1
|
Cao Z, Yan L, Shen Z, Chen Y, Shi Y, He X, Zhou N. A novel splice variant of Gαq-coupled Bombyx CAPA-PVK receptor 1 functions as a specific Gαi/o-linked receptor for CAPA-PK. BIOCHIMICA ET BIOPHYSICA ACTA-MOLECULAR CELL RESEARCH 2020; 1867:118718. [PMID: 32289337 DOI: 10.1016/j.bbamcr.2020.118718] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/10/2020] [Revised: 04/05/2020] [Accepted: 04/07/2020] [Indexed: 01/04/2023]
Abstract
Alternative splicing enables G protein-coupled receptor (GPCR) genes to greatly increase the number of structurally and functionally distinct receptor isoforms. However, the functional role and relevance of the individual GPCR splice variants in regulating physiological processes are still to be assessed. A naturally occurring alternative splice variant of Bombyx CAPA-PVK receptor, BomCAPA-PVK-R1-Δ341, has been shown to act as a dominant-negative protein to regulate cell surface expression and function of the canonical CAPA-PVK receptor. Herein, using functional assays, we identify the splice variant Δ341 as a specific receptor for neuropeptide CAPA-PK, and upon activation, Δ341 signals to ERK1/2 pathway. Further characterization demonstrates that Δ341 couples to Gαi/o, distinct from the Gαq-coupled canonical CAPA-PVK receptor, triggering ERK1/2 phosphorylation through Gβγ-PI3K-PKCζ signaling cascade. Moreover, our ELISA data show that the ligand-dependent internalization of the splice variant Δ341 is significantly impaired due to lack of GRKs-mediated phosphorylation sites. Our findings highlight the potential of this knowledge for molecular, pharmacological and physiological studies on GPCR splice variants in the future.
Collapse
Affiliation(s)
- Zheng Cao
- Institute of Biochemistry, College of Life Sciences, Zijingang Campus, Zhejiang University, Hangzhou, Zhejiang 310058, China
| | - Lili Yan
- Institute of Biochemistry, College of Life Sciences, Zijingang Campus, Zhejiang University, Hangzhou, Zhejiang 310058, China
| | - Zhangfei Shen
- Department of Economic Zoology, College of Animal Sciences, Zijingang Campus, Zhejiang University, Hangzhou, Zhejiang 310058, China
| | - Yu Chen
- Institute of Biochemistry, College of Life Sciences, Zijingang Campus, Zhejiang University, Hangzhou, Zhejiang 310058, China
| | - Ying Shi
- Institute of Biochemistry, College of Life Sciences, Zijingang Campus, Zhejiang University, Hangzhou, Zhejiang 310058, China
| | - Xiaobai He
- College of Biotechnology, Jiangsu University of Science and Technology, Zhenjiang, Jiangsu 212018, China
| | - Naiming Zhou
- Institute of Biochemistry, College of Life Sciences, Zijingang Campus, Zhejiang University, Hangzhou, Zhejiang 310058, China.
| |
Collapse
|
2
|
Cao X, Li Y. β 3-Adrenergic receptor regulates hepatic apolipoprotein A-I gene expression. J Clin Lipidol 2017; 11:1168-1176. [PMID: 28802864 DOI: 10.1016/j.jacl.2017.07.007] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2017] [Revised: 07/19/2017] [Accepted: 07/21/2017] [Indexed: 11/28/2022]
Abstract
BACKGROUND β3-adrenergic receptor (β3-AR) was shown to upregulate hepatic apolipoprotein A-I (apoA-I) expression and reverse atherosclerotic plaques in vivo experiments. However, the effect of β3-AR on apoA-I expression in vitro is unknown. The specific mechanism underlying β3-AR prevention of atherosclerosis is unclear. OBJECTIVE The present study was designed to investigate the molecular mechanism of β3-AR-mediated regulation of hepatic apoA-I gene expression. METHODS HepG2 cells were preincubated with/without a selective protein kinase A inhibitor (H-89) and then treated with a selective β3-AR agonist (BRL37344) or antagonist (SR59230A). The hepatic apoA-I expression was detected by reverse transcription real-time quantitative polymerase chain reaction and Western blot analysis. Enzyme-linked immunosorbent assay was used to evaluate the secretion of apoA-I. A recombinant plasmid containing the apoA-I promoter was constructed and transiently transfected into HepG2 cells, and dual-luciferase reporter assays were used to examine the activity of the apoA-I promoter. A chromatin immunoprecipitation polymerase chain reaction assay was used to evaluate binding activities of hepatocyte nuclear factor-4 (HNF-4), HNF-3, and early growth response protein-1. RESULTS β3-AR activation significantly upregulated apoA-I expression, promoted apoA-I secretion, and enhanced the activities of the apoA-I promoter, HNF-4, and HNF-3 in hepatocytes, whereas early growth response protein-1 was not affected. Moreover, protein kinase A inhibition partially suppressed the activation of the apoA-I promoter, HNF-4, and HNF-3 and almost completely blocked the upregulation of apoA-I expression induced by β3-AR. CONCLUSION β3-AR activation increased the activities of the apoA-I promoter, HNF-4, and HNF-3, which might account for the mechanism of β3-AR-mediated upregulation of hepatic apoA-I expression. β3-AR might exert an anti-atherosclerotic effect by upregulating hepatic apoA-I expression and promoting the cholesterol reverse transport process.
Collapse
Affiliation(s)
- Xiaojing Cao
- Emergency Department, Beijing Anzhen Hospital, Capital Medical University, ChaoYang District, Beijing, China
| | - Yanfang Li
- Emergency Department, Beijing Anzhen Hospital, Capital Medical University, ChaoYang District, Beijing, China.
| |
Collapse
|
3
|
Oladosu FA, Maixner W, Nackley AG. Alternative Splicing of G Protein-Coupled Receptors: Relevance to Pain Management. Mayo Clin Proc 2015; 90:1135-51. [PMID: 26250730 PMCID: PMC5024555 DOI: 10.1016/j.mayocp.2015.06.010] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/27/2015] [Revised: 06/13/2015] [Accepted: 06/26/2015] [Indexed: 01/01/2023]
Abstract
Drugs that target G protein-coupled receptors (GPCRs) represent the primary treatment strategy for patients with acute and chronic pain; however, there is substantial individual variability in both the efficacy and adverse effects associated with these drugs. Variability in drug responses is due, in part, to individuals' diversity in alternative splicing of pain-relevant GPCRs. G protein-coupled receptor alternative splice variants often exhibit distinct tissue distribution patterns, drug-binding properties, and signaling characteristics that may impact disease pathology as well as the extent and direction of analgesic effects. We review the importance of GPCRs and their known splice variants to the management of pain.
Collapse
Affiliation(s)
- Folabomi A Oladosu
- Center for Pain Research and Innovation, University of North Carolina, Chapel Hill
| | - William Maixner
- Center for Pain Research and Innovation, University of North Carolina, Chapel Hill
| | - Andrea G Nackley
- Center for Pain Research and Innovation, University of North Carolina, Chapel Hill.
| |
Collapse
|
4
|
Imbrogno S, Gattuso A, Mazza R, Angelone T, Cerra MC. β3 -AR and the vertebrate heart: a comparative view. Acta Physiol (Oxf) 2015; 214:158-75. [PMID: 25809182 DOI: 10.1111/apha.12493] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2014] [Revised: 11/04/2014] [Accepted: 03/16/2015] [Indexed: 01/13/2023]
Abstract
Recent cardiovascular research showed that, together with β1- and β2-adrenergic receptors (ARs), β3-ARs contribute to the catecholamine (CA)-dependent control of the heart. β3-ARs structure, function and ligands were investigated in mammals because of their applicative potential in human cardiovascular diseases. Only recently, the concept of a β3-AR-dependent cardiac modulation was extended to non-mammalian vertebrates, although information is still scarce and fragmentary. β3-ARs were structurally described in fish, showing a closer relationship to mammalian β1-AR than β2-AR. Functional β3-ARs are present in the cardiac tissue of teleosts and amphibians. As in mammals, activation of these receptors elicits a negative modulation of the inotropic performance through the involvement of the endothelium endocardium (EE), Gi/0 proteins and the nitric oxide (NO) signalling. This review aims to comparatively analyse data from literature on β3-ARs in mammals, with those on teleosts and amphibians. The purpose is to highlight aspects of uniformity and diversity of β3-ARs structure, ligands activity, function and signalling cascades throughout vertebrates. This may provide new perspectives aimed to clarify the biological relevance of β3-ARs in the context of the nervous and humoral control of the heart and its functional plasticity.
Collapse
Affiliation(s)
- S. Imbrogno
- Department of Biology, Ecology and Earth Sciences; University of Calabria; Arcavacata di Rende Italy
| | - A. Gattuso
- Department of Biology, Ecology and Earth Sciences; University of Calabria; Arcavacata di Rende Italy
| | - R. Mazza
- Department of Biology, Ecology and Earth Sciences; University of Calabria; Arcavacata di Rende Italy
| | - T. Angelone
- Department of Biology, Ecology and Earth Sciences; University of Calabria; Arcavacata di Rende Italy
- National Institute of Cardiovascular Research; Bologna Italy
| | - M. C. Cerra
- Department of Biology, Ecology and Earth Sciences; University of Calabria; Arcavacata di Rende Italy
- National Institute of Cardiovascular Research; Bologna Italy
| |
Collapse
|
5
|
Jun JG, Maeda S, Kuwahara-Otani S, Tanaka K, Hayakawa T, Seki M. Expression of adrenergic and cholinergic receptors in murine renal intercalated cells. J Vet Med Sci 2014; 76:1493-500. [PMID: 25069412 PMCID: PMC4272982 DOI: 10.1292/jvms.14-0315] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Neurons influence renal function and help to regulate fluid homeostasis, blood
pressure and ion excretion. Intercalated cells (ICCs) are distributed throughout the renal
collecting ducts and help regulate acid/base equilibration. Because ICCs are located among
principal cells, it has been difficult to determine the effects that efferent nerve fibers
have on this cell population. In this study, we examined the expression of
neurotransmitter receptors on the murine renal epithelial M-1 cell line. We found that M-1
cells express a2 and b2 adrenergic receptor mRNA and the b2 receptor protein. Further, b2
receptor-positive cells in the murine cortical collecting ducts also express AQP6,
indicating that these cells are ICCs. M-1 cells were found to express m1, m4 and m5
muscarinic receptor mRNAs and the m1 receptor protein. Cells in the collecting ducts also
express the m1 receptor protein, and some m1-positive cells express AQP6.
Acetylcholinesterase was detected in cortical collecting duct cells. Interestingly,
acetylcholinesterase-positive cells neighbored AQP6-positive cells, suggesting that
principal cells may regulate the availability of acetylcholine. In conclusion, our data
suggest that ICCs in murine renal collecting ducts may be regulated by the adrenergic and
cholinergic systems.
Collapse
Affiliation(s)
- Jin-Gon Jun
- Department of Anatomy and Cell Biology, Hyogo College of Medicine, 1-1 Mukogowa, Nishinomiya, Hyogo 663-8501, Japan
| | | | | | | | | | | |
Collapse
|
6
|
Wang X, Chu MMS, Wong AOL. Signaling mechanisms for alpha2-adrenergic inhibition of PACAP-induced growth hormone secretion and gene expression grass carp pituitary cells. Am J Physiol Endocrinol Metab 2007; 292:E1750-62. [PMID: 17311897 DOI: 10.1152/ajpendo.00001.2007] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Pituitary adenylate cyclase-activating polypeptide (PACAP) is a potent growth hormone (GH)-releasing factor in lower vertebrates. However, its functional interactions with other GH regulators have not been fully characterized. In fish models, norepinephrine (NE) inhibits GH release at the pituitary cell level, but its effects on GH synthesis have yet to be determined. We examined adrenergic inhibition of PACAP-induced GH secretion and GH gene expression using grass carp pituitary cells as a cell model. Through activation of pituitary alpha2-adrenoreceptors, NE or the alpha2-agonist clonidine reduced both basal and PACAP-induced GH release and GH mRNA expression. In carp pituitary cells, clonidine also suppressed cAMP production and intracellular Ca2+ levels and blocked PACAP induction of these two second messenger signals. In GH3 cells transfected with a reporter carrying the grass carp GH promoter, PACAP stimulation increased GH promoter activity, and this stimulatory effect could be abolished by NE treatment. In parallel experiments, clonidine reduced GH primary transcript and GH promoter activity without affecting GH mRNA stability, and these inhibitory actions were mimicked by inhibiting adenylate cyclase (AC), blocking protein kinase A (PKA), removing extracellular Ca2+ in the culture medium, or inactivating L-type voltage-sensitive Ca2+ channels (VSCC). Since our recent studies have shown that PACAP can induce GH secretion in carp pituitary cells through cAMP/PKA- and Ca2+/calmodulin-dependent mechanisms, these results, taken together, suggest that alpha2-adrenergic stimulation in the carp pituitary may inhibit PACAP-induced GH release and GH gene transcription by blocking the AC/cAMP/PKA pathway and Ca2+ entry through L-type VSCC.
Collapse
Affiliation(s)
- Xinyan Wang
- Department of Zoology, University of Hong Kong, Pokfulam Road, Hong Kong, China
| | | | | |
Collapse
|
7
|
Wong AOL, Chuk MCY, Chan HC, Lee EKY. Mechanisms for gonadotropin-releasing hormone potentiation of growth hormone rebound following norepinephrine inhibition in goldfish pituitary cells. Am J Physiol Endocrinol Metab 2007; 292:E203-14. [PMID: 16940469 DOI: 10.1152/ajpendo.00337.2006] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
In the goldfish, norepinephrine (NE) inhibits growth hormone (GH) secretion through activation of pituitary alpha(2)-adrenergic receptors. Interestingly, a GH rebound is observed after NE withdrawal, which can be markedly enhanced by prior exposure to gonadotropin-releasing hormone (GnRH). Here we examined the mechanisms responsible for GnRH potentiation of this "postinhibition" GH rebound. In goldfish pituitary cells, alpha(2)-adrenergic stimulation suppressed both basal and GnRH-induced GH mRNA expression, suggesting that a rise in GH synthesis induced by GnRH did not contribute to its potentiating effect. Using a column perifusion approach, GnRH given during NE treatment consistently enhanced the GH rebound following NE withdrawal. This potentiating effect was mimicked by activation of PKC and adenylate cyclase (AC) but not by induction of Ca(2+) entry through voltage-sensitive Ca(2+) channels (VSCC). Furthermore, GnRH-potentiated GH rebound could be alleviated by inactivation of PKC, removal of extracellular Ca(2+), blockade of VSCC, and inhibition of Ca(2+)/calmodulin (CaM)-dependent protein kinase II (CaMKII). Inactivation of AC and PKA, however, was not effective in this regard. These results, as a whole, suggest that GnRH potentiation of GH rebound following NE inhibition is mediated by PKC coupled to Ca(2+) entry through VSCC and subsequent activation of CaMKII. Apparently, the Ca(2+)-dependent cascades are involved in GH secretion during the rebound phase but are not essential for the initiation of GnRH potentiation. Since GnRH has been previously shown to have no effects on cAMP synthesis in goldfish pituitary cells, the involvement of cAMP-dependent mechanisms in GnRH potentiation is rather unlikely.
Collapse
Affiliation(s)
- Anderson O L Wong
- Dept. of Zoology, Univ. of Hong Kong, Pokfulam Road, Hong Kong SAR, China.
| | | | | | | |
Collapse
|
8
|
Centurión D, Mehotra S, Sánchez-López A, Gupta S, MaassenVanDenBrink A, Villalón CM. Potential vascular α1-adrenoceptor blocking properties of an array of 5-HT receptor ligands in the rat. Eur J Pharmacol 2006; 535:234-42. [PMID: 16545797 DOI: 10.1016/j.ejphar.2006.02.010] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2006] [Accepted: 02/07/2006] [Indexed: 11/20/2022]
Abstract
This study set out to analyse the potential ability of some 5-hydroxytryptamine (5-HT) receptor ligands widely used in cardiovascular experimental models to interact with vascular alpha1-adrenoceptors in the pithed rat. These ligands included: methiothepin, methysergide and metergoline (5-HT(1)/5-HT2); WAY-100635, buspirone, ipsapirone and 8-hydroxy-2-(di-n-propylamino)tetralin (8-OH-DPAT) (5-HT(1A)); GR127935 (5-HT(1B/1D)); ketanserin, ritanserin, spiperone and pizotifen (5-HT2); granisetron and metoclopramide (5-HT3); tropisetron (5-HT3/5-HT4); ergotamine (5-HT(1B/1D), 5-ht(5A/5B)); clozapine (5-HT6/5-HT7); as well as LY215840 and mesulergine (5-HT2/5-HT7). For this purpose, the increases in diastolic blood pressure produced by the selective alpha1-adrenoceptor agonist, phenylephrine, were analysed before and after the above antagonists or saline. The adrenoceptor antagonist properties of prazosin (alpha1) and yohimbine (alpha2) were also analysed for comparison. Thus, the phenylephrine-induced vasopressor responses were dose-dependently antagonised with the following apparent rank order of potency by: prazosin > or = methiothepin > ketanserin > clozapine > or = lisuride >> buspirone; this potency correlates with the affinity of these compounds for alpha1-adrenoceptor binding sites. In contrast, the other compounds were either devoid of any blocking effect on--or even potentiated (i.e. lisuride, methysergide, 8-OH-DPAT, granisetron and GR127935)--the responses to phenylephrine. These results show that methiothepin, ketanserin, clozapine, lisuride and buspirone can block alpha1-adrenoceptors in the rat systemic vasculature.
Collapse
Affiliation(s)
- David Centurión
- Departamento de Farmacobiología, Cinvestav-Coapa., Czda. de los Tenorios 235, Col. Granjas-Coapa, 14330 México D.F., México
| | | | | | | | | | | |
Collapse
|
9
|
Abstract
The renal nerves are the communication link between the central nervous system and the kidney. In response to multiple peripheral and central inputs, efferent renal sympathetic nerve activity is altered so as to convey information to the major structural and functional components of the kidney, the vessels, glomeruli, and tubules, each of which is innervated. At the level of each of these individual components, information transfer occurs via interaction of the neurotransmitter released at the sympathetic nerve terminal-neuroeffector junction with specific postjunctional receptors coupled to defined intracellular signaling and effector systems. In response to normal physiological stimuli, changes in efferent renal sympathetic nerve activity contribute importantly to homeostatic regulation of renal blood flow, glomerular filtration rate, renal tubular epithelial cell solute and water transport, and hormonal release. Afferent input from sensory receptors located in the kidney participates in this reflex control system via renorenal reflexes that enable total renal function to be self-regulated and balanced between the two kidneys. In pathophysiological conditions, abnormal regulation of efferent renal sympathetic nerve activity contributes significantly to the associated abnormalities of renal function which, in turn, are of importance in the pathogenesis of the disease.
Collapse
Affiliation(s)
- G F DiBona
- Department of Internal Medicine, University of Iowa College of Medicine, Iowa City, USA
| | | |
Collapse
|