \"Mechanism of IRF/IFN induction not mapped\"]\n    },\n    {\n      \"year\": 2007,\n      \"claim\": \"Connected IRAK4 to the NADPH oxidase by identifying p47phox as a direct, site-specific substrate, broadening IRAK4 output beyond transcription factors.\",\n      \"evidence\": \"In vitro kinase assay with MS phosphosite mapping, cell-free oxidase reconstitution, Co-IP and membrane co-localization\",\n      \"pmids\": [\"17217339\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"In vivo contribution of IRAK4-p47phox phosphorylation to oxidative burst not quantified\"]\n    },\n    {\n      \"year\": 2009,\n      \"claim\": \"Extended IRAK4 kinase function to adaptive immunity, showing a T-cell-intrinsic requirement for Th17 differentiation and autoimmunity.\",\n      \"evidence\": \"Kinase-inactive knock-in mice, Th17 adoptive transfer, and EAE model\",\n      \"pmids\": [\"19542468\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Direct IRAK4 substrate in T cells not identified\", \"Single autoimmune model\"]\n    },\n    {\n      \"year\": 2010,\n      \"claim\": \"Provided the structural basis for IRAK4 recruitment by resolving the Myddosome as a defined helical death-domain oligomer with hierarchical assembly.\",\n      \"evidence\": \"X-ray crystallography of the MyD88\\u2013IRAK4\\u2013IRAK2 death-domain complex with composite-site mutagenesis\",\n      \"pmids\": [\"20485341\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Did not resolve how kinase domains are activated within the assembled complex\", \"Dynamics of assembly/disassembly not captured\"]\n    },\n    {\n      \"year\": 2010,\n      \"claim\": \"Established a negative-feedback role for IRAK4 catalysis by showing it phosphorylates Mal/TIRAP to trigger its degradation, while excluding MyD88 as a substrate.\",\n      \"evidence\": \"In vitro kinase, ubiquitination, and LPS-stimulation assays with kinase-inactive mutants and inhibitor/siRNA\",\n      \"pmids\": [\"20400509\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"E3 ligase mediating Mal ubiquitination not identified here\", \"Quantitative impact on signal duration not measured\"]\n    },\n    {\n      \"year\": 2014,\n      \"claim\": \"Defined the activation mechanism, showing Myddosome-driven kinase-domain dimerization positions activation loops for trans-autophosphorylation.\",\n      \"evidence\": \"Biophysical dimerization assays, crystal structure of the unphosphorylated kinase domain dimer, and signaling assays with dimerization mutants\",\n      \"pmids\": [\"25201411\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Did not address whether intrinsic catalytic activity changes upon activation\", \"Substrate selection in the dimer not defined\"]\n    },\n    {\n      \"year\": 2017,\n      \"claim\": \"Reframed IRAK4 activation as proximity-driven rather than catalysis-switched, showing IRAK4 is constitutively active and activates IRAK1 allosterically.\",\n      \"evidence\": \"Pellino1 substrate-based kinase assays in cell extracts with selective IRAK1/IRAK4 inhibitors across multiple cell types\",\n      \"pmids\": [\"28512203\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Cell-extract assay; physiological substrate kinetics not measured\", \"Single lab\"]\n    },\n    {\n      \"year\": 2017,\n      \"claim\": \"Identified an IKK\\u03b2\\u2013IRF5 axis downstream of IRAK4 kinase activity, distinct from canonical NF-\\u03baB activation, for TLR7/8 cytokine output.\",\n      \"evidence\": \"Selective IRAK4 inhibitor in primary human monocytes with IRF5 translocation, ChIP, and IKK\\u03b2/TAK1 inhibitor studies\",\n      \"pmids\": [\"28924041\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"No genetic validation of the IRF5 axis\", \"Direct IRAK4 substrate upstream of IKK\\u03b2 not defined\"]\n    },\n    {\n      \"year\": 2018,\n      \"claim\": \"Established that the IRAK4 scaffold function dominates IL-1 signaling and that kinase activity primarily tunes complex assembly and signal strength.\",\n      \"evidence\": \"Co-IP of IRAK4 variants with MyD88/IRAK1 and reconstitution/cytokine assays using kinase-dead and MyD88-binding-deficient variants\",\n      \"pmids\": [\"30115681\", \"30076215\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Quantitative contribution of scaffold vs kinase across receptors not fully resolved\", \"Single lab for each dissection\"]\n    },\n    {\n      \"year\": 2019,\n      \"claim\": \"Linked IRAK4 to malignancy via a U2AF1-driven splice isoform (IRAK4-L) that hyperassembles with the Myddosome to drive oncogenic NF-\\u03baB signaling.\",\n      \"evidence\": \"Exon-usage analysis, functional isoform expression, NF-\\u03baB and leukemic growth assays in patient-derived and mutant models\",\n      \"pmids\": [\"31011167\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Structural basis of enhanced IRAK4-L Myddosome incorporation not resolved\", \"Therapeutic dependence beyond cell models not established\"]\n    },\n    {\n      \"year\": 2019,\n      \"claim\": \"Characterized the conformational plasticity of unphosphorylated IRAK4, informing type I vs type II inhibitor design.\",\n      \"evidence\": \"Multiple crystal structures of the unphosphorylated kinase domain bound to AMP-PNP and inhibitors\",\n      \"pmids\": [\"30679311\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Functional consequence of conformational states in cells not measured\"]\n    },\n    {\n      \"year\": 2022,\n      \"claim\": \"Extended the IRAK4 scaffold requirement to the TRIF arm of TLR4, positioning IRAK4 as an integrator of MyD88- and TRIF-dependent TRAF6 activation.\",\n      \"evidence\": \"Genetic epistasis in IRAK4-deficient cells plus kinase-inhibitor dissection of TRAF6 activation\",\n      \"pmids\": [\"35977521\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Mechanism of IRAK4 engagement with the TRIF pathway not defined\", \"Single lab; limited orthogonal validation\"]\n    },\n    {\n      \"year\": null,\n      \"claim\": \"How the IRAK4 kinase domain selects among its diverse substrates (IRAK1, Pellino1/2, Mal, p47phox, IRF5) within the Myddosome, and how acetylation and other post-translational modifications regulate IRAK4 in vivo, remain unresolved.\",\n      \"evidence\": \"\",\n      \"pmids\": [],\n      \"confidence\": \"Low\",\n      \"gaps\": [\"Writers/erasers of IRAK4 K34 acetylation and T345/S346 phosphorylation not identified\", \"Direct in vitro phosphorylation of IRF5/IRF4 by IRAK4 not demonstrated\", \"Rules governing substrate selection in the activated dimer unknown\"]\n    }\n  ],\n  \"mechanism_profile\": {\n    \"molecular_activity\": [\n      {\"term_id\": \"GO:0140096\", \"supporting_discovery_ids\": [3, 10, 11, 12]},\n      {\"term_id\": \"GO:0016740\", \"supporting_discovery_ids\": [2, 11, 12]},\n      {\"term_id\": \"GO:0140657\", \"supporting_discovery_ids\": [2, 16]},\n      {\"term_id\": \"GO:0060089\", \"supporting_discovery_ids\": [0, 1]},\n      {\"term_id\": \"GO:0060090\", \"supporting_discovery_ids\": [5, 6, 7]}\n    ],\n    \"localization\": [\n      {\"term_id\": \"GO:0005886\", \"supporting_discovery_ids\": [12]},\n      {\"term_id\": \"GO:0005829\", \"supporting_discovery_ids\": [2, 13]}\n    ],\n    \"pathway\": [\n      {\"term_id\": \"R-HSA-168256\", \"supporting_discovery_ids\": [1, 4, 19]},\n      {\"term_id\": \"R-HSA-162582\", \"supporting_discovery_ids\": [0, 3, 9]},\n      {\"term_id\": \"R-HSA-1643685\", \"supporting_discovery_ids\": [15, 20]}\n    ],\n    \"complexes\": [\"Myddosome (MyD88-IRAK4-IRAK2/IRAK1)\", \"Pellino1-IRAK-IRAK4-TRAF6 complex\"],\n    \"partners\": [\"MyD88\", \"IRAK1\", \"IRAK2\", \"TRAF6\", \"Pellino1\", \"Pellino2\", \"TIRAP\", \"IRF5\"],\n    \"other_free_text\": []\n  }\n}","audit_flag":null,"evaluation":{"pairwise":"win","faith_supported":8,"faith_total":8,"faith_pct":100.0}}