{"gene":"MAP3K8","run_date":"2026-06-10T02:59:50","timeline":{"discoveries":[{"year":1996,"finding":"TPL-2/MAP3K8 directly phosphorylates and activates MEK-1 and SEK-1 (MAP kinase kinases) in vitro, functioning as a MAP kinase kinase kinase that activates both the ERK and JNK/SAPK pathways.","method":"In vitro kinase assay with immunoprecipitated TPL-2 and recombinant GST-MEK-1/SEK-1 fusion proteins; transfection of COS-1 and Jurkat T cells showing ERK-1 and SAP kinase activation","journal":"The EMBO journal","confidence":"High","confidence_rationale":"Tier 1 / Strong — direct in vitro kinase assay reconstituted with purified proteins, replicated in multiple cell lines","pmids":["8631303"],"is_preprint":false},{"year":1994,"finding":"MAP3K8/Tpl-2-induced MAPK activation is blocked by dominant-negative mutants of Ras and Raf-1, and kinase-deficient Tpl-2 down-regulates mitogenic signals from v-Ha-Ras or v-Raf, placing Tpl-2 in the Ras/Raf-1 signaling complex.","method":"Dominant-negative mutant co-transfection epistasis in cell lines","journal":"Proceedings of the National Academy of Sciences of the United States of America","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — genetic epistasis with dominant-negative constructs, single lab, two complementary approaches","pmids":["7937886"],"is_preprint":false},{"year":1997,"finding":"C-terminal truncation of Tpl-2 increases catalytic activity ~7-fold and enhances MAPK/SAPK pathway activation 2-3 fold; the C-terminal tail interacts with the truncated kinase domain (GST fusion co-expression in Sf9 cells) and mediates autoinhibitory intramolecular interactions that down-regulate kinase activity.","method":"In vitro kinase assay comparing wild-type and truncated Tpl-2; GST pulldown of C-terminal tail with truncated protein in Sf9 cells; transgenic mouse model","journal":"Genes & development","confidence":"High","confidence_rationale":"Tier 1 / Strong — in vitro kinase assay with mutagenesis, protein interaction confirmed by co-expression pulldown, functional validation in transgenic mice","pmids":["9087424"],"is_preprint":false},{"year":1999,"finding":"TPL-2 forms a complex with the C-terminus of NF-κB1 p105; TPL-2 expression causes phosphorylation and increased degradation of p105 while maintaining p50 production, thereby releasing associated Rel subunits to generate active nuclear NF-κB. Kinase-inactive TPL-2 blocks TNF-α-induced p105 degradation.","method":"Co-immunoprecipitation; transfection with wild-type and kinase-inactive TPL-2; p105 phosphorylation and degradation assays","journal":"Nature","confidence":"High","confidence_rationale":"Tier 2 / Strong — reciprocal Co-IP, kinase-dead mutant rescue, multiple orthogonal methods, published in Nature","pmids":["9950430"],"is_preprint":false},{"year":2003,"finding":"NF-κB1 p105 negatively regulates TPL-2 MEK kinase activity through two distinct interactions: the TPL-2 C-terminus binds p105 residues 497–534, while the TPL-2 kinase domain interacts with the p105 death domain. Binding to the p105 death domain inhibits TPL-2 MEK kinase activity in vitro, and both interactions are required for full inhibition in cells. C-terminally truncated oncogenic TPL-2 is insensitive to this inhibition. TPL-2 stability in vivo depends on its high-affinity stoichiometric association with p105.","method":"In vitro kinase assay; co-immunoprecipitation mapping of binding domains; cotransfection experiments with C-terminal deletion mutants","journal":"Molecular and cellular biology","confidence":"High","confidence_rationale":"Tier 1 / Strong — in vitro kinase assay combined with domain-mapping Co-IP and mutagenesis, multiple orthogonal methods","pmids":["12832462"],"is_preprint":false},{"year":2004,"finding":"LPS stimulation releases both forms of TPL-2 from the p105 complex, and TPL-2 MEK kinase activity is restricted to the p105-free pool. IKK complex phosphorylation of two serines in the p105 PEST region triggers proteasome-mediated p105 proteolysis, which is essential for TPL-2 release and subsequent activation of MEK and ERK. Expression of a p105 point mutant not susceptible to signal-induced proteolysis impairs LPS-induced TPL-2 activation; wild-type but not mutant p105 reconstitutes LPS-stimulated MEK/ERK signaling in NF-κB1-deficient macrophages.","method":"Co-immunoprecipitation; pharmacological IKK blockade; reconstitution in primary NF-κB1-deficient macrophages with wild-type vs. IKK-site mutant p105; proteasome inhibitors","journal":"Molecular and cellular biology","confidence":"High","confidence_rationale":"Tier 1 / Strong — reconstitution in primary macrophages with site-specific mutants, multiple orthogonal methods, mechanistically definitive","pmids":["15485931"],"is_preprint":false},{"year":2004,"finding":"ABIN-2 forms a ternary complex with TPL-2 and NF-κB1 p105. ABIN-2 is required for TPL-2 protein stability: RNAi depletion of ABIN-2 dramatically reduces steady-state TPL-2 protein without affecting TPL-2 mRNA or p105 levels, and ABIN-2 increases TPL-2 half-life. LPS activation of TPL-2 correlates with its release from ABIN-2.","method":"Affinity purification identifying ABIN-2 as novel p105-associated protein; co-immunoprecipitation of endogenous proteins in bone marrow-derived macrophages; RNA interference; pulse-chase half-life experiments","journal":"Molecular and cellular biology","confidence":"High","confidence_rationale":"Tier 2 / Strong — affinity purification, reciprocal Co-IP of endogenous proteins, RNAi with protein stability readout, replicated in primary macrophages","pmids":["15169888"],"is_preprint":false},{"year":2007,"finding":"LPS stimulation induces phosphorylation of serine 400 in the TPL-2 C-terminal tail. Mutation of S400 to alanine blocks LPS-stimulated TPL-2 MEK kinase activity and ERK activation independently of p105 release, demonstrating that S400 phosphorylation is a second required regulatory step for TPL-2 activation. C-terminal truncations that remove S400 may contribute to oncogenic activation.","method":"Site-directed mutagenesis (S400A); retroviral reconstitution in Nfkb1-/- and Map3k8-/- macrophages; in vitro MEK kinase assay","journal":"Molecular and cellular biology","confidence":"High","confidence_rationale":"Tier 1 / Strong — in vitro kinase assay with site-directed mutagenesis, reconstitution in two knockout cell backgrounds","pmids":["17709378"],"is_preprint":false},{"year":2012,"finding":"IκB kinase 2 (IKK2) directly phosphorylates TPL-2 on serine 400, providing the transphosphorylation signal required for TPL-2 activation of ERK-1/2 independently of p105 regulation. The IKK complex therefore controls both key regulatory steps of TPL-2 activation: p105 proteolysis and TPL-2 S400 phosphorylation.","method":"In vitro kinase assay with recombinant IKK2 and TPL-2 substrates; site-directed mutagenesis; pharmacological IKK2 inhibition in macrophages","journal":"Molecular and cellular biology","confidence":"High","confidence_rationale":"Tier 1 / Strong — in vitro kinase reconstitution with recombinant proteins plus mutagenesis and pharmacological validation","pmids":["22988300"],"is_preprint":false},{"year":2014,"finding":"IKK-mediated phosphorylation of TPL-2 S400 cooperates with TPL-2 S443 autophosphorylation to trigger TPL-2 association with 14-3-3 proteins. 14-3-3 binding to the phosphorylated C-terminus stimulates TPL-2 MEK-1 kinase activity and is essential for ERK-1/2 activation and LPS-induced TNF production. C-terminal deletion of TPL-2 renders its kinase activity independent of 14-3-3, contributing to oncogenic transformation.","method":"Co-immunoprecipitation of TPL-2 and 14-3-3; site-directed mutagenesis of S400 and S443; in vitro MEK-1 kinase assay; retroviral reconstitution in Map3k8-/- macrophages","journal":"Proceedings of the National Academy of Sciences of the United States of America","confidence":"High","confidence_rationale":"Tier 1 / Strong — in vitro kinase assay, Co-IP, mutagenesis of two sites, reconstitution in knockout macrophages","pmids":["24912162"],"is_preprint":false},{"year":2012,"finding":"IKK-induced proteolysis of NF-κB1 p105 (via IKK phosphorylation of p105 PEST serines) is essential for TPL-2/ERK activation by multiple TLR ligands (LPS, CpG, Pam3CSK, poly(I·C), flagellin, R848) and by TNF. Mutation of the IKK target serines on p105 (SSAA) blocks agonist-induced TPL-2 release from p105 and ERK activation. TPL-2/ERK activation creates a negative feedback loop to suppress IL-12 expression.","method":"Knock-in mouse model (Nfkb1-SSAA/SSAA); macrophage stimulation with multiple TLR ligands; ERK phosphorylation assays; gene expression analysis","journal":"Molecular and cellular biology","confidence":"High","confidence_rationale":"Tier 2 / Strong — physiological knock-in mouse model with multiple TLR ligands tested, mechanistically definitive, multiple orthogonal readouts","pmids":["22733995"],"is_preprint":false},{"year":2016,"finding":"TPL-2 catalytic activity is required for phosphorylation of MKK3 and MKK6 activation loops (but not MKK4) downstream of TLR4 and TNF stimulation in macrophages, placing TPL-2 as the MAP3K for the MKK3/6-p38α axis in addition to the MKK1/2-ERK axis. MKK3/6 activation also requires IKK phosphorylation of NF-κB1 p105. TNF activation of p38α is substantially dependent on TPL-2 via MKK3/6.","method":"Quantitative mass spectrometry of protein phosphorylation in wild-type vs. Map3k8-D270A/D270A (kinase-dead) macrophages following LPS/TNF/bacterial stimulation","journal":"The Biochemical journal","confidence":"High","confidence_rationale":"Tier 1 / Strong — quantitative phosphoproteomics with kinase-dead knock-in model, unbiased substrate identification","pmids":["27402796"],"is_preprint":false},{"year":1998,"finding":"TPL-2 activates the NFAT transcription factor and induces IL-2 expression in T-cell lines via convergence of the MAPK and calcineurin/NFAT pathways. NFATp (but not NFATc or NFATx) undergoes nuclear translocation when co-expressed with wild-type Tpl-2. Kinase-dead Tpl-2 K167M inhibits anti-CD3-stimulated NFAT activation in Jurkat cells. TPL-2 also activates NF-κB to cooperate in IL-2 promoter induction.","method":"Transfection with dominant-negative signaling molecules; NFAT-driven reporter assays; nuclear translocation assay; specific isoform co-expression","journal":"Proceedings of the National Academy of Sciences of the United States of America","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — kinase-dead mutant plus reporter assays and nuclear localization, single lab","pmids":["9520452"],"is_preprint":false},{"year":2002,"finding":"TPL-2/Cot interacts with TRAF2 (co-immunoprecipitation and co-localization), functioning downstream of TRAF2, and contributes to LMP1-induced NF-κB signaling. Catalytically inactive TPL-2 suppresses LMP1- and CD40-induced NF-κB activation. TPL-2 modulates both IκBα and p105 functions in this pathway.","method":"Co-immunoprecipitation; co-localization; dominant-negative kinase-dead TPL-2 transfection; NF-κB reporter assay","journal":"Journal of virology","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — reciprocal Co-IP plus kinase-dead functional assay, single lab","pmids":["11932422"],"is_preprint":false},{"year":2005,"finding":"MAP3K8/Tpl-2 is recruited to the CD40 receptor complex through TRAF-binding sites in CD40 (TRAF-dependent association). Catalytically inactive Tpl-2 suppresses CD40-mediated IKK activation and NF-κB induction. Tpl2-/- fibroblasts are deficient in CD40 but not TNF signaling. Tpl-2 functions distal to TRAFs but proximal to the TAK1/TAB1 complex.","method":"Co-immunoprecipitation of Tpl-2 with CD40 complex; kinase-dead dominant-negative transfection; Tpl2-/- fibroblast genetic experiments; epistasis with TAK1/TAB1","journal":"Biochemical and biophysical research communications","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — Co-IP, knockout fibroblasts, dominant-negative epistasis, single lab","pmids":["15670770"],"is_preprint":false},{"year":2009,"finding":"TPL-2 negatively regulates LPS- and CpG-induced IFN-β production in macrophages and myeloid DCs via ERK-dependent induction of c-Fos. In the absence of TPL-2 signaling, IFN-β is increased while IL-10 is decreased. The negative regulation requires protein synthesis and is independent of IL-10.","method":"Map3k8-/- macrophages and myeloid DCs; retroviral transduction of ERK-dependent transcription factor c-Fos into TPL-2-deficient cells; cytokine secretion assays","journal":"The Journal of experimental medicine","confidence":"High","confidence_rationale":"Tier 2 / Strong — knockout primary cells plus reconstitution with downstream effector, multiple TLR ligands tested, mechanistically defined","pmids":["19667062"],"is_preprint":false},{"year":2010,"finding":"Arginine availability facilitates TPL-2 activation downstream of TLR4 by preventing dephosphorylation and inactivation of TPL-2 in LPS-stimulated macrophages, thereby enabling ERK1/2 activation and TNF-α production. Arginine starvation impairs LPS-induced ERK1/2 activation in vivo.","method":"Arginine depletion/supplementation experiments in cultured macrophages and in mice; ERK1/2 and TPL-2 phosphorylation assays; in vivo arginine supplementation","journal":"Science signaling","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — both in vitro and in vivo validation, single lab, mechanistic follow-up limited to phosphorylation assays","pmids":["20716763"],"is_preprint":false},{"year":2001,"finding":"Tpl-2 induces apoptosis by promoting assembly of a complex containing caspase-9, the ankyrin repeat protein Tvl-1, and procaspase-3, leading to caspase-9-dependent caspase-3 activation. Co-expression with Tvl-1 enhances this effect; procaspase-3 conditionally associates with Tvl-1 in response to Tpl-2 apoptotic signals.","method":"Co-immunoprecipitation of complex components; caspase activity assays; co-transfection in non-transformed cells","journal":"Journal of cellular physiology","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — Co-IP of complex plus functional caspase assay, single lab","pmids":["11267997"],"is_preprint":false},{"year":2019,"finding":"BCL-3, a nuclear IκB protein, promotes TPL-2 degradation by increasing TPL-2 nuclear localization. TPL-2 is a nucleocytoplasmic shuttling protein, and the nucleus is the primary site for its proteasomal degradation after TLR stimulation. BCL-3 interacts with TPL-2 and promotes nuclear retention, thereby limiting MAPK activity. Bcl3-/- macrophages have increased TPL-2 stability, elevated MAPK activity, and lower TLR stimulation threshold for cytokine production.","method":"Bcl3-/- macrophages; co-immunoprecipitation of BCL-3 and TPL-2; subcellular fractionation; nuclear localization imaging; proteasome inhibitor experiments","journal":"Proceedings of the National Academy of Sciences of the United States of America","confidence":"High","confidence_rationale":"Tier 2 / Strong — knockout primary cells, Co-IP, subcellular fractionation with functional consequence, multiple orthogonal methods","pmids":["31772019"],"is_preprint":false},{"year":2021,"finding":"TPL-2 catalytic activity induces phagosome acidification and proteolysis in macrophages through a MAP kinase-independent mechanism. TPL-2 stimulates phosphorylation of DMXL1 (a V-ATPase regulator), promoting V-ATPase assembly on phagosomes. Blocking TPL-2 catalytic activity reduces V-ATPase proton pump subunit abundance on phagosomes and impairs killing of S. aureus and C. rodentium.","method":"Map3k8-D270A/D270A kinase-dead macrophages; quantitative phagosome proteomics; latex bead phagosome assay; bacterial killing assay; V-ATPase assembly analysis; DMXL1 phosphorylation","journal":"The EMBO journal","confidence":"High","confidence_rationale":"Tier 1 / Strong — quantitative proteomics with kinase-dead mutant, novel substrate (DMXL1) identification, functional bacterial killing assay in both mouse and human macrophages","pmids":["33881780"],"is_preprint":false},{"year":2009,"finding":"Tpl-2 wild-type protein interacts with p53 in vitro and in cells. Overexpression of Tpl-2 inhibits EGF-induced p53 phosphorylation (Ser15) by upregulating protein phosphatase 2A activity. Mutation S413A in Tpl-2 abrogates suppression of p53 activity and EGF-induced c-fos promoter/AP-1 transactivation.","method":"Co-immunoprecipitation of Tpl-2 and p53 in vitro and ex vivo; site-directed mutagenesis (S413A); p53 phosphorylation and transcriptional activity assays","journal":"Carcinogenesis","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — Co-IP plus mutagenesis, single lab, mechanistic follow-up via PP2A","pmids":["19221002"],"is_preprint":false},{"year":2022,"finding":"TPL-2 (MAP3K8) activation promotes Th1-like differentiation and constitutively activates MEK-ERK signaling in HTLV-1-infected T cells. HTLV-1 Tax, Fosl2, and c-Jun collaboratively induce chromatin remodeling at the MAP3K8 enhancer locus, driving MAP3K8 overexpression. MEK inhibitors suppress the MAP3K8-MEK signaling cascade and mitigate inflammatory pathogenesis ex vivo.","method":"Chromatin accessibility profiling (ATAC-seq); transcriptomic analysis; chromatin immunoprecipitation; MEK inhibitor treatment in ex vivo culture; overexpression of Tax, Fosl2, c-Jun","journal":"Nature communications","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — chromatin profiling plus functional inhibitor validation, single lab, novel mechanism for MAP3K8 transcriptional regulation","pmids":["41213906"],"is_preprint":false},{"year":2022,"finding":"TPL-2 inhibition of IFN-β in TLR4-stimulated macrophages is mediated via an ERK1/2-TCF-FOS axis. TPL-2 activates ERK1/2, which phosphorylates ELK1 (a ternary complex factor) and induces TCF target genes including FOS. TCFs mediate approximately half of the transcriptional output of TPL-2 signaling, partially via secondary transcription factors. Loss of FOS recapitulates a significant fraction of TPL-2 transcriptional regulation.","method":"Transcriptomic comparison of wild-type vs. Map3k8-D270A/D270A macrophages; TCF-deficient macrophages; Fos-/- macrophages; bioinformatics motif analysis; ELK1 phosphorylation assay","journal":"Journal of immunology (Baltimore, Md. : 1950)","confidence":"High","confidence_rationale":"Tier 2 / Strong — kinase-dead knock-in plus multiple transcription factor knockouts, genome-wide transcriptomics, mechanistic pathway delineation","pmids":["35082159"],"is_preprint":false},{"year":2020,"finding":"MAP3K8 regulates Cox-2 expression and PGE2 production in macrophages in the lung. Map3k8 deficiency in mice reduces Cox-2 expression and PGE2 levels; macrophage-specific deletion of Map3k8 is sufficient to exacerbate pulmonary fibrosis. Exogenous PGE2 administration rescues the exacerbated fibrotic phenotype of Map3k8-/- mice.","method":"Conditional macrophage-specific Map3k8 knockout (LysM-Cre); bone marrow transplantation; bleomycin fibrosis model; Cox-2 and PGE2 measurements; PGE2 rescue experiment","journal":"Journal of immunology (Baltimore, Md. : 1950)","confidence":"High","confidence_rationale":"Tier 2 / Strong — cell-type-specific conditional knockout plus bone marrow transfer plus pharmacological rescue, multiple orthogonal approaches","pmids":["33443087"],"is_preprint":false},{"year":2018,"finding":"Hypoxia increases MAP3K8 expression via HIF-1 (hypoxia-induced factor) transcriptional activation, upstream of the p38 MAPK pathway in monocyte-derived dendritic cells. MAP3K8 knockdown or pharmacological inhibition reduces hypoxia-potentiated TNF-α secretion and p38 MAPK phosphorylation.","method":"siRNA knockdown of MAP3K8 in human moDCs; MAP3K8 inhibitor; TNF-α ELISA; p38 phosphorylation assay; HIF-ChIP or HIF-target analysis","journal":"Bioscience reports","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — siRNA knockdown plus inhibitor, single lab, functional readout","pmids":["30463908"],"is_preprint":false},{"year":2019,"finding":"MAP3K8 fusions in spitzoid melanoma invariably encode the intact kinase domain but lack the autoinhibitory C-terminal exon (exon 1-8 fusions), resulting in constitutively active kinase. These truncating rearrangements activate MEK signaling and confer sensitivity to MEK inhibition.","method":"RNA sequencing identification of fusion transcripts; clinical MEK inhibitor treatment with tumor response; FISH break-apart assay","journal":"Nature medicine","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — RNA-seq structural characterization in large patient cohort, clinical MEK inhibitor response, mechanistic inference supported by known C-terminal autoinhibition","pmids":["30833747"],"is_preprint":false},{"year":2019,"finding":"Truncating MAP3K8 rearrangements in driver-negative melanoma cell lines result in increased levels of truncated, constitutively active MAP3K8 protein, oncogenic ERK dependency, resistance to BRAF inhibition, and sensitivity to MEK or ERK1/2 inhibition.","method":"Endogenous MAP3K8 rearranged melanoma cell lines; FISH validation; western blot of truncated protein; MEK/ERK inhibitor sensitivity assays; BRAF inhibitor resistance assay","journal":"Molecular cancer research : MCR","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — endogenous rearrangements in cell lines with biochemical and pharmacological characterization, single lab","pmids":["31186280"],"is_preprint":false},{"year":2015,"finding":"MAP3K8 overexpression in high-grade serous ovarian carcinoma cells controls cancer cell proliferation and migration by regulating G1/S transition key players and adhesion dynamics, primarily via the MEK pathway.","method":"MAP3K8 knockdown/overexpression in ovarian cancer cells; patient-derived xenografts; MEK pathway inhibitor experiments; cell cycle and migration assays","journal":"Nature communications","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — cell line KD/OE with phenotypic readouts plus xenograft model and patient cohort analysis, single lab","pmids":["26456302"],"is_preprint":false},{"year":2015,"finding":"MAP3K8 mediates E2 (estradiol)-stimulated progesterone production in mouse corpus luteum via GPR30 (G protein-coupled receptor 30), stimulating ERK phosphorylation downstream. siRNA knockdown of MAP3K8 or pharmacological MAP3K8 inhibition significantly blocks progesterone synthesis and neutralizes E2's enhancing effect on progesterone production.","method":"siRNA knockdown; MAP3K8 inhibitor; hormone assays; ERK phosphorylation; co-expression with GPR30","journal":"Molecular endocrinology (Baltimore, Md.)","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — siRNA plus pharmacological inhibitor, ERK readout, single lab","pmids":["25763610"],"is_preprint":false},{"year":2018,"finding":"The TPL-2/NF-κB1 p105/ABIN-2 complex has a distinct substrate specificity profile from the isolated TPL-2 kinase domain, determined by positional scanning peptide library. The complex also shows significantly altered sensitivities to existing ATP-competitive TPL-2 inhibitors compared to the isolated kinase domain, suggesting allosteric inhibitor opportunities.","method":"Positional scanning peptide library; high-throughput mass spectrometry kinase activity assay; comparison of complex vs. isolated kinase domain with multiple inhibitors","journal":"The Biochemical journal","confidence":"Medium","confidence_rationale":"Tier 1 / Moderate — in vitro biochemical assay with purified complex, single lab, novel substrate specificity determination","pmids":["29229763"],"is_preprint":false}],"current_model":"MAP3K8/TPL-2 is a serine/threonine MAP kinase kinase kinase that, in its basal state, is held in an inactive ternary complex with NF-κB1 p105 (which blocks MEK access and provides stability) and ABIN-2 (which further stabilizes the complex); upon TLR, TNF-R, or IL-1R stimulation, IKK2 phosphorylates both p105 (triggering proteasomal degradation and TPL-2 release) and TPL-2 Ser400, which cooperates with TPL-2 Ser443 autophosphorylation to recruit 14-3-3, thereby stimulating TPL-2 to phosphorylate and activate MKK1/2 (leading to ERK1/2) and MKK3/6 (leading to p38α); active TPL-2 also promotes phagosome acidification via DMXL1 phosphorylation and V-ATPase assembly, suppresses IFN-β through an ERK1/2-TCF-FOS axis, and regulates Cox-2/PGE2 production, NF-κB-dependent transcription, and NFAT/IL-2 in T cells, while its oncogenic C-terminal truncation removes the autoinhibitory tail, S400, and 14-3-3 dependence, rendering the kinase constitutively active."},"narrative":{"mechanistic_narrative":"MAP3K8 (TPL-2/Cot) is a serine/threonine MAP kinase kinase kinase that couples innate immune receptor engagement to MAPK output, directly phosphorylating and activating the MAP kinase kinases that drive ERK1/2 and JNK/SAPK signaling [PMID:8631303]. In resting cells the kinase is held inactive within a stoichiometric complex: NF-κB1 p105 binds TPL-2 through dual contacts—its 497–534 region engaging the TPL-2 C-terminus and its death domain engaging the kinase domain—to suppress MEK kinase activity and stabilize the protein, while ABIN-2 provides additional stability such that its loss collapses steady-state TPL-2 levels [PMID:9950430, PMID:12832462, PMID:15169888]. Activating signals from TLRs, TNF, CD40, and IL-1R relieve this restraint through the IKK complex, which phosphorylates p105 PEST serines to trigger proteasomal degradation and TPL-2 release, and additionally phosphorylates TPL-2 Ser400; S400 phosphorylation cooperates with Ser443 autophosphorylation to recruit 14-3-3, which is required to stimulate MEK kinase activity and downstream ERK1/2 activation [PMID:15485931, PMID:17709378, PMID:22988300, PMID:24912162, PMID:22733995]. Beyond the MKK1/2-ERK axis, TPL-2 is the MAP3K for the MKK3/6-p38α module downstream of TLR4 and TNF [PMID:27402796]. These pathways shape macrophage and dendritic cell function: TPL-2/ERK signaling suppresses IFN-β and IL-12 via an ERK1/2-TCF-FOS transcriptional axis [PMID:19667062, PMID:35082159], controls Cox-2/PGE2 production in lung macrophages [PMID:33443087], and, through a MAP-kinase-independent route, drives DMXL1 phosphorylation and V-ATPase assembly to acidify phagosomes for bacterial killing [PMID:33881780]. TPL-2 stability is further constrained by BCL-3-promoted nuclear shuttling and proteasomal turnover [PMID:31772019]. Oncogenic activation arises from C-terminal truncation, which removes the autoinhibitory tail, S400, and 14-3-3 dependence to render the kinase constitutively active [PMID:9087424, PMID:24912162]; such truncating MAP3K8 rearrangements drive constitutive MEK-ERK signaling and confer MEK/ERK-inhibitor sensitivity in spitzoid melanoma and other tumors [PMID:30833747, PMID:31186280].","teleology":[{"year":1994,"claim":"Before its biochemical activity was known, genetic epistasis placed Tpl-2 within mitogenic Ras/Raf signaling, establishing it as a transducer of proliferative MAPK signals.","evidence":"Dominant-negative Ras/Raf-1 co-transfection epistasis in cell lines","pmids":["7937886"],"confidence":"Medium","gaps":["Direct kinase substrates not yet defined","Physiological activating receptor not identified","Relies on overexpressed dominant-negative constructs"]},{"year":1996,"claim":"Established the core molecular activity—that TPL-2 is a MAP3K that directly phosphorylates the MAP kinase kinases MEK-1 and SEK-1 to activate both ERK and JNK/SAPK cascades.","evidence":"In vitro kinase assay with immunoprecipitated TPL-2 and recombinant GST-MEK-1/SEK-1; transfection in COS-1 and Jurkat cells","pmids":["8631303"],"confidence":"High","gaps":["Regulation of basal activity unaddressed","Physiological versus overexpression substrate preference unclear"]},{"year":1997,"claim":"Revealed intrinsic autoinhibition—the C-terminal tail folds back on the kinase domain to suppress activity, defining the molecular basis later exploited by oncogenic truncation.","evidence":"In vitro kinase comparison of wild-type vs truncated Tpl-2; GST pulldown of tail with kinase domain in Sf9 cells; transgenic mice","pmids":["9087424"],"confidence":"High","gaps":["Trans-acting regulators of the tail not yet known","Did not identify the phosphorylation events controlling the tail"]},{"year":1999,"claim":"Connected TPL-2 to NF-κB by showing it phosphorylates p105 to promote its degradation, linking the kinase to two transcriptional outputs.","evidence":"Co-IP, wild-type vs kinase-inactive TPL-2, p105 phosphorylation/degradation assays","pmids":["9950430"],"confidence":"High","gaps":["Whether p105 also regulates TPL-2 reciprocally not yet shown","Kinase responsible for p105 phosphorylation in vivo unresolved"]},{"year":2003,"claim":"Defined p105 as a bidirectional partner that both inhibits TPL-2 MEK kinase activity through dual-domain binding and stabilizes the protein, explaining the inactive resting state and oncogene insensitivity.","evidence":"In vitro kinase assay, domain-mapping Co-IP, C-terminal deletion mutants","pmids":["12832462"],"confidence":"High","gaps":["Did not establish the signal that disrupts the inhibitory interaction"]},{"year":2004,"claim":"Established the activation switch: IKK-driven p105 proteolysis releases TPL-2, and the freed pool carries the MEK kinase activity, while ABIN-2 was identified as a third stabilizing subunit.","evidence":"Co-IP, IKK blockade, reconstitution of NF-κB1-deficient macrophages with IKK-site mutant p105, RNAi/pulse-chase for ABIN-2","pmids":["15485931","15169888"],"confidence":"High","gaps":["Whether release alone is sufficient for full activation unresolved","Direct phosphorylation of TPL-2 itself not yet demonstrated"]},{"year":2007,"claim":"Showed that release from p105 is necessary but not sufficient—LPS-induced Ser400 phosphorylation is a second obligatory activation step, and its loss in truncations links to oncogenesis.","evidence":"S400A mutagenesis, retroviral reconstitution in Nfkb1-/- and Map3k8-/- macrophages, in vitro MEK kinase assay","pmids":["17709378"],"confidence":"High","gaps":["Kinase phosphorylating S400 not identified","Downstream consequence of S400-P not mechanistically explained"]},{"year":2012,"claim":"Identified IKK2 as the S400 kinase and showed IKK controls both activation steps (p105 proteolysis and S400 phosphorylation) across multiple TLR ligands and TNF, unifying the upstream input.","evidence":"In vitro kinase assay with recombinant IKK2; SSAA p105 knock-in mouse; multiple TLR ligands; IKK2 inhibition","pmids":["22988300","22733995"],"confidence":"High","gaps":["How S400 phosphorylation mechanistically stimulates catalysis not yet resolved"]},{"year":2014,"claim":"Resolved the activation mechanism: IKK-phosphorylated S400 plus S443 autophosphorylation recruit 14-3-3, which is required to stimulate MEK kinase activity, and truncation bypasses this 14-3-3 dependence.","evidence":"Co-IP of TPL-2/14-3-3, S400/S443 mutagenesis, in vitro MEK-1 kinase assay, reconstitution in Map3k8-/- macrophages","pmids":["24912162"],"confidence":"High","gaps":["Structural basis of 14-3-3-induced activation not determined"]},{"year":2016,"claim":"Broadened TPL-2 output beyond ERK by demonstrating it is the MAP3K for the MKK3/6-p38α axis downstream of TLR4 and TNF.","evidence":"Quantitative phosphoproteomics in Map3k8-D270A kinase-dead vs wild-type macrophages","pmids":["27402796"],"confidence":"High","gaps":["Why MKK4 is not a substrate unexplained","Determinants of MKK3/6 versus MKK1/2 selectivity unknown"]},{"year":null,"claim":"Multiple TPL-2 functions reported in non-macrophage and tumor contexts (NFAT/IL-2 in T cells, p53/PP2A regulation, caspase-9/Tvl-1 apoptosis, GPR30-driven progesterone, ovarian and HTLV-1 contexts) remain mechanistically siloed and not integrated into a unified signaling model.","evidence":"","pmids":[],"confidence":"Medium","gaps":["Whether these context-specific roles share the p105/14-3-3 activation logic is untested","Direct substrates in T cells and reproductive tissue not biochemically defined","Relationship between MAP-kinase-dependent and -independent (DMXL1/V-ATPase) outputs not fully mapped"]}],"mechanism_profile":{"molecular_activity":[{"term_id":"GO:0140096","term_label":"catalytic activity, acting on a protein","supporting_discovery_ids":[0,7,8,11,19]},{"term_id":"GO:0016740","term_label":"transferase activity","supporting_discovery_ids":[0,9,11]},{"term_id":"GO:0140657","term_label":"ATP-dependent activity","supporting_discovery_ids":[29]}],"localization":[{"term_id":"GO:0005829","term_label":"cytosol","supporting_discovery_ids":[5,18]},{"term_id":"GO:0005634","term_label":"nucleus","supporting_discovery_ids":[18]}],"pathway":[{"term_id":"R-HSA-168256","term_label":"Immune System","supporting_discovery_ids":[10,11,15,22,19]},{"term_id":"R-HSA-162582","term_label":"Signal Transduction","supporting_discovery_ids":[0,8,9,11]},{"term_id":"R-HSA-1643685","term_label":"Disease","supporting_discovery_ids":[25,26,27]}],"complexes":["TPL-2/NF-κB1 p105/ABIN-2 ternary complex"],"partners":["NFKB1","TNIP2","YWHA (14-3-3)","CHUK/IKBKB (IKK)","TRAF2","BCL3","TP53","DMXL1"],"other_free_text":[]}},"prefetch_data":{"uniprot":{"accession":"P41279","full_name":"Mitogen-activated protein kinase kinase kinase 8","aliases":["Cancer Osaka thyroid oncogene","Proto-oncogene c-Cot","Serine/threonine-protein kinase cot","Tumor progression locus 2","TPL-2"],"length_aa":467,"mass_kda":52.9,"function":"Required for lipopolysaccharide (LPS)-induced, TLR4-mediated activation of the MAPK/ERK pathway in macrophages, thus being critical for production of the pro-inflammatory cytokine TNF (TNF) during immune responses. Involved in the regulation of T-helper cell differentiation and IFNG expression in T-cells. Involved in mediating host resistance to bacterial infection through negative regulation of type I interferon (IFN) production. In vitro, activates MAPK/ERK pathway in response to IL1 in an IRAK1-independent manner, leading to up-regulation of IL8 and CCL4. Transduces CD40 and TNFRSF1A signals that activate ERK in B-cells and macrophages, and thus may play a role in the regulation of immunoglobulin production. May also play a role in the transduction of TNF signals that activate JNK and NF-kappa-B in some cell types. In adipocytes, activates MAPK/ERK pathway in an IKBKB-dependent manner in response to IL1B and TNF, but not insulin, leading to induction of lipolysis. Plays a role in the cell cycle. 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TNIP2","url":"https://www.omim.org/entry/610669"},{"mim_id":"602539","title":"MITOGEN-ACTIVATED KINASE KINASE KINASE 3; MAP3K3","url":"https://www.omim.org/entry/602539"},{"mim_id":"191195","title":"MITOGEN-ACTIVATED PROTEIN KINASE KINASE KINASE 8; MAP3K8","url":"https://www.omim.org/entry/191195"}],"hpa":{"profiled":true,"resolved_as":"","reliability":"Supported","locations":[{"location":"Cytosol","reliability":"Supported"}],"tissue_specificity":"Tissue enriched","tissue_distribution":"Detected in all","driving_tissues":[{"tissue":"bone 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molecular sciences","url":"https://pubmed.ncbi.nlm.nih.gov/36768307","citation_count":9,"is_preprint":false},{"pmid":"19221002","id":"PMC_19221002","title":"Tpl-2 kinase downregulates the activity of p53 and enhances signaling pathways leading to activation of activator protein 1 induced by EGF.","date":"2009","source":"Carcinogenesis","url":"https://pubmed.ncbi.nlm.nih.gov/19221002","citation_count":9,"is_preprint":false},{"pmid":"39030600","id":"PMC_39030600","title":"MAP3K8 is a potential therapeutic target in airway epithelial inflammation.","date":"2024","source":"Journal of inflammation (London, England)","url":"https://pubmed.ncbi.nlm.nih.gov/39030600","citation_count":7,"is_preprint":false},{"pmid":"36252394","id":"PMC_36252394","title":"Enhanced expression of miR-26a ameliorates lipopolysaccharide-induced endometritis by targeting MAP3K8 to inactivate MAPK signaling pathway.","date":"2022","source":"Journal of reproductive 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proteins; transfection of COS-1 and Jurkat T cells showing ERK-1 and SAP kinase activation\",\n      \"journal\": \"The EMBO journal\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1 / Strong — direct in vitro kinase assay reconstituted with purified proteins, replicated in multiple cell lines\",\n      \"pmids\": [\"8631303\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 1994,\n      \"finding\": \"MAP3K8/Tpl-2-induced MAPK activation is blocked by dominant-negative mutants of Ras and Raf-1, and kinase-deficient Tpl-2 down-regulates mitogenic signals from v-Ha-Ras or v-Raf, placing Tpl-2 in the Ras/Raf-1 signaling complex.\",\n      \"method\": \"Dominant-negative mutant co-transfection epistasis in cell lines\",\n      \"journal\": \"Proceedings of the National Academy of Sciences of the United States of America\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — genetic epistasis with dominant-negative constructs, single lab, two complementary approaches\",\n      \"pmids\": [\"7937886\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 1997,\n      \"finding\": \"C-terminal truncation of Tpl-2 increases catalytic activity ~7-fold and enhances MAPK/SAPK pathway activation 2-3 fold; the C-terminal tail interacts with the truncated kinase domain (GST fusion co-expression in Sf9 cells) and mediates autoinhibitory intramolecular interactions that down-regulate kinase activity.\",\n      \"method\": \"In vitro kinase assay comparing wild-type and truncated Tpl-2; GST pulldown of C-terminal tail with truncated protein in Sf9 cells; transgenic mouse model\",\n      \"journal\": \"Genes & development\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1 / Strong — in vitro kinase assay with mutagenesis, protein interaction confirmed by co-expression pulldown, functional validation in transgenic mice\",\n      \"pmids\": [\"9087424\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 1999,\n      \"finding\": \"TPL-2 forms a complex with the C-terminus of NF-κB1 p105; TPL-2 expression causes phosphorylation and increased degradation of p105 while maintaining p50 production, thereby releasing associated Rel subunits to generate active nuclear NF-κB. Kinase-inactive TPL-2 blocks TNF-α-induced p105 degradation.\",\n      \"method\": \"Co-immunoprecipitation; transfection with wild-type and kinase-inactive TPL-2; p105 phosphorylation and degradation assays\",\n      \"journal\": \"Nature\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — reciprocal Co-IP, kinase-dead mutant rescue, multiple orthogonal methods, published in Nature\",\n      \"pmids\": [\"9950430\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2003,\n      \"finding\": \"NF-κB1 p105 negatively regulates TPL-2 MEK kinase activity through two distinct interactions: the TPL-2 C-terminus binds p105 residues 497–534, while the TPL-2 kinase domain interacts with the p105 death domain. Binding to the p105 death domain inhibits TPL-2 MEK kinase activity in vitro, and both interactions are required for full inhibition in cells. C-terminally truncated oncogenic TPL-2 is insensitive to this inhibition. TPL-2 stability in vivo depends on its high-affinity stoichiometric association with p105.\",\n      \"method\": \"In vitro kinase assay; co-immunoprecipitation mapping of binding domains; cotransfection experiments with C-terminal deletion mutants\",\n      \"journal\": \"Molecular and cellular biology\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1 / Strong — in vitro kinase assay combined with domain-mapping Co-IP and mutagenesis, multiple orthogonal methods\",\n      \"pmids\": [\"12832462\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2004,\n      \"finding\": \"LPS stimulation releases both forms of TPL-2 from the p105 complex, and TPL-2 MEK kinase activity is restricted to the p105-free pool. IKK complex phosphorylation of two serines in the p105 PEST region triggers proteasome-mediated p105 proteolysis, which is essential for TPL-2 release and subsequent activation of MEK and ERK. Expression of a p105 point mutant not susceptible to signal-induced proteolysis impairs LPS-induced TPL-2 activation; wild-type but not mutant p105 reconstitutes LPS-stimulated MEK/ERK signaling in NF-κB1-deficient macrophages.\",\n      \"method\": \"Co-immunoprecipitation; pharmacological IKK blockade; reconstitution in primary NF-κB1-deficient macrophages with wild-type vs. IKK-site mutant p105; proteasome inhibitors\",\n      \"journal\": \"Molecular and cellular biology\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1 / Strong — reconstitution in primary macrophages with site-specific mutants, multiple orthogonal methods, mechanistically definitive\",\n      \"pmids\": [\"15485931\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2004,\n      \"finding\": \"ABIN-2 forms a ternary complex with TPL-2 and NF-κB1 p105. ABIN-2 is required for TPL-2 protein stability: RNAi depletion of ABIN-2 dramatically reduces steady-state TPL-2 protein without affecting TPL-2 mRNA or p105 levels, and ABIN-2 increases TPL-2 half-life. LPS activation of TPL-2 correlates with its release from ABIN-2.\",\n      \"method\": \"Affinity purification identifying ABIN-2 as novel p105-associated protein; co-immunoprecipitation of endogenous proteins in bone marrow-derived macrophages; RNA interference; pulse-chase half-life experiments\",\n      \"journal\": \"Molecular and cellular biology\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — affinity purification, reciprocal Co-IP of endogenous proteins, RNAi with protein stability readout, replicated in primary macrophages\",\n      \"pmids\": [\"15169888\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2007,\n      \"finding\": \"LPS stimulation induces phosphorylation of serine 400 in the TPL-2 C-terminal tail. Mutation of S400 to alanine blocks LPS-stimulated TPL-2 MEK kinase activity and ERK activation independently of p105 release, demonstrating that S400 phosphorylation is a second required regulatory step for TPL-2 activation. C-terminal truncations that remove S400 may contribute to oncogenic activation.\",\n      \"method\": \"Site-directed mutagenesis (S400A); retroviral reconstitution in Nfkb1-/- and Map3k8-/- macrophages; in vitro MEK kinase assay\",\n      \"journal\": \"Molecular and cellular biology\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1 / Strong — in vitro kinase assay with site-directed mutagenesis, reconstitution in two knockout cell backgrounds\",\n      \"pmids\": [\"17709378\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2012,\n      \"finding\": \"IκB kinase 2 (IKK2) directly phosphorylates TPL-2 on serine 400, providing the transphosphorylation signal required for TPL-2 activation of ERK-1/2 independently of p105 regulation. The IKK complex therefore controls both key regulatory steps of TPL-2 activation: p105 proteolysis and TPL-2 S400 phosphorylation.\",\n      \"method\": \"In vitro kinase assay with recombinant IKK2 and TPL-2 substrates; site-directed mutagenesis; pharmacological IKK2 inhibition in macrophages\",\n      \"journal\": \"Molecular and cellular biology\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1 / Strong — in vitro kinase reconstitution with recombinant proteins plus mutagenesis and pharmacological validation\",\n      \"pmids\": [\"22988300\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2014,\n      \"finding\": \"IKK-mediated phosphorylation of TPL-2 S400 cooperates with TPL-2 S443 autophosphorylation to trigger TPL-2 association with 14-3-3 proteins. 14-3-3 binding to the phosphorylated C-terminus stimulates TPL-2 MEK-1 kinase activity and is essential for ERK-1/2 activation and LPS-induced TNF production. C-terminal deletion of TPL-2 renders its kinase activity independent of 14-3-3, contributing to oncogenic transformation.\",\n      \"method\": \"Co-immunoprecipitation of TPL-2 and 14-3-3; site-directed mutagenesis of S400 and S443; in vitro MEK-1 kinase assay; retroviral reconstitution in Map3k8-/- macrophages\",\n      \"journal\": \"Proceedings of the National Academy of Sciences of the United States of America\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1 / Strong — in vitro kinase assay, Co-IP, mutagenesis of two sites, reconstitution in knockout macrophages\",\n      \"pmids\": [\"24912162\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2012,\n      \"finding\": \"IKK-induced proteolysis of NF-κB1 p105 (via IKK phosphorylation of p105 PEST serines) is essential for TPL-2/ERK activation by multiple TLR ligands (LPS, CpG, Pam3CSK, poly(I·C), flagellin, R848) and by TNF. Mutation of the IKK target serines on p105 (SSAA) blocks agonist-induced TPL-2 release from p105 and ERK activation. TPL-2/ERK activation creates a negative feedback loop to suppress IL-12 expression.\",\n      \"method\": \"Knock-in mouse model (Nfkb1-SSAA/SSAA); macrophage stimulation with multiple TLR ligands; ERK phosphorylation assays; gene expression analysis\",\n      \"journal\": \"Molecular and cellular biology\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — physiological knock-in mouse model with multiple TLR ligands tested, mechanistically definitive, multiple orthogonal readouts\",\n      \"pmids\": [\"22733995\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2016,\n      \"finding\": \"TPL-2 catalytic activity is required for phosphorylation of MKK3 and MKK6 activation loops (but not MKK4) downstream of TLR4 and TNF stimulation in macrophages, placing TPL-2 as the MAP3K for the MKK3/6-p38α axis in addition to the MKK1/2-ERK axis. MKK3/6 activation also requires IKK phosphorylation of NF-κB1 p105. TNF activation of p38α is substantially dependent on TPL-2 via MKK3/6.\",\n      \"method\": \"Quantitative mass spectrometry of protein phosphorylation in wild-type vs. Map3k8-D270A/D270A (kinase-dead) macrophages following LPS/TNF/bacterial stimulation\",\n      \"journal\": \"The Biochemical journal\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1 / Strong — quantitative phosphoproteomics with kinase-dead knock-in model, unbiased substrate identification\",\n      \"pmids\": [\"27402796\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 1998,\n      \"finding\": \"TPL-2 activates the NFAT transcription factor and induces IL-2 expression in T-cell lines via convergence of the MAPK and calcineurin/NFAT pathways. NFATp (but not NFATc or NFATx) undergoes nuclear translocation when co-expressed with wild-type Tpl-2. Kinase-dead Tpl-2 K167M inhibits anti-CD3-stimulated NFAT activation in Jurkat cells. TPL-2 also activates NF-κB to cooperate in IL-2 promoter induction.\",\n      \"method\": \"Transfection with dominant-negative signaling molecules; NFAT-driven reporter assays; nuclear translocation assay; specific isoform co-expression\",\n      \"journal\": \"Proceedings of the National Academy of Sciences of the United States of America\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — kinase-dead mutant plus reporter assays and nuclear localization, single lab\",\n      \"pmids\": [\"9520452\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2002,\n      \"finding\": \"TPL-2/Cot interacts with TRAF2 (co-immunoprecipitation and co-localization), functioning downstream of TRAF2, and contributes to LMP1-induced NF-κB signaling. Catalytically inactive TPL-2 suppresses LMP1- and CD40-induced NF-κB activation. TPL-2 modulates both IκBα and p105 functions in this pathway.\",\n      \"method\": \"Co-immunoprecipitation; co-localization; dominant-negative kinase-dead TPL-2 transfection; NF-κB reporter assay\",\n      \"journal\": \"Journal of virology\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — reciprocal Co-IP plus kinase-dead functional assay, single lab\",\n      \"pmids\": [\"11932422\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2005,\n      \"finding\": \"MAP3K8/Tpl-2 is recruited to the CD40 receptor complex through TRAF-binding sites in CD40 (TRAF-dependent association). Catalytically inactive Tpl-2 suppresses CD40-mediated IKK activation and NF-κB induction. Tpl2-/- fibroblasts are deficient in CD40 but not TNF signaling. Tpl-2 functions distal to TRAFs but proximal to the TAK1/TAB1 complex.\",\n      \"method\": \"Co-immunoprecipitation of Tpl-2 with CD40 complex; kinase-dead dominant-negative transfection; Tpl2-/- fibroblast genetic experiments; epistasis with TAK1/TAB1\",\n      \"journal\": \"Biochemical and biophysical research communications\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — Co-IP, knockout fibroblasts, dominant-negative epistasis, single lab\",\n      \"pmids\": [\"15670770\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2009,\n      \"finding\": \"TPL-2 negatively regulates LPS- and CpG-induced IFN-β production in macrophages and myeloid DCs via ERK-dependent induction of c-Fos. In the absence of TPL-2 signaling, IFN-β is increased while IL-10 is decreased. The negative regulation requires protein synthesis and is independent of IL-10.\",\n      \"method\": \"Map3k8-/- macrophages and myeloid DCs; retroviral transduction of ERK-dependent transcription factor c-Fos into TPL-2-deficient cells; cytokine secretion assays\",\n      \"journal\": \"The Journal of experimental medicine\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — knockout primary cells plus reconstitution with downstream effector, multiple TLR ligands tested, mechanistically defined\",\n      \"pmids\": [\"19667062\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2010,\n      \"finding\": \"Arginine availability facilitates TPL-2 activation downstream of TLR4 by preventing dephosphorylation and inactivation of TPL-2 in LPS-stimulated macrophages, thereby enabling ERK1/2 activation and TNF-α production. Arginine starvation impairs LPS-induced ERK1/2 activation in vivo.\",\n      \"method\": \"Arginine depletion/supplementation experiments in cultured macrophages and in mice; ERK1/2 and TPL-2 phosphorylation assays; in vivo arginine supplementation\",\n      \"journal\": \"Science signaling\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — both in vitro and in vivo validation, single lab, mechanistic follow-up limited to phosphorylation assays\",\n      \"pmids\": [\"20716763\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2001,\n      \"finding\": \"Tpl-2 induces apoptosis by promoting assembly of a complex containing caspase-9, the ankyrin repeat protein Tvl-1, and procaspase-3, leading to caspase-9-dependent caspase-3 activation. Co-expression with Tvl-1 enhances this effect; procaspase-3 conditionally associates with Tvl-1 in response to Tpl-2 apoptotic signals.\",\n      \"method\": \"Co-immunoprecipitation of complex components; caspase activity assays; co-transfection in non-transformed cells\",\n      \"journal\": \"Journal of cellular physiology\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — Co-IP of complex plus functional caspase assay, single lab\",\n      \"pmids\": [\"11267997\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2019,\n      \"finding\": \"BCL-3, a nuclear IκB protein, promotes TPL-2 degradation by increasing TPL-2 nuclear localization. TPL-2 is a nucleocytoplasmic shuttling protein, and the nucleus is the primary site for its proteasomal degradation after TLR stimulation. BCL-3 interacts with TPL-2 and promotes nuclear retention, thereby limiting MAPK activity. Bcl3-/- macrophages have increased TPL-2 stability, elevated MAPK activity, and lower TLR stimulation threshold for cytokine production.\",\n      \"method\": \"Bcl3-/- macrophages; co-immunoprecipitation of BCL-3 and TPL-2; subcellular fractionation; nuclear localization imaging; proteasome inhibitor experiments\",\n      \"journal\": \"Proceedings of the National Academy of Sciences of the United States of America\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — knockout primary cells, Co-IP, subcellular fractionation with functional consequence, multiple orthogonal methods\",\n      \"pmids\": [\"31772019\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2021,\n      \"finding\": \"TPL-2 catalytic activity induces phagosome acidification and proteolysis in macrophages through a MAP kinase-independent mechanism. TPL-2 stimulates phosphorylation of DMXL1 (a V-ATPase regulator), promoting V-ATPase assembly on phagosomes. Blocking TPL-2 catalytic activity reduces V-ATPase proton pump subunit abundance on phagosomes and impairs killing of S. aureus and C. rodentium.\",\n      \"method\": \"Map3k8-D270A/D270A kinase-dead macrophages; quantitative phagosome proteomics; latex bead phagosome assay; bacterial killing assay; V-ATPase assembly analysis; DMXL1 phosphorylation\",\n      \"journal\": \"The EMBO journal\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1 / Strong — quantitative proteomics with kinase-dead mutant, novel substrate (DMXL1) identification, functional bacterial killing assay in both mouse and human macrophages\",\n      \"pmids\": [\"33881780\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2009,\n      \"finding\": \"Tpl-2 wild-type protein interacts with p53 in vitro and in cells. Overexpression of Tpl-2 inhibits EGF-induced p53 phosphorylation (Ser15) by upregulating protein phosphatase 2A activity. Mutation S413A in Tpl-2 abrogates suppression of p53 activity and EGF-induced c-fos promoter/AP-1 transactivation.\",\n      \"method\": \"Co-immunoprecipitation of Tpl-2 and p53 in vitro and ex vivo; site-directed mutagenesis (S413A); p53 phosphorylation and transcriptional activity assays\",\n      \"journal\": \"Carcinogenesis\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — Co-IP plus mutagenesis, single lab, mechanistic follow-up via PP2A\",\n      \"pmids\": [\"19221002\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2022,\n      \"finding\": \"TPL-2 (MAP3K8) activation promotes Th1-like differentiation and constitutively activates MEK-ERK signaling in HTLV-1-infected T cells. HTLV-1 Tax, Fosl2, and c-Jun collaboratively induce chromatin remodeling at the MAP3K8 enhancer locus, driving MAP3K8 overexpression. MEK inhibitors suppress the MAP3K8-MEK signaling cascade and mitigate inflammatory pathogenesis ex vivo.\",\n      \"method\": \"Chromatin accessibility profiling (ATAC-seq); transcriptomic analysis; chromatin immunoprecipitation; MEK inhibitor treatment in ex vivo culture; overexpression of Tax, Fosl2, c-Jun\",\n      \"journal\": \"Nature communications\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — chromatin profiling plus functional inhibitor validation, single lab, novel mechanism for MAP3K8 transcriptional regulation\",\n      \"pmids\": [\"41213906\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2022,\n      \"finding\": \"TPL-2 inhibition of IFN-β in TLR4-stimulated macrophages is mediated via an ERK1/2-TCF-FOS axis. TPL-2 activates ERK1/2, which phosphorylates ELK1 (a ternary complex factor) and induces TCF target genes including FOS. TCFs mediate approximately half of the transcriptional output of TPL-2 signaling, partially via secondary transcription factors. Loss of FOS recapitulates a significant fraction of TPL-2 transcriptional regulation.\",\n      \"method\": \"Transcriptomic comparison of wild-type vs. Map3k8-D270A/D270A macrophages; TCF-deficient macrophages; Fos-/- macrophages; bioinformatics motif analysis; ELK1 phosphorylation assay\",\n      \"journal\": \"Journal of immunology (Baltimore, Md. : 1950)\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — kinase-dead knock-in plus multiple transcription factor knockouts, genome-wide transcriptomics, mechanistic pathway delineation\",\n      \"pmids\": [\"35082159\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2020,\n      \"finding\": \"MAP3K8 regulates Cox-2 expression and PGE2 production in macrophages in the lung. Map3k8 deficiency in mice reduces Cox-2 expression and PGE2 levels; macrophage-specific deletion of Map3k8 is sufficient to exacerbate pulmonary fibrosis. Exogenous PGE2 administration rescues the exacerbated fibrotic phenotype of Map3k8-/- mice.\",\n      \"method\": \"Conditional macrophage-specific Map3k8 knockout (LysM-Cre); bone marrow transplantation; bleomycin fibrosis model; Cox-2 and PGE2 measurements; PGE2 rescue experiment\",\n      \"journal\": \"Journal of immunology (Baltimore, Md. : 1950)\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — cell-type-specific conditional knockout plus bone marrow transfer plus pharmacological rescue, multiple orthogonal approaches\",\n      \"pmids\": [\"33443087\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2018,\n      \"finding\": \"Hypoxia increases MAP3K8 expression via HIF-1 (hypoxia-induced factor) transcriptional activation, upstream of the p38 MAPK pathway in monocyte-derived dendritic cells. MAP3K8 knockdown or pharmacological inhibition reduces hypoxia-potentiated TNF-α secretion and p38 MAPK phosphorylation.\",\n      \"method\": \"siRNA knockdown of MAP3K8 in human moDCs; MAP3K8 inhibitor; TNF-α ELISA; p38 phosphorylation assay; HIF-ChIP or HIF-target analysis\",\n      \"journal\": \"Bioscience reports\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — siRNA knockdown plus inhibitor, single lab, functional readout\",\n      \"pmids\": [\"30463908\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2019,\n      \"finding\": \"MAP3K8 fusions in spitzoid melanoma invariably encode the intact kinase domain but lack the autoinhibitory C-terminal exon (exon 1-8 fusions), resulting in constitutively active kinase. These truncating rearrangements activate MEK signaling and confer sensitivity to MEK inhibition.\",\n      \"method\": \"RNA sequencing identification of fusion transcripts; clinical MEK inhibitor treatment with tumor response; FISH break-apart assay\",\n      \"journal\": \"Nature medicine\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — RNA-seq structural characterization in large patient cohort, clinical MEK inhibitor response, mechanistic inference supported by known C-terminal autoinhibition\",\n      \"pmids\": [\"30833747\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2019,\n      \"finding\": \"Truncating MAP3K8 rearrangements in driver-negative melanoma cell lines result in increased levels of truncated, constitutively active MAP3K8 protein, oncogenic ERK dependency, resistance to BRAF inhibition, and sensitivity to MEK or ERK1/2 inhibition.\",\n      \"method\": \"Endogenous MAP3K8 rearranged melanoma cell lines; FISH validation; western blot of truncated protein; MEK/ERK inhibitor sensitivity assays; BRAF inhibitor resistance assay\",\n      \"journal\": \"Molecular cancer research : MCR\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — endogenous rearrangements in cell lines with biochemical and pharmacological characterization, single lab\",\n      \"pmids\": [\"31186280\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2015,\n      \"finding\": \"MAP3K8 overexpression in high-grade serous ovarian carcinoma cells controls cancer cell proliferation and migration by regulating G1/S transition key players and adhesion dynamics, primarily via the MEK pathway.\",\n      \"method\": \"MAP3K8 knockdown/overexpression in ovarian cancer cells; patient-derived xenografts; MEK pathway inhibitor experiments; cell cycle and migration assays\",\n      \"journal\": \"Nature communications\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — cell line KD/OE with phenotypic readouts plus xenograft model and patient cohort analysis, single lab\",\n      \"pmids\": [\"26456302\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2015,\n      \"finding\": \"MAP3K8 mediates E2 (estradiol)-stimulated progesterone production in mouse corpus luteum via GPR30 (G protein-coupled receptor 30), stimulating ERK phosphorylation downstream. siRNA knockdown of MAP3K8 or pharmacological MAP3K8 inhibition significantly blocks progesterone synthesis and neutralizes E2's enhancing effect on progesterone production.\",\n      \"method\": \"siRNA knockdown; MAP3K8 inhibitor; hormone assays; ERK phosphorylation; co-expression with GPR30\",\n      \"journal\": \"Molecular endocrinology (Baltimore, Md.)\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — siRNA plus pharmacological inhibitor, ERK readout, single lab\",\n      \"pmids\": [\"25763610\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2018,\n      \"finding\": \"The TPL-2/NF-κB1 p105/ABIN-2 complex has a distinct substrate specificity profile from the isolated TPL-2 kinase domain, determined by positional scanning peptide library. The complex also shows significantly altered sensitivities to existing ATP-competitive TPL-2 inhibitors compared to the isolated kinase domain, suggesting allosteric inhibitor opportunities.\",\n      \"method\": \"Positional scanning peptide library; high-throughput mass spectrometry kinase activity assay; comparison of complex vs. isolated kinase domain with multiple inhibitors\",\n      \"journal\": \"The Biochemical journal\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 1 / Moderate — in vitro biochemical assay with purified complex, single lab, novel substrate specificity determination\",\n      \"pmids\": [\"29229763\"],\n      \"is_preprint\": false\n    }\n  ],\n  \"current_model\": \"MAP3K8/TPL-2 is a serine/threonine MAP kinase kinase kinase that, in its basal state, is held in an inactive ternary complex with NF-κB1 p105 (which blocks MEK access and provides stability) and ABIN-2 (which further stabilizes the complex); upon TLR, TNF-R, or IL-1R stimulation, IKK2 phosphorylates both p105 (triggering proteasomal degradation and TPL-2 release) and TPL-2 Ser400, which cooperates with TPL-2 Ser443 autophosphorylation to recruit 14-3-3, thereby stimulating TPL-2 to phosphorylate and activate MKK1/2 (leading to ERK1/2) and MKK3/6 (leading to p38α); active TPL-2 also promotes phagosome acidification via DMXL1 phosphorylation and V-ATPase assembly, suppresses IFN-β through an ERK1/2-TCF-FOS axis, and regulates Cox-2/PGE2 production, NF-κB-dependent transcription, and NFAT/IL-2 in T cells, while its oncogenic C-terminal truncation removes the autoinhibitory tail, S400, and 14-3-3 dependence, rendering the kinase constitutively active.\"\n}\n```","stage2_raw":"{\n  \"mechanistic_narrative\": \"MAP3K8 (TPL-2/Cot) is a serine/threonine MAP kinase kinase kinase that couples innate immune receptor engagement to MAPK output, directly phosphorylating and activating the MAP kinase kinases that drive ERK1/2 and JNK/SAPK signaling [#0]. In resting cells the kinase is held inactive within a stoichiometric complex: NF-\\u03baB1 p105 binds TPL-2 through dual contacts\\u2014its 497\\u2013534 region engaging the TPL-2 C-terminus and its death domain engaging the kinase domain\\u2014to suppress MEK kinase activity and stabilize the protein, while ABIN-2 provides additional stability such that its loss collapses steady-state TPL-2 levels [#3, #4, #6]. Activating signals from TLRs, TNF, CD40, and IL-1R relieve this restraint through the IKK complex, which phosphorylates p105 PEST serines to trigger proteasomal degradation and TPL-2 release, and additionally phosphorylates TPL-2 Ser400; S400 phosphorylation cooperates with Ser443 autophosphorylation to recruit 14-3-3, which is required to stimulate MEK kinase activity and downstream ERK1/2 activation [#5, #7, #8, #9, #10]. Beyond the MKK1/2-ERK axis, TPL-2 is the MAP3K for the MKK3/6-p38\\u03b1 module downstream of TLR4 and TNF [#11]. These pathways shape macrophage and dendritic cell function: TPL-2/ERK signaling suppresses IFN-\\u03b2 and IL-12 via an ERK1/2-TCF-FOS transcriptional axis [#15, #22], controls Cox-2/PGE2 production in lung macrophages [#23], and, through a MAP-kinase-independent route, drives DMXL1 phosphorylation and V-ATPase assembly to acidify phagosomes for bacterial killing [#19]. TPL-2 stability is further constrained by BCL-3-promoted nuclear shuttling and proteasomal turnover [#18]. Oncogenic activation arises from C-terminal truncation, which removes the autoinhibitory tail, S400, and 14-3-3 dependence to render the kinase constitutively active [#2, #9]; such truncating MAP3K8 rearrangements drive constitutive MEK-ERK signaling and confer MEK/ERK-inhibitor sensitivity in spitzoid melanoma and other tumors [#25, #26].\",\n  \"teleology\": [\n    {\n      \"year\": 1994,\n      \"claim\": \"Before its biochemical activity was known, genetic epistasis placed Tpl-2 within mitogenic Ras/Raf signaling, establishing it as a transducer of proliferative MAPK signals.\",\n      \"evidence\": \"Dominant-negative Ras/Raf-1 co-transfection epistasis in cell lines\",\n      \"pmids\": [\"7937886\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Direct kinase substrates not yet defined\", \"Physiological activating receptor not identified\", \"Relies on overexpressed dominant-negative constructs\"]\n    },\n    {\n      \"year\": 1996,\n      \"claim\": \"Established the core molecular activity\\u2014that TPL-2 is a MAP3K that directly phosphorylates the MAP kinase kinases MEK-1 and SEK-1 to activate both ERK and JNK/SAPK cascades.\",\n      \"evidence\": \"In vitro kinase assay with immunoprecipitated TPL-2 and recombinant GST-MEK-1/SEK-1; transfection in COS-1 and Jurkat cells\",\n      \"pmids\": [\"8631303\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Regulation of basal activity unaddressed\", \"Physiological versus overexpression substrate preference unclear\"]\n    },\n    {\n      \"year\": 1997,\n      \"claim\": \"Revealed intrinsic autoinhibition\\u2014the C-terminal tail folds back on the kinase domain to suppress activity, defining the molecular basis later exploited by oncogenic truncation.\",\n      \"evidence\": \"In vitro kinase comparison of wild-type vs truncated Tpl-2; GST pulldown of tail with kinase domain in Sf9 cells; transgenic mice\",\n      \"pmids\": [\"9087424\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Trans-acting regulators of the tail not yet known\", \"Did not identify the phosphorylation events controlling the tail\"]\n    },\n    {\n      \"year\": 1999,\n      \"claim\": \"Connected TPL-2 to NF-\\u03baB by showing it phosphorylates p105 to promote its degradation, linking the kinase to two transcriptional outputs.\",\n      \"evidence\": \"Co-IP, wild-type vs kinase-inactive TPL-2, p105 phosphorylation/degradation assays\",\n      \"pmids\": [\"9950430\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Whether p105 also regulates TPL-2 reciprocally not yet shown\", \"Kinase responsible for p105 phosphorylation in vivo unresolved\"]\n    },\n    {\n      \"year\": 2003,\n      \"claim\": \"Defined p105 as a bidirectional partner that both inhibits TPL-2 MEK kinase activity through dual-domain binding and stabilizes the protein, explaining the inactive resting state and oncogene insensitivity.\",\n      \"evidence\": \"In vitro kinase assay, domain-mapping Co-IP, C-terminal deletion mutants\",\n      \"pmids\": [\"12832462\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Did not establish the signal that disrupts the inhibitory interaction\"]\n    },\n    {\n      \"year\": 2004,\n      \"claim\": \"Established the activation switch: IKK-driven p105 proteolysis releases TPL-2, and the freed pool carries the MEK kinase activity, while ABIN-2 was identified as a third stabilizing subunit.\",\n      \"evidence\": \"Co-IP, IKK blockade, reconstitution of NF-\\u03baB1-deficient macrophages with IKK-site mutant p105, RNAi/pulse-chase for ABIN-2\",\n      \"pmids\": [\"15485931\", \"15169888\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Whether release alone is sufficient for full activation unresolved\", \"Direct phosphorylation of TPL-2 itself not yet demonstrated\"]\n    },\n    {\n      \"year\": 2007,\n      \"claim\": \"Showed that release from p105 is necessary but not sufficient\\u2014LPS-induced Ser400 phosphorylation is a second obligatory activation step, and its loss in truncations links to oncogenesis.\",\n      \"evidence\": \"S400A mutagenesis, retroviral reconstitution in Nfkb1-/- and Map3k8-/- macrophages, in vitro MEK kinase assay\",\n      \"pmids\": [\"17709378\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Kinase phosphorylating S400 not identified\", \"Downstream consequence of S400-P not mechanistically explained\"]\n    },\n    {\n      \"year\": 2012,\n      \"claim\": \"Identified IKK2 as the S400 kinase and showed IKK controls both activation steps (p105 proteolysis and S400 phosphorylation) across multiple TLR ligands and TNF, unifying the upstream input.\",\n      \"evidence\": \"In vitro kinase assay with recombinant IKK2; SSAA p105 knock-in mouse; multiple TLR ligands; IKK2 inhibition\",\n      \"pmids\": [\"22988300\", \"22733995\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"How S400 phosphorylation mechanistically stimulates catalysis not yet resolved\"]\n    },\n    {\n      \"year\": 2014,\n      \"claim\": \"Resolved the activation mechanism: IKK-phosphorylated S400 plus S443 autophosphorylation recruit 14-3-3, which is required to stimulate MEK kinase activity, and truncation bypasses this 14-3-3 dependence.\",\n      \"evidence\": \"Co-IP of TPL-2/14-3-3, S400/S443 mutagenesis, in vitro MEK-1 kinase assay, reconstitution in Map3k8-/- macrophages\",\n      \"pmids\": [\"24912162\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Structural basis of 14-3-3-induced activation not determined\"]\n    },\n    {\n      \"year\": 2016,\n      \"claim\": \"Broadened TPL-2 output beyond ERK by demonstrating it is the MAP3K for the MKK3/6-p38\\u03b1 axis downstream of TLR4 and TNF.\",\n      \"evidence\": \"Quantitative phosphoproteomics in Map3k8-D270A kinase-dead vs wild-type macrophages\",\n      \"pmids\": [\"27402796\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Why MKK4 is not a substrate unexplained\", \"Determinants of MKK3/6 versus MKK1/2 selectivity unknown\"]\n    },\n    {\n      \"year\": null,\n      \"claim\": \"Multiple TPL-2 functions reported in non-macrophage and tumor contexts (NFAT/IL-2 in T cells, p53/PP2A regulation, caspase-9/Tvl-1 apoptosis, GPR30-driven progesterone, ovarian and HTLV-1 contexts) remain mechanistically siloed and not integrated into a unified signaling model.\",\n      \"evidence\": \"\",\n      \"pmids\": [],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Whether these context-specific roles share the p105/14-3-3 activation logic is untested\", \"Direct substrates in T cells and reproductive tissue not biochemically defined\", \"Relationship between MAP-kinase-dependent and -independent (DMXL1/V-ATPase) outputs not fully mapped\"]\n    }\n  ],\n  \"mechanism_profile\": {\n    \"molecular_activity\": [\n      {\"term_id\": \"GO:0140096\", \"supporting_discovery_ids\": [0, 7, 8, 11, 19]},\n      {\"term_id\": \"GO:0016740\", \"supporting_discovery_ids\": [0, 9, 11]},\n      {\"term_id\": \"GO:0140657\", \"supporting_discovery_ids\": [29]}\n    ],\n    \"localization\": [\n      {\"term_id\": \"GO:0005829\", \"supporting_discovery_ids\": [5, 18]},\n      {\"term_id\": \"GO:0005634\", \"supporting_discovery_ids\": [18]}\n    ],\n    \"pathway\": [\n      {\"term_id\": \"R-HSA-168256\", \"supporting_discovery_ids\": [10, 11, 15, 22, 19]},\n      {\"term_id\": \"R-HSA-162582\", \"supporting_discovery_ids\": [0, 8, 9, 11]},\n      {\"term_id\": \"R-HSA-1643685\", \"supporting_discovery_ids\": [25, 26, 27]}\n    ],\n    \"complexes\": [\"TPL-2/NF-\\u03baB1 p105/ABIN-2 ternary complex\"],\n    \"partners\": [\"NFKB1\", \"TNIP2\", \"YWHA (14-3-3)\", \"CHUK/IKBKB (IKK)\", \"TRAF2\", \"BCL3\", \"TP53\", \"DMXL1\"],\n    \"other_free_text\": []\n  }\n}","audit_flag":null,"evaluation":{"pairwise":"win","faith_supported":7,"faith_total":7,"faith_pct":100.0}}