Affinage

ARAF

Serine/threonine-protein kinase A-Raf · UniProt P10398

Length
606 aa
Mass
67.6 kDa
Annotated
2026-04-28
100 papers in source corpus 36 papers cited in narrative 35 extracted findings

Mechanistic narrative

Synthesis pass · prose summary of the discoveries below

ARAF is a serine/threonine kinase of the RAF family that functions as both an enzymatic activator of MEK1 and a kinase-independent scaffold within the RAS-MAPK signaling cascade. ARAF selectively phosphorylates MEK1 but not MEK2, with intrinsic catalytic activity far lower than BRAF or CRAF, governed by isoform-specific regulatory elements including the N-region residue Y296 and a positively-regulating IH-segment (residues 248–267) (PMID:8621729, PMID:17613527, PMID:18662992). Beyond its kinase role, ARAF stabilizes BRAF:CRAF heterodimers to promote MAPK signaling, displaces NF1 from RAS to prolong RAS-GTP signaling kinase-independently, sequesters the proapoptotic kinase MST2 at mitochondria to inhibit apoptosis under control of KSR2-regulated subcellular localization, and suppresses ERBB3 expression via KLF5 (PMID:22926515, PMID:35613620, PMID:20145135, PMID:26891695, PMID:35302851). Alternative splicing controlled by c-Myc/hnRNP H produces a dominant-negative short isoform that antagonizes RAS-ERK signaling, while gain-of-function mutations such as S214P/C confer oncogenic activity and resistance to RAF inhibitors through dimer-dependent mechanisms (PMID:21512137, PMID:24652991, PMID:33953400).

Mechanistic history

Synthesis pass · year-by-year structured walk · 14 steps
  1. 1995 High

    Establishing that ARAF is a functional MEK/MAPK activating kinase, but with dramatically lower intrinsic activity than BRAF or CRAF, raised the question of what ARAF's specific contribution to MAPK signaling is.

    Evidence In vitro immune-complex kinase assays with Sf9-expressed RAF isoforms and conditional ER-fusion system in NIH 3T3 cells

    PMID:7565795 PMID:7592840

    Open questions at the time
    • Structural basis for ~500-fold lower activity versus BRAF not explained
    • Whether ARAF has kinase-independent functions not addressed
  2. 1996 High

    Discovery that ARAF selectively activates MEK1 but not MEK2, and that ARAF knockout causes postnatal lethality with neurological/GI defects, established isoform-specific substrate selectivity and essential in vivo roles.

    Evidence Yeast two-hybrid screen and in vitro MEK1/MEK2 kinase assays in HeLa cells; gene knockout mice with phenotypic analysis

    PMID:8621729 PMID:8805280

    Open questions at the time
    • Molecular basis for MEK1 selectivity over MEK2 undefined
    • Which ARAF functions are responsible for the in vivo phenotype unclear
  3. 1997 High

    Identification of CK2β as an ARAF-specific activator and of key regulatory tyrosines in the kinase domain revealed how ARAF's low basal activity is maintained and can be modulated by isoform-specific protein interactions.

    Evidence Yeast two-hybrid, Sf9 co-expression kinase assay with CK2β domain mapping; mutagenesis of activation loop tyrosines with transformation and kinase assays

    PMID:9042965 PMID:9285556

    Open questions at the time
    • Physiological context where CK2β activates ARAF not established
    • Full structural model of ARAF regulation lacking
  4. 2000 High

    Localization of ARAF to mitochondria via hTOM/hTIM interactions and identification of a constitutive ARAF–PI3K-p85 complex revealed unexpected subcellular compartmentalization and cross-talk with PI3K signaling.

    Evidence Immunogold electron microscopy of purified mitochondria; yeast two-hybrid and Co-IP for hTOM/hTIM; phage display and reciprocal Co-IP for p85 interaction with mutagenesis of K50/R52

    PMID:10848612 PMID:10967104

    Open questions at the time
    • Functional consequence of mitochondrial ARAF not yet defined
    • Whether p85 interaction modulates ARAF kinase activity or localization unclear
  5. 2002 High

    ARAF knockout MEFs showed normal ERK activation with compensatory upregulation of BRAF/CRAF, indicating redundancy among RAF isoforms but also suggesting non-canonical ARAF functions might be masked.

    Evidence ARAF-null MEFs and ES cells with kinase cascade assays, proliferation, apoptosis, and transformation readouts

    PMID:11821947

    Open questions at the time
    • Non-canonical ARAF functions not investigated in this system
    • Tissue-specific requirements versus MEF context not explored
  6. 2005 High

    Double knockout of ARAF and CRAF revealed their combined, non-redundant role in transient ERK activation and G1/S progression, while lipid-binding studies showed ARAF uniquely binds PI(4,5)P2 and PA through its RBD.

    Evidence Double KO mice embryonic lethal at E10.5 with MEF cell cycle analysis; lipid overlay assay with K50/R52 mutagenesis

    PMID:15736953 PMID:15856007

    Open questions at the time
    • How lipid binding contributes to ARAF regulation in cells not established
    • Relative contributions of ARAF kinase versus scaffold functions in double-KO phenotype unknown
  7. 2007 High

    Identification of Y296 as the N-region residue restricting ARAF basal activity, and the IH-segment as a positive regulatory element, provided the molecular logic for why ARAF is intrinsically less active than other RAF isoforms.

    Evidence Site-directed mutagenesis with kinase activity assays; mass spectrometry-based phosphosite mapping with mutagenesis and MEK binding assays

    PMID:17613527 PMID:18662992

    Open questions at the time
    • Crystal structure of ARAF autoinhibited state not available
    • How IH-segment phosphorylation is regulated in vivo unclear
  8. 2010 High

    Demonstration that ARAF sequesters and inactivates MST2 kinase-independently to prevent apoptosis, controlled by c-Myc/hnRNP H-regulated alternative splicing of ARAF mRNA, established a major non-catalytic tumor survival function and its post-transcriptional regulation.

    Evidence Reciprocal Co-IP of ARAF:MST2 complex, siRNA knockdown with apoptosis assays; RT-PCR splicing analysis with c-Myc/hnRNP H manipulation

    PMID:20145135 PMID:21512137

    Open questions at the time
    • Structural basis of ARAF-MST2 interaction undefined
    • Whether the short ARAF isoform has physiological functions beyond dominant-negative activity unknown
  9. 2012 High

    ARAF was shown to function as a scaffold stabilizing BRAF:CRAF heterodimers, explaining how ARAF contributes to MAPK signaling beyond its own weak kinase activity and how RAF inhibitors paradoxically activate the pathway.

    Evidence Reciprocal Co-IP of RAF dimers, siRNA depletion, RAF inhibitor treatment with signaling readouts

    PMID:22926515

    Open questions at the time
    • Stoichiometry of ARAF in trimeric versus dimeric RAF complexes not determined
    • Whether ARAF scaffold function is regulated independently of its kinase activity unknown
  10. 2013 High

    Discovery that ARAF directly phosphorylates Smad2 at linker S253 to accelerate its degradation established a MEK/ERK-independent role for ARAF in attenuating TGF-β/Nodal signaling during embryonic development.

    Evidence In vitro kinase assay with site-directed mutagenesis of Smad2-S253; zebrafish morpholino knockdown with rescue

    PMID:23591895

    Open questions at the time
    • Whether ARAF-Smad2 interaction occurs in mammalian development not shown
    • Whether other RAF isoforms can phosphorylate Smad2 not tested
  11. 2014 High

    Gain-of-function ARAF mutations (S214P/C, compound kinase domain mutations) were shown to be oncogenic drivers in lung adenocarcinoma and Langerhans cell histiocytosis, sensitive to RAF/MEK inhibitors, establishing ARAF as a bona fide cancer gene.

    Evidence In vitro kinase assays with mutant ARAF, transformation assays, vemurafenib/sorafenib sensitivity; BRET dimerization assays showing obligatory ARAF dimerization for MEK activation

    PMID:24569458 PMID:24652991 PMID:25097033

    Open questions at the time
    • Frequency and spectrum of ARAF mutations across cancer types incompletely characterized
    • Whether S214P activates through dimer-dependent or dimer-independent mechanisms not fully resolved
  12. 2016 High

    KSR2 was identified as the regulator controlling ARAF subcellular localization: in proliferating cells KSR2 retains ARAF at mitochondria where it sequesters MST2, while KSR2 downregulation during differentiation relocalizes ARAF to the plasma membrane and permits apoptosis.

    Evidence Confocal microscopy, subcellular fractionation, KSR2 siRNA knockdown, apoptosis assays in MCF7 differentiation model

    PMID:26891695

    Open questions at the time
    • Molecular mechanism by which KSR2 retains ARAF at mitochondria not defined
    • Whether this localization switch operates in non-breast cell types unknown
  13. 2020 High

    ARAF was identified as a critical mediator of resistance to RAF dimer inhibitors (belvarafenib, LXH254) through a mechanism requiring both ARAF kinase activity and dimerization, explaining clinical treatment failures.

    Evidence Belvarafenib-resistant cell line generation, CRISPR/siRNA ARAF ablation, kinase-dead and dimer-deficient ARAF mutant rescue, in vivo xenografts, circulating tumor DNA analysis

    PMID:33355204 PMID:33953400

    Open questions at the time
    • Whether next-generation pan-RAF inhibitors overcome ARAF-mediated resistance unknown
    • Structural basis of how ARAF dimers remain active in the presence of inhibitor not resolved
  14. 2022 High

    Two kinase-independent ARAF functions were discovered: displacing NF1 from RAS to prolong RAS-GTP signaling, and suppressing ERBB3 transcription via KLF5, establishing ARAF as a multifunctional signaling node beyond the canonical RAF-MEK cascade.

    Evidence Co-IP of ARAF-RAS and ARAF-NF1, RAS-GTP pull-down with kinase-dead rescue; ERBB3 promoter reporter assay with kinase-dead ARAF rescue and metastasis assays

    PMID:35302851 PMID:35613620

    Open questions at the time
    • Whether NF1 displacement is specific to ARAF or shared by other RAF isoforms not fully tested
    • How ARAF regulates KLF5 activity mechanistically unknown
    • Whether ARAF-RAS and ARAF-NF1 interactions are regulated by the same signals unclear

Open questions

Synthesis pass · forward-looking unresolved questions
  • Key open questions include the structural basis for ARAF's autoinhibited state and low intrinsic kinase activity, the mechanism by which KSR2 controls ARAF mitochondrial retention, how ARAF regulates KLF5 to suppress ERBB3, and whether ARAF's multiple kinase-independent functions are coordinated or context-dependent.
  • No crystal structure of full-length ARAF available
  • Mechanism of KSR2-dependent mitochondrial retention undefined
  • ARAF-KLF5 interaction mechanism not characterized
  • Relative importance of kinase-dependent versus kinase-independent functions in different tissues unknown

Mechanism profile

Synthesis pass · controlled-vocabulary classification · explore literature graph →
Molecular activity
GO:0140096 catalytic activity, acting on a protein 8 GO:0060090 molecular adaptor activity 2 GO:0098772 molecular function regulator activity 2 GO:0008289 lipid binding 1
Localization
GO:0005739 mitochondrion 2 GO:0005829 cytosol 2 GO:0005886 plasma membrane 1
Pathway
R-HSA-162582 Signal Transduction 9 R-HSA-1643685 Disease 4 R-HSA-5357801 Programmed Cell Death 2 R-HSA-1266738 Developmental Biology 1 R-HSA-1640170 Cell Cycle 1
Partners
BRAFCSNK2BKSR2MAP2K1MST2NF1PIK3R1RAF1
Complex memberships
ARAF:MEK1 signaling complexARAF:MST2 anti-apoptotic complexBRAF:CRAF heterodimer (stabilized by ARAF)

Evidence

Reading pass · 35 per-paper findings extracted from the source corpus
Year Finding Method Journal Conf PMIDs
1995 A-Raf kinase domain activates MEK and p42/p44 MAP kinases, but is approximately 500-fold less active than B-Raf and ~10-fold less active than Raf-1 at phosphorylating and activating MEK1 in vitro immune-complex kinase assays; oncogenic A-Raf:ER fusion induces S-phase entry in quiescent 3T3 cells, a property distinct from B-Raf:ER and Raf-1:ER. Conditional estrogen-receptor fusion system in NIH 3T3 cells, in vitro immune-complex kinase assays, Sf9 insect cell expression, MEK/MAPK activation assays Molecular and cellular biology High 7565795
1996 A-Raf selectively phosphorylates and activates MEK1 but not MEK2 following EGF stimulation of HeLa cells; A-Raf interacts with a substrate-trapping MEK1(S218A/S222A) mutant but not wild-type MEK1 in yeast two-hybrid screening, suggesting the interaction is stabilized when phosphorylation sites are removed. Yeast two-hybrid screen, in vitro MEK1/MEK2 kinase assays, EGF stimulation of HeLa cells The Journal of biological chemistry High 8621729
1996 A-Raf knockout mice exhibit post-natal lethality with neurological and gastrointestinal defects, establishing an essential in vivo role for A-Raf in neurological and intestinal tissue homeostasis. Homologous recombination-mediated gene knockout in mouse embryonic stem cells; phenotypic analysis of null mice Current biology : CB High 8805280
1995 Both c-Raf and A-Raf are activated by hypertrophic stimuli (TPA, endothelin-1) in neonatal rat cardiomyocytes; both isoforms phosphorylate, activate, and form complexes with MEK1 in vitro, but are differentially regulated — TPA produces sustained A-Raf activation and transient c-Raf activation, while cAMP-dependent protein kinase inhibits c-Raf more strongly than A-Raf. In vitro kinase assays, immunoprecipitation-kinase cascade assay, pharmacological modulators in primary cardiomyocytes The Journal of biological chemistry High 7592840
1997 CK2β (regulatory subunit of protein kinase CK2) specifically interacts with A-Raf but not B-Raf or c-Raf-1, and co-expression of CK2β with A-Raf in Sf9 cells enhances A-Raf kinase activity ~10-fold; residues 550–569 in the A-Raf kinase domain mediate this interaction; the CK2α catalytic subunit abolishes the activating effect of CK2β. Yeast two-hybrid screen, Sf9 co-expression kinase assay, co-immunoprecipitation, domain mapping FEBS letters High 9042965 9042966
1997 Mutation of two key tyrosine residues (analogous to B-Raf aspartates) to aspartate in the A-Raf kinase domain (~10-fold increase in catalytic activity) or phenylalanine (decreased activity) demonstrates that these tyrosines are critical negative regulators of A-Raf basal kinase activity and oncogenic potential; B-Raf's higher intrinsic activity cannot be explained solely by the aspartate substitutions at these positions. Site-directed mutagenesis of deltaA-Raf:ER and deltaRaf-1:ER in mammalian cells and Sf9 cells; in vitro kinase assays; transformation assays Oncogene High 9285556
1999 A-Raf (but not B-Raf) is activated downstream of PI3-K in IL-3-stimulated myeloid progenitor cells; dominant-negative A-Raf blocks MEK/ERK activation whereas dominant-negative c-Raf does not, indicating A-Raf is the primary mediator linking PI3-K signaling to MEK in these cells; A-Raf activation is insensitive to cAMP unlike c-Raf. Pharmacological PI3-K inhibition (wortmannin/LY294002), dominant-negative Raf isoform expression, immune-complex kinase assays in IL-3-dependent myeloid cells The Journal of biological chemistry High 10066754
2000 A-RAF localizes specifically to mitochondria in rat liver cells (shown by Western analysis and immunogold labeling of highly purified mitochondria); two novel A-RAF-specific interacting proteins hTOM and hTIM (mitochondrial outer and inner membrane import receptor components) were identified; 14-3-3 interacts with C-RAF but not A-RAF N-terminal domain. Subcellular fractionation, Western blot, immunogold electron microscopy, yeast two-hybrid, co-immunoprecipitation Molecular and cellular biology High 10848612
2000 A-Raf associates with the p85 subunit of PI3-K via a phosphotyrosine-independent SH2 domain interaction requiring basic residues (K50 and R52) in the A-Raf Ras-binding domain; p85 and A-Raf exist in a constitutive complex in cells regardless of growth factor stimulation. Phage display peptide library, direct in vitro binding assay, co-immunoprecipitation from quiescent and growth-factor stimulated cells, mutagenesis The Journal of biological chemistry High 10967104
2002 A-Raf-deficient mouse embryonic fibroblasts (MEFs) and ES cells show no disruption of ERK activation, proliferation, differentiation, apoptosis, or transformation by oncogenic Ras/Src; however, B-Raf and Raf-1 kinase activities toward MEK are both significantly elevated in A-Raf-null MEFs, suggesting compensatory upregulation. Gene targeting to generate A-Raf null MEFs and ES cells; immunoprecipitation-kinase cascade assays; proliferation, apoptosis, and transformation assays Oncogene High 11821947
2005 Double knockout of A-raf and Raf-1 in mice causes embryonic lethality at E10.5, more severe than either single KO; double-KO MEFs show delayed S-phase entry, reduced transient MEK/ERK phosphorylation, and reduced c-Fos and cyclin D1 expression, revealing a combined role for A-Raf and Raf-1 in transient ERK activation and G1/S cell cycle progression. Double gene knockout in mice by homologous recombination; MEF generation; Ki67 staining; BrdU/cell cycle analysis; MEK/ERK kinase assays Oncogene High 15856007
2007 A-Raf interacts with and regulates pyruvate kinase M2 (M2-PK): in primary fibroblasts A-Raf induces M2-PK dimerization and inactivation reducing glycolysis, while oncogenic A-Raf in NIH3T3 cells increases the tetrameric active form of M2-PK promoting glycolytic energy production. Co-immunoprecipitation, M2-PK activity and oligomerization assays, metabolic flux measurements in A-Raf-expressing vs. control cells Anticancer research Medium 18225557
2007 A-Raf's unique N-region residue tyrosine-296 (not present in B-RAF or C-RAF) restricts A-Raf to low basal activity; substituting Y296 with arginine creates a constitutively active A-Raf; introduction of glycine at the analogous C-RAF position (S339G) similarly activates C-RAF; molecular modeling suggests these residues govern N-region contact with the catalytic domain. Site-directed mutagenesis, kinase activity assays, molecular modeling based on B-Raf crystal structure The Journal of biological chemistry High 17613527
2008 Mass spectrometry identified novel in vivo A-RAF phosphorylation sites; Ser-432 is required for MEK binding and is indispensable for A-RAF signaling; a novel IH-segment (residues 248–267) containing Ser-257, Ser-262, and Ser-264 positively regulates A-RAF activation; phosphorylation within the activation segment does not contribute to EGF-mediated A-RAF activation; 14-3-3 binding sites are phosphorylated independently of activation status. Mass spectrometry (in vivo phosphoproteomics), site-directed mutagenesis, MEK binding assays, kinase activity assays The Journal of biological chemistry High 18662992
2009 A-RAF functions in ARF6-regulated endocytic recycling: an N-terminal A-RAF fragment (AR149/DA-RAF2) colocalizes with ARF6 on tubular endosomes, acts as a dominant negative on endocytic trafficking (blocking recycling but not internalization), and abolishes actin polymerization; A-RAF-controlled MEK-ERK signaling is required for ARF6 activation and endosomal recycling. Confocal microscopy colocalization, dominant-negative overexpression, transferrin recycling assay, A-RAF siRNA depletion, MEK/ERK inhibitor studies PloS one Medium 19247477
2010 A-Raf prevents cancer cell apoptosis by sequestering and inactivating the proapoptotic MST2 kinase in a kinase-independent manner; this anti-apoptotic function depends on hnRNP H splice factor-controlled correct transcription/expression of full-length A-Raf; siRNA knockdown of hnRNP H or A-Raf leads to MST2-dependent apoptosis. siRNA knockdown, co-immunoprecipitation (MST2-A-Raf complex), apoptosis assays, overexpression rescue experiments Cancer research High 20145135
2011 c-Myc positively controls hnRNP H expression, which in turn regulates splicing of a-raf mRNA to produce full-length A-Raf; low c-Myc shifts splicing to produce A-Raf(short)/A-Raf-short, a truncated dominant-negative isoform retaining the Ras-binding domain that suppresses Ras activation and ERK signaling without inhibiting MST2. RT-PCR splicing analysis, Western blot, overexpression and knockdown of c-Myc and hnRNP H, ERK activation assays, transformation assays Cancer research High 21512137
2012 ARAF acts as a scaffold to stabilize BRAF:CRAF heterodimers; ARAF binds to and is activated by BRAF, and also forms complexes with CRAF; two cancer-associated ARAF mutations inactivate its kinase; ARAF cannot substitute for CRAF downstream of RAS; ARAF stabilizes BRAF:CRAF complexes in RAF-inhibitor-treated cells thereby regulating paradoxical MAPK pathway activation. Co-immunoprecipitation, kinase activity assays, siRNA depletion, RAF inhibitor treatment, dominant-negative and cancer mutant expression Oncogene High 22926515
2013 Araf directly phosphorylates Smad2 in the linker region (with S253 being indispensable) in a MEK/ERK-independent manner, targeting activated Smad2 for accelerated degradation and thereby attenuating Nodal/Smad2-mediated mesendoderm induction; knockdown of araf in zebrafish increases activated Smad2, causing excess mesendoderm and dorsalization. Zebrafish araf morpholino knockdown, in vitro kinase assay (Araf phosphorylates Smad2), site-directed mutagenesis of Smad2-S253, co-immunoprecipitation, rescue experiments Nature communications High 23591895
2014 ARAF homodimerization and heterodimerization with BRAF/CRAF is induced by RAF inhibitors; ARAF homodimerization is required for its interaction with MEK1 and subsequent MEK1/ERK1/2 activation; ARAF dimer-deficient mutants cannot activate MEK1 or ERK1/2 and impair RAF-inhibitor-induced cell invasion; ARAF has an obligatory role in promoting MAPK activity and cell migration in a cell-type-dependent manner. Co-immunoprecipitation, BRET dimerization assay, purified protein competition binding assay, siRNA knockdown, 3D spheroid invasion assay, mutant ARAF expression Science signaling High 25097033
2014 hnRNP A2 regulates alternative splicing of A-Raf mRNA, reducing production of a short dominant-negative A-Raf isoform and elevating full-length A-Raf, thereby activating the Ras-MAPK-ERK pathway; knockdown of hnRNP A2 inhibits ERK1/2 activation by EGF and prevents EGF-induced A-Raf splicing switch. Splicing RT-PCR, siRNA knockdown of hnRNP A2, ERK activation assays, transformation/anchorage-independent growth assays, EGF stimulation RNA (New York, N.Y.) High 24572810
2014 Somatic ARAF mutations (compound kinase domain mutations) found in Langerhans cell histiocytosis (LCH) confer high MAP kinase kinase activity in vitro and transform mouse embryo fibroblasts; mutant ARAF activity is inhibited by the BRAF inhibitor vemurafenib. In vitro MEK kinase assay with purified mutant ARAF, MEF transformation assay, vemurafenib inhibition assay Blood High 24652991
2014 ARAF S214C mutation (found in lung adenocarcinoma) transforms immortalized human airway epithelial cells in a sorafenib-sensitive manner, demonstrating oncogenic driver function; mutations at S214 and in the related RAF1 residue are present in ~1% of lung adenocarcinomas. Retroviral transformation assay in immortalized human airway epithelial cells, sorafenib sensitivity assay, whole-genome and RNA sequencing The Journal of clinical investigation High 24569458
2016 A-Raf subcellular localization regulates its apoptotic function: in proliferating and tumor cells A-Raf localizes to mitochondria, where it sequesters MST2 and inhibits apoptosis; upon differentiation A-Raf relocalizes to the plasma membrane (regulated by downregulation of KSR2), releasing MST2 and sensitizing cells to apoptosis; siRNA knockdown of KSR2 is sufficient to relocalize A-Raf to the plasma membrane. Confocal microscopy/immunofluorescence, subcellular fractionation, siRNA knockdown of KSR2, apoptosis assays, co-immunoprecipitation of A-Raf:MST2 complex, MCF7 differentiation model Cell death and differentiation High 26891695
2017 Alternative polyadenylation (APA) of Araf mRNA switches Araf protein isoforms during microglia activation, impacting production of downstream inflammatory cytokines; cTag-PAPERCLIP identified cell-type-specific APA of Araf in intact mouse brain tissue. cTag-PAPERCLIP (cell-type-specific APA profiling in intact tissue), Western blot for Araf isoform switching, cytokine measurement upon microglia activation Neuron Medium 28910620
2019 A recurrent gain-of-function ARAF mutation (S214P) leads to loss of a conserved phosphorylation site, elevated ERK1/2 activity, enhanced lymphangiogenic capacity, and disassembly of actin skeleton and VE-cadherin junctions; these effects are rescued by MEK inhibitor trametinib; a zebrafish model recreated the lymphatic phenotype and was rescued by MEK inhibition. Lentiviral transduction of ARAF-S214P into cells, ERK1/2 phosphorylation assay, lymphangiogenesis assay, actin/VE-cadherin immunofluorescence, zebrafish morpholino model, trametinib rescue Nature medicine High 31263281
2020 ARAF mediates resistance to the RAF dimer inhibitor belvarafenib through a dimer- and kinase activity-dependent mechanism; belvarafenib induces ARAF mutant dimers that remain active in the presence of inhibitor; ARAF mutations reduce sensitivity to a panel of type II RAF inhibitors; ARAF dimerization and kinase activity are both required for resistance. Generation of belvarafenib-resistant cell lines, circulating tumor DNA analysis, ARAF dimer-deficient and kinase-dead mutant expression, signaling assays, RAF inhibitor panel testing Nature High 33953400
2020 ARAF-mediated resistance to the BRAF/CRAF-sparing inhibitor LXH254 requires both ARAF kinase function and ARAF dimerization; loss of ARAF sensitizes RAS-mutant cells to LXH254; in cells expressing only ARAF, LXH254 causes paradoxical MAPK activation similar to dabrafenib. ARAF/BRAF/CRAF siRNA/CRISPR ablation, kinase-impaired and dimer-deficient ARAF mutant expression, signaling assays, in vivo xenograft models Clinical cancer research High 33355204
2022 ARAF activates RAS in a kinase-independent manner by binding RAS and displacing the GTPase-activating protein NF1, antagonizing NF1-mediated RAS-GTP hydrolysis; this increases RAS-GTP levels and prolongs RTK-induced ERK signaling; ARAF amplification in EGFR-mutant lung cancer is associated with acquired resistance to EGFR inhibitors, overcome by combining EGFR inhibitors with SHP2 inhibitor. Co-immunoprecipitation of ARAF-RAS and ARAF-NF1 complexes, RAS-GTP pull-down assay, kinase-dead ARAF rescue experiments, ARAF overexpression/depletion in RTK-dependent cell lines, clinical EGFR-inhibitor resistant sample analysis Molecular cell High 35613620
2022 CRAF forms increased CRAF:ARAF dimers in KRAS-mutant cells (shown by quantitative proteomics); depletion of both CRAF and ARAF rescues the CRAF-loss phenotype; kinase-dead but not dimer-defective CRAF rescues growth inhibition in KRAS-mutant tumors, indicating CRAF dimerization (including with ARAF) rather than CRAF kinase activity is required for KRAS-driven tumor growth. CRISPR/siRNA depletion, quantitative proteomics of RAF dimers, kinase-dead and dimer-defective CRAF rescue experiments, KRAS-mutant tumor xenografts Cell reports High 35139374
2022 ARAF suppresses ERBB3 expression in a kinase-independent manner by inhibiting the ERBB3 promoter via the transcription factor KLF5; loss of ARAF increases ERBB3-AKT signaling and promotes metastasis; reconstitution of ARAF reverses ERBB3-AKT hyperactivation; ARAF also suppresses hNRG1-mediated AKT activation through ERBB3. siRNA/CRISPR depletion of ARAF, ERBB3 promoter reporter assay, kinase-dead ARAF rescue, anchorage-independent growth and metastasis assays, AKT/pAKT Western blot Science advances High 35302851
2003 Trihydrophobin 1 (TH1) specifically binds A-Raf (but not B-Raf or C-Raf) both in vitro and in vivo, colocalizes with A-Raf, and inhibits A-Raf kinase activity; the interaction is partially dependent on A-Raf kinase activity; TH1 co-expression causes G0/G1 cell cycle arrest. Co-immunoprecipitation, in vitro binding, confocal colocalization, Raf kinase assay, flow cytometry cell cycle analysis, isoform specificity testing The Journal of biological chemistry Medium 14684750
2004 A-Raf associates with activated EGF receptor complexes and with PDGF receptor (PDGFR) complexes independent of prior PDGF treatment; partially activated A-Raf mutant reduces tyrosine phosphorylation of PDGFR specifically at Y857 and Y1021 (PLCγ1 binding site) but not other signaling protein binding sites, thereby altering PLCγ1 and PI3K activation. Co-immunoprecipitation of A-Raf with EGF-R and PDGFR, site-specific PDGFR phosphorylation analysis by Western blot, activated A-Raf mutant expression Cellular signalling Medium 15763428
2005 A-Raf and B-Raf bind phosphoinositide lipids; A-Raf specifically binds PI(4,5)P2, PI(3,4)P2, and PA in addition to monophosphorylated PIs, while Raf-1 does not; PI(4,5)P2 binding is localized to basic residues K50 and R52 within the Ras binding domain of A-Raf; a second A-Raf lipid-binding region exists between residues 200–606. Lipid strip/overlay assay, mutagenesis of K50/R52, deletion mutant analysis, direct lipid binding assays Biochemistry Medium 15736953
2018 ARAF mediates EIF5A1-regulated trophoblast migration and invasion; hypusinated EIF5A1 controls translation of ARAF, which in turn activates integrin/ERK signaling to promote migration and invasion; ARAF knockdown phenocopies EIF5A1 loss in impairing trophoblast invasion. siRNA knockdown of EIF5A1 and ARAF, EIF5A1 mutant (K50A) expression, migration/invasion assays, ERK/integrin signaling Western blot, villous explant culture Cell death & disease Medium 30206208

Source papers

Stage 0 corpus · 100 papers · ranked by NIH iCite citations
Year Title Journal Citations PMID
2010 Clinical efficacy of a RAF inhibitor needs broad target blockade in BRAF-mutant melanoma. Nature 1429 20823850
2010 Acquired resistance to BRAF inhibitors mediated by a RAF kinase switch in melanoma can be overcome by cotargeting MEK and IGF-1R/PI3K. Cancer cell 1026 21156289
2009 A Raf-like MAPKKK gene DSM1 mediates drought resistance through reactive oxygen species scavenging in rice. Plant physiology 243 20007444
2015 Massive parallel sequencing uncovers actionable FGFR2-PPHLN1 fusion and ARAF mutations in intrahepatic cholangiocarcinoma. Nature communications 240 25608663
2003 Mutation analysis of the BRAF, ARAF and RAF-1 genes in human colorectal adenocarcinomas. Carcinogenesis 226 14688025
2011 A Raf-induced allosteric transition of KSR stimulates phosphorylation of MEK. Nature 210 21441910
2020 A RAF-SnRK2 kinase cascade mediates early osmotic stress signaling in higher plants. Nature communications 201 32001690
1995 Conditionally oncogenic forms of the A-Raf and B-Raf protein kinases display different biological and biochemical properties in NIH 3T3 cells. Molecular and cellular biology 198 7565795
2019 ARAF recurrent mutation causes central conducting lymphatic anomaly treatable with a MEK inhibitor. Nature medicine 159 31263281
1987 The complete coding sequence of the human A-raf-1 oncogene and transforming activity of a human A-raf carrying retrovirus. Nucleic acids research 149 3029685
1998 CNK, a RAF-binding multidomain protein required for RAS signaling. Cell 148 9814705
1995 Hypertrophic agonists stimulate the activities of the protein kinases c-Raf and A-Raf in cultured ventricular myocytes. The Journal of biological chemistry 143 7592840
1985 Rapid induction of hemopoietic neoplasms in newborn mice by a raf(mil)/myc recombinant murine retrovirus. Journal of virology 143 4009794
2014 Somatic activating ARAF mutations in Langerhans cell histiocytosis. Blood 140 24652991
2001 Nicotinic receptor-mediated activation by the tobacco-specific nitrosamine NNK of a Raf-1/MAP kinase pathway, resulting in phosphorylation of c-myc in human small cell lung carcinoma cells and pulmonary neuroendocrine cells. Journal of cancer research and clinical oncology 132 11768610
1996 Hepatitis B virus pX activates NF-kappa B-dependent transcription through a Raf-independent pathway. Journal of virology 129 8523586
1996 Post-natal lethality and neurological and gastrointestinal defects in mice with targeted disruption of the A-Raf protein kinase gene. Current biology : CB 125 8805280
1986 Characterization of murine A-raf, a new oncogene related to the v-raf oncogene. Molecular and cellular biology 114 3491291
2011 Increased leaf angle1, a Raf-like MAPKKK that interacts with a nuclear protein family, regulates mechanical tissue formation in the Lamina joint of rice. The Plant cell 112 22207574
1996 Selective activation of MEK1 but not MEK2 by A-Raf from epidermal growth factor-stimulated Hela cells. The Journal of biological chemistry 107 8621729
1988 In vitro-derived leukemic erythroid cell lines induced by a raf- and myc-containing retrovirus differentiate in response to erythropoietin. Proceedings of the National Academy of Sciences of the United States of America 105 2847163
2021 ARAF mutations confer resistance to the RAF inhibitor belvarafenib in melanoma. Nature 103 33953400
2014 Paradoxical activation of T cells via augmented ERK signaling mediated by a RAF inhibitor. Cancer immunology research 100 24416731
2004 A Raf/MEK/ERK signaling pathway is required for development of the sea urchin embryo micromere lineage through phosphorylation of the transcription factor Ets. Development (Cambridge, England) 100 14973284
1997 A raf-independent epidermal growth factor receptor autocrine loop is necessary for Ras transformation of rat intestinal epithelial cells. The Journal of biological chemistry 100 9228072
2014 Oncogenic and sorafenib-sensitive ARAF mutations in lung adenocarcinoma. The Journal of clinical investigation 99 24569458
2014 Splicing factor hnRNP A2 activates the Ras-MAPK-ERK pathway by controlling A-Raf splicing in hepatocellular carcinoma development. RNA (New York, N.Y.) 88 24572810
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