| 1994 |
MEKK1 (MAP3K1) activates the JNK pathway downstream of Ras but does not activate ERK unless overexpressed, demonstrating two distinct Ras-dependent MAPK cascades: Raf-1→ERK and MEKK→JNK. |
Dominant negative and overexpression constructs in mammalian cells, kinase assays |
Science |
High |
7992057
|
| 1994 |
MEKK1 activates the stress-activated protein kinase (SAPK/JNK) pathway by phosphorylating its activator SEK1, which in turn phosphorylates and activates SAPK. |
Inducible MEKK1 expression in NIH3T3 cells, in vitro kinase assay with SEK1 as substrate |
Nature |
High |
7997270
|
| 1995 |
A constitutively active catalytic domain fragment of MEKK1 (MEKK-C) directly phosphorylates MEK1 at S218 and S222 in vitro; MEKK1 also interacts with MEK1 in the yeast two-hybrid system and activates MEK1/2 in mammalian cells, but does not efficiently activate ERK2 compared to EGF stimulation. |
In vitro kinase assay with bacterially expressed MEKK-C, yeast two-hybrid, transfection in mammalian cells |
Proceedings of the National Academy of Sciences of the United States of America |
High |
7624324
|
| 1997 |
MEKK1 induces site-specific phosphorylation of IκBα in vivo and directly activates the IκBα kinase complex in vitro, placing MEKK1 as a critical component of both the c-Jun and NF-κB stress response pathways. |
In vitro IκBα kinase activation assay, in vivo phosphorylation assay |
Cell |
High |
9008162
|
| 1997 |
Caspase cleavage of MEKK1 at a DEVD motif is required for its kinase activation during anoikis; the cleavage product stimulates apoptosis, and a cleavage-resistant MEKK1 mutant partially protects cells from anoikis, establishing a positive feedback loop between caspases and MEKK1. |
Cleavage-resistant and kinase-inactive MEKK1 mutants, caspase inhibitors, cell death assays |
Cell |
High |
9244305
|
| 1998 |
MEKK1 activates both IKK-α and IKK-β in vivo; IKK-α is present in the MEKK1-inducible high molecular weight IκBα kinase complex and MEKK1 treatment induces phosphorylation of IKK-α in vitro. |
In vitro phosphorylation assays, co-immunoprecipitation, transfection in mammalian cells |
Proceedings of the National Academy of Sciences of the United States of America |
High |
9689078
|
| 1998 |
HTLV-I Tax protein binds to the amino terminus of MEKK1, stimulates MEKK1 kinase activity, and increases IKKβ-mediated phosphorylation of IκBα, leading to NF-κB activation. |
Co-immunoprecipitation, in vitro kinase assay, dominant-negative mutant studies, transfection |
Cell |
High |
9630230
|
| 1998 |
Caspase-3 (CPP32) cleaves MEKK1 after residue D68 both in vivo and in vitro during Fas-induced apoptosis; this cleavage redistributes MEKK1 from a Triton-insoluble (particulate) compartment to a Triton-soluble (cytoplasmic) compartment and is required for MEKK1 and SAPK activation during apoptosis but not during rapid stress responses. |
Sequencing of cleavage products, immunofluorescence, subcellular fractionation, viral and chemical caspase inhibitors |
Proceedings of the National Academy of Sciences of the United States of America |
High |
9576928
|
| 1999 |
MEKK1 interacts directly with α-actinin via residues 221–559 of its N-terminal regulatory domain, and both endogenous and overexpressed MEKK1 co-localize with α-actinin along actin stress fibers and at focal adhesions; kinase activity is not required for this localization. |
Yeast two-hybrid screen, co-immunoprecipitation, in vitro binding with purified α-actinin, immunofluorescence colocalization |
Cell motility and the cytoskeleton |
High |
10401575
|
| 1999 |
MEKK1 is required for JNK activation in response to microtubule disruption (taxol) but not actin fiber disruption; targeted disruption of MEKK1 in ES cells abolishes JNK activation and increases apoptosis after taxol treatment; MEKK1 expression is elevated 3-fold in mitosis. |
Targeted gene disruption in embryonic stem cells, JNK kinase assays, cell cycle analysis |
The Journal of biological chemistry |
High |
10212239
|
| 1999 |
MEKK-1 activates Smad2-mediated transcription in endothelial cells independently of the C-terminal SSXS motif of Smad2 (the TGF-β receptor phosphorylation site), increases Smad2 phosphorylation state, enhances Smad2-Smad4 interactions, induces nuclear localization of Smad2/Smad4, and stimulates Smad-coactivator interactions. |
Constitutively active MEKK-1 transfection, Gal4-Smad2 reporter assay, co-immunoprecipitation, nuclear fractionation, shear stress experiment |
The Journal of biological chemistry |
Medium |
10085121
|
| 1999 |
MEKK1-deficient ES cell-derived cardiac myocytes fail to activate JNK in response to oxidative stress, leading to enhanced TNF-α production and increased apoptosis; the MEKK1-JNK pathway negatively regulates TNF-α production to protect cardiac myocytes. |
Targeted gene disruption (MEKK1-/- ES cells), JNK and p38 kinase assays, TNF-α ELISA, apoptosis assays |
Proceedings of the National Academy of Sciences of the United States of America |
High |
10611349
|
| 2000 |
Endogenous MEKK1 physically binds to endogenous ERK2, MEK1, and Raf-1, indicating MEKK1 can scaffold all three kinases of the ERK MAP kinase module. |
Co-immunoprecipitation of endogenous proteins |
The Journal of biological chemistry |
Medium |
10969079
|
| 2000 |
Raf-mediated NF-κB activation is blocked by a dominant-negative form of MEKK1, indicating Raf induces NF-κB via MEKK1 as a membrane shuttle kinase, but not through the classical MEK-ERK cascade. |
Dominant-negative MEKK1, pharmacological pathway inhibitors, NF-κB reporter assays, transformation assays |
Proceedings of the National Academy of Sciences of the United States of America |
Medium |
10758165
|
| 2001 |
Protein kinase G (PKG) directly phosphorylates the N-terminal domain of MEKK1 in vitro, and constitutively active PKG activates JNK1 via a PKG→MEKK1→SEK1→JNK1 pathway; dominant-negative MEKK1 blocks PKG-induced JNK1 activation. |
In vitro kinase assay with purified PKG and MEKK1, dominant-negative MEKK1, JNK1 activation assays |
The Journal of biological chemistry |
Medium |
11278263
|
| 2001 |
RIP (receptor-interacting protein) physically associates with MEKK1 in vitro and in vivo, phosphorylates MEKK1 at Ser-957 and Ser-994, and is required for TNF-α-induced MEKK1 activation; a non-phosphorylatable S957A/S994A MEKK1 mutant fails to be activated by RIP and blocks RIP-induced IKKβ and NF-κB activation. |
Co-immunoprecipitation, in vitro kinase assay, site-directed mutagenesis, RIP-deficient Jurkat cells |
The Journal of biological chemistry |
High |
11369754
|
| 2002 |
Purified active GCK (germinal center kinase, a Ste20 homologue) and TRAF2 activate recombinant MEKK1 in vitro; autophosphorylation within the MEKK1 kinase domain activation loop is required for activation; GCK promotes MEKK1 oligomerization in vivo, suggesting activation via induced oligomerization and autophosphorylation. |
In vitro activation assay with purified proteins, forced oligomerization assay, kinase domain mutagenesis, co-immunoprecipitation |
Molecular and cellular biology |
High |
11784851
|
| 2002 |
MEKK1 is required for inducible urokinase-type plasminogen activator (uPA) expression in response to PMA or FGF-2; MEKK1-deficient fibroblasts show greatly reduced uPA expression and activity, which is restored by MEKK1 transfection; this requires MEKK1-dependent MKK1 and JNK activity. |
MEKK1-/- fibroblasts, re-expression rescue, uPA activity assay, dominant-negative MKK constructs |
The Journal of biological chemistry |
High |
12493778
|
| 2002 |
MEKK1 is essential for Gαq-induced cardiac hypertrophy in vivo; MEKK1 knockout abolishes JNK activation, cardiac mass increase, myocyte enlargement, ANF induction, and ventricular dysfunction caused by Gαq overexpression, while other terminal MAPKs are unaffected. |
MEKK1 gene knockout in mice, ES cell-derived cardiomyocytes, JNK/ERK/p38 kinase assays, echocardiography, histology |
Proceedings of the National Academy of Sciences of the United States of America |
High |
11891332
|
| 2003 |
RhoA, but not Rac or Cdc42, binds to the N-terminal regulatory domain (including the PHD domain) of MEKK1; Rho-GTP stimulates MEKK1 kinase activity up to 10-fold toward MEK4 but does not result in RhoA ubiquitination by MEKK1. |
GST pulldown, in vitro kinase assay, PHD domain cysteine mutagenesis |
The Journal of biological chemistry |
High |
14581471
|
| 2003 |
Glycogen synthase kinase 3β (GSK3β) physically associates with endogenous MEKK1 and activates MEKK1 kinase activity; GSK3β-mediated MEKK1 activation is inhibited by insulin via PI3K; MEKK1 activity is reduced in GSK3β-/- fibroblasts and restored by ectopic GSK3β expression. |
Co-immunoprecipitation of endogenous proteins, in vitro kinase assay, GSK3β knockout fibroblasts, pharmacological inhibition (wortmannin) |
The Journal of biological chemistry |
High |
12584189
|
| 2004 |
GST Mu 1-1 (GST M1-1) directly binds MEKK1 and inhibits its kinase activity in vitro; GST M1-1 co-immunoprecipitates with endogenous MEKK1 in L929 cells, interferes with MEKK1-SEK1 binding, and suppresses MEKK1-mediated apoptosis. |
In vitro binding and kinase assays, endogenous co-immunoprecipitation, co-immunoprecipitation competition assay |
The Journal of biological chemistry |
Medium |
15299005
|
| 2004 |
Ceramide directly binds to MEKK1 in glomerular endothelial cells as shown by radioiodinated photoaffinity labeling and ceramide-coupled Sepharose affinity chromatography; this binding activates the SAPK/JNK cascade, which mediates ceramide-induced apoptosis. |
Photoaffinity labeling with [125I]TID-ceramide, affinity chromatography with ceramide-Sepharose, JNK inhibitor functional assay |
Biochimica et biophysica acta |
Medium |
15164763
|
| 2006 |
MEKK1 PHD/RING finger domain exhibits E3 ubiquitin ligase activity toward c-Jun in vitro and in vivo; MEKK1 mediates ubiquitination-dependent degradation of c-Jun in response to osmotic stress, and MEKK1-/- cells show higher c-Jun protein levels; c-Jun downregulation by MEKK1 promotes apoptosis. |
In vitro ubiquitination assay, MEKK1-/- cell lines, osmotic stress treatment, rescue by c-Jun overexpression |
Molecular and cellular biology |
High |
17101801
|
| 2006 |
MEKK1 is required for CD40-mediated activation of JNK, p38, and c-Jun in B cells; MEKK1 is recruited to CD40 and TRAF2 after CD40 ligation; Map3k1(deltaKD) mice have defective germinal center formation and reduced thymus-dependent antibody production. |
Map3k1 kinase domain knockin mice, kinase assays, co-immunoprecipitation (CD40-TRAF2-MEKK1), B cell proliferation assays, in vivo immunization |
Nature immunology |
High |
17143273
|
| 2006 |
MEKK1 controls mammary tumor cell dissemination and lung metastasis by regulating urokinase-type plasminogen activator (uPA) expression, gelatinase activity, and cell migration/invasion; MEKK1-/- mice with PyMT mammary tumors show delayed tumor cell dissemination associated with reduced uPA and gelatinase activity and prolonged basement membrane integrity. |
MEKK1-/- mouse model with PyMT transgene, siRNA knockdown in MDA-MB-231 cells, gelatin zymography, invasion assay, lung metastasis counts |
Oncogene |
High |
16568086
|
| 2008 |
MEKK1 is an essential component of antiviral signaling downstream of IPS-1 in the RIG-I-like helicase pathway; forced expression of MEKK1 with IRF3 induces IFN-β, whereas MEKK1 siRNA knockdown inhibits IFN-β induction by poly(I:C); MEKK1 mediates NF-κB and MAPK activation but not IRF3 activation in this pathway. |
siRNA knockdown, forced expression, IFN-β promoter reporter assay, TRAF6-/- and TAK1-/- MEF comparison |
The Journal of biological chemistry |
Medium |
18984593
|
| 2010 |
MEKK-1 mediates IL-1β-induced increase in intestinal epithelial tight junction permeability through activation of the canonical NF-κB pathway and MLCK gene activation; MEKK-1 knockdown inhibits these effects, while NIK (non-canonical pathway) knockdown does not affect TJ permeability. |
siRNA knockdown in Caco-2 monolayers, transepithelial resistance measurement, NF-κB pathway inhibitors |
The American journal of pathology |
Medium |
21048223
|
| 2010 |
MAP3K1 interacts with Axin1; the Axin1-MAP3K1 interaction is induced and modulated by Wnt stimulation; MAP3K1 E3 ubiquitin ligase activity (not kinase activity) is required for Wnt/β-catenin-TCF/LEF transcriptional activity; MAP3K1 siRNA abolishes TCF/LEF-driven transcription and Wnt3A-driven endogenous gene expression. |
Immunoprecipitation-coupled proteomics (Axin1 IP-MS), co-IP in HEK293T cells, siRNA knockdown, ubiquitin ligase-dead and kinase-dead mutant transfection, TCF reporter assay |
Biological chemistry |
Medium |
20128690
|
| 2010 |
The WD40-repeat scaffold protein Han11 directly binds MEKK1 in vitro and regulates the threshold and amplitude of MEKK1-triggered stress signaling; Han11 couples MEKK1 to DYRK1 and HIPK2 in a signaling complex; knockdown of Han11 alters the kinetics and amplitude of MEKK1-triggered gene expression. |
In vitro binding assays, knockdown experiments, reporter assays for MEKK1-triggered gene expression |
The EMBO journal |
Medium |
20940704
|
| 2011 |
MAP3K1 integrates TGF-α/EGFR-RhoA signals and JNK-c-Jun signals during eyelid closure; c-Jun (induced by EGFR-RhoA) binds the Map3k1 promoter in a phosphorylation-independent manner to drive MAP3K1 expression; MAP3K1 then phosphorylates JNK-c-Jun to activate AP-1 and downstream targets (PAI-1), forming an intracrine regulatory loop. |
ChIP (c-Jun binding to Map3k1 promoter), RhoA knockout mice, Map3k1 hemizygote mice, JNK-c-Jun phosphorylation assays, PAI-1 expression |
Proceedings of the National Academy of Sciences of the United States of America |
High |
21969564
|
| 2013 |
MAP3K1 missense mutations causing 46,XY disorder of sex development increase binding of RHOA, MAP3K4, and FRAT1 while reducing SOX9/FGF9/SRY expression and increasing WNT/β-catenin/FOXL2 activity; these effects are partially rescued by co-transfection with wild-type MAP3K4. |
Cell transfection with wild-type or mutant MAP3K1 in B-lymphoblastoid and NT2/D1 cells, Western blot for phosphorylation of downstream targets, siRNA phenocopying |
Human molecular genetics |
Medium |
24135036
|
| 2013 |
MAP3K1 encodes both a kinase domain and a PHD/RING finger E3 ubiquitin ligase domain; full-length MAP3K1 regulates cell migration and pro-survival signaling, while its caspase-3 cleavage product promotes apoptosis; the E3 ligase domain ubiquitylates c-Jun and ERK1/2. |
Review synthesizing genetic knockouts, biochemical assays, and ubiquitination assays from multiple studies (not a primary experimental paper, but summarizes established experimental findings) |
Genes & cancer |
Medium |
24386504
|
| 2014 |
The MEKK1 PHD motif functions as an E3 ubiquitin ligase that mediates Lys63-linked poly-ubiquitination of TAB1, using the conjugating enzyme UBE2N; this ubiquitination of TAB1 regulates TAK1 and MAPK (p38 and JNK) activation by TGF-β and EGF; PHD-inactive knockin (Map3k1(mPHD)) cells show defective MAPK responses to TGF-β, EGF, and microtubule disruption but not to hyperosmotic stress. |
Map3k1(mPHD) knockin ES cells and mice, protein microarray substrate profiling, ubiquitination assays (Lys63 linkage), in vitro E3 ligase reconstitution |
The EMBO journal |
High |
25260751
|
| 2014 |
MarvelD3, a tight junction transmembrane component, recruits MEKK1 to junctions; MarvelD3 expression inversely correlates with JNK activity; loss of MarvelD3 increases MEKK1-JNK signaling, cell migration, and proliferation, while re-expression in metastatic cells inhibits these processes. |
MarvelD3 depletion and re-expression, JNK phosphorylation assays, cell migration and proliferation assays, in vivo tumor formation, MEKK1 co-immunoprecipitation |
The Journal of cell biology |
Medium |
24567356
|
| 2018 |
Loss-of-function mutations in MAP3K1 disable the JNK-JUN-mediated feedback loop activated by MEK inhibition (via DUSP4 suppression and HER RTK activation), causing sensitivity to MEK inhibitors; this was confirmed in PDX tumor models. |
Genetic analysis with MEK inhibitor treatment in cancer cell lines and 168 PDX tumors, JNK-JUN pathway readouts, DUSP4 siRNA epistasis |
Cell research |
High |
29795445
|
| 2018 |
MAP3K1 disruption enhances AKT phosphorylation and IRS-1 stability, promotes IRS-1 binding to p85 and PI3Kα activity; this results from deficient MAP3K1-JNK signaling increasing IRS-1 stability, thereby conferring resistance to AKT inhibitors. |
CRISPR knockout of MAP3K1 in PIK3CA-mutant cell lines, Western blot for p-AKT/IRS-1, co-immunoprecipitation (IRS-1/p85), 3D MCF10A models, in vivo xenograft |
Oncotarget |
Medium |
29765551
|
| 2019 |
MAP3K1 mutations causing 46,XY gonadal dysgenesis cluster in three semi-contiguous domains: an N-terminal Guanine Exchange Factor-homology domain (residues 164–231), a PHD domain (residues 442–495), and an ARMadillo repeat domain (residues 566–862); these mutations increase binding of RHOA, MAP3K4, and FRAT1 and decrease binding of RAC1, with differential effects depending on domain location. |
Structural modeling, transfection of mutant MAP3K1 constructs, co-immunoprecipitation for co-factor binding, downstream phosphorylation assays |
Human molecular genetics |
Medium |
30608580
|