scholarly journals Interactome Analysis Reveals Regulator of G Protein Signaling 14 (RGS14) is a Novel Calmodulin (CaM) Effector in Mouse Brain

2018 ◽  
Author(s):  
Paul R. Evans ◽  
Kyle J. Gerber ◽  
Eric B. Dammer ◽  
Duc M. Duong ◽  
Devrishi Goswami ◽  
...  
Keyword(s):  
Protein Kinase ◽  
G Protein ◽  
Mouse Brain ◽  
Mapk Signaling ◽  
Mitogen Activated Protein Kinase ◽  
Scaffolding Protein ◽  
Actin Binding ◽  
G Protein Signaling ◽  
Dependent Manner ◽  
Protein Signaling

AbstractRegulator of G Protein Signaling 14 (RGS14) is a complex scaffolding protein with an unusual domain structure that allows it to integrate G protein and mitogen-activated protein kinase (MAPK) signaling pathways. RGS14 mRNA and protein are enriched in brain tissue of rodents and primates. In the adult mouse brain, RGS14 is predominantly expressed in postsynaptic dendrites and spines of hippocampal CA2 pyramidal neurons where it naturally inhibits synaptic plasticity and hippocampus-dependent learning and memory. However, the signaling proteins that RGS14 natively interacts with in neurons to regulate plasticity are unknown. Here, we show that RGS14 exists as a component of a high molecular weight protein complex in brain. To identify RGS14 neuronal interacting partners, endogenous RGS14 immunoprecipitated from mouse brain was subjected to mass spectrometry and proteomic analysis. We find that RGS14 interacts with key postsynaptic proteins that regulate neuronal plasticity. Gene ontology analysis reveals that the most enriched RGS14 interacting proteins have functional roles in actin-binding, calmodulin(CaM)-binding, and CaM-dependent protein kinase (CaMK) activity. We validate these proteomics findings using biochemical assays that identify interactions between RGS14 and two previously unknown binding partners: CaM and CaMKII. We report that RGS14 directly interacts with CaM in a calcium-dependent manner and is phosphorylated by CaMKII in vitro. Lastly, we detect that RGS14 associates with CaMKII and with CaM in hippocampal CA2 neurons by proximity ligation assays in mouse brain sections. Taken together, these findings demonstrate that RGS14 is a novel CaM effector and CaMKII phosphorylation substrate thereby providing new insight into cellular mechanisms by which RGS14 controls plasticity in CA2 neurons.

scholarly journals A Regulator of G Protein Signaling-containing Kinase Is Important for Chemotaxis and Multicellular Development inDictyostelium

2003 ◽  
Vol 14 (4) ◽  
pp. 1727-1743 ◽  
Author(s):  
Binggang Sun ◽  
Richard A. Firtel
Keyword(s):  
Protein Kinase ◽  
G Protein ◽  
Kinase Activity ◽  
Site Directed Mutagenesis ◽  
Membrane Localization ◽  
Pleckstrin Homology Domain ◽  
G Protein Signaling ◽  
Protein Signaling ◽  
Wild Type ◽  
Gene Encoding

We have identified a gene encoding RGS domain-containing protein kinase (RCK1), a novel regulator of G protein signaling domain-containing protein kinase. RCK1 mutant strains exhibit strong aggregation and chemotaxis defects. rck1 null cells chemotax ∼50% faster than wild-type cells, suggesting RCK1 plays a negative regulatory role in chemotaxis. Consistent with this finding, overexpression of wild-type RCK1 reduces chemotaxis speed by ∼40%. On cAMP stimulation, RCK1 transiently translocates to the membrane/cortex region with membrane localization peaking at ∼10 s, similar to the kinetics of membrane localization of the pleckstrin homology domain-containing proteins CRAC, Akt/PKB, and PhdA. RCK1 kinase activity also increases dramatically. The RCK1 kinase activity does not rapidly adapt, but decreases after the cAMP stimulus is removed. This is particularly novel considering that most other chemoattractant-activated kinases (e.g., Akt/PKB, ERK1, ERK2, and PAKa) rapidly adapt after activation. Using site-directed mutagenesis, we further show that both the RGS and kinase domains are required for RCK1 function and that RCK1 kinase activity is required for the delocalization of RCK1 from the plasma membrane. Genetic evidence suggests RCK1 function lies downstream from Gα2, the heterotrimeric G protein that couples to the cAMP chemoattractant receptors. We suggest that RCK1 might be part of an adaptation pathway that regulates aspects of chemotaxis in Dictyostelium.

scholarly journals Platyphyllenone Induces Autophagy and Apoptosis by Modulating the AKT and JNK Mitogen-Activated Protein Kinase Pathways in Oral Cancer Cells

2021 ◽  
Vol 22 (8) ◽  
pp. 4211
Author(s):  
Yen-Tze Liu ◽  
Hsin-Yu Ho ◽  
Chia-Chieh Lin ◽  
Yi-Ching Chuang ◽  
Yu-Sheng Lo ◽  
...  
Keyword(s):  
Protein Kinase ◽  
Oral Cancer ◽  
Protein Expression ◽  
Caspase 3 ◽  
Therapeutic Option ◽  
Mapk Signaling ◽  
Mitogen Activated Protein Kinase ◽  
Dependent Manner ◽  
Cancer Proliferation ◽  
Mitogen Activated Protein

Platyphyllenone is a type of diarylheptanoid that exhibits anti-inflammatory and chemoprotective effects. However, its effect on oral cancer remains unclear. In this study, we investigated whether platyphyllenone can promote apoptosis and autophagy in SCC-9 and SCC-47 cells. We found that it dose-dependently promoted the cleavage of PARP; caspase-3, -8, and -9 protein expression; and also led to cell cycle arrest at the G2/M phase. Platyphyllenone up-regulated LC3-II and p62 protein expression in both SCC-9 and SCC-47 cell lines, implying that it can induce autophagy. Furthermore, the results demonstrated that platyphyllenone significantly decreased p-AKT and increased p-JNK1/2 mitogen-activated protein kinase (MAPK) signaling pathway in a dose-dependent manner. The specific inhibitors of p-JNK1/2 also reduced platyphyllenone-induced cleavage of PARP, caspase-3, and caspase -8, LC3-II and p62 protein expression. These findings are the first to demonstrate that platyphyllenone can induce both autophagy and apoptosis in oral cancers, and it is expected to provide a therapeutic option as a chemopreventive agent against oral cancer proliferation.

scholarly journals Phosphothreonine Lyase Promotes p65 Degradation in a Mitogen-Activated Protein Kinase/Mitogen- and Stress-Activated Protein Kinase 1-Dependent Manner

2018 ◽  
Vol 87 (1) ◽  
Author(s):  
Mingyu Hou ◽  
Wenhui Wang ◽  
Feizi Hu ◽  
Yuanxing Zhang ◽  
Dahai Yang ◽  
...  
Keyword(s):  
Protein Kinase ◽  
Pathogenic Bacteria ◽  
Critical Role ◽  
Nuclear Factor Κb ◽  
Mapk Signaling ◽  
Mitogen Activated Protein Kinase ◽  
Dependent Manner ◽  
Content Type ◽  
Catalytic Active Site ◽  
Mitogen Activated Protein

ABSTRACT Bacterial phosphothreonine lyases have been identified to be type III secretion system (T3SS) effectors that irreversibly dephosphorylate host mitogen-activated protein kinase (MAPK) signaling to promote infection. However, the effects of phosphothreonine lyase on nuclear factor κB (NF-κB) signaling remain largely unknown. In this study, we detected significant phosphothreonine lyase-dependent p65 degradation during Edwardsiella piscicida infection in macrophages, and this degradative effect was blocked by the protease inhibitor MG132. Further analysis revealed that phosphothreonine lyase promotes the dephosphorylation and ubiquitination of p65 by inhibiting the phosphorylation of mitogen- and stress-activated protein kinase-1 (MSK1) and by inhibiting the phosphorylation of extracellular signal-related kinase 1/2 (ERK1/2), p38α, and c-Jun N-terminal kinase (JNK). Moreover, we revealed that the catalytic active site of phosphothreonine lyase plays a critical role in regulating the MAPK-MSK1-p65 signaling axis. Collectively, the mechanism described here expands our understanding of the pathogenic effector in not only regulating MAPK signaling but also regulating p65. These findings uncover a new mechanism by which pathogenic bacteria overcome host innate immunity to promote pathogenesis.

scholarly journals APPL1 mediates adiponectin-stimulated p38 MAPK activation by scaffolding the TAK1-MKK3-p38 MAPK pathway

2011 ◽  
Vol 300 (1) ◽  
pp. E103-E110 ◽  
Author(s):  
Xiaoban Xin ◽  
Lijun Zhou ◽  
Caleb M. Reyes ◽  
Feng Liu ◽  
Lily Q. Dong
Keyword(s):  
Protein Kinase ◽  
P38 Mapk ◽  
Mapk Pathway ◽  
Adaptor Protein ◽  
Mapk Signaling ◽  
Mitogen Activated Protein Kinase ◽  
Scaffolding Protein ◽  
Mapk Activation ◽  
P38 Mapk Pathway ◽  
Mitogen Activated Protein

The adaptor protein APPL1 mediates the stimulatory effect of adiponectin on p38 mitogen-activated protein kinase (MAPK) signaling, yet the underlying mechanism remains unclear. Here we show that, in C2C12 cells, overexpression or suppression of APPL1 enhanced or suppressed, respectively, adiponectin-stimulated p38 MAPK upstream kinase cascade, consisting of transforming growth factor-β-activated kinase 1 (TAK1) and mitogen-activated protein kinase kinase 3 (MKK3). In vitro affinity binding and coimmunoprecipitation experiments revealed that TAK1 and MKK3 bind to different regions of APPL1, suggesting that APPL1 functions as a scaffolding protein to facilitate adiponectin-stimulated p38 MAPK activation. Interestingly, suppressing APPL1 had no effect on TNFα-stimulated p38 MAPK phosphorylation in C2C12 myotubes, indicating that the stimulatory effect of APPL1 on p38 MAPK activation is selective. Taken together, our study demonstrated that the TAK1-MKK3 cascade mediates adiponectin signaling and uncovers a scaffolding role of APPL1 in regulating the TAK1-MKK3-p38 MAPK pathway, specifically in response to adiponectin stimulation.

181 THE POTENTIAL ROLE OF NON-GENOMIC PATHWAYS AND THEIR EFFECTS ON THE REGULATION OF CALBINDIN-D9k IN VITRO

2009 ◽  
Vol 21 (1) ◽  
pp. 189
Author(s):  
V. H. Dang ◽  
E.-B. Jeung
Keyword(s):  
Signaling Pathways ◽  
G Protein ◽  
Gh3 Cells ◽  
G Protein Signaling ◽  
Dependent Manner ◽  
Protein Signaling ◽  
Calbindin D9k ◽  
Protein Expressions ◽  
Genomic Effects

Calbindin-D9k (CaBP-9k), a cytosolic protein, is one of the members of the family of vitamin D-dependent calcium-binding proteins with high affinity for calcium. The previous in vitro studies indicated that this gene is controlled by 17β-estradiol (E2), a physiological estrogen, via both genomic (through its classical nuclear receptors) and non-genomic (through different cypoplasmic signals) mechanisms. In order to provide a better understanding in molecular events by which E2 exerts its actions in the regulation of CaBP-9k, we employed GH3 cells as an in vitro model to examine the possible non-genomic effects of E2 on the induction of CaBP-9k. GH3 cells were treated dose-dependently (10–5, 10–6, 10–7, 10–8, and 10–9 m) with E2-BSA, a membrane-impermeable E2 conjugated with BSA, for 24 h. To examine the time dependency, the cells were also exposed to a high concentration (10–6 m) of E2-BSA and harvested at various time points (5 min, 15 min, 30 min, 1 h, 3 h, 6 h, 12 h, 24 h, and 48 h). Furthermore, in order to determine the potential involvement of non-genomic signaling pathways in E2-BSA-induced expression of CaBP-9k, several inhibitors also were employed, including ICI 182 780 for membrane estrogen receptor (ER) pathway, pertussis toxin (PTX) for G protein signaling, U0126 for ERK pathway, and wortmannin for Akt pathway. The non-genomic effects of E2-BSA on the induction of CaBP-9k mRNA and protein were determined by semi-quantitative RT-PCR and Western blotting, respectively. In a dose-dependent manner, administration with E2-BSA (10–6 m) induced the highest response of CaBP-9k at transcriptional (mRNA) level, whereas protein level of CaBP-9k peaked at E2-BSA concentration (10–7 m) at 24 h. In a time course, E2-BSA (10–6 m) exposure caused a significant increase in both CaBP-9k mRNA and protein expressions as early as 15 min and peaked at 24 h. Co-treatment with ICI 182 780 and PTX completely inhibited E2-BSA-induced CaBP-9k mRNA and protein expressions. Interestingly, although co-treatments with U0126 and/or wortmannin alone failed to attenuate the effects of E2-BSA, a combination of 2 inhibitors completely reversed E2-BSA-induced CaBP-9k expressions at both transcriptional (mRNA) and translational (protein) levels, suggesting their involvement in the regulation of CaBP-9k in GH3 cells. Taken together, these results demonstrate that various signaling pathways may be involved in E2-induced regulation of CaBP-9k in which membrane ER and G protein signaling pathways play a central role in non-genomic responses. Further in vitro experiments are required to elucidate additional details of the interaction of ERK and Akt pathways in the regulation of CaBP-9k in these cells, offering a new insight into the mode of E2 action in the pituitary gland of human and wildlife.

Sign in / Sign up

Export Citation Format

Share Document