Affinage

MAP3K10

Mitogen-activated protein kinase kinase kinase 10 · UniProt Q02779

Length
954 aa
Mass
103.7 kDa
Annotated
2026-06-10
18 papers in source corpus 10 papers cited in narrative 11 extracted findings
Cross-family judge faithfulness: 8/8 claims corpus-supported (100%)

Mechanistic narrative

Synthesis pass · prose summary of the discoveries below

MAP3K10 (MLK2) is a mixed-lineage MAP kinase kinase kinase that nucleates activation of stress-responsive MAPK cascades, most prominently the JNK/SAPK pathway, by directly phosphorylating and activating SEK1/MKK4 (PMID:9182538). Its output spans JNK, ERK, and p38, with strongest and constitutive activation of JNK upon expression (PMID:9427749). Activation is controlled by small GTPase input: MLK2 binds GTP-loaded Rac and Cdc42 (preferring Rac) through its CRIB motif, links to KIF3 kinesin motor complexes and the KAP3A targeting subunit, and co-localizes with active JNK along microtubules (PMID:9427749). A feedback loop refines its function — activated JNK2 phosphorylates MLK2 at multiple sites in its noncatalytic C-terminal region, and this C-terminal domain is required for MLK2-induced apoptosis even though the N-terminal catalytic domain alone suffices to activate JNK (PMID:11278395). MLK2 is recruited into JNK-activating complexes through scaffolding and adaptor interactions, including normal huntingtin (an interaction disrupted by polyglutamine expansion), HAP1, and PAK1 acting via the NCK adapter (PMID:10801775, PMID:12753919). Beyond canonical MAPK substrates, MLK2 phosphorylates the bHLH transcription factor NeuroD to stimulate its transcriptional activity in a huntingtin/HAP1-facilitated manner (PMID:12881483), and phosphorylates GlyRS downstream of a GPR87-CDC42/Rac1 axis to activate NFκB1 (PMID:31954518). In TGFβ signaling, MAP3K10 together with MAP3K4 are sufficient mediators of TGFβ-induced p38 activation, with TAK1/MAP3K7 excluded in this context (PMID:23760366). An in vivo developmental role is established in Xenopus, where MLK2 is required for cement gland and pronephric tubule formation (PMID:12591241).

Mechanistic history

Synthesis pass · year-by-year structured walk · 11 steps
  1. 1997 High

    Established MLK2 as a bona fide MAP3K by demonstrating it directly phosphorylates and activates the JNK-pathway MAP2K SEK1/MKK4, placing it upstream in stress kinase signaling.

    Evidence In vitro kinase assay with bacterially expressed recombinant MLK2 plus COS-1 overexpression

    PMID:9182538

    Open questions at the time
    • Did not define physiological upstream activators
    • Relative contribution to ERK/p38 versus JNK not resolved here
  2. 1998 High

    Defined how MLK2 is activated and spatially organized — GTP-Rac/Cdc42 binding via the CRIB motif and association with KIF3/KAP3A motors targeting it along microtubules with active JNK.

    Evidence Yeast two-hybrid, in vitro dot-blot, COS transfection, immunofluorescence co-localization

    PMID:9427749

    Open questions at the time
    • Mechanistic consequence of microtubule localization for signaling output not established
    • Direct kinetic effect of GTPase binding on kinase activity not quantified
  3. 1998 Medium

    Showed MLK2 engages multiple MAPK cascades in cells, with preferential JNK activation, defining its signaling breadth.

    Evidence COS cell transfection with kinase activity assays

    PMID:9427749

    Open questions at the time
    • Overexpression context may overstate ERK/p38 engagement
    • Endogenous selectivity untested
  4. 2000 Medium

    Linked MLK2 to neuronal apoptosis and disease, showing huntingtin binds MLK2, polyQ expansion disrupts this, and dominant-negative MLK2 blunts polyQ-huntingtin-induced death.

    Evidence Reciprocal Co-IP, dominant-negative transfection, JNK and apoptosis assays in HN33 neuronal cells

    PMID:10801775

    Open questions at the time
    • Single-lab functional epistasis
    • Direct causal role in vivo not shown
  5. 2001 High

    Uncovered a JNK→MLK2 feedback loop, mapping JNK2 phosphorylation to the C-terminal region and showing this domain is required for the apoptotic, but not the JNK-activating, function of MLK2.

    Evidence Phosphopeptide mapping, in vitro kinase assay with activated JNK2, dominant-negative JNK cotransfection, deletion mutants

    PMID:11278395

    Open questions at the time
    • Specific phosphosites and their individual contributions not resolved
    • Downstream effectors of C-terminal phosphorylation unknown
  6. 2003 Medium

    Expanded MLK2 substrate repertoire beyond MAP2Ks by showing it phosphorylates and activates the transcription factor NeuroD, with huntingtin/HAP1 serving as scaffold.

    Evidence Yeast two-hybrid, in vitro kinase assay, transcription reporter assays, Co-IP

    PMID:12881483

    Open questions at the time
    • Phosphosites on NeuroD not mapped
    • Physiological/in vivo relevance unestablished
  7. 2003 Medium

    Identified PAK1 as a catalytic-domain partner that recruits MLK2 (via NCK) but squelches its JNK activation, indicating receptor-coupled regulation of MLK2 output.

    Evidence Co-IP, overexpression/squelching assays, JNK activity assays

    PMID:12753919

    Open questions at the time
    • Single paper, single lab
    • Direct NCK-MLK2-PAK1 ternary complex at a receptor not demonstrated
  8. 2003 Medium

    Provided in vivo evidence for an organismal role, showing Xenopus MLK2 activates JNK via SEK1/MKK4 and is required for cement gland and pronephric tubule development.

    Evidence Antisense knockdown, dominant-negative overexpression, COS7 kinase assay, in situ hybridization

    PMID:12591241

    Open questions at the time
    • Mammalian developmental role not directly demonstrated
    • Tissue-specific effectors unknown
  9. 2012 Low

    Implicated MAP3K10 in pancreatic cancer cell proliferation and gemcitabine resistance through Hedgehog/Gli upregulation.

    Evidence Overexpression and shRNA knockdown, proliferation assays, Western blotting for Gli-1/Gli-2

    PMID:23178452

    Open questions at the time
    • No direct kinase-substrate experiment linking MAP3K10 to GLI
    • Mechanism connecting MAP3K10 to Hedgehog signaling unresolved
  10. 2013 High

    Placed MAP3K10 in the TGFβ→p38 pathway, showing it and MAP3K4 are sufficient mediators of TGFβ-induced p38 phosphorylation while excluding TAK1.

    Evidence RNAi knockdown, catalytically inactive MAP3K4 knock-in cells, p38 phospho-immunoblotting in MEFs and HaCaT cells

    PMID:23760366

    Open questions at the time
    • Whether MAP3K10 acts on the same MAP2Ks as MAP3K4 not resolved
    • Direct substrate in the TGFβ context not identified
  11. 2020 Medium

    Defined a methionine-responsive signaling axis where GPR87-CDC42/Rac1 activates MAP3K10 to phosphorylate GlyRS, which in turn activates NFκB1.

    Evidence Co-IP, mass spectrometry, in vitro kinase assay, pathway knockdown/inhibition in bovine mammary epithelial cells

    PMID:31954518

    Open questions at the time
    • GlyRS phosphosites not fully defined
    • Generalizability beyond mammary epithelial context untested

Open questions

Synthesis pass · forward-looking unresolved questions
  • How MAP3K10 selects among JNK, ERK, and p38 outputs and among canonical versus non-canonical substrates in a given cellular and developmental context remains unresolved.
  • No structural model of GTPase/scaffold-gated activation
  • Endogenous substrate selectivity not systematically mapped
  • Mammalian loss-of-function phenotype undefined

Mechanism profile

Synthesis pass · controlled-vocabulary classification · explore literature graph →
Molecular activity
GO:0140096 catalytic activity, acting on a protein 4 GO:0016740 transferase activity 3 GO:0140657 ATP-dependent activity 1
Localization
GO:0005829 cytosol 1 GO:0005856 cytoskeleton 1
Pathway
R-HSA-162582 Signal Transduction 3 R-HSA-5357801 Programmed Cell Death 2
Partners
CDC42GARS1HAP1HTTKAP3AMAP2K4PAK1RAC1

Evidence

Reading pass · 11 per-paper findings extracted from the source corpus
Year Finding Method Journal Conf PMIDs
1997 MLK2/MST (MAP3K10) directly phosphorylates and activates SEK1/MKK4/JNKK in vitro, establishing it as a MAP kinase kinase kinase that preferentially activates the JNK/SAPK pathway; recombinant MLK2 produced in bacteria phosphorylated SEK1 in an in vitro kinase assay. In vitro kinase assay with bacterially expressed recombinant MLK2; COS-1 cell overexpression The Journal of biological chemistry High 9182538
1998 MLK2 interacts with the GTP-bound (activated) forms of Rac and Cdc42 (preferring Rac) via its CRIB motif, as shown by yeast two-hybrid and in vitro dot-blot assays. MLK2 also interacts with members of the KIF3 kinesin superfamily motor proteins and with KAP3A (the targeting component of KIF3 complexes), and co-localizes with dually phosphorylated (active) JNK1/2 along microtubules in fibroblasts. Yeast two-hybrid, in vitro dot-blot, COS cell transfection, immunofluorescence co-localization The EMBO journal High 9427749
1998 Transfection of MLK2 into COS cells leads to activation of the JNK, ERK, and p38 MAP kinase cascades, with strongest and constitutive activation of JNK. COS cell transfection with kinase activity assays The EMBO journal Medium 9427749
2000 Normal huntingtin interacts with MLK2, and polyglutamine expansion of huntingtin disrupts this interaction. Expression of MLK2 induces JNK activation and apoptosis in HN33 neuronal cells; dominant-negative MLK2 attenuates apoptosis induced by polyglutamine-expanded huntingtin. Co-immunoprecipitation, transfection with dominant-negative constructs, JNK activity assay, apoptosis assay The Journal of biological chemistry Medium 10801775
2001 Activated JNK2 phosphorylates MLK2 at multiple sites predominantly in its noncatalytic C-terminal region both in vitro and in vivo. The C-terminal domain of MLK2 is required for MLK2-induced apoptosis (N-terminal domain alone can activate JNK but is insufficient for apoptosis), identifying a feedback phosphorylation loop where JNK phosphorylates MLK2 to enable its apoptotic function. Phosphopeptide mapping, in vitro kinase assay with activated JNK2, cotransfection with dominant-negative JNK kinase, deletion mutant analysis The Journal of biological chemistry High 11278395
2003 MLK2 phosphorylates the NeuroD basic helix-loop-helix transcription factor and stimulates its transcriptional activity. Huntingtin and HAP1 interact with NeuroD and facilitate activation of NeuroD by MLK2, suggesting a scaffold function for Htt/HAP1 in MLK2-mediated NeuroD activation. Yeast two-hybrid screen, in vitro kinase assay, transcription reporter assays, co-immunoprecipitation Proceedings of the National Academy of Sciences of the United States of America Medium 12881483
2003 PAK1 and MLK2 interact via their catalytic domains and PAK1 squelches MLK2-mediated JNK activation, suggesting that PAK1 recruits MLK2 to an activated receptor via the NCK adapter but cannot itself induce JNK cascade activation. Co-immunoprecipitation, overexpression/squelching assays, JNK activity assays FEBS letters Medium 12753919
2003 Xenopus MLK2 (62% homology to mammalian MLK2) activates JNK in a SEK1/MKK4-dependent manner in COS7 cells. In vivo antisense inactivation and dominant-negative xMLK2 show that xMLK2 is required for normal cement gland development and pronephric tubule formation, establishing a tissue-restricted in vivo role for MLK2 in organogenesis. Antisense knockdown, dominant-negative overexpression, COS7 cell transfection with kinase assay, in situ hybridization Developmental biology Medium 12591241
2013 RNAi-mediated depletion of MAP3K10 inhibits TGFβ-induced p38 MAPK phosphorylation in MEFs and HaCaT keratinocytes. Depletion of MAP3K10 from cells carrying a catalytically inactive MAP3K4 knock-in completely abolishes TGFβ-induced p38 phosphorylation, placing MAP3K10 and MAP3K4 as sufficient mediators of TGFβ→p38 signaling (and ruling out TAK1/MAP3K7 in this context). RNAi knockdown, catalytically inactive MAP3K4 knock-in cells, immunoblotting for p38 phosphorylation Open biology High 23760366
2020 MAP3K10 interacts with and phosphorylates GlyRS (glycyl-tRNA synthetase) in bovine mammary epithelial cells, acting as an upstream kinase of GlyRS. This phosphorylation is stimulated by methionine through the GPR87-CDC42/Rac1-MAP3K10 signaling axis. Phosphorylated GlyRS then activates NFκB1. Co-immunoprecipitation, mass spectrometry, Western blotting, in vitro kinase assay, signaling pathway knockdown/inhibition Biochemical and biophysical research communications Medium 31954518
2012 MAP3K10 overexpression in pancreatic cancer cells upregulates Hedgehog pathway components Gli-1 and Gli-2, promoting cell proliferation and decreasing gemcitabine sensitivity; MAP3K10 knockdown decreases proliferation and sensitizes cells to gemcitabine, but neither manipulation affects cell migration. Overexpression and shRNA knockdown, viability/proliferation assays, Western blotting for Gli-1/Gli-2 Cancer letters Low 23178452

Source papers

Stage 0 corpus · 18 papers · ranked by NIH iCite citations
Year Title Journal Citations PMID
1998 The MAP kinase kinase kinase MLK2 co-localizes with activated JNK along microtubules and associates with kinesin superfamily motor KIF3. The EMBO journal 228 9427749
1997 MST/MLK2, a member of the mixed lineage kinase family, directly phosphorylates and activates SEK1, an activator of c-Jun N-terminal kinase/stress-activated protein kinase. The Journal of biological chemistry 168 9182538
2012 Regulation of microRNA-155 in atherosclerotic inflammatory responses by targeting MAP3K10. PloS one 113 23189122
2000 Activation of MLK2-mediated signaling cascades by polyglutamine-expanded huntingtin. The Journal of biological chemistry 68 10801775
2003 Stimulation of NeuroD activity by huntingtin and huntingtin-associated proteins HAP1 and MLK2. Proceedings of the National Academy of Sciences of the United States of America 61 12881483
1997 Two-dimensional electrophoretic analysis of human breast carcinoma proteins: mapping of proteins that bind to the SH3 domain of mixed lineage kinase MLK2. Electrophoresis 41 9150946
2013 The TGFβ-induced phosphorylation and activation of p38 mitogen-activated protein kinase is mediated by MAP3K4 and MAP3K10 but not TAK1. Open biology 23 23760366
2012 MAP3K10 promotes the proliferation and decreases the sensitivity of pancreatic cancer cells to gemcitabine by upregulating Gli-1 and Gli-2. Cancer letters 21 23178452
2008 Mice lacking both mixed-lineage kinase genes Mlk1 and Mlk2 retain a wild type phenotype. Cell cycle (Georgetown, Tex.) 21 18414056
2001 Activated JNK phosphorylates the c-terminal domain of MLK2 that is required for MLK2-induced apoptosis. The Journal of biological chemistry 21 11278395
2021 MiR-146b-3p regulates proliferation of pancreatic cancer cells with stem cell-like properties by targeting MAP3K10. Journal of Cancer 20 33995647
2003 PAK interacts with NCK and MLK2 to regulate the activation of jun N-terminal kinase. FEBS letters 15 12753919
2020 Methionine stimulates GlyRS phosphorylation via the GPR87-CDC42/Rac1-MAP3K10 signaling pathway. Biochemical and biophysical research communications 14 31954518
2003 A tissue restricted role for the Xenopus Jun N-terminal kinase kinase kinase MLK2 in cement gland and pronephric tubule differentiation. Developmental biology 13 12591241
2017 MicroRNA-155 targets MAP3K10 and regulates osteosarcoma cell growth. Pathology, research and practice 7 28214207
2020 DNA methylation‑regulated miR‑155‑5p depresses sensitivity of esophageal carcinoma cells to radiation and multiple chemotherapeutic drugs via suppression of MAP3K10. Oncology reports 6 32323857
2018 MLK1 and MLK2 integrate gibberellins and circadian clock signaling to modulate plant growth. Plant signaling & behavior 6 29431572
2022 DNA methylation of the MAP3K10 gene may participate in the development of intracranial aneurysm. Gene 4 36341729

Missed literature

Know a paper Affinage missed for MAP3K10? Flag it for the maintainers and the community.

No submissions yet.