scholarly journals Adrenergic Regulation of the Distribution of Transducer of Regulated cAMP-Response Element-Binding Protein (TORC2) in Rat Pinealocytes

Endocrinology ◽  
2011 ◽  
Vol 152 (9) ◽  
pp. 3440-3450 ◽  
Author(s):  
R. Kanyo ◽  
N. Amyotte ◽  
J. McTague ◽  
C. L. Chik ◽  
A. K. Ho
Keyword(s):  
Pineal Gland ◽  
Protein Phosphatase ◽  
Nuclear Translocation ◽  
Binding Protein ◽  
Camp Response Element Binding ◽  
Camp Response Element ◽  
Response Element ◽  
Adrenergic Antagonist ◽  
Element Binding Protein ◽  
Rat Pineal Gland

Transducers of regulated cAMP-response element-binding protein (CREB) activity (TORC) are coactivators that can increase CREB transcriptional activity, suggesting that TORC may regulate the transcription of Aanat, a CREB-target gene. In the present study, we focused on the regulation of TORC2 and its role in Aanat transcription in the rat pineal gland. Although there was no endogenous Torc2 mRNA rhythm in the rat pineal gland and treatment of cultured pinealocytes with norepinephrine (NE) had no effect on the mRNA level of Torc2, the phosphorylation state and intracellular distribution of TORC2 protein were regulated by NE. Immunoblot analysis combined with cytosolic/nuclear fractionation or phosphatase treatment showed that TORC2 protein was rapidly dephosphorylated and translocated to the nucleus after NE stimulation in rat pinealocytes. Similar dephosphorylation of TORC2 also occurred nocturnally in the rat pineal gland. The NE-mediated TORC2 dephosphorylation was blocked by cotreatment with propranolol (a β-adrenergic antagonist) but not prazosin (an α1-adrenergic antagonist) and mimicked by dibutyryl cAMP, indicating the participation of the β-adrenergic receptor/cAMP pathway. Studies with protein phosphatase inhibitors showed that only okadaic acid and calyculin A were effective in blocking the NE-mediated TORC2 dephosphorylation, suggesting the involvement of protein phosphatase 2A in this dephosphorylation. Moreover, TORC2 overexpression had an enhancing effect on NE-stimulated Aanat transcription. Together, these results indicate that NE stimulation causes nuclear translocation of TORC2 by dephosphorylating the protein through a β-adrenoceptor/cAMP mechanism and that nuclear localization of TORC2 appears to regulate Aanat transcription by NE in the rat pineal gland.

scholarly journals Involvement of Transducer of Regulated cAMP Response Element-Binding Protein Activity on Corticotropin Releasing Hormone Transcription

Endocrinology ◽  
2010 ◽  
Vol 151 (3) ◽  
pp. 1109-1118 ◽  
Author(s):  
Ying Liu ◽  
Ana G. Coello ◽  
Valery Grinevich ◽  
Greti Aguilera
Keyword(s):  
Promoter Activity ◽  
Nuclear Translocation ◽  
Binding Protein ◽  
Primary Cultures ◽  
Camp Response Element Binding ◽  
Neuronal Cultures ◽  
Dependent Manner ◽  
Camp Response Element ◽  
Response Element ◽  
Element Binding Protein

We have recently shown that phospho-cAMP response element-binding protein (CREB) is essential but not sufficient for activation of CRH transcription, suggesting the requirement of a coactivator. Here, we test the hypothesis that the CREB coactivator, transducer of regulated CREB activity (TORC), is required for activation of CRH transcription, using the cell line 4B and primary cultures of hypothalamic neurons. Immunohistochemistry and Western blot experiments in 4B cells revealed time-dependent nuclear translocation of TORC1,TORC 2, and TORC3 by forskolin [but not by the phorbol ester, phorbol 12-myristate 13-acetate (PMA)] in a concentration-dependent manner. In reporter gene assays, cotransfection of TORC1 or TORC2 potentiated the stimulatory effect of forskolin on CRH promoter activity but had no effect in cells treated with PMA. Knockout of endogenous TORC using silencing RNA markedly inhibited forskolin-activated CRH promoter activity in 4B cells, as well as the induction of endogenous CRH primary transcript by forskolin in primary neuronal cultures. Coimmunoprecipitation and chromatin immunoprecipitation experiments in 4B cells revealed association of CREB and TORC in the nucleus, and recruitment of TORC2 by the CRH promoter, after 20-min incubation with forskolin. These studies demonstrate a correlation between nuclear translocation of TORC with association to the CRH promoter and activation of CRH transcription. The data suggest that TORC is required for transcriptional activation of the CRH promoter by acting as a CREB coactivator. In addition, cytoplasmic retention of TORC during PMA treatment is likely to explain the failure of phorbolesters to activate CRH transcription in spite of efficiently phosphorylating CREB.

Scutellarin Mitigates Cancer-Induced Bone Pain by Suppressing CaMKII/CREB Pathway in Rat Models

2019 ◽  
Vol 17 (3) ◽  
pp. 249-253
Author(s):  
Liu Chenglong ◽  
Liu Haihua ◽  
Zhang Fei ◽  
Zheng Jie ◽  
Wei Fang
Keyword(s):  
Protein Kinase ◽  
Bone Pain ◽  
Binding Protein ◽  
Camp Response Element Binding ◽  
Camp Response Element ◽  
Dependent Protein Kinase ◽  
Response Element ◽  
Protein Kinase Ii ◽  
Element Binding Protein ◽  
Dependent Protein

Cancer-induced bone pain is a severe and complex pain caused by metastases to bone in cancer patients. The aim of this study was to investigate the analgesic effect of scutellarin on cancer-induced bone pain in rat models by intrathecal injection of Walker 256 carcinoma cells. Mechanical allodynia was determined by paw withdrawal threshold in response to mechanical stimulus, and thermal hyperalgesia was indicated by paw withdrawal latency in response to noxious thermal stimulus. The paw withdrawal threshold and paw withdrawal latencies were significantly decreased after inoculation of tumor cells, whereas administration of scutellarin significantly attenuated tumor cell inoculation-induced mechanical and heat hyperalgesia. Tumor cell inoculation-induced tumor growth was also significantly abrogated by scutellarin. Ca2+/calmodulin-dependent protein kinase II is a multifunctional kinase with up-regulated activity in bone pain models. The activation of Ca2+/calmodulin-dependent protein kinase II triggers phosphorylation of cAMP-response element binding protein. Scutellarin significantly reduced the expression of phosphorylated-Ca2+/calmodulin-dependent protein kinase II and phosphorylated-cAMP-response element binding protein in cancer-induced bone pain rats. Collectively, our study demonstrated that scutellarin attenuated tumor cell inoculation-induced bone pain by down-regulating the expression of phosphorylated-Ca2+/calmodulin-dependent protein kinase II and phosphorylated-cAMP-response element binding protein. The suppressive effect of scutellarin on phosphorylated-Ca2+/calmodulin-dependent protein kinase II/phosphorylated-cAMP-response element binding protein activation may serve as a novel therapeutic strategy for CIBP management.

cAMP Response Element Binding Protein Is Expressed and Phosphorylated in the Human Heart

Circulation ◽  
1995 ◽  
Vol 92 (8) ◽  
pp. 2041-2043 ◽  
Author(s):  
Frank Ulrich Müller ◽  
Peter Bokník ◽  
Andreas Horst ◽  
Jörg Knapp ◽  
Bettina Linck ◽  
...  
Keyword(s):  
Human Heart ◽  
Binding Protein ◽  
Camp Response Element Binding ◽  
Camp Response Element ◽  
Response Element ◽  
Element Binding Protein

scholarly journals p300/cAMP-response-element-binding-protein ('CREB')-binding protein (CBP) modulates co-operation between myocyte enhancer factor 2A (MEF2A) and thyroid hormone receptor-retinoid X receptor

2003 ◽  
Vol 369 (3) ◽  
pp. 477-484 ◽  
Author(s):  
Antonio De LUCA ◽  
Anna SEVERINO ◽  
Paola De PAOLIS ◽  
Giuliano COTTONE ◽  
Luca De LUCA ◽  
...  
Keyword(s):  
Thyroid Hormone ◽  
Binding Protein ◽  
Camp Response Element Binding ◽  
Creb Binding Protein ◽  
Camp Response Element ◽  
Response Element ◽  
Adenovirus E1a ◽  
Element Binding Protein ◽  
Enhancer Factor

Thyroid hormone receptors (TRs) and members of the myocyte enhancer factor 2 (MEF2) family are involved in the regulation of muscle-specific gene expression during myogenesis. Physical interaction between these two factors is required to synergistically activate gene transcription. p300/cAMP-response-element-binding-protein ('CREB')-binding protein (CBP) interacting with transcription factors is able to increase their activity on target gene promoters. We investigated the role of p300 in regulating the TR—MEF2A complex. To this end, we mapped the regions of these proteins involved in physical interactions and we evaluated the expression of a chloramphenicol acetyltransferase (CAT) reporter gene in U2OS cells under control of the α-myosin heavy chain promoter containing the thyroid hormone response element (TRE). Our results suggested a role of p300/CBP in mediating the transactivation effects of the TR—retenoid X receptor (RxR)—MEF2A complex. Our findings showed that the same C-terminal portion of p300 binds the N-terminal domains of both TR and MEF2A, and our in vivo studies demonstrated that TR, MEF2A and p300 form a ternary complex. Moreover, by the use of CAT assays, we demonstrated that adenovirus E1A inhibits activation of transcription by TR—RxR—MEF2A—p300 but not by TR—RxR—MEF2A. Our data suggested that p300 can bind and modulate the activity of TR—RxR—MEF2A at TRE. In addition, it is speculated that p300 might modulate the activity of the TR—RxR—MEF2A complex by recruiting a hypothetical endogenous inhibitor which may act like adenovirus E1A.

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