| 1998 |
MSK1 (RPS6KA5) is a nuclear serine/threonine kinase containing two kinase domains in a single polypeptide that is directly activated in vitro by ERK2 (MAPK/ERK) and SAPK2/p38, and phosphorylates CREB at Ser133 with a Km far lower than PKA, MAPKAP-K1, or MAPKAP-K2. Growth factor/phorbol ester-induced activation requires the MAPK/ERK cascade (blocked by PD 98059), while stress-induced activation requires SAPK2/p38 (blocked by SB 203580). MSK1 is localized in the nucleus of both unstimulated and stimulated cells. |
In vitro kinase assay, pharmacological inhibitor experiments in 293/HeLa/PC12/SK-N-MC cells, subcellular localization, mutagenesis |
The EMBO journal |
High |
9687510
|
| 1999 |
MSK1 is proposed as the major kinase mediating the nucleosomal response (histone H3 Ser10 and HMG-14 phosphorylation) downstream of both ERK and p38 MAPK pathways: it efficiently phosphorylates H3 and HMG-14 at physiologically relevant sites, and its activity toward these substrates is uniquely sensitive to H89 inhibition, which selectively inhibits the nucleosomal response in intact cells without affecting MAPK activation. |
In vitro kinase assay, pharmacological inhibition (H89) in intact cells, immunoblot with phospho-specific antibodies |
The EMBO journal |
Medium |
10469656
|
| 2000 |
MSK1 is required for mitogen-induced phosphorylation of CREB at Ser133 and ATF1 at Ser63 in mouse embryonic stem cells; MSK1-knockout ES cells show abolished TPA- and EGF-induced CREB/ATF1 phosphorylation while basal and PKA-driven (forskolin) phosphorylation remains intact. |
MSK1 gene-disruption (knockout) in mouse ES cells, phospho-specific immunoblotting |
FEBS letters |
High |
11018520
|
| 2001 |
MSK1 mediates UVB-induced phosphorylation of histone H3 at Ser28 in vivo; H89 (a selective MSK1 inhibitor) blocks this phosphorylation without affecting MAP kinases; MSK1 phosphorylates Ser28 on histone H3 and chromatin in vitro; dominant-negative N- or C-terminal kinase-dead MSK1 mutants block UVB-induced H3-Ser28 phosphorylation in cells. |
In vitro kinase assay, pharmacological inhibition (H89), dominant-negative MSK1 transfection, phospho-specific immunoblot |
The Journal of biological chemistry |
High |
11441012
|
| 2001 |
MSK1 phosphorylates STAT3 at Ser727 in vitro and in vivo following UVA irradiation; active MSK1 (but not ERKs or p38) directly phosphorylates STAT3 Ser727 in vitro; kinase-dead MSK1 mutants and H89 suppress UVA-induced Ser727 phosphorylation in cells. |
In vitro kinase assay, dominant-negative/kinase-dead mutant transfection, pharmacological inhibition (H89), immunoblot |
The Journal of biological chemistry |
High |
11553624
|
| 2002 |
MSK1 and MSK2 are required for stress- and mitogen-induced phosphorylation of CREB (Ser133) and ATF1 in primary mouse embryonic fibroblasts; double-knockout of MSK1 and MSK2 results in ~50% reduction in c-fos and junB transcription in response to stress stimuli but minimal reduction in response to mitogens. |
MSK1/MSK2 single and double knockout mouse-derived fibroblasts, phospho-specific immunoblotting, gene expression assays |
Molecular and cellular biology |
High |
11909979
|
| 2002 |
MSK1 phosphorylates Bad at Ser112 in vitro and is required for UVB-induced Bad Ser112 phosphorylation in vivo; cells expressing kinase-dead N- or C-terminal MSK1 mutants are defective for UVB-induced Bad phosphorylation; phosphorylation at Ser112 promotes dissociation of Bad from Bcl-XL. |
In vitro kinase assay, dominant-negative (kinase-dead) MSK1 mutant transfection, immunoblot with phospho-specific antibodies |
The Journal of biological chemistry |
High |
11983683
|
| 2003 |
MSK1 and MSK2 are the major kinases mediating mitogen- and stress-induced phosphorylation of histone H3 and HMG-14 in fibroblasts; MSK1/MSK2 double-knockout mouse embryonic fibroblasts show severely reduced or abolished H3 and HMG-14 phosphorylation; H3 acetylation is unimpaired, and immediate-early genes can still be induced but at reduced efficiency. |
MSK1/MSK2 double-knockout mice, phospho-specific immunoblotting, immediate-early gene expression assays |
The EMBO journal |
High |
12773393
|
| 2003 |
MSK1 associates with NF-κB p65 in a stimulus-dependent manner and phosphorylates p65 at Ser276 in the nucleus; this phosphorylation is required for TNF-induced NF-κB transactivation; mutational analysis identifies Ser276 as the MSK1 target on p65. |
Co-immunoprecipitation, in vitro kinase assay, site-directed mutagenesis of p65, reporter gene assays, pharmacological inhibition |
The EMBO journal |
High |
12628924
|
| 2003 |
MSK1 is required for full c-fos promoter activation and CREB phosphorylation in response to lysophosphatidic acid (LPA) in mouse ES cells, acting downstream of the ERK pathway. |
MSK1-knockout ES cells, promoter-reporter assay, phospho-specific immunoblotting |
BMC molecular biology |
Medium |
12769834
|
| 2003 |
MSK1 phosphorylates and activates the transcription factor ER81; MSK1 targets two serine residues on ER81 and enhances ER81-dependent transcription, particularly downstream of p38-MAPK. MSK1 also interacts with co-activators CBP and p300 and stimulates the transactivation domain of CBP. |
In vitro kinase assay, mutagenesis of ER81 phosphorylation sites, reporter gene assay, Co-IP with CBP/p300 |
Oncogene |
Medium |
12569367
|
| 2004 |
Crystal structure of the N-terminal kinase domain of MSK1 (1.8 Å resolution) reveals a unique inactive conformation in which the ATP-binding site is blocked by the nucleotide binding loop, stabilized by a novel three-stranded β-sheet formed by the N terminus, what would be the αB helix, and the activation loop. |
X-ray crystallography |
Structure |
High |
15274926
|
| 2004 |
MSK1 is required for TGF-β-induced transcriptional responses via the p38α/MSK1 pathway; dominant-interfering MSK1 mutants block Smad3 binding to the co-activator p300 in response to TGF-β, positioning MSK1 as a chromatin-remodeling node integrating Smad and p38 MAPK signaling. |
Dominant-interfering MSK1 mutants, p38 pharmacological inhibition, Co-IP (Smad3–p300 interaction), transcriptional reporter assays |
The Journal of biological chemistry |
Medium |
15133024
|
| 2005 |
MSK1 activity is regulated by a multi-site phosphorylation cascade: ERK1/2 or p38 phosphorylate Thr581 and Ser360, activating the C-terminal kinase domain, which autophosphorylates Ser212 (N-terminal T-loop) and Ser376 (hydrophobic motif), both essential for N-terminal kinase domain activity. Ser381 autophosphorylation also supports activity. Activation does not require PDK1, distinguishing MSK1 from RSKs. |
In vitro kinase assay, alanine-scanning mutagenesis of phosphorylation sites, mass spectrometry, activity assays in cells |
The Biochemical journal |
High |
15568999
|
| 2005 |
In the suprachiasmatic nucleus (SCN), photic stimulation activates MSK1 via a PACAP-ERK/MAPK-dependent mechanism; MSK1 Ser360 phosphorylation (required for kinase activation) is induced by light during the subjective night; activated ERK and MSK1 co-localize in SCN cell nuclei; MSK1 couples to mPeriod1 clock gene expression via a CREB-dependent mechanism. |
In vivo phospho-specific immunohistochemistry, MEK inhibitor (U0126) infusion, PACAP receptor antagonist, luciferase reporter assay |
The Journal of neuroscience |
Medium |
15930378
|
| 2007 |
MSK1 has a novel phosphorylation site at Thr700 phosphorylated by upstream kinases ERK1/2 and p38α; mutation of Thr700 increases basal MSK1 activity but dramatically reduces Thr581 phosphorylation (essential for activity), consistent with a mechanism whereby Thr700 phosphorylation relieves inhibition by a C-terminal autoinhibitory helix and induces a conformational shift that protects Thr581 from dephosphorylation. |
Precursor ion scanning mass spectrometry, site-directed mutagenesis, in vitro kinase assays, phospho-specific immunoblotting |
The Biochemical journal |
High |
17117922
|
| 2007 |
MSK1 is the major kinase for Ca2+-ionophore-induced Bad phosphorylation in PC12 cells and cortical neurons; siRNA knockdown of MSK1 reduces Bad phosphorylation; in contrast, knockdown of RSK2 potentiates Bad phosphorylation and elevates ERK phosphorylation, implicating RSK2 in negative-feedback regulation of ERK. |
siRNA knockdown of MSK1 or RSK2, phospho-specific immunoblotting in PC12 cells and primary cortical neurons |
Journal of neurochemistry |
Medium |
17663748
|
| 2007 |
Ca2+-stimulated adenylyl cyclase activity is absolutely required for activation of PKA, MAPK, MSK1, and CREB in hippocampal CA1 pyramidal neurons following contextual fear conditioning; MSK1 is identified as the major CREB kinase activated during training for contextual memory. |
Fear-conditioning behavioral paradigm, adenylyl cyclase knockout mice, phospho-specific immunohistochemistry |
Neuron |
Medium |
17196532
|
| 2008 |
MSK1 and MSK2 are required to limit pro-inflammatory cytokine production in macrophages stimulated with LPS by inducing transcription of the MAPK phosphatase DUSP1 and anti-inflammatory cytokine IL-10; MSK1/2 deficiency prevents binding of phosphorylated CREB and ATF1 to the DUSP1 and IL-10 gene promoters; MSK1/2 double-knockout mice are hypersensitive to LPS-induced endotoxic shock. |
MSK1/MSK2 double-knockout mice and macrophages, cytokine ELISA, chromatin immunoprecipitation (ChIP), endotoxic shock model, contact eczema model |
Nature immunology |
High |
18690222
|
| 2008 |
Glucocorticoid receptor (GR), upon ligand activation, triggers redistribution of nuclear MSK1 to the cytoplasm via a CRM1-dependent nuclear export mechanism, mediated by a direct protein-protein interaction between liganded GR and activated MSK1; this altered subcellular distribution reduces MSK1 recruitment to inflammatory gene promoters, thereby inhibiting NF-κB p65 transactivation and histone H3 phosphorylation. |
Co-immunoprecipitation (GR–MSK1 interaction), CRM1 inhibitor (leptomycin B), chromatin immunoprecipitation, subcellular fractionation |
The EMBO journal |
High |
18511904
|
| 2008 |
MSK1 phosphorylates RARα at Ser369 in the ligand-binding domain in a p38MAPK-dependent manner; this phosphorylation allows TFIIH binding and subsequent cdk7/cyclin H-mediated phosphorylation of the RARα N-terminal domain at Ser77; MSK1 also phosphorylates histone H3 at Ser10 in this context; the entire p38MAPK/MSK1-initiated cascade controls recruitment of RARα/TFIIH to response elements and target gene activation. |
In vitro kinase assay, site-directed mutagenesis of RARα phosphorylation sites, chromatin immunoprecipitation, pharmacological inhibition of p38MAPK/MSK1 |
The EMBO journal |
High |
19078967
|
| 2009 |
MSK1 mediates NF-κB p65 Ser276 phosphorylation induced by p38/ERK MAPK pathways; MSK1 knockdown by siRNA or kinase-dead MSK1 reduces RSV-induced phospho-Ser276 RelA formation; a RelA Ser276Ala mutation abolishes RSV-induced NF-κB-dependent gene expression, establishing that ROS → MSK1 → RelA-Ser276 phosphorylation is a distinct pathway from the pathway controlling RelA cytoplasmic release. |
siRNA knockdown of MSK1, pharmacological inhibition (H89), expression of RelA Ser276Ala mutant in RelA-/- MEFs, phospho-specific immunoblotting |
Journal of virology |
High |
19706715
|
| 2009 |
MSK1 is recruited to inflammatory gene promoters as part of a multi-protein complex containing 14-3-3 phospho-serine adaptor proteins and BRG1 (ATPase subunit of SWI/SNF); MSK1 is recruited by transcription factors such as Elk-1 or NF-κB; following MSK1-mediated H3 Ser10/Ser28 phosphorylation, BRG1 associates with promoters via 14-3-3 scaffolds and SWI/SNF remodels nucleosomes to enable transcription factor binding and transcription onset. |
Sequential co-immunoprecipitation, sequential chromatin immunoprecipitation (ChIP), MSK1 knockdown cells |
Nucleic acids research |
Medium |
20129940
|
| 2010 |
MSK1 phosphorylates histone H3 at the c-fos promoter in a CREB-dependent manner; in a reconstituted cell-free system, activators (SRF, Elk-1, CREB, ATF1) bound to their cognate sites recruit MSK1 to phosphorylate H3 Ser10 within chromatin; CREB plays the predominant role, and Ser133 phosphorylation of CREB is essential; the MSK1 N-terminal inhibition domain is critical for chromatin-embedded H3 phosphorylation. |
Cell-free chromatin reconstitution assay, MSK1 mutagenesis (N-terminal inhibition domain), phospho-specific analysis |
The Journal of biological chemistry |
High |
20089855
|
| 2010 |
MSK1 is required for induction of the miR-212/132 cluster in primary cortical neurons in response to BDNF; regulation occurs via the ERK1/2 pathway through both MSK-dependent and MSK-independent mechanisms, as shown using MSK1/2 knockout mice and specific inhibitors. |
MSK1/2 knockout mice, specific kinase inhibitors, deep sequencing, promoter analysis |
The Biochemical journal |
Medium |
20307261
|
| 2011 |
An acute psychological stressor induces ERK1/2 phosphorylation in dentate gyrus granule neurons within 15 min, leading to nuclear activation of MSK1 and Elk-1; MSK1 and Elk-1 then evoke H3 Ser10 phosphorylation and H3 Lys14 acetylation, resulting in c-Fos and Egr-1 induction; pERK1/2-mediated activation of MSK1 and Elk-1 requires a direct protein-protein interaction between pERK1/2 and activated glucocorticoid receptors. |
In vivo mouse stress model, co-immunoprecipitation (pERK1/2–GR interaction), phospho-specific immunohistochemistry, ChIP |
Proceedings of the National Academy of Sciences of the United States of America |
Medium |
21808001
|
| 2012 |
MSK1 is necessary for homeostatic synaptic scaling and experience-dependent synaptic plasticity; neurons from MSK1 kinase-dead knock-in mice fail to show scaling in response to activity deprivation; MSK1 forms part of a BDNF/MAPK-dependent signaling cascade that regulates cell-surface GluA1 expression via induction of Arc/Arg3.1. |
MSK1 kinase-dead knock-in mice, electrophysiology (synaptic scaling), rescue by WT MSK1 re-expression, GluA1 surface expression assay |
The Journal of neuroscience |
High |
22993422
|
| 2013 |
Downregulation of RAS-MAPK-MSK1 pathway components decreases ATXN1 levels and suppresses neurodegeneration in Drosophila and mice; pharmacological inhibition of pathway components also decreases ATXN1 levels, identifying MSK1 as a node in a genetic network that controls the abundance of the SCA1-causing protein. |
Parallel cell-based and Drosophila genetic screens, mouse SCA1 model, pharmacological inhibitors, protein level measurement |
Nature |
High |
23719381
|
| 2016 |
MSK1 (Msk1/RPS6KA5) physically interacts with the KMT2A/MLL1 lysine methyltransferase complex by co-immunoprecipitation; the majority of genes regulated by KMT2A/MLL1 knockdown respond comparably to MSK1 knockdown; KMT2A/MLL1 is required for genomic targeting of MSK1 (but not vice versa); MSK1 supports H3K4 methylation by KMT2A/MLL1 by catalyzing H3S10 and H3S28 phosphorylation. |
Co-immunoprecipitation (native and FLAG-tagged), siRNA knockdown, ChIP for H3K4me and H3S10ph at target loci |
Epigenetics & chromatin |
Medium |
27895715
|
| 2016 |
MSK1 phosphorylates β-catenin and regulates its nuclear translocation and transcriptional activity in glioblastoma cells; MSK1 is induced after PI3K/mTOR inhibitor treatment; depletion of MSK1 attenuates resistance to PI3K/mTOR inhibitors; MSK1 inhibition plus PI3K/mTOR inhibition synergizes to extend survival in an intracranial animal model. |
shRNA-mediated MSK1 depletion, phospho-specific immunoblotting of β-catenin Ser552, nuclear fractionation, intracranial mouse model |
Molecular cancer therapeutics |
Medium |
27196759
|
| 2018 |
MSK1 controls expression of luminal differentiation genes GATA3 and FOXA1 by modulating their promoter chromatin status (H3 phosphorylation); MSK1 downregulation impairs breast cancer cell differentiation, increasing bone homing and growth capacities; in vivo genome-wide shRNA screen identified MSK1 as a regulator of metastatic dormancy. |
In vivo genome-wide shRNA screen, MSK1 knockdown/overexpression, ChIP for histone modifications at GATA3/FOXA1 promoters, in vivo bone metastasis model |
Nature cell biology |
High |
29358704
|
| 2019 |
MSK1 is a downstream target of both early and late ERK activation following DNA damage; early ERK→MSK1 activation (mediated by EGFR) promotes cell survival and DNA repair; late ERK→MSK1 activation (requiring PKCδ) drives apoptosis via a nuclear PKCδ→ERK→MSK1 signaling module; both ERK and MSK1 activations are required for apoptosis in the late phase. |
shRNA-mediated depletion of MSK1, PKCδ, and EGFR; pharmacological inhibitors (MEK/ERK, EGFR); phospho-specific immunoblotting; in vivo irradiation model |
The Journal of biological chemistry |
Medium |
30679314
|
| 2020 |
STAT3 aberrantly transactivates MSK1 gene expression, and MSK1 in turn phosphorylates H3S10 and STAT3 itself; STAT3 forms a functional complex with MSK1 at the NFATc2 promoter to promote its transcription in an H3S10 phosphorylation-dependent manner, creating a positive STAT3-MSK1 feedback loop in gastric carcinogenesis. |
Co-immunoprecipitation (STAT3–MSK1 complex), ChIP at NFATc2 promoter, MSK1 knockdown/overexpression, xenograft tumor model, phospho-specific immunoblotting |
Oncogenesis |
Medium |
32041943
|
| 2023 |
MSK1 is transcriptionally activated by HOXC6 in pancreatic ductal adenocarcinoma; MSK1 phosphorylates DDX17 to suppress apoptosis; pharmacological inhibition of MSK1 combined with mTOR inhibition potently suppresses PDAC tumor growth and metastasis in mouse models. |
ChIP (HOXC6 at MSK1 promoter), siRNA/shRNA knockdown, phospho-specific identification of DDX17 as MSK1 substrate, in vivo PDAC mouse models, pharmacological inhibition |
Cell reports. Medicine |
Medium |
37951219
|
| 2017 |
MSK1 regulates BDNF-induced Arc/Arg3.1 expression via phosphorylation of histone H3 at the Arc/Arg3.1 promoter, acting downstream of ERK1/2; however, CREB Ser133 phosphorylation by MSK1 is not required for BDNF-induced Arc/Arg3.1 transcription, as a Ser133Ala CREB knock-in had no effect on induction. |
MSK1 kinase-dead knock-in mice, ChIP for H3 phosphorylation at Arc promoter, CREB Ser133Ala knock-in mice, pharmacological inhibitors |
FEBS open bio |
Medium |
28593137
|
| 2009 |
Glucocorticoid-activated GR physically interacts with activated MSK1 (Co-IP) and drives CRM1-dependent nuclear export of MSK1; this redistribution prevents recruitment of activated MSK1 to inflammatory gene promoters (ChIP), resulting in reduced NF-κB p65 transactivation and histone H3 phosphorylation. |
Co-immunoprecipitation, CRM1 inhibitor (leptomycin B), ChIP, subcellular fractionation |
The EMBO journal |
High |
18511904
|
| 2005 |
In NIH 3T3 cells, cAMP/forskolin activates p38 in a PKA-dependent fashion; p38 then activates CREB-mediated transcription via MSK1, as shown using dominant-negative MSK1 mutants and H89, but not dominant-negative MSK2 or MAPKAPK2. |
Dominant-negative mutant transfection, pharmacological inhibitors, reporter gene assays |
Cellular signalling |
Medium |
16125054
|
| 2009 |
MSK1 is required for TLR-mediated induction of IL-1ra mRNA and protein from both proximal and distal promoters in macrophages; this occurs via p38 and ERK1/2 MAPK cascades, through both IL-10-dependent and IL-10-independent mechanisms; MSK1/2 knockout mice show decreased IL-1ra production after LPS injection. |
MSK1/2 knockout macrophages and mice, RT-PCR/ELISA for IL-1ra, promoter-reporter assays |
The Biochemical journal |
Medium |
19922413
|
| 2005 |
MSK1 is confined to the nucleus of all expressing cell types in mouse brain (neurons and astroglia), in contrast to RSK1 which localizes to the Golgi apparatus; MSK1 is expressed at highest levels in striatal and olfactory tubercle neurons and in cerebellar Purkinje cells, with lower expression in a subset of astroglia. |
Immunohistochemistry on adult mouse brain sections |
Brain research. Molecular brain research |
Medium |
15893597
|