Dataset Information

Mitogen- and stress-activated protein kinase-1 (MSK1) is directly activated by MAPK and SAPK2/p38, and may mediate activation of CREB.

ABSTRACT: We have identified a novel mitogen- and stress-activated protein kinase (MSK1) that contains two protein kinase domains in a single polypeptide. MSK1 is activated in vitro by MAPK2/ERK2 or SAPK2/p38. Endogenous MSK1 is activated in 293 cells by either growth factor/phorbol ester stimulation, or by exposure to UV radiation, and oxidative and chemical stress. The activation of MSK1 by growth factors/phorbol esters is prevented by PD 98059, which suppresses activation of the MAPK cascade, while the activation of MSK1 by stress stimuli is prevented by SB 203580, a specific inhibitor of SAPK2/p38. In HeLa, PC12 and SK-N-MC cells, PD 98059 and SB 203580 are both required to suppress the activation of MSK1 by TNF, NGF and FGF, respectively, because these agonists activate both the MAPK/ERK and SAPK2/p38 cascades. MSK1 is localized in the nucleus of unstimulated or stimulated cells, and phosphorylates CREB at Ser133 with a Km value far lower than PKA, MAPKAP-K1(p90Rsk) and MAPKAP-K2. The effects of SB 203580, PD 98059 and Ro 318220 on agonist-induced activation of CREB and ATF1 in four cell-lines mirror the effects of these inhibitors on MSK1 activation, and exclude a role for MAPKAP-K1 and MAPKAP-K2/3 in this process. These findings, together with other observations, suggest that MSK1 may mediate the growth-factor and stress-induced activation of CREB.

SUBMITTER: Deak M

PROVIDER: S-EPMC1170775 | biostudies-other | 1998 Aug

REPOSITORIES: biostudies-other

ACCESS DATA

Publications

Mitogen- and stress-activated protein kinase-1 (MSK1) is directly activated by MAPK and SAPK2/p38, and may mediate activation of CREB.

Deak M M Clifton A D AD Lucocq L M LM Alessi D R DR

The EMBO journal 19980801 15

We have identified a novel mitogen- and stress-activated protein kinase (MSK1) that contains two protein kinase domains in a single polypeptide. MSK1 is activated in vitro by MAPK2/ERK2 or SAPK2/p38. Endogenous MSK1 is activated in 293 cells by either growth factor/phorbol ester stimulation, or by exposure to UV radiation, and oxidative and chemical stress. The activation of MSK1 by growth factors/phorbol esters is prevented by PD 98059, which suppresses activation of the MAPK cascade, while the ...[more]

PMID: 9687510

Similar Datasets

Project description:Background: Melanocortin 1 receptor (MC1R), a receptor of α-melanocyte-stimulating hormone (α-MSH), is exclusively present in melanocytes where α-MSH/MC1R stimulate melanin pigmentation through microphthalmia-associated transcription factor M (MITF-M). Toll-like receptor 4 (TLR4), a receptor of endotoxin lipopolysaccharide (LPS), is distributed in immune and other cell types including melanocytes where LPS/TLR4 activate transcriptional activity of nuclear factor (NF)-κB to express cytokines in innate immunity. LPS/TLR4 also up-regulate MITF-M-target melanogenic genes in melanocytes. Here, we propose a molecular target of antimelanogenic activity through elucidating inhibitory mechanism on α-MSH-induced melanogenic programs by benzimidazole-2-butanol (BI2B), an inhibitor of LPS/TLR4-activated transcriptional activity of NF-κB. Methods: Ultraviolet B (UV-B)-irradiated skins of HRM-2 hairless mice and α-MSH-activated melanocyte cultures were employed to examine melanogenic programs. Results: Topical treatment with BI2B ameliorated UV-B-irradiated skin hyperpigmentation in mice. BI2B suppressed the protein or mRNA levels of melanogenic markers, such as tyrosinase (TYR), MITF-M and proopiomelanocortin (POMC), in UV-B-exposed and pigmented skin tissues. Moreover, BI2B inhibited melanin pigmentation in UV-B-irradiated co-cultures of keratinocyte and melanocyte cells and that in α-MSH-activated melanocyte cultures. Mechanistically, BI2B inhibited the activation of cAMP response element-binding protein (CREB) in α-MSH-induced melanogenic programs and suppressed the expression of MITF-M at the promoter level. As a molecular target, BI2B primarily inhibited mitogen-activated protein kinase (MAPK) kinase 3 (MKK3)-catalyzed kinase activity on p38MAPK. Subsequently, BI2B interrupted downstream pathway of p38MAPK-mitogen and stress-activated protein kinase-1 (MSK1)-CREB-MITF-M, and suppressed MITF-M-target melanogenic genes, encoding enzymes TYR, TYR-related protein-1 (TRP-1) and dopachrome tautomerase (DCT) in melanin biosynthesis, and encoding proteins PMEL17 and Rab27A in the transfer of pigmented melanosomes to the overlaying keratinocytes in the skin. Conclusion: Targeting the MKK3-p38MAPK-MSK1-CREB-MITF-M pathway was suggested as a rationale to inhibit UV-B- or α-MSH-induced facultative melanogenesis and as a strategy to prevent acquired pigmentary disorders in the skin.

Project description:Analysis of alterations in the hippocampus transcriptome caused by deletion of Mitogen Stress activated Kinase 1 (MSK1). MAPK signaling has been implicated in a wide range of neuronal processes, including development, plasticity and viability. One of the principal downstream targets of both the ERK/MAPK pathway and the p38 MAPK pathway is Mitogen Stress activated Kinase 1 (MSK1). Here, we sought to understand the role that MSK1 plays in neuroprotection against excitotoxic stimulation in the hippocampus. To this end, we utilized a MSK1 null mouse line, cell viability assays and array-based profiling approaches. Here we show that MSK1 is broadly expressed within the major neuronal cell layers of the hippocampus and that status epilepticus (SE) drives acute induction of MSK1 activation. In response to the SE paradigm, MSK1 KO mice exhibited a striking increase in vulnerability to pilocarpine-evoked cell death within the CA1 and CA3 cell layers. Further, cultured MSK1 null neurons exhibited a heighted level of NMDA-evoked excitotoxicity relative to WT neurons, as assessed using the LDH assay. Given these findings, we examined the hippocampal transcriptional profile of MSK1 null mice. Affymetrix array profiling revealed that with MSK1 deletion a total of 115 genes showed significant changes (> 1.25-fold) in expression. Notably, functional analysis indicated that a subset of these genes contribute to neuroprotective signaling networks. Together, these data provide important new insights into the mechanism by which the MAPK/MSK1 signaling cassette confers neuroprotection against excitotoxic insults. Approaches designed to upregulate or mimic the functional effects of MSK1 may prove beneficial against an array of degenerative processes resulting from excitotoxic insults. MAPK signaling has been implicated in a wide range of neuronal processes, including development, plasticity and viability. One of the principal downstream targets of both the ERK/MAPK pathway and the p38 MAPK pathway is Mitogen Stress activated Kinase 1 (MSK1). Here, we sought to understand the role that MSK1 plays in neuroprotection against excitotoxic stimulation in the hippocampus. To this end, we utilized a MSK1 null mouse line, cell viability assays and array-based profiling approaches. Here we show that MSK1 is broadly expressed within the major neuronal cell layers of the hippocampus and that status epilepticus (SE) drives acute induction of MSK1 activation. In response to the SE paradigm, MSK1 KO mice exhibited a striking increase in vulnerability to pilocarpine-evoked cell death within the CA1 and CA3 cell layers. Further, cultured MSK1 null neurons exhibited a heighted level of NMDA-evoked excitotoxicity relative to WT neurons, as assessed using the LDH assay. Given these findings, we examined the hippocampal transcriptional profile of MSK1 null mice. Affymetrix array profiling revealed that with MSK1 deletion a total of 115 genes showed significant changes (> 1.25-fold) in expression. Notably, functional analysis indicated that a subset of these genes contribute to neuroprotective signaling networks. Together, these data provide important new insights into the mechanism by which the MAPK/MSK1 signaling cassette confers neuroprotection against excitotoxic insults. Approaches designed to upregulate or mimic the functional effects of MSK1 may prove beneficial against an array of degenerative processes resulting from excitotoxic insults.

Dataset Information

Mitogen- and stress-activated protein kinase-1 (MSK1) is directly activated by MAPK and SAPK2/p38, and may mediate activation of CREB.

Publications

Mitogen- and stress-activated protein kinase-1 (MSK1) is directly activated by MAPK and SAPK2/p38, and may mediate activation of CREB.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets