RyR-mediated Ca2+ release elicited by neuronal activity induces nuclear Ca2+ signals, CREB phosphorylation, and Npas4/RyR2 expression

The expression of several hippocampal genes implicated in learning and memory processes requires that Ca2+ signals generated in dendritic spines, dendrites, or the soma in response to neuronal stimulation reach the nucleus. The diffusion of Ca2+ in the cytoplasm is highly restricted, so neurons must use other mechanisms to propagate Ca2+ signals to the nucleus. Here, we present evidence showing that Ca2+ release mediated by the ryanodine receptor (RyR) channel type-2 isoform (RyR2) contributes to the generation of nuclear Ca2+ signals induced by gabazine (GBZ) addition, glutamate uncaging in the dendrites, or high-frequency field stimulation of primary hippocampal neurons. Additionally, GBZ treatment significantly increased cyclic adenosine monophosphate response element binding protein (CREB) phosphorylation—a key event in synaptic plasticity and hippocampal memory—and enhanced the expression of Neuronal Per Arnt Sim domain protein 4 (Npas4) and RyR2, two central regulators of these processes. Suppression of RyR-mediated Ca2+ release with ryanodine significantly reduced the increase in CREB phosphorylation and the enhanced Npas4 and RyR2 expression induced by GBZ. We propose that RyR-mediated Ca2+ release induced by neuronal activity, through its contribution to the sequential generation of nuclear Ca2+ signals, CREB phosphorylation, Npas4, and RyR2 up-regulation, plays a central role in hippocampal synaptic plasticity and memory processes.

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Cyclic AMP response element-binding protein is required in excitatory neurons in the forebrain to sustain wakefulness

SLEEP ◽

10.1093/sleep/zsaa267 ◽

2020 ◽

Author(s):

Mathieu E Wimmer ◽

Rosa Cui ◽

Jennifer M Blackwell ◽

Ted Abel

Keyword(s):

Cyclic Amp ◽

Intracellular Signaling ◽

Target Genes ◽

Binding Protein ◽

Cyclic Adenosine Monophosphate ◽

Adenosine Monophosphate ◽

Response Element ◽

Creb Phosphorylation ◽

Element Binding Protein ◽

And Control

Abstract The molecular and intracellular signaling processes that control sleep and wake states remain largely unknown. A consistent observation is that the cyclic adenosine monophosphate (AMP) response element-binding protein (CREB), an activity-dependent transcription factor, is differentially activated during sleep and wakefulness. CREB is phosphorylated by the cyclic AMP/protein kinase A (cAMP/PKA) signaling pathway as well as other kinases, and phosphorylated CREB promotes the transcription of target genes. Genetic studies in flies and mice suggest that CREB signaling influences sleep/wake states by promoting and stabilizing wakefulness. However, it remains unclear where in the brain CREB is required to drive wakefulness. In rats, CREB phosphorylation increases in the cerebral cortex during wakefulness and decreases during sleep, but it is not known if this change is functionally relevant to the maintenance of wakefulness. Here, we used the Cre/lox system to conditionally delete CREB in the forebrain (FB) and in the locus coeruleus (LC), two regions known to be important for the production of arousal and wakefulness. We used polysomnography to measure sleep/wake levels and sleep architecture in conditional CREB mutant mice and control littermates. We found that FB-specific deletion of CREB decreased wakefulness and increased non-rapid eye movement sleep. Mice lacking CREB in the FB were unable to sustain normal periods of wakefulness. On the other hand, deletion of CREB from LC neurons did not change sleep/wake levels or sleep/wake architecture. Taken together, these results suggest that CREB is required in neurons within the FB but not in the LC to promote and stabilize wakefulness.

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Prolonging photoperiod promotes testosterone synthesis of Leydig cells by directly targeting local melatonin system in rooster testes

Biology of Reproduction ◽

10.1093/biolre/ioab155 ◽

2021 ◽

Author(s):

Gaoqing Xu ◽

Zhiyu Yuan ◽

Jiani Hou ◽

Jing Zhao ◽

Hongyu Liu ◽

...

Keyword(s):

Leydig Cells ◽

Molecular Mechanisms ◽

Cyclic Adenosine Monophosphate ◽

Adenosine Monophosphate ◽

Camp Response Element Binding ◽

Membrane Receptors ◽

Creb Phosphorylation ◽

Element Binding Protein ◽

Melatonin Production ◽

Testosterone Synthesis

Abstract The study investigated the effects of prolonging photoperiod on the synthesis of testosterone and melatonin in roosters, and the effect of melatonin on testosterone synthesis in rooster Leydig cells as well as its molecular mechanisms. We randomly divided one hundred and twenty 20-week-old roosters into three groups and provided 6, 12.5 and 16 h light, respectively. The results showed that prolonging photoperiod promoted testosterone synthesis, decreased melatonin production, and inhibited the expression of melatonin membrane receptors MEL1A, MEL1B, MEL1C, and aralkylamine N-acetyltransferase (AANAT) in rooster testes. Subsequently, rooster Leydig cells were isolated and treated with 0, 0.1, 1, 10, and 100 ng/mL melatonin for 36 h. The results suggested that melatonin inhibited testosterone synthesis in rooster Leydig cells, and silencing MEL1A and MEL1B relieved the inhibition of melatonin on testosterone synthesis. Additionally, melatonin reduced the intracellular cyclic adenosine monophosphate (cAMP) level and the phosphorylation level of cAMP-response element binding protein (CREB), and CREB overexpression alleviated the inhibition of melatonin on testosterone synthesis. Furthermore, pretreatment with cAMP activator forskolin or protein kinase A (PKA) activator 8-bromo-cAMP blocked the inhibition of melatonin on CREB phosphorylation and testosterone synthesis. These results indicated that prolonging photoperiod promoted testosterone synthesis associated with the decrease in melatonin production and membrane receptors and biosynthetic enzyme of melatonin in rooster testes, and melatonin inhibited testosterone synthesis of rooster Leydig cells by inhibiting the cAMP/PKA/CREB pathway via MEL1A and MEL1B. This may be evidence that prolonging photoperiod could promote testosterone synthesis through the inhibition of the local melatonin pathway in rooster testes.

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A Novel Cell-Based Assay for G-Protein-Coupled Receptor-Mediated Cyclic Adenosine Monophosphate Response Element Binding Protein Phosphorylation

CrossRef Listing of Deleted DOIs ◽

10.1177/1087057106286608 ◽

2006 ◽

Vol 11 (4) ◽

pp. 351-358 ◽

Cited By ~ 18

Author(s):

Julie V. Selkirk ◽

Lisa M. Nottebaum ◽

Ian C. Ford ◽

Mark Santos ◽

Siobhan Malany ◽

...

Keyword(s):

G Protein ◽

Binding Protein ◽

Expression System ◽

Cyclic Adenosine Monophosphate ◽

Adenosine Monophosphate ◽

G Protein Coupled Receptor ◽

Response Element ◽

Creb Phosphorylation ◽

Element Binding Protein ◽

G Protein Coupled

Currently, the most popular means of assessing functional activity of Gs/olf-coupled receptors is via the measurement of intracellular cyclic adenosine monophosphate (cAMP) accumulation. An additional readout is the downstream phosphorylation of cAMP response element binding protein (CREB), which gives an indication of gene transcription, the ultimate response of many G-protein-coupled receptor (GPCR) signals. Current methods of quantifying CREB phosphorylation are low throughput, and so we have designed a novel higher throughput method using the Odyssey™ infrared imaging system. Functional potencies of both agonists and antagonists correlate well with radioligand binding affinities determined using examples of both an endogenous (adenosine2A receptor in PC-12 cells) and a heterologous (human melanocortin 4 receptor in HEK-293 cells) expression system. For example, the antagonist ZM241385 demonstrates 0.23 ± 0.03 nM affinity for the A2A receptor and has a functional potency of 0.26 ± 0.04 nM determined using cAMP and 0.15 ± 0.06 nM using CREB phosphorylation. These data demonstrate that this novel approach for the measurement of CREB phosphorylation is a useful tool for the assessment of GPCR activity in whole cells and is more amenable to the throughput required for the purposes of drug discovery.

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Phosphorylation of Cyclic Adenosine Monophosphate Response Element Binding Protein in Oligodendrocytes in the Corpus Callosum after Focal Cerebral Ischemia in the Rat

Journal of Cerebral Blood Flow & Metabolism ◽

10.1097/00004647-200110000-00006 ◽

2001 ◽

Vol 21 (10) ◽

pp. 1177-1188 ◽

Cited By ~ 21

Author(s):

Kortaro Tanaka ◽

Shigeru Nogawa ◽

Daisuke Ito ◽

Shigeaki Suzuki ◽

Tomohisa Dembo ◽

...

Keyword(s):

Cerebral Ischemia ◽

Corpus Callosum ◽

Focal Cerebral Ischemia ◽

Cyclic Adenosine Monophosphate ◽

Adenosine Monophosphate ◽

Medial Region ◽

Response Element ◽

Creb Phosphorylation ◽

Element Binding Protein ◽

Phosphorylated Creb

Phosphorylation of cyclic adenosine monophosphate (AMP) response element binding protein (CREB) was examined immunohistochemically in the corpus callosum of the rat brain at various time points after 90-minute focal cerebral ischemia. Focal ischemia was induced by occlusion of the middle cerebral artery (MCA) using the intraluminal suture method. Sham animals showed that numerous oligodendrocytes (OLGs) constitutively express unphosphorylated CREB. Local cerebral blood flow (lCBF) measured by the14 C-iodoantipyrine method was reduced from 44.2 ± 15.4 (mL 100 g−1 min−1) to 18.4 ± 3.8 and from 53.9 ± 14.4 to 4.8 ± 4.5 in the medial and the lateral regions of the corpus callosum, respectively, during MCA occlusion (MCAO). After release of the MCAO, lCBF recovered to the control level in each region. The medial region of the corpus callosum showed a marked increase in phosphorylated CREB-positive OLGs at 3.5 hours of recirculation, and it remained increased until 2 weeks of recirculation as it gradually declined. The activation of CREB phosphorylation in the OLGs was accompanied by expression of antiapoptotic protein bcl-2, normal staining with cresyl violet, and negative TUNEL (terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate nick-end labeling) staining. Myelination detected by immunostaining with anti-myelin basic protein (MBP) antibody and anti-myelin associated glycoprotein (MAG) antibody remained normal in the medial region of the corpus callosum. The lateral region of the corpus callosum showed a significant but only transient increase in phosphorylated CREB-positive OLGs at 3.5 hours of recirculation, which was followed by a rapid decrease during the subsequent recirculation period. Expression of bcl-2 was suppressed in this region, and demyelination became apparent. These findings suggest that signal transduction through CREB phosphorylation may be closely associated with survival of OLGs and maintenance of myelination in the corpus callosum after cerebral ischemia.

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Ceramide and Cyclic Adenosine Monophosphate (cAMP) Induce cAMP Response Element Binding Protein Phosphorylation via Distinct Signaling Pathways While Having Opposite Effects on Myeloid Cell Survival

Blood ◽

10.1182/blood.v93.1.217 ◽

1999 ◽

Vol 93 (1) ◽

pp. 217-225 ◽

Cited By ~ 36

Author(s):

Michael P. Scheid ◽

Ian N. Foltz ◽

Peter R. Young ◽

John W. Schrader ◽

Vincent Duronio

Keyword(s):

P38 Mapk ◽

Binding Protein ◽

Cyclic Adenosine Monophosphate ◽

Adenosine Monophosphate ◽

Camp Response Element Binding ◽

Camp Response Element ◽

Response Element ◽

Creb Phosphorylation ◽

Element Binding Protein ◽

Induced Apoptosis

Abstract The role of ceramide as a second messenger is a subject of great interest, particularly since it is implicated in signaling in response to inflammatory cytokines. Ceramide induces apoptosis in both cytokine-dependent MC/9 cells and factor-independent U937 cells. Elevation of cyclic adenosine monophosphate (cAMP) levels inhibits apoptosis induced by ceramide and several other treatments. One target of cAMP-mediated signaling is the transcription factor CREB (cAMP response element binding protein), and recently CREB phosphorylation at an activating site has been shown to also be mediated by a cascade involving p38 mitogen-activated protein kinase (MAPK), one of the stress-activated MAP kinases. Because no role for p38 MAPK in apoptosis has been firmly established, we examined the relationship between p38 MAPK and CREB phosphorylation under various conditions. Ceramide, or sphingomyelinase, like tumor necrosis factor- (TNF-) or the hematopoietic growth factor, interleukin-3 (IL-3), was shown to activate p38 MAPK, which in turn activated MAPKAP kinase-2. Each of these treatments led to phosphorylation of CREB (and the related factor ATF-1). A selective p38 MAPK inhibitor, SB203580, blocked TNF-– or ceramide-induced CREB phosphorylation, but had no effect on the induction of apoptosis mediated by these agents. The protective agents cAMP and IL-3 also led to CREB phosphorylation, but this effect was independent of p38 MAPK, even though IL-3 was shown to activate both p38 MAPK and MAPKAP kinase-2. Therefore, the opposing effects on apoptosis observed with cAMP and IL-3, compared with ceramide and TNF-, could not be explained on the basis of phosphorylation of CREB. In addition, because SB203580 had no effect of TNF- or ceramide-induced apoptosis, our results strongly argue against a role for p38 MAPK in the induction of TNF-– or ceramide-induced apoptosis.

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Ceramide and Cyclic Adenosine Monophosphate (cAMP) Induce cAMP Response Element Binding Protein Phosphorylation via Distinct Signaling Pathways While Having Opposite Effects on Myeloid Cell Survival

Blood ◽

10.1182/blood.v93.1.217.401k16_217_225 ◽

1999 ◽

Vol 93 (1) ◽

pp. 217-225 ◽

Cited By ~ 2

Author(s):

Michael P. Scheid ◽

Ian N. Foltz ◽

Peter R. Young ◽

John W. Schrader ◽

Vincent Duronio

Keyword(s):

P38 Mapk ◽

Binding Protein ◽

Cyclic Adenosine Monophosphate ◽

Adenosine Monophosphate ◽

Camp Response Element Binding ◽

Camp Response Element ◽

Response Element ◽

Creb Phosphorylation ◽

Element Binding Protein ◽

Induced Apoptosis

The role of ceramide as a second messenger is a subject of great interest, particularly since it is implicated in signaling in response to inflammatory cytokines. Ceramide induces apoptosis in both cytokine-dependent MC/9 cells and factor-independent U937 cells. Elevation of cyclic adenosine monophosphate (cAMP) levels inhibits apoptosis induced by ceramide and several other treatments. One target of cAMP-mediated signaling is the transcription factor CREB (cAMP response element binding protein), and recently CREB phosphorylation at an activating site has been shown to also be mediated by a cascade involving p38 mitogen-activated protein kinase (MAPK), one of the stress-activated MAP kinases. Because no role for p38 MAPK in apoptosis has been firmly established, we examined the relationship between p38 MAPK and CREB phosphorylation under various conditions. Ceramide, or sphingomyelinase, like tumor necrosis factor- (TNF-) or the hematopoietic growth factor, interleukin-3 (IL-3), was shown to activate p38 MAPK, which in turn activated MAPKAP kinase-2. Each of these treatments led to phosphorylation of CREB (and the related factor ATF-1). A selective p38 MAPK inhibitor, SB203580, blocked TNF-– or ceramide-induced CREB phosphorylation, but had no effect on the induction of apoptosis mediated by these agents. The protective agents cAMP and IL-3 also led to CREB phosphorylation, but this effect was independent of p38 MAPK, even though IL-3 was shown to activate both p38 MAPK and MAPKAP kinase-2. Therefore, the opposing effects on apoptosis observed with cAMP and IL-3, compared with ceramide and TNF-, could not be explained on the basis of phosphorylation of CREB. In addition, because SB203580 had no effect of TNF- or ceramide-induced apoptosis, our results strongly argue against a role for p38 MAPK in the induction of TNF-– or ceramide-induced apoptosis.

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Genetic Approaches to the Study of Synaptic Plasticity and Memory Storage

CNS Spectrums ◽

10.1017/s1092852900018873 ◽

2003 ◽

Vol 8 (8) ◽

pp. 597-610 ◽

Cited By ~ 11

Author(s):

Ted Abel ◽

Michael P. Kaplan

Keyword(s):

Synaptic Plasticity ◽

Molecular Mechanisms ◽

Cyclic Adenosine Monophosphate ◽

Adenosine Monophosphate ◽

Memory Storage ◽

Long Term Memory ◽

Protein Signaling ◽

Term Memory ◽

Element Binding Protein

ABSTRACTLong-term memory is believed to depend on long-lasting changes in the strength of synaptic transmission known as synaptic plasticity. Understanding the molecular mechanisms of long-term synaptic plasticity is one of the principle goals of neuroscience. Among the most powerful tools being brought to bear on this question are genetically modified mice with changes in the expression or biological activity of genes thought to contribute to these processes. This article reviews how strains of mice with alterations in the cyclic adenosine monophosphate/protein kinase A/cyclic adenosine monophosphate-response element-binding protein signaling pathway have advanced our understanding of the biological basis of learning and memory.

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RhoA inhibits the hypoxia-induced apoptosis and mitochondrial dysfunction in chondrocytes via positively regulating the CREB phosphorylation

Bioscience Reports ◽

10.1042/bsr20160622 ◽

2017 ◽

Vol 37 (2) ◽

Cited By ~ 2

Author(s):

Kai Zhang ◽

Dianming Jiang

Keyword(s):

Mitochondrial Dysfunction ◽

Cyclic Adenosine Monophosphate ◽

Adenosine Monophosphate ◽

Camp Response Element Binding ◽

Apoptosis Induction ◽

Creb Phosphorylation ◽

Mitochondrial Superoxide ◽

Element Binding Protein ◽

Induced Apoptosis ◽

Mediated Reduction

Chondrocytes that are embedded within the growth plate or the intervertebral disc are sensitive to environmental stresses, such as inflammation and hypoxia. However, little is known about the molecular signalling pathways underlining the hypoxia-induced mitochondrial dysfunction and apoptosis in chondrocytes. In the present study, we firstly examined the hypoxia-induced apoptosis, mitochondrial dysfunction and the activation of cyclic adenosine monophosphate (cAMP) response element-binding protein (CREB) signalling in human chondrocyte cell line, C28/I2 and then investigated the regulatory role of RhoA, a well-recognized apoptosis suppressor, in such process, with gain-of-function strategy. Our results indicated that hypoxia induced apoptosis and inhibited CREB phosphprylation in chondrocytes, meanwhile, the dysfunctional mitochondria with up-regulated mitochondrial superoxide and reactive oxygen species (ROS) levels, whereas with a reduced mitochondrial membrane potential (MMP) and Complex IV activity were observed in the hypoxia-treated C28/I2 cells. However, the overexpressed RhoA blocked the hypoxia-mediated reduction in CREB phosphprylation and inhibited the apoptosis induction, along with an ameliorated mitochondrial function in the hypoxia-treated C28/I2 cells. In conclusion, the present study confirmed the reduced CREB phosphorylation, along with the apoptosis induction and mitochondrial dysfunction in the hypoxia-treated chondrocyte cells. And the overexpression of RhoA ameliorated the hypoxia-induced mitochondrial dysfunction and apoptosis via blocking the hypoxia-mediated reduction in CREB phosphorylation.

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