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Dopamine Reduces SARS-CoV-2 Replication In Vitro through Downregulation of D2 Receptors and Upregulation of Type-I Interferons. Cells 2022; 11:cells11101691. [PMID: 35626728 PMCID: PMC9139638 DOI: 10.3390/cells11101691] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2022] [Revised: 05/13/2022] [Accepted: 05/18/2022] [Indexed: 02/06/2023] Open
Abstract
Recent evidence suggests that SARS-CoV-2 hinders immune responses via dopamine (DA)-related mechanisms. Nonetheless, studies addressing the specific role of DA in the frame of SARS-CoV-2 infection are still missing. In the present study, we investigate the role of DA in SARS-CoV-2 replication along with potential links with innate immune pathways in CaLu-3 human epithelial lung cells. We document here for the first time that, besides DA synthetic pathways, SARS-CoV-2 alters the expression of D1 and D2 DA receptors (D1DR, D2DR), while DA administration reduces viral replication. Such an effect occurs at non-toxic, micromolar-range DA doses, which are known to induce receptor desensitization and downregulation. Indeed, the antiviral effects of DA were associated with a robust downregulation of D2DRs both at mRNA and protein levels, while the amount of D1DRs was not significantly affected. While halting SARS-CoV-2 replication, DA, similar to the D2DR agonist quinpirole, upregulates the expression of ISGs and Type-I IFNs, which goes along with the downregulation of various pro-inflammatory mediators. In turn, administration of Type-I IFNs, while dramatically reducing SARS-CoV-2 replication, converges in downregulating D2DRs expression. Besides configuring the CaLu-3 cell line as a suitable model to study SARS-CoV-2-induced alterations at the level of the DA system in the periphery, our findings disclose a previously unappreciated correlation between DA pathways and Type-I IFN response, which may be disrupted by SARS-CoV-2 for host cell invasion and replication.
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Hu H, Jiang M, Cao Y, Zhang Z, Jiang B, Tian F, Feng J, Dou Y, Gorospe M, Zheng M, Zheng L, Yang Z, Wang W. HuR regulates phospholamban expression in isoproterenol-induced cardiac remodelling. Cardiovasc Res 2020; 116:944-955. [PMID: 31373621 DOI: 10.1093/cvr/cvz205] [Citation(s) in RCA: 29] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/23/2019] [Revised: 06/30/2019] [Accepted: 08/01/2019] [Indexed: 12/29/2022] Open
Abstract
AIMS The elevated expression of phospholamban (PLB) has been observed in heart failure and cardiac remodelling, inhibiting the affinity of Ca2+ pump to Ca2+ thereby impairing heart relaxation. However, the mechanisms underlying the regulation of PLB remains to be further studied. The present study aims to test the role of RNA-binding protein HuR in the regulation of PLB and the impact of this regulatory process in cardiac remodelling. METHODS AND RESULTS A mouse model specifically deleted HuR in cardiomyocytes were used for testing the role of HuR in regulating PLB during isoproterenol (ISO)-induced cardiac remodelling. HuR deficiency did not significantly influence the phenotype and function of mouse heart under static status. However, deletion of HuR in cardiomyocytes mitigated the effect of ISO in inducing PLB expression and reducing β1-AR expression, in turn aggravating ISO-induced myocardial hypertrophy and cardiac fibrosis. In H9C2 cells, association of HuR with PLB and β1-AR mRNAs stabilized PLB mRNA and destabilized β1-AR mRNA, respectively. CONCLUSION HuR stabilizes PLB mRNA and destabilizes β1-AR mRNA. The HuR-PLB and HuR-β1-AR regulatory processes impact on ISO-induced cardiac remodelling.
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Affiliation(s)
- Han Hu
- >Department of Biochemistry and Molecular Biology, Beijing Key Laboratory of Protein Posttranslational Modifications and Cell Function, School of Basic Medical Sciences, Peking University Health Science Center, 38 Xueyuan Road, Beijing 100191, China
| | - Mingyang Jiang
- Department of Cardiology, State Key Laboratory of Pharmaceutical Biotechnology and MOE Key Laboratory of Model Animal for Disease Study, Model Animal Research Center, Nanjing Biomedical Research Institute, Nanjing University, Nanjing 210061, China
| | - Yangpo Cao
- Department of Physiology and Pathophysiology, School of Basic Medical Sciences, Peking University Health Science Center, 38 Xueyuan Road Beijing, 100191, China
| | - Zhuojun Zhang
- >Department of Biochemistry and Molecular Biology, Beijing Key Laboratory of Protein Posttranslational Modifications and Cell Function, School of Basic Medical Sciences, Peking University Health Science Center, 38 Xueyuan Road, Beijing 100191, China
| | - Bin Jiang
- >Department of Biochemistry and Molecular Biology, Beijing Key Laboratory of Protein Posttranslational Modifications and Cell Function, School of Basic Medical Sciences, Peking University Health Science Center, 38 Xueyuan Road, Beijing 100191, China
| | - Feng Tian
- Department of Laboratory Animal Science, Peking University Health Science Center, 38 Xueyuan Road, Beijing 100191, China
| | - Juan Feng
- Department of Physiology and Pathophysiology, School of Basic Medical Sciences, Peking University Health Science Center, 38 Xueyuan Road Beijing, 100191, China
| | - Yali Dou
- Department of Pathology and Biological Chemistry, University of Michigan, 1301 Catherine Street, Ann Arbor, MI 48105, USA
| | - Myriam Gorospe
- Laboratory of Genetics and Genomics, National Institute on Aging, National Institutes of Health, 251 Bayview Blvd, Baltimore, MD 21224, USA
| | - Ming Zheng
- Department of Physiology and Pathophysiology, School of Basic Medical Sciences, Peking University Health Science Center, 38 Xueyuan Road Beijing, 100191, China
| | - Lemin Zheng
- Institute of Cardiovascular Research, School of Basic Medical Sciences, Peking University Health Science Center, 38 Xueyuan Road, Beijing 100191, China
| | - Zhongzhou Yang
- Department of Cardiology, State Key Laboratory of Pharmaceutical Biotechnology and MOE Key Laboratory of Model Animal for Disease Study, Model Animal Research Center, Nanjing Biomedical Research Institute, Nanjing University, Nanjing 210061, China
| | - Wengong Wang
- >Department of Biochemistry and Molecular Biology, Beijing Key Laboratory of Protein Posttranslational Modifications and Cell Function, School of Basic Medical Sciences, Peking University Health Science Center, 38 Xueyuan Road, Beijing 100191, China
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3
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Bomberg H, Bierbach B, Flache S, Novák M, Schäfers HJ, Menger MD. Dobutamine Versus Vasopressin After Mesenteric Ischemia. J Surg Res 2019; 235:410-423. [DOI: 10.1016/j.jss.2018.10.028] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2018] [Revised: 09/15/2018] [Accepted: 10/17/2018] [Indexed: 12/26/2022]
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4
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Das M, Das S. Docosahexaenoic Acid (DHA) Induced Morphological Differentiation of Astrocytes Is Associated with Transcriptional Upregulation and Endocytosis of β 2-AR. Mol Neurobiol 2018; 56:2685-2702. [PMID: 30054857 DOI: 10.1007/s12035-018-1260-0] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2018] [Accepted: 07/17/2018] [Indexed: 12/24/2022]
Abstract
Docosahexaenoic acid (DHA), an important ω-3 fatty acid, is abundantly present in the central nervous system and is important in every step of brain development. Much of this knowledge has been based on studies of the role of DHA in the function of the neurons, and reports on its effect on the glial cells are few and far between. We have previously reported that DHA facilitates astrocyte differentiation in primary culture. We have further explored the signaling mechanism associated with this event. It was observed that a sustained activation of the extracellular signal-regulated kinase (ERK) appeared to be critical for DHA-induced differentiation of the cultured astrocytes. Prior exposure to different endocytic inhibitors blocked both ERK activation and differentiation of the astrocytes during DHA treatment suggesting that the observed induction of ERK-2 was purely endosomal. Unlike the β1-adrenergic receptor (β1-AR) antagonist, atenolol, pre-treatment of the cells with the β2-adrenergic receptor (β2-AR) antagonist, ICI-118,551 inhibited the DHA-induced differentiation process, indicating a downstream involvement of β2-AR in the differentiation process. qRT-PCR and western blot analysis demonstrated a significant induction in the mRNA and protein expression of β2-AR at 18-24 h of DHA treatment, suggesting that the induction of β2-AR may be due to transcriptional upregulation. Moreover, DHA caused activation of PKA at 6 h, followed by activation of downstream cAMP response element-binding protein, a known transcription factor for β2-AR. Altogether, the observations suggest that DHA upregulates β2-AR in astrocytes, which undergo endocytosis and signals for sustained endosomal ERK activation to drive the differentiation process.
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Affiliation(s)
- Moitreyi Das
- Neurobiology Division, Cell Biology & Physiology Department, CSIR-Indian Institute of Chemical Biology, 4 Raja S. C. Mullick Road, Jadavpur, Kolkata, 700032, India
| | - Sumantra Das
- Neurobiology Division, Cell Biology & Physiology Department, CSIR-Indian Institute of Chemical Biology, 4 Raja S. C. Mullick Road, Jadavpur, Kolkata, 700032, India.
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5
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Yin Q, Yang C, Wu J, Lu H, Zheng X, Zhang Y, Lv Z, Zheng X, Li Z. Downregulation of β-Adrenoceptors in Isoproterenol-Induced Cardiac Remodeling through HuR. PLoS One 2016; 11:e0152005. [PMID: 27035432 PMCID: PMC4818026 DOI: 10.1371/journal.pone.0152005] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2015] [Accepted: 03/06/2016] [Indexed: 12/15/2022] Open
Abstract
β-adrenergic receptors (β-ARs) play an important role in cardiac remodeling, which is the key pathological process in various heart diseases and leads to heart failure. However, the regulation of β-AR expression in remodeling hearts is still unclear. This study aims to clarify the possible mechanisms underlying the regulation of β1- and β2-AR expression in cardiac remodeling. The rat model of cardiac remodeling was established by subcutaneous injection of isoproterenol(ISO) at the dose of 0.25 mg·kg(-1)·d(-1) for 7 days. We found that the expression of β1- and β2-ARs decreased in the remodeling heart. The mechanisms may include the inhibition of DNA transcription and the increase of mRNA degradation. cAMP-response element binding protein(CREB) is a well-known transcription factor of β-AR. However, the expression and activation of CREB was not changed in the remodeling heart. Further, human Antigen-R (HuR), a RNA binding protein, which binds to the 3'-untranslated region of the β-AR mRNA and promotes RNA degradation, was increased in the remodeling model. And in vitro, HuR deficiency reversed the reduction of β-AR mRNA induced by ISO. Therefore, the present findings indicate that HuR, but not CREB, is responsible for the reduction of β-AR expression in ISO induced cardiac remodeling.
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MESH Headings
- 3' Untranslated Regions
- Animals
- Cardiomegaly/chemically induced
- Cardiomegaly/genetics
- Cardiomegaly/metabolism
- Cells, Cultured
- Down-Regulation
- ELAV-Like Protein 1/genetics
- ELAV-Like Protein 1/metabolism
- Fibrosis
- Humans
- Isoproterenol
- Myocardium/metabolism
- Myocardium/pathology
- Myocytes, Cardiac/metabolism
- Myocytes, Cardiac/pathology
- RNA Interference
- RNA Stability
- RNA, Messenger/genetics
- RNA, Messenger/metabolism
- RNA, Small Interfering/genetics
- Rats
- Rats, Sprague-Dawley
- Receptors, Adrenergic, beta-1/genetics
- Receptors, Adrenergic, beta-2/genetics
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Affiliation(s)
- Qian Yin
- Department of Cardiovascular Medicine, the First Affiliated Hospital of Xi'an Jiaotong University, Xi’an 71006, China
- Institute of Vascular Medicine, Peking University Third Hospital, Beijing Key Laboratory of Cardiovascular Receptors Research, Key Laboratory of Cardiovascular Molecular Biology and Regulatory Peptides, Ministry of Health and Key Laboratory of Molecular Cardiovascular Sciences, Ministry of Education, Beijing, 100191, China
| | - Chengzhi Yang
- Institute of Vascular Medicine, Peking University Third Hospital, Beijing Key Laboratory of Cardiovascular Receptors Research, Key Laboratory of Cardiovascular Molecular Biology and Regulatory Peptides, Ministry of Health and Key Laboratory of Molecular Cardiovascular Sciences, Ministry of Education, Beijing, 100191, China
| | - Jimin Wu
- Institute of Vascular Medicine, Peking University Third Hospital, Beijing Key Laboratory of Cardiovascular Receptors Research, Key Laboratory of Cardiovascular Molecular Biology and Regulatory Peptides, Ministry of Health and Key Laboratory of Molecular Cardiovascular Sciences, Ministry of Education, Beijing, 100191, China
| | - Haiyan Lu
- Institute of Vascular Medicine, Peking University Third Hospital, Beijing Key Laboratory of Cardiovascular Receptors Research, Key Laboratory of Cardiovascular Molecular Biology and Regulatory Peptides, Ministry of Health and Key Laboratory of Molecular Cardiovascular Sciences, Ministry of Education, Beijing, 100191, China
- Key Laboratory of Resource Biology and Biotechnology in Western China, Ministry of Education, College of Life Sciences, Northwest University, Xi’an 710069, China
| | - Xiaohui Zheng
- Key Laboratory of Resource Biology and Biotechnology in Western China, Ministry of Education, College of Life Sciences, Northwest University, Xi’an 710069, China
| | - Youyi Zhang
- Institute of Vascular Medicine, Peking University Third Hospital, Beijing Key Laboratory of Cardiovascular Receptors Research, Key Laboratory of Cardiovascular Molecular Biology and Regulatory Peptides, Ministry of Health and Key Laboratory of Molecular Cardiovascular Sciences, Ministry of Education, Beijing, 100191, China
| | - Zhizhen Lv
- Institute of Vascular Medicine, Peking University Third Hospital, Beijing Key Laboratory of Cardiovascular Receptors Research, Key Laboratory of Cardiovascular Molecular Biology and Regulatory Peptides, Ministry of Health and Key Laboratory of Molecular Cardiovascular Sciences, Ministry of Education, Beijing, 100191, China
| | - Xiaopu Zheng
- Department of Cardiovascular Medicine, the First Affiliated Hospital of Xi'an Jiaotong University, Xi’an 71006, China
| | - Zijian Li
- Institute of Vascular Medicine, Peking University Third Hospital, Beijing Key Laboratory of Cardiovascular Receptors Research, Key Laboratory of Cardiovascular Molecular Biology and Regulatory Peptides, Ministry of Health and Key Laboratory of Molecular Cardiovascular Sciences, Ministry of Education, Beijing, 100191, China
- Key laboratory of Chinese internal medicine of MOE and Beijing, Dongzhimen hospital, Beijing university of Chinese medicine, 5# Haiyuncang lane, Dongcheng district, Beijing100700, China
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Bomberg H, Bierbach B, Flache S, Scheuer C, Novák M, Schäfers HJ, Menger M. Vasopressin Induces Rectosigmoidal Mucosal Ischemia During Cardiopulmonary Bypass. J Card Surg 2013; 29:108-15. [DOI: 10.1111/jocs.12242] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- H. Bomberg
- Department of Thoracic and Cardiovascular Surgery; University Hospital of Saarland; Homburg/Saar Germany
- Department of Anesthesiology, Intensive Care Medicine and Pain Medicine; University Hospital Schleswig-Holstein; Kiel Germany
| | - B. Bierbach
- Department of Thoracic and Cardiovascular Surgery; University Hospital of Saarland; Homburg/Saar Germany
- Department of Thoracic and Cardiovascular Surgery; University Hospital Schleswig-Holstein; Kiel Germany
| | - S. Flache
- Department of Thoracic and Cardiovascular Surgery; University Hospital of Saarland; Homburg/Saar Germany
| | - C. Scheuer
- Institute for Clinical and Experimental Surgery; University Hospital of Saarland; Homburg/Saar Germany
| | - M. Novák
- Institute for Clinical and Experimental Surgery; University Hospital of Saarland; Homburg/Saar Germany
| | - H.-J. Schäfers
- Department of Thoracic and Cardiovascular Surgery; University Hospital of Saarland; Homburg/Saar Germany
| | - M.D. Menger
- Institute for Clinical and Experimental Surgery; University Hospital of Saarland; Homburg/Saar Germany
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7
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Bomberg H, Bierbach B, Flache S, Wagner I, Gläser L, Groesdonk HV, Menger MD, Schäfers HJ. Endothelin and vasopressin influence splanchnic blood flow distribution during and after cardiopulmonary bypass. J Thorac Cardiovasc Surg 2012; 145:539-47. [PMID: 22551769 DOI: 10.1016/j.jtcvs.2012.03.014] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/28/2011] [Revised: 02/13/2012] [Accepted: 03/12/2012] [Indexed: 11/28/2022]
Abstract
OBJECTIVE Gastrointestinal blood flow can be compromised during and after cardiopulmonary bypass. Endothelin has been shown to be involved in the intestinal microcirculatory disturbance of sepsis. The aim of the present study was to analyze the involvement of the endothelin system on intestinal blood flow regulation during cardiopulmonary bypass and the effect of vasopressin given during cardiopulmonary bypass. METHODS A total of 24 pigs were studied in 4 groups (n = 6): group I, sham; group II, ischemia/reperfusion with 1 hour of superior mesenteric artery occlusion; group III, cardiopulmonary bypass for 1 hour; and group IV, 1 hour of cardiopulmonary bypass plus vasopressin administration, maintaining the baseline arterial pressure. All the pigs were reperfused for 90 minutes. During the experiment, the hemodynamics and jejunal microcirculation were measured continuously. The jejunal mucosal expression of endothelin-1 and its receptor subtypes A and B were determined using polymerase chain reaction. RESULTS During cardiopulmonary bypass, superior mesenteric artery flow was preserved but marked jejunal microvascular impairment occurred compared with baseline (mucosal capillary density, 192.2 ± 5.4 vs 150.8 ± 5.1 cm/cm(2); P = .005; tissue blood flow, 501.7 ± 39.3 vs 332.3 ± 27.9 AU; P = .025). The expression of endothelin-1 after cardiopulmonary bypass (3.2 ± 0.4 vs 12.2 ± 0.8 RQ, P = .006) and endothelin subtype A (0.7 ± 0.2 vs 2.4 ± 0.6 RQ; P = .01) was significantly increased compared to the sham group. Vasopressin administration during cardiopulmonary bypass led to normal capillary density (189.9 ± 3.9 vs 178.0 ± 6.3; P = .1) and tissue blood flow (501.7 ± 39.3 vs 494.7 ± 44.4 AU; P = .4) compared with baseline. The expression of endothelin-1 (3.2 ± 0.4 vs 1.8 ± 0.3 RQ; P = .3) and endothelin subtype A (0.7 ± 0.2 vs 0.9 ± 0.2 RQ; P = .5) was not different from the sham group. CONCLUSIONS Cardiopulmonary bypass leads to microvascular impairment of jejunal microcirculation, which is associated with the upregulation of endothelin-1 and endothelin subtype A. The administration of vasopressin minimizes these cardiopulmonary bypass-associated alterations.
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Affiliation(s)
- Hagen Bomberg
- Department of Thoracic and Cardiovascular Surgery, University Hospital of Saarland, Homburg/Saar, Germany
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8
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Chen X, Fahy AL, Green AS, Anderson MJ, Rhoads RP, Limesand SW. β2-Adrenergic receptor desensitization in perirenal adipose tissue in fetuses and lambs with placental insufficiency-induced intrauterine growth restriction. J Physiol 2010; 588:3539-49. [PMID: 20643771 DOI: 10.1113/jphysiol.2010.192310] [Citation(s) in RCA: 53] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
Placental insufficiency-induced intrauterine growth restriction (IUGR) fetuses have chronic hypoxaemia and elevated plasma catecholamine concentrations. In this study, we determined whether adrenergic responsiveness becomes desensitized in the perirenal adipose tissue of IUGR fetuses and lambs by measuring adrenergic receptor (AR) mRNA and protein levels. We also tested the ability of adrenaline to mobilize non-esterified fatty acids (NEFAs) in young lambs. Perirenal adipose tissue was collected from IUGR and control fetuses at 133 days of gestational age (dGA) and lambs at 18 days of age (dA). β(2)-AR mRNA concentrations were 59% and 74% lower (P < 0.05) in IUGR fetuses and lambs compared to controls, respectively, which also resulted in lower protein levels (P < 0.05). No treatment differences were detected for α(1A)-, α(1B)-, α(1D)-, α(2A)-, α(2B)-, α(2C)-, β(1)- and β(3)-AR expression. mRNA concentrations were also determined for hormone sensitive lipase (HSL), perilipin (lipid droplet-associated protein), and two adipokines, leptin and adiponectin. Adiponectin and HSL were not different between treatments at either age. Compared to controls, perilipin and leptin mRNA concentrations were lower (P < 0.05) in IUGR fetuses but not in lambs. Because of the β(2)-AR results, we challenged a second cohort of lambs with exogenous adrenaline at 21 dA. The ability of adrenaline to mobilize NEFA was 55 ± 15% lower (P < 0.05) in IUGRs than controls. Collectively, our findings indicate that elevated catecholamine exposure in utero causes desensitization of adipose tissue by down-regulation of β(2)-AR, and this persists in lambs. This impairment in adrenergic stimulated lipolysis might partially explain early onset obesity in IUGR offspring.
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Affiliation(s)
- Xiaochuan Chen
- Department of Animal Sciences, University of Arizona, 1650 E. Limberlost Drive, Tucson, AZ 85719, USA
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Carvalho AF, Mackie K, Van Bockstaele EJ. Cannabinoid modulation of limbic forebrain noradrenergic circuitry. Eur J Neurosci 2010; 31:286-301. [PMID: 20074224 DOI: 10.1111/j.1460-9568.2009.07054.x] [Citation(s) in RCA: 50] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
Both the endocannabinoid and noradrenergic systems have been implicated in neuropsychiatric disorders. Importantly, low levels of norepinephrine are seen in patients with depression, and antagonism of the cannabinoid receptor type 1 (CB1R) is able to induce depressive symptoms in rodents and humans. Whether the interaction between the two systems is important for the regulation of these behaviors is not known. In the present study, adult male Sprague-Dawley rats were acutely or chronically administered the CB1R synthetic agonist WIN 55,212-2, and alpha2A and beta1 adrenergic receptors (AR) were quantified by Western blot. These AR have been shown to be altered in a number of psychiatric disorders and following antidepressant treatment. CB1R agonist treatment induced a differential decrease in alpha2A- and beta1-ARs in the nucleus accumbens (Acb). Moreover, to assess long-lasting changes induced by CB1R activation, some of the chronically treated rats were killed 7 days following the last injection. This revealed a persistent effect on alpha2A-AR levels. Furthermore, the localization of CB1R with respect to noradrenergic profiles was assessed in the Acb and in the nucleus of the solitary tract (NTS). Our results show a significant topographic distribution of CB1R and dopamine beta hydroxylase immunoreactivities (ir) in the Acb, with higher co-localization observed in the NTS. In the Acb, CB1R-ir was found in terminals forming either symmetric or asymmetric synapses. These results suggest that cannabinoids may modulate noradrenergic signaling in the Acb, directly by acting on noradrenergic neurons in the NTS or indirectly by modulating inhibitory and excitatory input in the Acb.
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Affiliation(s)
- Ana F Carvalho
- Neurosurgery, Farber Institute for Neurosciences, Thomas Jefferson University, Philadelphia, PA 19107, USA.
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10
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Cherry J, Jones H, Karschner VA, Pekala PH. Post-transcriptional control of CCAAT/enhancer-binding protein beta (C/EBPbeta) expression: formation of a nuclear HuR-C/EBPbeta mRNA complex determines the amount of message reaching the cytosol. J Biol Chem 2008; 283:30812-20. [PMID: 18678862 PMCID: PMC2576548 DOI: 10.1074/jbc.m805659200] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2008] [Indexed: 12/27/2022] Open
Abstract
In 3T3-L1 cells, HuR is constitutively expressed and prior to induction of differentiation localized predominantly to the nucleus. Within minutes of induction of differentiation, nuclear HuR binds to its target ligand mRNAs, and the complexes appear to move to the cytosol. One ligand mRNA is the CCAAT/enhancer-binding protein beta (C/EBPbeta) message. To examine the function and importance of the HuR-C/EBPbeta interaction, retroviral expression constructs were created in which the HuR binding site was altered by deletion (betadel) or deletion and substitution (betad/s). Expression of these constructs in murine embryonic fibroblasts resulted in significant adipose conversion relative to those cells expressing wild type C/EBPbeta. C/EBPbeta protein content was increased markedly in both betadel and betad/s, which correlated with the acquisition of the adipocyte phenotype. Analysis of the betad/s cell line demonstrated a robust expression of C/EBPalpha coincident with peroxisome proliferator-activated receptor gamma expression. Total C/EBPbeta mRNA accumulation indicated no difference between cells harboring either the wild type C/EBPbeta cDNA or betad/s construct. However, cytosolic C/EBPbeta mRNA in the cells expressing the betad/s construct was maintained at levels between 2- and 7-fold greater than in the cells expressing the wild type construct. Alteration in mRNA half-life was not responsible for the increased accumulation. Mechanistically, these data suggest that HuR binding results in nuclear retention of the C/EBPbeta mRNA and is consistent with HuR control, at least in part, of mRNA processing.
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Affiliation(s)
- Joy Cherry
- Department of Biochemistry and Molecular Biology, The Brody School of Medicine at East Carolina University, Greenville, North Carolina 27858, USA
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11
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Abstract
Excitatory NMDA receptors are an important target of ethanol. Chronic ethanol exposure, in vivo and in vitro, increases polypeptide levels of NR1 subunit, the key subunit of functional NMDA receptors. In vitro, chronic ethanol treatment increases the half-life of NR1 mRNA and this observation is dependent on new protein synthesis. The present study was undertaken to locate cis-acting region(s) within the NR1 3'-untranslated region (UTR) and identify NR1 3'-UTR binding trans-acting proteins expressed in mouse fetal cortical neurons. Utilizing RNA gel shift assays we identified a 156-nt cis-acting region that binds to polysomal trans-acting proteins. This binding was highly specific as inclusion of cyclophilin RNA or tRNA did not interfere with cis-trans interactions. Importantly, the 3'-UTR binding activity was significantly up-regulated in the presence of ethanol. UV cross-link analysis detected three NR1 3'-UTR binding proteins and their molecular mass calculated by Northwestern analysis was approximately 88, 60 and 47 kDa, respectively. Northwestern analysis showed a significant up-regulation of the 88-kDa protein after chronic ethanol treatment. The 88-kDa protein was purified and identified by tandem mass spectrometry as the beta subunit of alpha glucosidase II (GIIbeta). That GIIbeta is indeed a trans-acting protein and binds specifically to 3'-UTR of NR1 mRNA was confirmed by RNA gel mobility supershift assays and immuno RT-PCR. Western blotting data established a significant increase of GIIbeta polypeptide in chronic ethanol-exposed fetal cortical neurons. We hypothesize that the identified cis-acting region and the associated RNA-binding proteins are important regulators of NR1 subunit gene expression.
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MESH Headings
- 3' Untranslated Regions/drug effects
- Animals
- Blotting, Northern/methods
- Blotting, Western/methods
- Cells, Cultured
- Central Nervous System Depressants/pharmacology
- Cerebral Cortex/cytology
- Electrophoretic Mobility Shift Assay/methods
- Embryo, Mammalian
- Ethanol/pharmacology
- Immunoprecipitation/methods
- Mice
- Mice, Inbred C57BL
- Neurons/drug effects
- Neurons/physiology
- Protein Binding/drug effects
- Protein Biosynthesis/drug effects
- RNA, Messenger/metabolism
- RNA-Binding Proteins/physiology
- Receptors, N-Methyl-D-Aspartate/genetics
- Receptors, N-Methyl-D-Aspartate/physiology
- Regulatory Sequences, Ribonucleic Acid
- Reverse Transcriptase Polymerase Chain Reaction/methods
- Transcription, Genetic
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Affiliation(s)
- Antje Anji
- Department of Anatomy and Physiology, College of Veterinary Medicine, Kansas State University, Manhattan, KS 66506, USA
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12
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Bai Y, Lu H, Machida CA. CRM 1-mediated degradation and agonist-induced down-regulation of beta-adrenergic receptor mRNAs. BIOCHIMICA ET BIOPHYSICA ACTA-MOLECULAR CELL RESEARCH 2006; 1763:1076-89. [PMID: 16997396 PMCID: PMC1896136 DOI: 10.1016/j.bbamcr.2006.08.009] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/16/2006] [Revised: 08/11/2006] [Accepted: 08/14/2006] [Indexed: 10/24/2022]
Abstract
The beta1-adrenergic receptor (beta1-AR) mRNAs are post-transcriptionally regulated at the level of mRNA stability and undergo accelerated agonist-mediated degradation via interaction of its 3' untranslated region (UTR) with RNA binding proteins, including the HuR nuclear protein. In a previous report [Kirigiti et al. (2001). Mol. Pharmacol. 60:1308-1324], we examined the agonist-mediated down-regulation of the rat beta1-AR mRNAs, endogenously expressed in the rat C6 cell line and ectopically expressed in transfectant hamster DDT1MF2 and rat L6 cells. In this report, we determined that isoproterenol treatment of neonatal rat cortical neurons, an important cell type expressing beta1-ARs in the brain, results in significant decreases in beta1-AR mRNA stability, while treatment with leptomycin B, an inhibitor of the nuclear export receptor CRM 1, results in significant increases in beta1-AR mRNA stability and nuclear retention. UV-crosslinking/immunoprecipitation and glycerol gradient fractionation analyses indicate that the beta1-AR 3' UTR recognize complexes composed of HuR and multiple proteins, including CRM 1. Cell-permeable peptides containing the leucine-rich nuclear export signal (NES) were used as inhibitors of CRM 1-mediated nuclear export. When DDT1MF2 transfectants were treated with isoproterenol and peptide inhibitors, only the co-addition of the NES inhibitor reversed the isoproterenol-induced reduction of beta1-AR mRNA levels. Our results suggest that CRM 1-dependent NES-mediated mechanisms influence the degradation and agonist-mediated down-regulation of the beta1-AR mRNAs.
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MESH Headings
- 3' Untranslated Regions
- Adrenergic beta-1 Receptor Agonists
- Animals
- Animals, Newborn
- Antigens, Surface/metabolism
- Cell Line, Tumor
- Cell Nucleus/metabolism
- Cells, Cultured
- Cricetinae
- Down-Regulation
- ELAV Proteins
- ELAV-Like Protein 1
- Fatty Acids, Unsaturated/pharmacology
- Isoproterenol/pharmacology
- Models, Biological
- Neurons/metabolism
- Nuclear Export Signals
- RNA Stability
- RNA, Messenger/metabolism
- RNA-Binding Proteins/metabolism
- Rats
- Receptors, Adrenergic, beta-1/genetics
- Receptors, Adrenergic, beta-1/metabolism
- Receptors, Cytoplasmic and Nuclear/antagonists & inhibitors
- Receptors, Cytoplasmic and Nuclear/metabolism
- Receptors, Cytoplasmic and Nuclear/physiology
- Transfection
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Affiliation(s)
- Ying Bai
- Department of Integrative Biosciences, School of Dentistry, Oregon Health & Science University, Portland, OR 97239, USA
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13
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Rimessi P, Spitali P, Ando Y, Mazzaferro V, Pastorelli F, Tassinari CA, Calzolari E, Salvi F, Ferlini A. Transthyretin RNA profiling in livers from transplanted patients affected by familial amyloidotic polyneuropathy, and identification of a dual transcription start point. Liver Int 2006; 26:211-20. [PMID: 16448460 DOI: 10.1111/j.1478-3231.2005.01208.x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/13/2023]
Abstract
Mutations in the transthyretin (TTR) gene cause familial amyloidotic polyneuropathy (FAP), an autosomal dominant peripheral neuropathy, often associated with cardiomyopathy. Liver transplant currently represents a powerful therapeutic approach for FAP patients, although its efficacy is heavily dependent both on the disease severity and on the cardiac functionality. We have investigated the TTR gene expression searching for tissue-specific additional messengers in human adult and foetal tissues as well as in eight livers from FAP transplanted patients carrying different TTR mutations (Met30, Pro36, Ala47, Arg50, and Gln89). We identified a novel transcript, recognising a different transcription start site. The additional 5'-UTR sequence of this novel transcript contains regulatory boxes possibly highlighting an additional transcription start point. RNA analysis revealed that this region is represented in all foetal/adult tissues analysed. We discussed the implications of this finding which might provide perspectives for better understanding the TTR gene expression.
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Affiliation(s)
- Paola Rimessi
- Dipartimento di Medicina Sperimentale e Diagnostica, Sezione di Genetica Medica, University of Ferrara, Ferrara, Italy
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14
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Pullmann R, Juhaszova M, López de Silanes I, Kawai T, Mazan-Mamczarz K, Halushka MK, Gorospe M. Enhanced proliferation of cultured human vascular smooth muscle cells linked to increased function of RNA-binding protein HuR. J Biol Chem 2005; 280:22819-26. [PMID: 15824116 PMCID: PMC1350862 DOI: 10.1074/jbc.m501106200] [Citation(s) in RCA: 55] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
In dividing cells, the RNA-binding protein HuR associates with and stabilizes labile mRNAs encoding proliferative proteins, events that are linked to the increased cytoplasmic presence of HuR. Here, assessment of HuR levels in various vascular pathologies (intimal hyperplasia, atherosclerosis and neointimal proliferation, sclerosis of arterialized saphenous venous graft, and fibromuscular dysplasia) revealed a distinct increase in HuR expression and cytoplasmic abundance within the intima and neointima layers. On the basis of these observations, we postulated a role for HuR in promoting the proliferation of vascular smooth muscle cells. To test this hypothesis directly, we investigated the expression, subcellular localization, and proliferative influence of HuR in human vascular smooth muscle cells (hVSMCs). Treatment of hVSMCs with platelet-derived growth factor increased HuR levels in the cytoplasm, thereby influencing the expression of metabolic, proliferative, and structural genes. Importantly, knockdown of HuR expression by using RNA interference caused a reduction of hVSMC proliferation, both basally and following platelet-derived growth factor treatment. We propose that HuR contributes to regulating hVSMC growth and homeostasis in pathologies associated with vascular smooth muscle proliferation.
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Affiliation(s)
- Rudolf Pullmann
- Laboratory of Cellular and Molecular Biology and Laboratory of Cardiovascular Sciences, NIA-Intramural Research Program, National Institutes of Health, Baltimore, Maryland 21224, USA
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15
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Abstract
RhoB is a small GTP-binding protein that is involved in apoptotic signal transduction. We have cloned the mouse RhoB mRNA including a 1377 nucleotide 3'-untranslated region (UTR) that contains six AU-rich elements (AREs) as well as several uridine-rich stretches. There is 94% homology overall between the mouse and rat RhoB genes and 92% homology between the mouse and a putative human clone. Ultraviolet light (UVL) induces RhoB production through regulated changes in gene transcription and mRNA stabilization although the latter mechanism is unknown. We observed that UVL increased the half-life of RhoB mRNA from 63 min to 3.3 h in NIH/3T3 cells and from 87 min to 2.7 h in normal human keratinocyte cells. In vitro mobility shift assays demonstrated that HuR bound the 3'-UTR of RhoB at three distinct locations (nucleotides 1342-1696, 1765-1920 and 1897-1977) suggesting a regulatory role for this RNA-binding protein. HuR immunoprecipitations were positive for RhoB mRNA indicating an in vivo association, and Western blot analysis and immunofluorescence demonstrated that HuR rapidly partitions from the nucleus to the cytoplasm after UVL. Therefore, we propose a model in which UVL induces stress-activated signal transduction leading to nuclear/cytoplasmic shuttling of HuR and subsequent stabilization of RhoB mRNA.
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Affiliation(s)
- Cara J Westmark
- Department of Pathology and Laboratory Medicine, Waisman Center for Developmental Disabilities, University of Wisconsin, Madison, WI 53705, USA
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16
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Headley VV, Tanveer R, Greene SM, Zweifach A, Port JD. Reciprocal regulation of beta-adrenergic receptor mRNA stability by mitogen activated protein kinase activation and inhibition. Mol Cell Biochem 2004; 258:109-19. [PMID: 15030175 DOI: 10.1023/b:mcbi.0000012841.03400.42] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
Genes encoding numerous proto-oncogenes and cytokines, as well as a number of G-protein coupled receptors, are regulated post-transcriptionally at the level of mRNA stability. A common feature of all of these genes is the presence of A + U-rich elements (AREs) within their 3' untranslated regions. We, and others, have demonstrated previously that mRNAs encoding beta-adrenergic receptors (beta-ARs) are destabilized by agonist stimulation of the beta-AR/Galphas/adenylylcyclase pathway. However, in addition to PK-A, beta-ARs can also activate or inhibit mitogen activated kinase (MAPK) cascades, in a cell-type dependent basis. Recent evidence points to an important role for MAPKs in regulating the turnover of cytokine mRNAs, such as TNFalpha. We hypothesized that activation of MAPK's may also regulate beta-AR mRNA stability. The studies conducted herein demonstrate that generalized stimulation of MAPKs (JNK, p38) with anisomycin resulted in marked stabilization of beta-AR mRNA. Reciprocally, selective inhibition of JNK with SP600125 significantly decreased beta-AR mRNA half-life. Similarly, inhibition of the MEK/ERK pathway with either PD98059 or U0126 decreased beta-AR mRNA stability substantially. However, inhibition of p38 MAPK with SB203580 produced destabilization of beta-AR mRNA only at higher, non pharmacologically selective concentrations. In contrast to their effects on several other ARE containing mRNAs, inhibition of tyrosine kinases by genistein or PI3K by wortmannin, had no detectable effect on beta-AR mRNA stability. In summary, these results demonstrate for the first time that modulation of MAPK pathways can bi-directionally influence beta-AR mRNA stability.
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Affiliation(s)
- Violetta V Headley
- Department of Medicine, Division of Cardiology, University of Colorado Health Sciences Center, Denver, CO 80262, USA
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17
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Kandasamy K, Joseph K, Subramaniam K, Raymond JR, Tholanikunnel BG. Translational control of beta2-adrenergic receptor mRNA by T-cell-restricted intracellular antigen-related protein. J Biol Chem 2004; 280:1931-43. [PMID: 15536087 DOI: 10.1074/jbc.m405937200] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Cellular expression of the beta(2)-adrenergic receptor (beta(2)-AR) is suppressed at the translational level by 3'-untranslated region (UTR) sequences. To test the possible role of 3'-UTR-binding proteins in translational suppression of beta(2)-AR mRNA, we expressed the full-length 3'-UTR or the adenylate/uridylate-rich (A+U-rich element (ARE)) RNA from the 3'-UTR sequences of beta(2)-AR in cell lines that endogenously express this receptor. Reversal of beta(2)-adrenergic receptor translational repression by retroviral expression of 3'-UTR sequences suggested that ARE RNA-binding proteins are involved in translational suppression of beta(2)-adrenergic receptor expression. Using a 20-nucleotide ARE RNA from the receptor 3'-UTR as an affinity ligand, we purified the proteins that bind to these sequences. T-cell-restricted intracellular antigen-related protein (TIAR) was one of the strongly bound proteins identified by this method. UV-catalyzed cross-linking experiments using in vitro transcribed 3'-UTR RNA and glutathione S-transferase-TIAR demonstrated multiple binding sites for this protein on beta(2)-AR 3'-UTR sequences. The distal 340-nucleotide region of the 3'-UTR was identified as a target RNA motif for TIAR binding by both RNA gel shift analysis and immunoprecipitation experiments. Overexpression of TIAR resulted in suppression of receptor protein synthesis and a significant shift in endogenously expressed beta(2)-AR mRNA toward low molecular weight fractions in sucrose gradient polysome fractionation. Taken together, our results provide the first evidence for translational control of beta(2)-AR mRNA by TIAR.
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Affiliation(s)
- Karthikeyan Kandasamy
- Department of Medicine and Division of Nephrology, Medical University of South Carolina, Charleston, South Carolina 29425-2221, USA
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18
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Gardner LA, Delos Santos NM, Matta SG, Whitt MA, Bahouth SW. Role of the Cyclic AMP-dependent Protein Kinase in Homologous Resensitization of the β1-Adrenergic Receptor. J Biol Chem 2004; 279:21135-43. [PMID: 14990580 DOI: 10.1074/jbc.m313652200] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
A fundamental question in biology is how the various motifs in G protein-coupled receptors participate in the divergent functions orchestrated by these molecules. Here we describe a fundamental role for a serine residue at position 312 in the third intracellular loop of the human beta(1)-adrenergic receptor (beta(1)-AR) in endocytic recycling of the agonist-internalized receptor. In receptor recycling experiments that were monitored by confocal microscopy, the agonist-internalized wild-type (WT) beta(1)-AR recycled with a t(0.5) of 14 +/- 3 min. Mutagenesis of Ser(312) to alanine (Ser(312) --> Ala beta(1)-AR) or to the phosphoserine mimic aspartic acid (Ser(312) --> Asp beta(1)-AR) resulted in beta(1)-AR constructs that were pharmacologically indistinguishable from the WT beta(1)-AR. The internalized Ser(312) --> Asp beta(1)-AR recycled efficiently with a t(0.5) of 11 +/- 3 min, whereas the internalized Ser(312) --> Ala beta(1)-AR was not recycled or functionally resensitized through the endosomal pathway. Because this serine is a putative residue for phosphorylation by the cyclic AMP-dependent protein kinase (PKA), we examined the role of this kinase in recycling of the internalized beta(1)-AR. Inhibition of PKA biochemically or genetically using a dominant negative PKA construct blocked the recycling of the internalized WT beta(1)-AR. Phosphorylation studies revealed that the beta(1)-AR is partially phosphorylated by PKA and that phosphorylation of the beta(1)-AR by the catalytic subunit of PKA occurs exclusively at Ser(312). Our results identify a new signaling paradigm in which homologous activation of a kinase provides a reversible modification that shifts the itinerary of the internalized receptor toward recycling and resensitization. Therefore, PKA-mediated phosphorylation of G protein-coupled receptors might result in motif-dependent desensitization or resensitization.
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Affiliation(s)
- Lidia A Gardner
- Pharmacology and Molecular Sciences, University of Tennessee Health Sciences Center, 874 Union Avenue, Memphis, TN 38163, USA
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19
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Simm A, Casselmann C, Schubert A, Hofmann S, Reimann A, Silber RE. Age associated changes of AGE-receptor expression: RAGE upregulation is associated with human heart dysfunction. Exp Gerontol 2004; 39:407-13. [PMID: 15036400 DOI: 10.1016/j.exger.2003.12.006] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2003] [Revised: 12/12/2003] [Accepted: 12/16/2003] [Indexed: 11/28/2022]
Abstract
The binding of advanced glycation endproducts (AGEs) to their receptors is known to cause changes in cell function during normal ageing and is implicated in the pathogenesis of cardiovascular disease. In this study, expression of the AGE-receptor 3 (AGE-R3) and the receptor for AGEs (RAGE) was compared on the mRNA and protein level in the ageing human heart. Western blot and RT-PCR analysis of the AGE receptors from the cardiac auricles in senescent and adult patients was performed and compared with young controls. Whereas the expressions of AGE-R3 as well as RAGE protein were significantly upregulated in the senescent population, only the upregulation of RAGE is associated with reduced heart function. Therefore, our results support a pathophysiological function for RAGE in the ageing human heart.
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Affiliation(s)
- A Simm
- Department of Cardio-Thoracic-Surgery, University of Halle-Wittenberg, Ernst-Grube Str. 40, D-06120 Halle, Germany.
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20
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Michelotti GA, Bauman MJ, Smith MP, Schwinn DA. Cloning and characterization of the rat alpha 1a-adrenergic receptor gene promoter. Demonstration of cell specificity and regulation by hypoxia. J Biol Chem 2003; 278:8693-705. [PMID: 12471020 DOI: 10.1074/jbc.m211986200] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023] Open
Abstract
Recent studies reveal important and distinct roles for cardiac alpha(1a) adrenergic receptors (alpha(1a)ARs). Surprisingly, given their importance in myocardial ischemia/reperfusion, hypoxia, and hypertrophy as well as frequent use of rat cardiomyocyte model systems, the rat alpha(1a)AR gene promoter has never been characterized. Therefore, we isolated 3.9 kb of rat alpha(1a)AR 5'-untranslated region and 5'-regulatory sequences and identified multiple transcription initiation sites. One proximal (P1) and several clustered upstream distal promoters (P2, P3, and P4) were delineated. Sequences surrounding both proximal and distal promoters lack typical TATA or CCAAT boxes but contain cis-elements for multiple myocardium-relevant nuclear regulators including Sp1, GATA, and CREB, findings consistent with enhanced cardiac basal alpha(1a)AR expression seen in Northern blots and reporter constructs. Promoter analysis using deletion reporter constructs reveals, in addition to a powerful upstream enhancer, a key region (-558/-542) important in regulating all alpha(1a)AR promoters with hypoxic stress. Gel shift analysis of this 14-bp region confirms a hypoxia-induced shift independent of direct hypoxia-inducible factor binding. Mutational analysis of this sequence identifies a novel 9-bp hypoxia response element, the loss of which severely attenuates hypoxia-mediated repression of alpha(1a)AR transcription. These findings for the alpha(1a) gene should facilitate elucidation of alpha(1)AR-mediated mechanisms involved in distinct myocardial pathologies.
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MESH Headings
- 5' Untranslated Regions
- Animals
- Base Sequence
- Blotting, Northern
- Cell Hypoxia
- Cells, Cultured
- Cloning, Molecular
- DNA
- Electrophoretic Mobility Shift Assay
- Gene Expression Regulation
- Promoter Regions, Genetic
- RNA, Messenger/genetics
- Rats
- Receptors, Adrenergic, alpha-1/chemistry
- Receptors, Adrenergic, alpha-1/genetics
- Receptors, Adrenergic, alpha-1/metabolism
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Affiliation(s)
- Gregory A Michelotti
- Department of Pharmacology and Cancer Biology, Duke University Medical Center, Durham, North Carolina 27710, USA
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