1
|
Maghsoudi S, Shuaib R, Van Bastelaere B, Dakshinamurti S. Adenylyl cyclase isoforms 5 and 6 in the cardiovascular system: complex regulation and divergent roles. Front Pharmacol 2024; 15:1370506. [PMID: 38633617 PMCID: PMC11021717 DOI: 10.3389/fphar.2024.1370506] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2024] [Accepted: 03/11/2024] [Indexed: 04/19/2024] Open
Abstract
Adenylyl cyclases (ACs) are crucial effector enzymes that transduce divergent signals from upstream receptor pathways and are responsible for catalyzing the conversion of ATP to cAMP. The ten AC isoforms are categorized into four main groups; the class III or calcium-inhibited family of ACs comprises AC5 and AC6. These enzymes are very closely related in structure and have a paucity of selective activators or inhibitors, making it difficult to distinguish them experimentally. AC5 and AC6 are highly expressed in the heart and vasculature, as well as the spinal cord and brain; AC6 is also abundant in the lungs, kidney, and liver. However, while AC5 and AC6 have similar expression patterns with some redundant functions, they have distinct physiological roles due to differing regulation and cAMP signaling compartmentation. AC5 is critical in cardiac and vascular function; AC6 is a key effector of vasodilatory pathways in vascular myocytes and is enriched in fetal/neonatal tissues. Expression of both AC5 and AC6 decreases in heart failure; however, AC5 disruption is cardio-protective, while overexpression of AC6 rescues cardiac function in cardiac injury. This is a comprehensive review of the complex regulation of AC5 and AC6 in the cardiovascular system, highlighting overexpression and knockout studies as well as transgenic models illuminating each enzyme and focusing on post-translational modifications that regulate their cellular localization and biological functions. We also describe pharmacological challenges in the design of isoform-selective activators or inhibitors for AC5 and AC6, which may be relevant to developing new therapeutic approaches for several cardiovascular diseases.
Collapse
Affiliation(s)
- Saeid Maghsoudi
- Department of Physiology and Pathophysiology, University of Manitoba, Winnipeg, MB, Canada
- Biology of Breathing Group, Children’s Hospital Research Institute of Manitoba, Winnipeg, MB, Canada
| | - Rabia Shuaib
- Biology of Breathing Group, Children’s Hospital Research Institute of Manitoba, Winnipeg, MB, Canada
| | - Ben Van Bastelaere
- Biology of Breathing Group, Children’s Hospital Research Institute of Manitoba, Winnipeg, MB, Canada
| | - Shyamala Dakshinamurti
- Department of Physiology and Pathophysiology, University of Manitoba, Winnipeg, MB, Canada
- Biology of Breathing Group, Children’s Hospital Research Institute of Manitoba, Winnipeg, MB, Canada
- Section of Neonatology, Department of Pediatrics, Health Sciences Centre, Winnipeg, MB, Canada
| |
Collapse
|
2
|
The Alpha-1 Subunit of the Na +/K +-ATPase (ATP1A1) Is a Host Factor Involved in the Attachment of Porcine Epidemic Diarrhea Virus. Int J Mol Sci 2023; 24:ijms24044000. [PMID: 36835408 PMCID: PMC9966514 DOI: 10.3390/ijms24044000] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2022] [Revised: 01/24/2023] [Accepted: 01/25/2023] [Indexed: 02/18/2023] Open
Abstract
Porcine epidemic diarrhea (PED) is an acute and severe atrophic enteritis caused by porcine epidemic diarrhea virus (PEDV) that infects pigs and makes huge economic losses to the global swine industry. Previously, researchers have believed that porcine aminopeptidase-N (pAPN) was the primary receptor for PEDV, but it has been found that PEDV can infect pAPN knockout pigs. Currently, the functional receptor for PEDV remains unspecified. In the present study, we performed virus overlay protein binding assay (VOPBA), found that ATP1A1 was the highest scoring protein in the mass spectrometry results, and confirmed that the CT structural domain of ATP1A1 interacts with PEDV S1. First, we investigated the effect of ATP1A1 on PEDV replication. Inhibition of hosts ATP1A1 protein expression using small interfering RNA (siRNAs) significantly reduced the cells susceptibility to PEDV. The ATP1A1-specific inhibitors Ouabain (a cardiac steroid) and PST2238 (a digitalis toxin derivative), which specifically bind ATP1A1, could block the ATP1A1 protein internalization and degradation, and consequently reduce the infection rate of host cells by PEDV significantly. Additionally, as expected, overexpression of ATP1A1 notably enhanced PEDV infection. Next, we observed that PEDV infection of target cells resulted in upregulation of ATP1A1 at the mRNA and protein levels. Furthermore, we found that the host protein ATP1A1 was involved in PEDV attachment and co-localized with PEDV S1 protein in the early stage of infection. In addition, pretreatment of IPEC-J2 and Vero-E6 cells with ATP1A1 mAb significantly reduced PEDV attachment. Our observations provided a perspective on identifying key factors in PEDV infection, and may provide valuable targets for PEDV infection, PEDV functional receptor, related pathogenesis, and the development of new antiviral drugs.
Collapse
|
3
|
Cyclic nucleotide phosphodiesterases as therapeutic targets in cardiac hypertrophy and heart failure. Nat Rev Cardiol 2023; 20:90-108. [PMID: 36050457 DOI: 10.1038/s41569-022-00756-z] [Citation(s) in RCA: 31] [Impact Index Per Article: 31.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 07/11/2022] [Indexed: 01/21/2023]
Abstract
Cyclic nucleotide phosphodiesterases (PDEs) modulate the neurohormonal regulation of cardiac function by degrading cAMP and cGMP. In cardiomyocytes, multiple PDE isozymes with different enzymatic properties and subcellular localization regulate local pools of cyclic nucleotides and specific functions. This organization is heavily perturbed during cardiac hypertrophy and heart failure (HF), which can contribute to disease progression. Clinically, PDE inhibition has been considered a promising approach to compensate for the catecholamine desensitization that accompanies HF. Although PDE3 inhibitors, such as milrinone or enoximone, have been used clinically to improve systolic function and alleviate the symptoms of acute HF, their chronic use has proved to be detrimental. Other PDEs, such as PDE1, PDE2, PDE4, PDE5, PDE9 and PDE10, have emerged as new potential targets to treat HF, each having a unique role in local cyclic nucleotide signalling pathways. In this Review, we describe cAMP and cGMP signalling in cardiomyocytes and present the various PDE families expressed in the heart as well as their modifications in pathological cardiac hypertrophy and HF. We also appraise the evidence from preclinical models as well as clinical data pointing to the use of inhibitors or activators of specific PDEs that could have therapeutic potential in HF.
Collapse
|
4
|
Opioid-Modulated Receptor Localization and Erk1/2 Phosphorylation in Cells Coexpressing μ-Opioid and Nociceptin Receptors. Int J Mol Sci 2023; 24:ijms24021048. [PMID: 36674576 PMCID: PMC9865058 DOI: 10.3390/ijms24021048] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2022] [Revised: 12/30/2022] [Accepted: 01/03/2023] [Indexed: 01/09/2023] Open
Abstract
We attempted to examine the alterations elicited by opioids via coexpressed μ-opioid (MOP) and nociceptin/orphanin FQ (NOP) receptors for receptor localization and Erk1/2 (p44/42 MAPK) in human embryonic kidney (HEK) 293 cells. Through two-photon microscopy, the proximity of MOP and NOP receptors was verified by fluorescence resonance energy transfer (FRET), and morphine but not buprenorphine facilitated the process of MOP-NOP heterodimerization. Single-particle tracking (SPT) further revealed that morphine or buprenorphine hindered the movement of the MOP-NOP heterodimers. After exposure to morphine or buprenorphine, receptor localization on lipid rafts was detected by immunocytochemistry, and phosphorylation of Erk1/2 was determined by immunoblotting in HEK 293 cells expressing MOP, NOP, or MOP+NOP receptors. Colocalization of MOP and NOP on lipid rafts was enhanced by morphine but not buprenorphine. Morphine stimulated the phosphorylation of Erk1/2 with a similar potency in HEK 293 cells expressing MOP and MOP+NOP receptors, but buprenorphine appeared to activate Erk1/2 solely through NOP receptors. Our results suggest that opioids can fine-tune the cellular localization of opioid receptors and phosphorylation of Erk1/2 in MOP+NOP-expressing cells.
Collapse
|
5
|
Mostafa S, Nader N, Machaca K. Lipid Signaling During Gamete Maturation. Front Cell Dev Biol 2022; 10:814876. [PMID: 36204680 PMCID: PMC9531329 DOI: 10.3389/fcell.2022.814876] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2021] [Accepted: 05/30/2022] [Indexed: 01/24/2023] Open
Abstract
Cell lipids are differentially distributed in distinct organelles and within the leaflets of the bilayer. They can further form laterally defined sub-domains within membranes with important signaling functions. This molecular and spatial complexity offers optimal platforms for signaling with the associated challenge of dissecting these pathways especially that lipid metabolism tends to be highly interconnected. Lipid signaling has historically been implicated in gamete function, however the detailed signaling pathways involved remain obscure. In this review we focus on oocyte and sperm maturation in an effort to consolidate current knowledge of the role of lipid signaling and set the stage for future directions.
Collapse
Affiliation(s)
- Sherif Mostafa
- Medical Program, WCMQ, Education City, Qatar Foundation, Doha, Qatar
| | - Nancy Nader
- Calcium Signaling Group, Research Department, Weill Cornell Medicine Qatar (WCMQ), Education City, Qatar Foundation, Doha, Qatar
- Department of Physiology and Biophysics, Weill Cornell Medicine, New York, NY, United States
| | - Khaled Machaca
- Calcium Signaling Group, Research Department, Weill Cornell Medicine Qatar (WCMQ), Education City, Qatar Foundation, Doha, Qatar
- Department of Physiology and Biophysics, Weill Cornell Medicine, New York, NY, United States
- *Correspondence: Khaled Machaca,
| |
Collapse
|
6
|
Ostrom KF, LaVigne JE, Brust TF, Seifert R, Dessauer CW, Watts VJ, Ostrom RS. Physiological roles of mammalian transmembrane adenylyl cyclase isoforms. Physiol Rev 2022; 102:815-857. [PMID: 34698552 PMCID: PMC8759965 DOI: 10.1152/physrev.00013.2021] [Citation(s) in RCA: 38] [Impact Index Per Article: 19.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2021] [Revised: 09/20/2021] [Accepted: 10/19/2021] [Indexed: 12/12/2022] Open
Abstract
Adenylyl cyclases (ACs) catalyze the conversion of ATP to the ubiquitous second messenger cAMP. Mammals possess nine isoforms of transmembrane ACs, dubbed AC1-9, that serve as major effector enzymes of G protein-coupled receptors (GPCRs). The transmembrane ACs display varying expression patterns across tissues, giving the potential for them to have a wide array of physiological roles. Cells express multiple AC isoforms, implying that ACs have redundant functions. Furthermore, all transmembrane ACs are activated by Gαs, so it was long assumed that all ACs are activated by Gαs-coupled GPCRs. AC isoforms partition to different microdomains of the plasma membrane and form prearranged signaling complexes with specific GPCRs that contribute to cAMP signaling compartments. This compartmentation allows for a diversity of cellular and physiological responses by enabling unique signaling events to be triggered by different pools of cAMP. Isoform-specific pharmacological activators or inhibitors are lacking for most ACs, making knockdown and overexpression the primary tools for examining the physiological roles of a given isoform. Much progress has been made in understanding the physiological effects mediated through individual transmembrane ACs. GPCR-AC-cAMP signaling pathways play significant roles in regulating functions of every cell and tissue, so understanding each AC isoform's role holds potential for uncovering new approaches for treating a vast array of pathophysiological conditions.
Collapse
Affiliation(s)
| | - Justin E LaVigne
- Department of Medicinal Chemistry and Molecular Pharmacology, Purdue University, West Lafayette, Indiana
| | - Tarsis F Brust
- Department of Pharmaceutical Sciences, Lloyd L. Gregory School of Pharmacy, Palm Beach Atlantic University, West Palm Beach, Florida
| | - Roland Seifert
- Institute of Pharmacology, Hannover Medical School, Hannover, Germany
| | - Carmen W Dessauer
- Department of Integrative Biology and Pharmacology, McGovern Medical School, The University of Texas Health Sciences Center at Houston, Houston, Texas
| | - Val J Watts
- Department of Medicinal Chemistry and Molecular Pharmacology, Purdue University, West Lafayette, Indiana
- Purdue Institute for Drug Discovery, Purdue University, West Lafayette, Indiana
- Purdue Institute for Integrative Neuroscience, Purdue University, West Lafayette, Indiana
| | - Rennolds S Ostrom
- Department of Biomedical and Pharmaceutical Sciences, Chapman University School of Pharmacy, Irvine, California
| |
Collapse
|
7
|
Huang SK, Almurad O, Pejana RJ, Morrison ZA, Pandey A, Picard LP, Nitz M, Sljoka A, Prosser RS. Allosteric modulation of the adenosine A 2A receptor by cholesterol. eLife 2022; 11:e73901. [PMID: 34986091 PMCID: PMC8730723 DOI: 10.7554/elife.73901] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2021] [Accepted: 12/23/2021] [Indexed: 12/18/2022] Open
Abstract
Cholesterol is a major component of the cell membrane and commonly regulates membrane protein function. Here, we investigate how cholesterol modulates the conformational equilibria and signaling of the adenosine A2A receptor (A2AR) in reconstituted phospholipid nanodiscs. This model system conveniently excludes possible effects arising from cholesterol-induced phase separation or receptor oligomerization and focuses on the question of allostery. GTP hydrolysis assays show that cholesterol weakly enhances the basal signaling of A2AR while decreasing the agonist EC50. Fluorine nuclear magnetic resonance (19F NMR) spectroscopy shows that this enhancement arises from an increase in the receptor's active state population and a G-protein-bound precoupled state. 19F NMR of fluorinated cholesterol analogs reveals transient interactions with A2AR, indicating a lack of high-affinity binding or direct allosteric modulation. The combined results suggest that the observed allosteric effects are largely indirect and originate from cholesterol-mediated changes in membrane properties, as shown by membrane fluidity measurements and high-pressure NMR.
Collapse
Affiliation(s)
- Shuya Kate Huang
- Department of Chemistry, University of TorontoTorontoCanada
- Department of Chemical and Physical Sciences, University of Toronto MississaugaMississaugaCanada
| | - Omar Almurad
- Department of Chemistry, University of TorontoTorontoCanada
- Department of Chemical and Physical Sciences, University of Toronto MississaugaMississaugaCanada
| | - Reizel J Pejana
- Department of Chemistry, University of TorontoTorontoCanada
- Department of Chemical and Physical Sciences, University of Toronto MississaugaMississaugaCanada
| | | | - Aditya Pandey
- Department of Chemistry, University of TorontoTorontoCanada
- Department of Chemical and Physical Sciences, University of Toronto MississaugaMississaugaCanada
| | - Louis-Philippe Picard
- Department of Chemistry, University of TorontoTorontoCanada
- Department of Chemical and Physical Sciences, University of Toronto MississaugaMississaugaCanada
| | - Mark Nitz
- Department of Chemistry, University of TorontoTorontoCanada
| | - Adnan Sljoka
- RIKEN Center for Advanced Intelligence ProjectTokyoJapan
- York University, Department of ChemistryTorontoCanada
| | - R Scott Prosser
- Department of Chemistry, University of TorontoTorontoCanada
- Department of Chemical and Physical Sciences, University of Toronto MississaugaMississaugaCanada
- Department of Biochemistry, University of TorontoTorontoCanada
| |
Collapse
|
8
|
Agarwal SR, Sherpa RT, Moshal KS, Harvey RD. Compartmentalized cAMP signaling in cardiac ventricular myocytes. Cell Signal 2022; 89:110172. [PMID: 34687901 PMCID: PMC8602782 DOI: 10.1016/j.cellsig.2021.110172] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2021] [Revised: 10/15/2021] [Accepted: 10/17/2021] [Indexed: 01/03/2023]
Abstract
Activation of different receptors that act by generating the common second messenger cyclic adenosine monophosphate (cAMP) can elicit distinct functional responses in cardiac myocytes. Selectively sequestering cAMP activity to discrete intracellular microdomains is considered essential for generating receptor-specific responses. The processes that control this aspect of compartmentalized cAMP signaling, however, are not completely clear. Over the years, technological innovations have provided critical breakthroughs in advancing our understanding of the mechanisms underlying cAMP compartmentation. Some of the factors identified include localized production of cAMP by differential distribution of receptors, localized breakdown of this second messenger by targeted distribution of phosphodiesterase enzymes, and limited diffusion of cAMP by protein kinase A (PKA)-dependent buffering or physically restricted barriers. The aim of this review is to provide a discussion of our current knowledge and highlight some of the gaps that still exist in the field of cAMP compartmentation in cardiac myocytes.
Collapse
|
9
|
Maric D, Paterek A, Delaunay M, López IP, Arambasic M, Diviani D. A-Kinase Anchoring Protein 2 Promotes Protection against Myocardial Infarction. Cells 2021; 10:2861. [PMID: 34831084 PMCID: PMC8616452 DOI: 10.3390/cells10112861] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2021] [Revised: 10/20/2021] [Accepted: 10/21/2021] [Indexed: 12/25/2022] Open
Abstract
Myocardial infarction (MI) is a leading cause of maladaptive cardiac remodeling and heart failure. In the damaged heart, loss of function is mainly due to cardiomyocyte death and remodeling of the cardiac tissue. The current study shows that A-kinase anchoring protein 2 (AKAP2) orchestrates cellular processes favoring cardioprotection in infarcted hearts. Induction of AKAP2 knockout (KO) in cardiomyocytes of adult mice increases infarct size and exacerbates cardiac dysfunction after MI, as visualized by increased left ventricular dilation and reduced fractional shortening and ejection fraction. In cardiomyocytes, AKAP2 forms a signaling complex with PKA and the steroid receptor co-activator 3 (Src3). Upon activation of cAMP signaling, the AKAP2/PKA/Src3 complex favors PKA-mediated phosphorylation and activation of estrogen receptor α (ERα). This results in the upregulation of ER-dependent genes involved in protection against apoptosis and angiogenesis, including Bcl2 and the vascular endothelial growth factor a (VEGFa). In line with these findings, cardiomyocyte-specific AKAP2 KO reduces Bcl2 and VEGFa expression, increases myocardial apoptosis and impairs the formation of new blood vessels in infarcted hearts. Collectively, our findings suggest that AKAP2 organizes a transcriptional complex that mediates pro-angiogenic and anti-apoptotic responses that protect infarcted hearts.
Collapse
Affiliation(s)
- Darko Maric
- Department of Biomedical Sciences, Faculty of Biology and Medicine, University of Lausanne, 1011 Lausanne, Switzerland; (D.M.); (A.P.); (M.D.); (I.P.L.); (M.A.)
- Section of Medicine, Department of Endocrinology, Metabolism and Cardiovascular System, University of Fribourg, 1700 Fribourg, Switzerland
| | - Aleksandra Paterek
- Department of Biomedical Sciences, Faculty of Biology and Medicine, University of Lausanne, 1011 Lausanne, Switzerland; (D.M.); (A.P.); (M.D.); (I.P.L.); (M.A.)
| | - Marion Delaunay
- Department of Biomedical Sciences, Faculty of Biology and Medicine, University of Lausanne, 1011 Lausanne, Switzerland; (D.M.); (A.P.); (M.D.); (I.P.L.); (M.A.)
| | - Irene Pérez López
- Department of Biomedical Sciences, Faculty of Biology and Medicine, University of Lausanne, 1011 Lausanne, Switzerland; (D.M.); (A.P.); (M.D.); (I.P.L.); (M.A.)
| | - Miroslav Arambasic
- Department of Biomedical Sciences, Faculty of Biology and Medicine, University of Lausanne, 1011 Lausanne, Switzerland; (D.M.); (A.P.); (M.D.); (I.P.L.); (M.A.)
| | - Dario Diviani
- Department of Biomedical Sciences, Faculty of Biology and Medicine, University of Lausanne, 1011 Lausanne, Switzerland; (D.M.); (A.P.); (M.D.); (I.P.L.); (M.A.)
| |
Collapse
|
10
|
Harvey RD, Clancy CE. Mechanisms of cAMP compartmentation in cardiac myocytes: experimental and computational approaches to understanding. J Physiol 2021; 599:4527-4544. [PMID: 34510451 DOI: 10.1113/jp280801] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2021] [Accepted: 09/07/2021] [Indexed: 01/04/2023] Open
Abstract
The small diffusible second messenger 3',5'-cyclic adenosine monophosphate (cAMP) is found in virtually every cell in our bodies, where it mediates responses to a variety of different G protein coupled receptors (GPCRs). In the heart, cAMP plays a critical role in regulating many different aspects of cardiac myocyte function, including gene transcription, cell metabolism, and excitation-contraction coupling. Yet, not all GPCRs that stimulate cAMP production elicit the same responses. Subcellular compartmentation of cAMP is essential to explain how different receptors can utilize the same diffusible second messenger to elicit unique functional responses. However, the mechanisms contributing to this behaviour and its significance in producing physiological and pathological responses are incompletely understood. Mathematical modelling has played an essential role in gaining insight into these questions. This review discusses what we currently know about cAMP compartmentation in cardiac myocytes and questions that are yet to be answered.
Collapse
Affiliation(s)
- Robert D Harvey
- Department of Pharmacology, University of Nevada, Reno, NV, 89557, USA
| | - Colleen E Clancy
- Department of Physiology and Membrane Biology, University of California-Davis, Davis, CA, 95616, USA
| |
Collapse
|
11
|
Chen JJ, Fan Y, Boehning D. Regulation of Dynamic Protein S-Acylation. Front Mol Biosci 2021; 8:656440. [PMID: 33981723 PMCID: PMC8107437 DOI: 10.3389/fmolb.2021.656440] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2021] [Accepted: 02/16/2021] [Indexed: 12/20/2022] Open
Abstract
Protein S-acylation is the reversible addition of fatty acids to the cysteine residues of target proteins. It regulates multiple aspects of protein function, including the localization to membranes, intracellular trafficking, protein interactions, protein stability, and protein conformation. This process is regulated by palmitoyl acyltransferases that have the conserved amino acid sequence DHHC at their active site. Although they have conserved catalytic cores, DHHC enzymes vary in their protein substrate selection, lipid substrate preference, and regulatory mechanisms. Alterations in DHHC enzyme function are associated with many human diseases, including cancers and neurological conditions. The removal of fatty acids from acylated cysteine residues is catalyzed by acyl protein thioesterases. Notably, S-acylation is now known to be a highly dynamic process, and plays crucial roles in signaling transduction in various cell types. In this review, we will explore the recent findings on protein S-acylation, the enzymatic regulation of this process, and discuss examples of dynamic S-acylation.
Collapse
|
12
|
Receptor tyrosine kinases activate heterotrimeric G proteins via phosphorylation within the interdomain cleft of Gαi. Proc Natl Acad Sci U S A 2020; 117:28763-28774. [PMID: 33139573 DOI: 10.1073/pnas.2004699117] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023] Open
Abstract
The molecular mechanisms by which receptor tyrosine kinases (RTKs) and heterotrimeric G proteins, two major signaling hubs in eukaryotes, independently relay signals across the plasma membrane have been extensively characterized. How these hubs cross-talk has been a long-standing question, but answers remain elusive. Using linear ion-trap mass spectrometry in combination with biochemical, cellular, and computational approaches, we unravel a mechanism of activation of heterotrimeric G proteins by RTKs and chart the key steps that mediate such activation. Upon growth factor stimulation, the guanine-nucleotide exchange modulator dissociates Gαi•βγ trimers, scaffolds monomeric Gαi with RTKs, and facilitates the phosphorylation on two tyrosines located within the interdomain cleft of Gαi. Phosphorylation triggers the activation of Gαi and inhibits second messengers (cAMP). Tumor-associated mutants reveal how constitutive activation of this pathway impacts cell's decision to "go" vs. "grow." These insights define a tyrosine-based G protein signaling paradigm and reveal its importance in eukaryotes.
Collapse
|
13
|
Plouffe B, Thomsen ARB, Irannejad R. Emerging Role of Compartmentalized G Protein-Coupled Receptor Signaling in the Cardiovascular Field. ACS Pharmacol Transl Sci 2020; 3:221-236. [PMID: 32296764 PMCID: PMC7155194 DOI: 10.1021/acsptsci.0c00006] [Citation(s) in RCA: 29] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2020] [Indexed: 02/06/2023]
Abstract
G protein-coupled receptors (GPCRs) are cell surface receptors that for many years have been considered to function exclusively at the plasma membrane, where they bind to extracellular ligands and activate G protein signaling cascades. According to the conventional model, these signaling events are rapidly terminated by β-arrestin (β-arr) recruitment to the activated GPCR resulting in signal desensitization and receptor internalization. However, during the past decade, emerging evidence suggest that many GPCRs can continue to activate G proteins from intracellular compartments after they have been internalized. G protein signaling from intracellular compartments is in general more sustained compared to G protein signaling at the plasma membrane. Notably, the particular location closer to the nucleus is beneficial for selective cellular functions such as regulation of gene transcription. Here, we review key GPCRs that undergo compartmentalized G protein signaling and discuss molecular considerations and requirements for this signaling to occur. Our main focus will be on receptors involved in the regulation of important physiological and pathological cardiovascular functions. We also discuss how sustained G protein activation from intracellular compartments may be involved in cellular functions that are distinct from functions regulated by plasma membrane G protein signaling, and the corresponding significance in cardiovascular physiology.
Collapse
Affiliation(s)
- Bianca Plouffe
- Wellcome-Wolfson Institute for Experimental Medicine, Queen's University Belfast, Belfast BT9 7BL, United Kingdom
| | - Alex R B Thomsen
- Department of Basic Science and Craniofacial Biology, NYU College of Dentistry, New York, New York 10010, United States
| | - Roshanak Irannejad
- Department of Biochemistry and Biophysics, Cardiovascular Research Institute, University of California, San Francisco, California 94158, United States
| |
Collapse
|
14
|
The Role of Cyclic AMP Signaling in Cardiac Fibrosis. Cells 2019; 9:cells9010069. [PMID: 31888098 PMCID: PMC7016856 DOI: 10.3390/cells9010069] [Citation(s) in RCA: 44] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2019] [Revised: 12/23/2019] [Accepted: 12/24/2019] [Indexed: 12/18/2022] Open
Abstract
Myocardial stress and injury invariably promote remodeling of the cardiac tissue, which is associated with cardiomyocyte death and development of fibrosis. The fibrotic process is initially triggered by the differentiation of resident cardiac fibroblasts into myofibroblasts. These activated fibroblasts display increased proliferative capacity and secrete large amounts of extracellular matrix. Uncontrolled myofibroblast activation can thus promote heart stiffness, cardiac dysfunction, arrhythmias, and progression to heart failure. Despite the well-established role of myofibroblasts in mediating cardiac disease, our current knowledge on how signaling pathways promoting fibrosis are regulated and coordinated in this cell type is largely incomplete. In this respect, cyclic adenosine monophosphate (cAMP) signaling acts as a major modulator of fibrotic responses activated in fibroblasts of injured or stressed hearts. In particular, accumulating evidence now suggests that upstream cAMP modulators including G protein-coupled receptors, adenylyl cyclases (ACs), and phosphodiesterases (PDEs); downstream cAMP effectors such as protein kinase A (PKA) and the guanine nucleotide exchange factor Epac; and cAMP signaling organizers such as A-kinase anchoring proteins (AKAPs) modulate a variety of fundamental cellular processes involved in myocardial fibrosis including myofibroblast differentiation, proliferation, collagen secretion, and invasiveness. The current review will discuss recent advances highlighting the role of cAMP and AKAP-mediated signaling in regulating pathophysiological responses controlling cardiac fibrosis.
Collapse
|
15
|
Chen JJ, Marsden AN, Scott CA, Akimzhanov AM, Boehning D. DHHC5 Mediates β-Adrenergic Signaling in Cardiomyocytes by Targeting Gα Proteins. Biophys J 2019; 118:826-835. [PMID: 31547976 PMCID: PMC7036738 DOI: 10.1016/j.bpj.2019.08.018] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2019] [Revised: 08/14/2019] [Accepted: 08/19/2019] [Indexed: 02/06/2023] Open
Abstract
S-palmitoylation is a reversible posttranslational modification that plays an important role in regulating protein localization, trafficking, and stability. Recent studies have shown that some proteins undergo extremely rapid palmitoylation/depalmitoylation cycles after cellular stimulation supporting a direct signaling role for this posttranslational modification. Here, we investigated whether β-adrenergic stimulation of cardiomyocytes led to stimulus-dependent palmitoylation of downstream signaling proteins. We found that β-adrenergic stimulation led to rapidly increased Gαs and Gαi palmitoylation. The kinetics of palmitoylation was temporally consistent with the downstream production of cAMP and contractile responses. We identified the plasma membrane-localized palmitoyl acyltransferase DHHC5 as an important mediator of the stimulus-dependent palmitoylation in cardiomyocytes. Knockdown of DHHC5 showed that this enzyme is necessary for palmitoylation of Gαs, Gαi, and functional responses downstream of β-adrenergic stimulation. A palmitoylation assay with purified components revealed that Gαs and Gαi are direct substrates of DHHC5. Finally, we provided evidence that the C-terminal tail of DHHC5 can be palmitoylated in response to stimulation and such modification is important for its dynamic localization and function in the plasma membrane. Our results reveal that DHHC5 is a central regulator of signaling downstream of β-adrenergic receptors in cardiomyocytes.
Collapse
Affiliation(s)
- Jessica J Chen
- Department of Biochemistry and Molecular Biology, McGovern Medical School at UTHealth, Houston, Texas
| | - Autumn N Marsden
- Department of Biochemistry and Molecular Biology, McGovern Medical School at UTHealth, Houston, Texas
| | - C Anthony Scott
- Department of Pediatrics, Baylor College of Medicine, Houston, Texas
| | - Askar M Akimzhanov
- Department of Biochemistry and Molecular Biology, McGovern Medical School at UTHealth, Houston, Texas
| | - Darren Boehning
- Department of Biomedical Sciences, Cooper Medical School of Rowan University, Camden, New Jersey.
| |
Collapse
|
16
|
Abstract
Lipid microenvironments in the plasma membrane are known to influence many signal transduction pathways. Several of those pathways are critical for both the etiology and treatment of depression. Further, several signaling proteins are modified, covalently, by lipids, a process that alters their interface with the microenvironments mentioned above. This review presents a brief discussion of the interface of the above elements as well as a discussion about the participation of lipids and lipid moieties in the action of antidepressants.
Collapse
Affiliation(s)
- Nathan H Wray
- University of Illinois College of Medicine, Department of Physiology & Biophysics, Chicago, IL, United States; The Graduate Program in Neuroscience, Chicago, IL, United States
| | - Mark M Rasenick
- University of Illinois College of Medicine, Department of Physiology & Biophysics, Chicago, IL, United States; The Graduate Program in Neuroscience, Chicago, IL, United States; Department of Psychiatry, Chicago, IL, United States; The Jesse Brown VAMC, Chicago, IL, United States.
| |
Collapse
|
17
|
Lingemann M, McCarty T, Liu X, Buchholz UJ, Surman S, Martin SE, Collins PL, Munir S. The alpha-1 subunit of the Na+,K+-ATPase (ATP1A1) is required for macropinocytic entry of respiratory syncytial virus (RSV) in human respiratory epithelial cells. PLoS Pathog 2019; 15:e1007963. [PMID: 31381610 PMCID: PMC6695199 DOI: 10.1371/journal.ppat.1007963] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2019] [Revised: 08/15/2019] [Accepted: 07/05/2019] [Indexed: 01/07/2023] Open
Abstract
Human respiratory syncytial virus (RSV) is the leading viral cause of acute pediatric lower respiratory tract infections worldwide, with no available vaccine or effective antiviral drug. To gain insight into virus-host interactions, we performed a genome-wide siRNA screen. The expression of over 20,000 cellular genes was individually knocked down in human airway epithelial A549 cells, followed by infection with RSV expressing green fluorescent protein (GFP). Knockdown of expression of the cellular ATP1A1 protein, which is the major subunit of the Na+,K+-ATPase of the plasma membrane, had one of the strongest inhibitory effects on GFP expression and viral titer. Inhibition was not observed for vesicular stomatitis virus, indicating that it was RSV-specific rather than a general effect. ATP1A1 formed clusters in the plasma membrane very early following RSV infection, which was independent of replication but dependent on the attachment glycoprotein G. RSV also triggered activation of ATP1A1, resulting in signaling by c-Src-kinase activity that transactivated epidermal growth factor receptor (EGFR) by Tyr845 phosphorylation. ATP1A1 signaling and activation of both c-Src and EGFR were found to be required for efficient RSV uptake. Signaling events downstream of EGFR culminated in the formation of macropinosomes. There was extensive uptake of RSV virions into macropinosomes at the beginning of infection, suggesting that this is a major route of RSV uptake, with fusion presumably occurring in the macropinosomes rather than at the plasma membrane. Important findings were validated in primary human small airway epithelial cells (HSAEC). In A549 cells and HSAEC, RSV uptake could be inhibited by the cardiotonic steroid ouabain and the digitoxigenin derivative PST2238 (rostafuroxin) that bind specifically to the ATP1A1 extracellular domain and block RSV-triggered EGFR Tyr845 phosphorylation. In conclusion, we identified ATP1A1 as a host protein essential for macropinocytic entry of RSV into respiratory epithelial cells, and identified PST2238 as a potential anti-RSV drug. RSV continues to be the most important viral cause of severe bronchiolitis and pneumonia in infants and young children, and also has a substantial impact in the elderly. It is estimated to claim the lives of ~118,000 children under five years of age annually. No vaccine or antiviral drug suitable for general use is available. The involvement of host factors in RSV infection and replication is not well understood, but this knowledge might lead to intervention strategies to prevent infection. Using a genome-wide siRNA screen to knock down the expression of over 20,000 individual cellular genes, we identified ATP1A1, the major subunit of the Na+,K+-ATPase, as an important host protein for RSV entry. We showed that ATP1A1 activation by RSV resulted in transactivation of EGFR by Src-kinase activity, resulting in the uptake of RSV particles into the host cell through macropinocytosis. We also showed that the cardiotonic steroid ouabain and the synthetic digitoxigenin derivative PST2238, which bind specifically to the extracellular domain of ATP1A1, significantly reduced RSV entry. Taken together, we describe a novel ATP1A1-enabled mechanism used by RSV to enter the host cell, and describe candidate antiviral drugs that block this entry.
Collapse
Affiliation(s)
- Matthias Lingemann
- RNA Viruses Section, Laboratory of Infectious Diseases, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland, United States of America
- Institut für Mikrobiologie, Technische Universität Braunschweig, Braunschweig, Germany
| | - Thomas McCarty
- RNA Viruses Section, Laboratory of Infectious Diseases, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland, United States of America
| | - Xueqiao Liu
- RNA Viruses Section, Laboratory of Infectious Diseases, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland, United States of America
| | - Ursula J. Buchholz
- RNA Viruses Section, Laboratory of Infectious Diseases, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland, United States of America
| | - Sonja Surman
- RNA Viruses Section, Laboratory of Infectious Diseases, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland, United States of America
| | - Scott E. Martin
- Division of Pre-Clinical Innovation, National Center for Advancing Translational Sciences, Rockville, Maryland, United States of America
| | - Peter L. Collins
- RNA Viruses Section, Laboratory of Infectious Diseases, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland, United States of America
| | - Shirin Munir
- RNA Viruses Section, Laboratory of Infectious Diseases, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland, United States of America
- * E-mail:
| |
Collapse
|
18
|
Abstract
G protein-coupled receptors (GPCRs) are critical cellular sensors that mediate numerous physiological processes. In the heart, multiple GPCRs are expressed on various cell types, where they coordinate to regulate cardiac function by modulating critical processes such as contractility and blood flow. Under pathological settings, these receptors undergo aberrant changes in expression levels, localization and capacity to couple to downstream signalling pathways. Conventional therapies for heart failure work by targeting GPCRs, such as β-adrenergic receptor and angiotensin II receptor antagonists. Although these treatments have improved patient survival, heart failure remains one of the leading causes of mortality worldwide. GPCR kinases (GRKs) are responsible for GPCR phosphorylation and, therefore, desensitization and downregulation of GPCRs. In this Review, we discuss the GPCR signalling pathways and the GRKs involved in the pathophysiology of heart disease. Given that increased expression and activity of GRK2 and GRK5 contribute to the loss of contractile reserve in the stressed and failing heart, inhibition of overactive GRKs has been proposed as a novel therapeutic approach to treat heart failure.
Collapse
|
19
|
Agarwal SR, Fiore C, Miyashiro K, Ostrom RS, Harvey RD. Effect of Adenylyl Cyclase Type 6 on Localized Production of cAMP by β-2 Adrenoceptors in Human Airway Smooth-Muscle Cells. J Pharmacol Exp Ther 2019; 370:104-110. [PMID: 31068382 DOI: 10.1124/jpet.119.256594] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2019] [Accepted: 05/02/2019] [Indexed: 12/17/2022] Open
Abstract
β 2-Adrenoceptors (β 2ARs) are concentrated in caveolar lipid raft domains of the plasma membrane in airway smooth-muscle (ASM) cells, along with adenylyl cyclase type 6 (AC6). This is believed to contribute to how these receptors can selectively regulate certain types of cAMP-dependent responses in these cells. The goal of the present study was to test the hypothesis that β 2AR production of cAMP is localized to specific subcellular compartments using fluorescence resonance energy transfer-based cAMP biosensors targeted to different microdomains in human ASM cells. Epac2-MyrPalm and Epac2-CAAX biosensors were used to measure responses associated with lipid raft and nonraft regions of the plasma membrane, respectively. Activation of β 2ARs with isoproterenol produced cAMP responses that are most readily detected in lipid raft domains. Furthermore, overexpression of AC6 somewhat paradoxically inhibited β 2AR production of cAMP in lipid raft domains without affecting β 2AR responses detected in other subcellular locations or cAMP responses to EP2 prostaglandin receptor activation, which were confined primarily to nonraft domains of the plasma membrane. The inhibitory effect of overexpressing AC6 was blocked by inhibition of phosphodiesterase type 4 (PDE4) activity with rolipram, inhibition of protein kinase A (PKA) activity with H89, and inhibition of A kinase anchoring protein (AKAP) interactions with the peptide inhibitor Ht31. These results support the idea that overexpression of AC6 leads to enhanced feedback activation of PDE4 via phosphorylation by PKA that is part of an AKAP-dependent signaling complex. This provides insight into the molecular basis for localized regulation of cAMP signaling in human ASM cells.
Collapse
Affiliation(s)
- Shailesh R Agarwal
- Department of Pharmacology, University of Nevada, Reno School of Medicine, Reno, Nevada (S.R.A., C.F., K.M., R.D.H.); and Department of Biomedical and Pharmaceutical Sciences, Chapman University School of Pharmacy, Irvine, California (R.S.O.)
| | - Chase Fiore
- Department of Pharmacology, University of Nevada, Reno School of Medicine, Reno, Nevada (S.R.A., C.F., K.M., R.D.H.); and Department of Biomedical and Pharmaceutical Sciences, Chapman University School of Pharmacy, Irvine, California (R.S.O.)
| | - Kathryn Miyashiro
- Department of Pharmacology, University of Nevada, Reno School of Medicine, Reno, Nevada (S.R.A., C.F., K.M., R.D.H.); and Department of Biomedical and Pharmaceutical Sciences, Chapman University School of Pharmacy, Irvine, California (R.S.O.)
| | - Rennolds S Ostrom
- Department of Pharmacology, University of Nevada, Reno School of Medicine, Reno, Nevada (S.R.A., C.F., K.M., R.D.H.); and Department of Biomedical and Pharmaceutical Sciences, Chapman University School of Pharmacy, Irvine, California (R.S.O.)
| | - Robert D Harvey
- Department of Pharmacology, University of Nevada, Reno School of Medicine, Reno, Nevada (S.R.A., C.F., K.M., R.D.H.); and Department of Biomedical and Pharmaceutical Sciences, Chapman University School of Pharmacy, Irvine, California (R.S.O.)
| |
Collapse
|
20
|
Cosson MV, Hiis HG, Moltzau LR, Levy FO, Krobert KA. Knockout of adenylyl cyclase isoform 5 or 6 differentially modifies the β 1-adrenoceptor-mediated inotropic response. J Mol Cell Cardiol 2019; 131:132-145. [PMID: 31009605 DOI: 10.1016/j.yjmcc.2019.04.017] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/07/2019] [Revised: 04/15/2019] [Accepted: 04/17/2019] [Indexed: 12/15/2022]
Abstract
Although only β2-adrenergic receptors (βAR) dually couple with stimulatory G protein (Gs) and inhibitory G protein (Gi), inactivation of Gi enhances both β1AR and β2AR responsiveness. We hypothesize that Gi restrains spontaneous adenylyl cyclase (AC) activity independent of receptor activation. Subcellular localization of the AC5/6 subtypes varies contributing to the compartmentation of βAR signaling. The primary objectives were to determine: (1) if β1AR-mediated inotropic responses were dependent upon either AC5 or AC6; (2) if intrinsic Gi inhibition is AC subtype selective and (3) the role of phosphodiesterases (PDE) 3/4 to regulate β1AR responsiveness. β1AR-mediated increases in contractile force and cAMP accumulation in cardiomyocytes were measured from wild type, AC5 and AC6 knockout (KO) mice, with or without pertussis toxin (PTX) pretreatment to inactivate Gi and/or after selective inhibition of PDEs 3/4. Noradrenaline potency at β1ARs was increased in AC6 KO. PDE4 inhibition increased noradrenaline potency in wild type and AC5 KO, but not AC6 KO. PTX increased noradrenaline potency only in wild type but increased the maximal β1AR response in all mouse strains. PDE3 inhibition increased noradrenaline potency only in AC5 KO that was treated prior with PTX. β1AR-evoked cAMP accumulation was increased more by PDE4 inhibition than PDE3 inhibition in wild type and AC5 KO that was amplified by Gi inhibition. These data indicate that β1AR-mediated inotropic responses are not dependent upon either AC5 or AC6 alone. Inactivation of Gi enhanced β1AR-mediated inotropic responses despite not coupling to Gi, consistent with Gi exerting a tonic receptor independent inhibition upon AC5/6. PDE4 seems the primary regulator of β1AR signaling through AC6 in wild type. AC6 KO results in a reorganization of β1AR compartmentation characterized by signaling through AC5 regulated by Gi, PDE3 and PDE4 that maintains normal contractile function.
Collapse
Affiliation(s)
- Marie-Victoire Cosson
- Department of Pharmacology and Center for Heart Failure Research, Institute of Clinical Medicine, Faculty of Medicine, University of Oslo and Oslo University Hospital, Oslo, Norway
| | - Halvard Gautefall Hiis
- Department of Pharmacology and Center for Heart Failure Research, Institute of Clinical Medicine, Faculty of Medicine, University of Oslo and Oslo University Hospital, Oslo, Norway
| | - Lise Román Moltzau
- Department of Pharmacology and Center for Heart Failure Research, Institute of Clinical Medicine, Faculty of Medicine, University of Oslo and Oslo University Hospital, Oslo, Norway
| | - Finn Olav Levy
- Department of Pharmacology and Center for Heart Failure Research, Institute of Clinical Medicine, Faculty of Medicine, University of Oslo and Oslo University Hospital, Oslo, Norway.
| | - Kurt Allen Krobert
- Department of Pharmacology and Center for Heart Failure Research, Institute of Clinical Medicine, Faculty of Medicine, University of Oslo and Oslo University Hospital, Oslo, Norway
| |
Collapse
|
21
|
Liu JJ, Hezghia A, Shaikh SR, Cenido JF, Stark RE, Mann JJ, Sublette ME. Regulation of monoamine transporters and receptors by lipid microdomains: implications for depression. Neuropsychopharmacology 2018; 43:2165-2179. [PMID: 30022062 PMCID: PMC6135777 DOI: 10.1038/s41386-018-0133-6] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/21/2017] [Revised: 05/24/2018] [Accepted: 06/18/2018] [Indexed: 12/16/2022]
Abstract
Lipid microdomains ("rafts") are dynamic, nanoscale regions of the plasma membrane enriched in cholesterol and glycosphingolipids, that possess distinctive physicochemical properties including higher order than the surrounding membrane. Lipid microdomain integrity is thought to affect neurotransmitter signaling by regulating membrane-bound protein signaling. Among the proteins potentially affected are monoaminergic receptors and transporters. As dysfunction of monoaminergic neurotransmission is implicated in major depressive disorder and other neuropsychiatric conditions, interactions with lipid microdomains may be of clinical importance. This systematic review evaluates what is known about the molecular relationships of monoamine transporter and receptor regulation to lipid microdomains. The PubMed/MeSH database was searched for original studies published in English through August 2017 concerning relationships between lipid microdomains and serotonin, dopamine and norepinephrine transporters and receptors. Fifty-seven publications were identified and assessed. Strong evidence implicates lipid microdomains in the regulation of serotonin and norepinephrine transporters; serotonin 1A, 2A, 3A, and 7A receptors; and dopamine D1 and β2 adrenergic receptors. Results were conflicting or more complex regarding lipid microdomain associations with the dopamine transporter, D2, D3, and D5 receptors; and negative with respect to β1 adrenergic receptors. Indirect evidence suggests that antidepressants, lipid-lowering drugs, and polyunsaturated fatty acids may exert effects on depression and suicide by altering the lipid milieu, thereby affecting monoaminergic transporter and receptor signaling. The lipid composition of membrane subdomains is involved in localization and trafficking of specific monoaminergic receptors and transporters. Elucidating precise mechanisms whereby lipid microdomains modulate monoamine neurotransmission in clinical contexts can have critical implications for pharmacotherapeutic targeting.
Collapse
Affiliation(s)
- Joanne J Liu
- Department of Molecular Imaging & Neuropathology, New York State Psychiatric Institute, New York, NY, USA
- Chestnut Hill Hospital, Philadelphia, PA, USA
| | - Adrienne Hezghia
- Department of Molecular Imaging & Neuropathology, New York State Psychiatric Institute, New York, NY, USA
- Jacobs School of Medicine and Biomedical Sciences, University at Buffalo, The State University of New York, Buffalo, NY, USA
| | - Saame Raza Shaikh
- Department of Nutrition, Gillings School of Global Public Health, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA
| | - Joshua F Cenido
- Department of Molecular Imaging & Neuropathology, New York State Psychiatric Institute, New York, NY, USA
- Department of Psychiatry, Charles R. Drew University of Medicine and Science, Los Angeles, CA, USA
| | - Ruth E Stark
- Department of Chemistry and Biochemistry and CUNY Institute for Macromolecular Assemblies, The City College of New York, New York, NY, USA
- Ph.D. Program in Biochemistry, The Graduate Center of the City University of New York, New York, NY, USA
| | - J John Mann
- Department of Molecular Imaging & Neuropathology, New York State Psychiatric Institute, New York, NY, USA
- Department of Psychiatry, Columbia University, New York, NY, USA
- Department of Radiology, Columbia University, New York, NY, USA
| | - M Elizabeth Sublette
- Department of Molecular Imaging & Neuropathology, New York State Psychiatric Institute, New York, NY, USA.
- Department of Psychiatry, Columbia University, New York, NY, USA.
| |
Collapse
|
22
|
Murakami E, Cheng J, Gysel K, Bozsoki Z, Kawaharada Y, Hjuler CT, Sørensen KK, Tao K, Kelly S, Venice F, Genre A, Thygesen MB, de Jong N, Vinther M, Jensen DB, Jensen KJ, Blaise M, Madsen LH, Andersen KR, Stougaard J, Radutoiu S. Epidermal LysM receptor ensures robust symbiotic signalling in Lotus japonicus. eLife 2018; 7:e33506. [PMID: 29957177 PMCID: PMC6025957 DOI: 10.7554/elife.33506] [Citation(s) in RCA: 41] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2017] [Accepted: 06/05/2018] [Indexed: 02/04/2023] Open
Abstract
Recognition of Nod factors by LysM receptors is crucial for nitrogen-fixing symbiosis in most legumes. The large families of LysM receptors in legumes suggest concerted functions, yet only NFR1 and NFR5 and their closest homologs are known to be required. Here we show that an epidermal LysM receptor (NFRe), ensures robust signalling in L. japonicus. Mutants of Nfre react to Nod factors with increased calcium spiking interval, reduced transcriptional response and fewer nodules in the presence of rhizobia. NFRe has an active kinase capable of phosphorylating NFR5, which in turn, controls NFRe downstream signalling. Our findings provide evidence for a more complex Nod factor signalling mechanism than previously anticipated. The spatio-temporal interplay between Nfre and Nfr1, and their divergent signalling through distinct kinases suggests the presence of an NFRe-mediated idling state keeping the epidermal cells of the expanding root system attuned to rhizobia.
Collapse
Affiliation(s)
- Eiichi Murakami
- Department of Molecular Biology and GeneticsAarhus UniversityAarhusDenmark
| | - Jeryl Cheng
- Department of Molecular Biology and GeneticsAarhus UniversityAarhusDenmark
| | - Kira Gysel
- Department of Molecular Biology and GeneticsAarhus UniversityAarhusDenmark
| | - Zoltan Bozsoki
- Department of Molecular Biology and GeneticsAarhus UniversityAarhusDenmark
| | | | | | | | - Ke Tao
- Department of Molecular Biology and GeneticsAarhus UniversityAarhusDenmark
| | - Simon Kelly
- Department of Molecular Biology and GeneticsAarhus UniversityAarhusDenmark
| | - Francesco Venice
- Department of Life Sciences and Systems BiologyUniversity of TorinoTorinoItaly
| | - Andrea Genre
- Department of Life Sciences and Systems BiologyUniversity of TorinoTorinoItaly
| | | | - Noor de Jong
- Department of Molecular Biology and GeneticsAarhus UniversityAarhusDenmark
| | - Maria Vinther
- Department of Molecular Biology and GeneticsAarhus UniversityAarhusDenmark
| | | | | | - Michael Blaise
- Department of Molecular Biology and GeneticsAarhus UniversityAarhusDenmark
| | | | | | - Jens Stougaard
- Department of Molecular Biology and GeneticsAarhus UniversityAarhusDenmark
| | - Simona Radutoiu
- Department of Molecular Biology and GeneticsAarhus UniversityAarhusDenmark
| |
Collapse
|
23
|
Anwar MA, Samaha AA, Baydoun S, Iratni R, Eid AH. Rhus coriaria L. (Sumac) Evokes Endothelium-Dependent Vasorelaxation of Rat Aorta: Involvement of the cAMP and cGMP Pathways. Front Pharmacol 2018; 9:688. [PMID: 30002626 PMCID: PMC6031713 DOI: 10.3389/fphar.2018.00688] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2017] [Accepted: 06/07/2018] [Indexed: 12/13/2022] Open
Abstract
Rhus coriaria L. (sumac) is widely used in traditional remedies and cuisine of countries of the Mediterranean as well as Central and South-West Asia. Administration of sumac to experimental models and patients with diverse pathological conditions generates multi-faceted propitious effects, including the quality as a vasodilator. Together, the effects are concertedly channeled toward cardiovasobolic protection. However, there is paucity of data on the mechanism of action for sumac’s vasodilatory effect, an attribute which is considered to be advantageous for unhealthy circulatory system. Accordingly, we sought to determine the mechanisms by which sumac elicits its vasorelaxatory effects. We deciphered the signaling networks by application of a range of pharmacological inhibitors, biochemical assays and including the quantification of cyclic nucleotide monophosphates. Herein, we provide evidence that an ethanolic extract of sumac fruit, dose-dependently, relaxes rat isolated aorta. The mechanistic effect is achieved via stimulation of multiple transducers namely PI3-K/Akt, eNOS, NO, guanylyl cyclase, cGMP, and PKG. Interestingly, the arachidonic acid pathway (cyclooxygenases), adenylyl cyclase/cAMP and ATP-dependent potassium channels appear to partake in this sumac-orchestrated attenuation of vascular tone. Clearly, our data support the favorable potential cardio-vasculoprotective action of sumac.
Collapse
Affiliation(s)
- Mohammad A Anwar
- Department of Biological and Environmental Sciences, College of Arts and Sciences, Qatar University, Doha, Qatar
| | - Ali A Samaha
- Department of Biomedical Sciences, Lebanese International University, Beirut, Lebanon.,Faculty of Public Health IV, Lebanese University, Beirut, Lebanon
| | - Safaa Baydoun
- Research Center for Environment and Development, Beirut Arab University, Beirut, Lebanon
| | - Rabah Iratni
- Department of Biology, College of Science, United Arab Emirates University, Al Ain, United Arab Emirates
| | - Ali H Eid
- Department of Biological and Environmental Sciences, College of Arts and Sciences, Qatar University, Doha, Qatar.,Department of Pharmacology and Toxicology, Faculty of Medicine, American University of Beirut, Beirut, Lebanon
| |
Collapse
|
24
|
Agarwal SR, Gratwohl J, Cozad M, Yang PC, Clancy CE, Harvey RD. Compartmentalized cAMP Signaling Associated With Lipid Raft and Non-raft Membrane Domains in Adult Ventricular Myocytes. Front Pharmacol 2018; 9:332. [PMID: 29740315 PMCID: PMC5925456 DOI: 10.3389/fphar.2018.00332] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2017] [Accepted: 03/21/2018] [Indexed: 11/23/2022] Open
Abstract
Aim: Confining cAMP production to discrete subcellular locations makes it possible for this ubiquitous second messenger to elicit unique functional responses. Yet, factors that determine how and where the production of this diffusible signaling molecule occurs are incompletely understood. The fluid mosaic model originally proposed that signal transduction occurs through random interactions between proteins diffusing freely throughout the plasma membrane. However, it is now known that the movement of membrane proteins is restricted, suggesting that the plasma membrane is segregated into distinct microdomains where different signaling proteins can be concentrated. In this study, we examined what role lipid raft and non-raft membrane domains play in compartmentation of cAMP signaling in adult ventricular myocytes. Methods and Results: The freely diffusible fluorescence resonance energy transfer-based biosensor Epac2-camps was used to measure global cytosolic cAMP responses, while versions of the probe targeted to lipid raft (Epac2-MyrPalm) and non-raft (Epac2-CAAX) domains were used to monitor local cAMP production near the plasma membrane. We found that β-adrenergic receptors, which are expressed in lipid raft and non-raft domains, produce cAMP responses near the plasma membrane that are distinctly different from those produced by E-type prostaglandin receptors, which are expressed exclusively in non-raft domains. We also found that there are differences in basal cAMP levels associated with lipid raft and non-raft domains, and that this can be explained by differences in basal adenylyl cyclase activity associated with each of these membrane environments. In addition, we found evidence that phosphodiesterases 2, 3, and 4 work together in regulating cAMP activity associated with both lipid raft and non-raft domains, while phosphodiesterase 3 plays a more prominent role in the bulk cytoplasmic compartment. Conclusion: These results suggest that different membrane domains contribute to the formation of distinct pools of cAMP under basal conditions as well as following receptor stimulation in adult ventricular myocytes.
Collapse
Affiliation(s)
- Shailesh R Agarwal
- Department of Pharmacology, University of Nevada, Reno, Reno, NV, United States
| | - Jackson Gratwohl
- Department of Pharmacology, University of Nevada, Reno, Reno, NV, United States
| | - Mia Cozad
- Department of Pharmacology, University of Nevada, Reno, Reno, NV, United States
| | - Pei-Chi Yang
- Department of Pharmacology, University of California, Davis, Davis, CA, United States
| | - Colleen E Clancy
- Department of Pharmacology, University of California, Davis, Davis, CA, United States
| | - Robert D Harvey
- Department of Pharmacology, University of Nevada, Reno, Reno, NV, United States
| |
Collapse
|
25
|
Johnstone TB, Agarwal SR, Harvey RD, Ostrom RS. cAMP Signaling Compartmentation: Adenylyl Cyclases as Anchors of Dynamic Signaling Complexes. Mol Pharmacol 2018; 93:270-276. [PMID: 29217670 PMCID: PMC5820540 DOI: 10.1124/mol.117.110825] [Citation(s) in RCA: 75] [Impact Index Per Article: 12.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2017] [Accepted: 12/04/2017] [Indexed: 11/22/2022] Open
Abstract
It is widely accepted that cAMP signaling is compartmentalized within cells. However, our knowledge of how receptors, cAMP signaling enzymes, effectors, and other key proteins form specific signaling complexes to regulate specific cell responses is limited. The multicomponent nature of these systems and the spatiotemporal dynamics involved as proteins interact and move within a cell make cAMP responses highly complex. Adenylyl cyclases, the enzymatic source of cAMP production, are key starting points for understanding cAMP compartments and defining the functional signaling complexes. Three basic elements are required to form a signaling compartment. First, a localized signal is generated by a G protein-coupled receptor paired to one or more of the nine different transmembrane adenylyl cyclase isoforms that generate the cAMP signal in the cytosol. The diffusion of cAMP is subsequently limited by several factors, including expression of any number of phosphodiesterases (of which there are 24 genes plus spice variants). Finally, signal response elements are differentially localized to respond to cAMP produced within each locale. A-kinase-anchoring proteins, of which there are 43 different isoforms, facilitate this by targeting protein kinase A to specific substrates. Thousands of potential combinations of these three elements are possible in any given cell type, making the characterization of cAMP signaling compartments daunting. This review will focus on what is known about how cells organize cAMP signaling components as well as identify the unknowns. We make an argument for adenylyl cyclases being central to the formation and maintenance of these signaling complexes.
Collapse
Affiliation(s)
- Timothy B Johnstone
- Department of Biomedical and Pharmaceutical Sciences, Chapman University School of Pharmacy, Irvine, California (T.B.J., R.S.O.); and Department of Pharmacology, University of Nevada, Reno School of Medicine, Reno Nevada (S.R.A., R.D.H.)
| | - Shailesh R Agarwal
- Department of Biomedical and Pharmaceutical Sciences, Chapman University School of Pharmacy, Irvine, California (T.B.J., R.S.O.); and Department of Pharmacology, University of Nevada, Reno School of Medicine, Reno Nevada (S.R.A., R.D.H.)
| | - Robert D Harvey
- Department of Biomedical and Pharmaceutical Sciences, Chapman University School of Pharmacy, Irvine, California (T.B.J., R.S.O.); and Department of Pharmacology, University of Nevada, Reno School of Medicine, Reno Nevada (S.R.A., R.D.H.)
| | - Rennolds S Ostrom
- Department of Biomedical and Pharmaceutical Sciences, Chapman University School of Pharmacy, Irvine, California (T.B.J., R.S.O.); and Department of Pharmacology, University of Nevada, Reno School of Medicine, Reno Nevada (S.R.A., R.D.H.)
| |
Collapse
|
26
|
Gherbi K, Briddon SJ, Charlton SJ. Micro-pharmacokinetics: Quantifying local drug concentration at live cell membranes. Sci Rep 2018; 8:3479. [PMID: 29472588 PMCID: PMC5823863 DOI: 10.1038/s41598-018-21100-x] [Citation(s) in RCA: 31] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2017] [Accepted: 01/24/2018] [Indexed: 12/13/2022] Open
Abstract
Fundamental equations for determining pharmacological parameters, such as the binding affinity of a ligand for its target receptor, assume a homogeneous distribution of ligand, with concentrations in the immediate vicinity of the receptor being the same as those in the bulk aqueous phase. It is, however, known that drugs are able to interact directly with the plasma membrane, potentially increasing local ligand concentrations around the receptor. We have previously reported an influence of ligand-phospholipid interactions on ligand binding kinetics at the β2-adrenoceptor, which resulted in distinct "micro-pharmacokinetic" ligand profiles. Here, we directly quantified the local concentration of BODIPY630/650-PEG8-S-propranolol (BY-propranolol), a fluorescent derivative of the classical β-blocker propranolol, at various distances above membranes of single living cells using fluorescence correlation spectroscopy. We show for the first time a significantly increased ligand concentration immediately adjacent to the cell membrane compared to the bulk aqueous phase. We further show a clear role of both the cell membrane and the β2-adrenoceptor in determining high local BY-propranolol concentrations at the cell surface. These data suggest that the true binding affinity of BY-propranolol for the β2-adrenoceptor is likely far lower than previously reported and highlights the critical importance of understanding the "micro-pharmacokinetic" profiles of ligands for membrane-associated proteins.
Collapse
Affiliation(s)
- Karolina Gherbi
- Division of Pharmacology, Physiology and Neuroscience, School of Life Sciences, Medical School, University of Nottingham, Queen's Medical Centre, Nottingham, NG7 2UH, UK.,Excellerate Bioscience Ltd, MediCity, Nottingham, NG90 6BH, UK
| | - Stephen J Briddon
- Division of Pharmacology, Physiology and Neuroscience, School of Life Sciences, Medical School, University of Nottingham, Queen's Medical Centre, Nottingham, NG7 2UH, UK.,Centre of Membrane Proteins and Receptors, Universities of Birmingham and Nottingham, The Midlands, UK
| | - Steven J Charlton
- Division of Pharmacology, Physiology and Neuroscience, School of Life Sciences, Medical School, University of Nottingham, Queen's Medical Centre, Nottingham, NG7 2UH, UK. .,Centre of Membrane Proteins and Receptors, Universities of Birmingham and Nottingham, The Midlands, UK. .,Excellerate Bioscience Ltd, MediCity, Nottingham, NG90 6BH, UK.
| |
Collapse
|
27
|
Prolonged Morphine Treatment Alters Expression and Plasma Membrane Distribution of β-Adrenergic Receptors and Some Other Components of Their Signaling System in Rat Cerebral Cortex. J Mol Neurosci 2017; 63:364-376. [PMID: 29081032 DOI: 10.1007/s12031-017-0987-9] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2017] [Accepted: 10/05/2017] [Indexed: 01/15/2023]
Abstract
β-Adrenergic signaling plays an important role in regulating diverse brain functions and alterations in this signaling have been observed in different neuropathological conditions. In this study, we investigated the effect of a 10-day treatment with high doses of morphine (10 mg/kg per day) on major components and functional state of the β-adrenergic receptor (β-AR) signaling system in the rat cerebral cortex. β-ARs were characterized by radioligand binding assays and amounts of various G protein subunits, adenylyl cyclase (AC) isoforms, G protein-coupled receptor kinases (GRKs), and β-arrestin were examined by Western blot analysis. AC activity was determined as a measure of functionality of the signaling system. We also assessed the partitioning of selected signaling proteins between the lipid raft and non-raft fractions prepared from cerebrocortical plasma membranes. Morphine treatment resulted in a significant upregulation of β-ARs, GRK3, and some AC isoforms (AC-I, -II, and -III). There was no change in quantity of G proteins and some other signaling molecules (AC-IV, AC-V/VI, GRK2, GRK5, GRK6, and β-arrestin) compared with controls. Interestingly, morphine exposure caused a partial redistribution of β-ARs, Gsα, Goα, and GRK2 between lipid rafts and bulk plasma membranes. Spatial localization of other signaling molecules within the plasma membrane was not changed. Basal as well as fluoride- and forskolin-stimulated AC activities were not significantly different in membrane preparations from control and morphine-treated animals. However, AC activity stimulated by the beta-AR agonist isoprenaline was markedly increased. This is the first study to demonstrate lipid raft association of key components of the cortical β-AR system and its sensitivity to morphine.
Collapse
|
28
|
Agarwal SR, Miyashiro K, Latt H, Ostrom RS, Harvey RD. Compartmentalized cAMP responses to prostaglandin EP 2 receptor activation in human airway smooth muscle cells. Br J Pharmacol 2017; 174:2784-2796. [PMID: 28603838 DOI: 10.1111/bph.13904] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2017] [Revised: 05/25/2017] [Accepted: 06/05/2017] [Indexed: 12/25/2022] Open
Abstract
BACKGROUND AND PURPOSE Previous studies indicate that prostaglandin EP2 receptors selectively couple to AC2 in non-lipid raft domains of airway smooth muscle (ASM) cells, where they regulate specific cAMP-dependent responses. The goal of the present study was to identify the cellular microdomains where EP2 receptors stimulate cAMP production. EXPERIMENTAL APPROACH FRET-based cAMP biosensors were targeted to different subcellular locations of primary human ASM cells. The Epac2-camps biosensor, which expresses throughout the cell, was used to measure bulk cytoplasmic responses. Epac2-MyrPalm and Epac2-CAAX were used to measure responses associated with lipid raft and non-raft regions of the plasma membrane respectively. Epac2-NLS was used to monitor responses at the nucleus. KEY RESULTS Activation of AC with forskolin or β2 -adrenoceptors with isoprenaline increased cAMP in all subcellular locations. Activation of EP2 receptors with butaprost produced cAMP responses that were most readily detected by the non-raft and nuclear sensors, but only weakly detected by the cytosolic sensor and not detected at all by the lipid raft sensor. Exposure to rolipram, a PDE4 inhibitor, unmasked the ability of EP2 receptors to increase cAMP levels associated with lipid raft domains. Overexpression of AC2 selectively increased EP2 receptor-stimulated production of cAMP in non-raft membrane domains. CONCLUSIONS AND IMPLICATIONS EP2 receptor activation of AC2 leads to cAMP production in non-raft and nuclear compartments of human ASMs, while β2 adrenoceptor signalling is broadly detected across microdomains. The activity of PDE4 appears to play a role in maintaining the integrity of compartmentalized EP2 receptor responses in these cells.
Collapse
Affiliation(s)
- Shailesh R Agarwal
- Department of Pharmacology, University of Nevada, Reno School of Medicine, Reno, NV, USA
| | - Kathryn Miyashiro
- Department of Pharmacology, University of Nevada, Reno School of Medicine, Reno, NV, USA
| | - Htun Latt
- Department of Pharmacology, University of Nevada, Reno School of Medicine, Reno, NV, USA
| | - Rennolds S Ostrom
- Department of Biomedical and Pharmaceutical Sciences, Chapman University School of Pharmacy, Irvine, CA, USA
| | - Robert D Harvey
- Department of Pharmacology, University of Nevada, Reno School of Medicine, Reno, NV, USA
| |
Collapse
|
29
|
Liu X, Wong SS, Taype CA, Kim J, Shentu TP, Espinoza CR, Finley JC, Bradley JE, Head BP, Patel HH, Mah EJ, Hagood JS. Thy-1 interaction with Fas in lipid rafts regulates fibroblast apoptosis and lung injury resolution. J Transl Med 2017; 97:256-267. [PMID: 28165468 PMCID: PMC5663248 DOI: 10.1038/labinvest.2016.145] [Citation(s) in RCA: 36] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2015] [Revised: 11/23/2016] [Accepted: 12/14/2016] [Indexed: 12/11/2022] Open
Abstract
Thy-1-negative lung fibroblasts are resistant to apoptosis. The mechanisms governing this process and its relevance to fibrotic remodeling remain poorly understood. By using either sorted or transfected lung fibroblasts, we found that Thy-1 expression is associated with downregulation of anti-apoptotic molecules Bcl-2 and Bcl-xL, as well as increased levels of cleaved caspase-9. Addition of rhFasL and staurosporine, well-known apoptosis inducers, caused significantly increased cleaved caspase-3, -8, and PARP in Thy-1-transfected cells. Furthermore, rhFasL induced Fas translocation into lipid rafts and its colocalization with Thy-1. These in vitro results indicate that Thy-1, in a manner dependent upon its glycophosphatidylinositol anchor and lipid raft localization, regulates apoptosis in lung fibroblasts via Fas-, Bcl-, and caspase-dependent pathways. In vivo, Thy-1 deficient (Thy1-/-) mice displayed persistence of myofibroblasts in the resolution phase of bleomycin-induced fibrosis, associated with accumulation of collagen and failure of lung fibrosis resolution. Apoptosis of myofibroblasts is decreased in Thy1-/- mice in the resolution phase. Collectively, these findings provide new evidence regarding the role and mechanisms of Thy-1 in initiating myofibroblast apoptosis that heralds the termination of the reparative response to bleomycin-induced lung injury. Understanding the mechanisms regulating fibroblast survival/apoptosis should lead to novel therapeutic interventions for lung fibrosis.
Collapse
Affiliation(s)
- Xiaoqiu Liu
- Respiratory Department, Second Hospital of Jilin University, Changchun, China
| | - Simon S Wong
- Division of Respiratory Medicine, Department of Pediatrics, University of California San Diego, San Diego, CA, USA
| | - Carmen A Taype
- Division of Pulmonary and Critical Care Medicine, Department of Medicine, University of California San Diego, La Jolla, CA, USA
| | - Jeeyeon Kim
- Department of Pediatrics, Stanford University, Palo Alto, CA, USA
| | - Tzu-Pin Shentu
- Division of Respiratory Medicine, Department of Pediatrics, University of California San Diego, San Diego, CA, USA
| | - Celia R Espinoza
- Division of Respiratory Medicine, Department of Pediatrics, University of California San Diego, San Diego, CA, USA
| | | | - John E Bradley
- Department of Microbiology, University of Alabama-Birmingham, Birmingham, AL, USA
| | - Brian P Head
- Department of Anesthesiology, UCSD, San Diego, CA, USA.,VA San Diego Healthcare System, San Diego, CA, USA
| | - Hemal H Patel
- Department of Anesthesiology, UCSD, San Diego, CA, USA.,VA San Diego Healthcare System, San Diego, CA, USA
| | - Emma J Mah
- Department of Chemical and Biochemical Engineering, University of California-Irvine, Irvine, CA, USA
| | - James S Hagood
- Division of Respiratory Medicine, Department of Pediatrics, University of California San Diego, San Diego, CA, USA.,Division of Respiratory Medicine, Rady Children's Hospital of San Diego, San Diego, CA, USA
| |
Collapse
|
30
|
Busija AR, Patel HH, Insel PA. Caveolins and cavins in the trafficking, maturation, and degradation of caveolae: implications for cell physiology. Am J Physiol Cell Physiol 2017; 312:C459-C477. [PMID: 28122734 DOI: 10.1152/ajpcell.00355.2016] [Citation(s) in RCA: 73] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2016] [Revised: 01/23/2017] [Accepted: 01/24/2017] [Indexed: 01/09/2023]
Abstract
Caveolins (Cavs) are ~20 kDa scaffolding proteins that assemble as oligomeric complexes in lipid raft domains to form caveolae, flask-shaped plasma membrane (PM) invaginations. Caveolae ("little caves") require lipid-lipid, protein-lipid, and protein-protein interactions that can modulate the localization, conformational stability, ligand affinity, effector specificity, and other functions of proteins that are partners of Cavs. Cavs are assembled into small oligomers in the endoplasmic reticulum (ER), transported to the Golgi for assembly with cholesterol and other oligomers, and then exported to the PM as an intact coat complex. At the PM, cavins, ~50 kDa adapter proteins, oligomerize into an outer coat complex that remodels the membrane into caveolae. The structure of caveolae protects their contents (i.e., lipids and proteins) from degradation. Cellular changes, including signal transduction effects, can destabilize caveolae and produce cavin dissociation, restructuring of Cav oligomers, ubiquitination, internalization, and degradation. In this review, we provide a perspective of the life cycle (biogenesis, degradation), composition, and physiologic roles of Cavs and caveolae and identify unanswered questions regarding the roles of Cavs and cavins in caveolae and in regulating cell physiology.1.
Collapse
Affiliation(s)
- Anna R Busija
- Department of Anesthesiology, University of California, San Diego, La Jolla, California.,Department of Pharmacology, University of California, San Diego, La Jolla, California
| | - Hemal H Patel
- Department of Anesthesiology, University of California, San Diego, La Jolla, California
| | - Paul A Insel
- Department of Medicine, University of California, San Diego, La Jolla, California; and .,Department of Pharmacology, University of California, San Diego, La Jolla, California
| |
Collapse
|
31
|
See Hoe LE, May LT, Headrick JP, Peart JN. Sarcolemmal dependence of cardiac protection and stress-resistance: roles in aged or diseased hearts. Br J Pharmacol 2016; 173:2966-91. [PMID: 27439627 DOI: 10.1111/bph.13552] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2015] [Revised: 06/27/2016] [Accepted: 06/28/2016] [Indexed: 12/25/2022] Open
Abstract
Disruption of the sarcolemmal membrane is a defining feature of oncotic death in cardiac ischaemia-reperfusion (I-R), and its molecular makeup not only fundamentally governs this process but also affects multiple determinants of both myocardial I-R injury and responsiveness to cardioprotective stimuli. Beyond the influences of membrane lipids on the cytoprotective (and death) receptors intimately embedded within this bilayer, myocardial ionic homeostasis, substrate metabolism, intercellular communication and electrical conduction are all sensitive to sarcolemmal makeup, and critical to outcomes from I-R. As will be outlined in this review, these crucial sarcolemmal dependencies may underlie not only the negative effects of age and common co-morbidities on myocardial ischaemic tolerance but also the on-going challenge of implementing efficacious cardioprotection in patients suffering accidental or surgically induced I-R. We review evidence for the involvement of sarcolemmal makeup changes in the impairment of stress-resistance and cardioprotection observed with ageing and highly prevalent co-morbid conditions including diabetes and hypercholesterolaemia. A greater understanding of membrane changes with age/disease, and the inter-dependences of ischaemic tolerance and cardioprotection on sarcolemmal makeup, can facilitate the development of strategies to preserve membrane integrity and cell viability, and advance the challenging goal of implementing efficacious 'cardioprotection' in clinically relevant patient cohorts. Linked Articles This article is part of a themed section on Molecular Pharmacology of G Protein-Coupled Receptors. To view the other articles in this section visit http://onlinelibrary.wiley.com/doi/10.1111/bph.v173.20/issuetoc.
Collapse
Affiliation(s)
- Louise E See Hoe
- Menzies Health Institute Queensland, Griffith University, Gold Coast, Australia.,Critical Care Research Group, The Prince Charles Hospital and The University of Queensland, Chermside, Queensland, Australia
| | - Lauren T May
- Monash Institute of Pharmaceutical Sciences, Monash University, Clayton, VIC, Australia
| | - John P Headrick
- Menzies Health Institute Queensland, Griffith University, Gold Coast, Australia
| | - Jason N Peart
- Menzies Health Institute Queensland, Griffith University, Gold Coast, Australia.
| |
Collapse
|
32
|
Brejchova J, Vosahlikova M, Roubalova L, Parenti M, Mauri M, Chernyavskiy O, Svoboda P. Plasma membrane cholesterol level and agonist-induced internalization of δ-opioid receptors; colocalization study with intracellular membrane markers of Rab family. J Bioenerg Biomembr 2016; 48:375-96. [DOI: 10.1007/s10863-016-9667-7] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2015] [Accepted: 06/02/2016] [Indexed: 10/21/2022]
|
33
|
Liao RS, Ma S, Miao L, Li R, Yin Y, Raj GV. Androgen receptor-mediated non-genomic regulation of prostate cancer cell proliferation. Transl Androl Urol 2016; 2:187-96. [PMID: 26816736 PMCID: PMC4708176 DOI: 10.3978/j.issn.2223-4683.2013.09.07] [Citation(s) in RCA: 40] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
Androgen receptor (AR)-mediated signaling is necessary for prostate cancer cell proliferation and an important target for therapeutic drug development. Canonically, AR signals through a genomic or transcriptional pathway, involving the translocation of androgen-bound AR to the nucleus, its binding to cognate androgen response elements on promoter, with ensuing modulation of target gene expression, leading to cell proliferation. However, prostate cancer cells can show dose-dependent proliferation responses to androgen within minutes, without the need for genomic AR signaling. This proliferation response known as the non-genomic AR signaling is mediated by cytoplasmic AR, which facilitates the activation of kinase-signaling cascades, including the Ras-Raf-1, phosphatidyl-inositol 3-kinase (PI3K)/Akt and protein kinase C (PKC), which in turn converge on mitogen-activated protein kinase (MAPK)/extracellular signal-regulated kinase (ERK) activation, leading to cell proliferation. Further, since activated ERK may also phosphorylate AR and its coactivators, the non-genomic AR signaling may enhance AR genomic activity. Non-genomic AR signaling may occur in an ERK-independent manner, via activation of mammalian target of rapamycin (mTOR) pathway, or modulation of intracellular Ca2+ concentration through plasma membrane G protein-coupled receptors (GPCRs). These data suggest that therapeutic strategies aimed at preventing AR nuclear translocation and genomic AR signaling alone may not completely abrogate AR signaling. Thus, elucidation of mechanisms that underlie non-genomic AR signaling may identify potential mechanisms of resistance to current anti-androgens and help developing novel therapies that abolish all AR signaling in prostate cancer.
Collapse
Affiliation(s)
- Ross S Liao
- Department of Urology, University of Texas Southwestern Medical Center at Dallas, Dallas, Texas 75390, USA
| | - Shihong Ma
- Department of Urology, University of Texas Southwestern Medical Center at Dallas, Dallas, Texas 75390, USA
| | - Lu Miao
- Department of Urology, University of Texas Southwestern Medical Center at Dallas, Dallas, Texas 75390, USA
| | - Rui Li
- Department of Urology, University of Texas Southwestern Medical Center at Dallas, Dallas, Texas 75390, USA
| | - Yi Yin
- Department of Urology, University of Texas Southwestern Medical Center at Dallas, Dallas, Texas 75390, USA
| | - Ganesh V Raj
- Department of Urology, University of Texas Southwestern Medical Center at Dallas, Dallas, Texas 75390, USA
| |
Collapse
|
34
|
Boularan C, Gales C. Cardiac cAMP: production, hydrolysis, modulation and detection. Front Pharmacol 2015; 6:203. [PMID: 26483685 PMCID: PMC4589651 DOI: 10.3389/fphar.2015.00203] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2015] [Accepted: 09/03/2015] [Indexed: 01/04/2023] Open
Abstract
Cyclic adenosine 3′,5′-monophosphate (cAMP) modulates a broad range of biological processes including the regulation of cardiac myocyte contractile function where it constitutes the main second messenger for β-adrenergic receptors' signaling to fulfill positive chronotropic, inotropic and lusitropic effects. A growing number of studies pinpoint the role of spatial organization of the cAMP signaling as an essential mechanism to regulate cAMP outcomes in cardiac physiology. Here, we will briefly discuss the complexity of cAMP synthesis and degradation in the cardiac context, describe the way to detect it and review the main pharmacological arsenal to modulate its availability.
Collapse
Affiliation(s)
- Cédric Boularan
- Institut des Maladies Métaboliques et Cardiovasculaires, Institut National de la Santé et de la Recherche Médicale, U1048, Université Toulouse III Paul Sabatier Toulouse, France
| | - Céline Gales
- Institut des Maladies Métaboliques et Cardiovasculaires, Institut National de la Santé et de la Recherche Médicale, U1048, Université Toulouse III Paul Sabatier Toulouse, France
| |
Collapse
|
35
|
Roubalova L, Vosahlikova M, Brejchova J, Sykora J, Rudajev V, Svoboda P. High Efficacy but Low Potency of δ-Opioid Receptor-G Protein Coupling in Brij-58-Treated, Low-Density Plasma Membrane Fragments. PLoS One 2015; 10:e0135664. [PMID: 26285205 PMCID: PMC4540457 DOI: 10.1371/journal.pone.0135664] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2014] [Accepted: 07/25/2015] [Indexed: 11/18/2022] Open
Abstract
Principal Findings HEK293 cells stably expressing PTX-insensitive δ-opioid receptor-Gi1α (C351I) fusion protein were homogenized, treated with low concentrations of non-ionic detergent Brij-58 at 0°C and fractionated by flotation in sucrose density gradient. In optimum range of detergent concentrations (0.025–0.05% w/v), Brij-58-treated, low-density membranes exhibited 2-3-fold higher efficacy of DADLE-stimulated, high-affinity [32P]GTPase and [35S]GTPγS binding than membranes of the same density prepared in the absence of detergent. The potency of agonist DADLE response was significantly decreased. At high detergent concentrations (>0.1%), the functional coupling between δ-opioid receptors and G proteins was completely diminished. The same detergent effects were measured in plasma membranes isolated from PTX-treated cells. Therefore, the effect of Brij-58 on δ-opioid receptor-G protein coupling was not restricted to the covalently bound Gi1α within δ-opioid receptor-Gi1α fusion protein, but it was also valid for PTX-sensitive G proteins of Gi/Go family endogenously expressed in HEK293 cells. Characterization of the direct effect of Brij-58 on the hydrophobic interior of isolated plasma membranes by steady-state anisotropy of diphenylhexatriene (DPH) fluorescence indicated a marked increase of membrane fluidity. The time-resolved analysis of decay of DPH fluorescence by the “wobble in cone” model of DPH motion in the membrane indicated that the exposure to the increasing concentrations of Brij-58 led to a decreased order and higher motional freedom of the dye. Summary Limited perturbation of plasma membrane integrity by low concentrations of non-ionic detergent Brij-58 results in alteration of δ-OR-G protein coupling. Maximum G protein-response to agonist stimulation (efficacy) is increased; affinity of response (potency) is decreased. The total degradation plasma membrane structure at high detergent concentrations results in diminution of functional coupling between δ-opioid receptors and G proteins.
Collapse
Affiliation(s)
- Lenka Roubalova
- Department of Biomathematics, Institute of Physiology of the Czech Academy of Sciences, Prague, Czech Republic
| | - Miroslava Vosahlikova
- Department of Biomathematics, Institute of Physiology of the Czech Academy of Sciences, Prague, Czech Republic
| | - Jana Brejchova
- Department of Biomathematics, Institute of Physiology of the Czech Academy of Sciences, Prague, Czech Republic
| | - Jan Sykora
- Department of Biophysical Chemistry, J. Heyrovsky Institute of Physical Chemistry of the Czech Academy of Sciences, Prague, Czech Republic
| | - Vladimir Rudajev
- Department of Neurochemistry, Institute of Physiology of the Czech Academy of Sciences, Prague, Czech Republic
| | - Petr Svoboda
- Department of Biomathematics, Institute of Physiology of the Czech Academy of Sciences, Prague, Czech Republic
- * E-mail:
| |
Collapse
|
36
|
Aznar N, Midde KK, Dunkel Y, Lopez-Sanchez I, Pavlova Y, Marivin A, Barbazán J, Murray F, Nitsche U, Janssen KP, Willert K, Goel A, Abal M, Garcia-Marcos M, Ghosh P. Daple is a novel non-receptor GEF required for trimeric G protein activation in Wnt signaling. eLife 2015; 4:e07091. [PMID: 26126266 PMCID: PMC4484057 DOI: 10.7554/elife.07091] [Citation(s) in RCA: 91] [Impact Index Per Article: 10.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2015] [Accepted: 06/01/2015] [Indexed: 12/17/2022] Open
Abstract
Wnt signaling is essential for tissue homeostasis and its dysregulation causes cancer. Wnt ligands trigger signaling by activating Frizzled receptors (FZDRs), which belong to the G-protein coupled receptor superfamily. However, the mechanisms of G protein activation in Wnt signaling remain controversial. In this study, we demonstrate that FZDRs activate G proteins and trigger non-canonical Wnt signaling via the Dishevelled-binding protein, Daple. Daple contains a Gα-binding and activating (GBA) motif, which activates Gαi proteins and an adjacent domain that directly binds FZDRs, thereby linking Wnt stimulation to G protein activation. This triggers non-canonical Wnt responses, that is, suppresses the β-catenin/TCF/LEF pathway and tumorigenesis, but enhances PI3K-Akt and Rac1 signals and tumor cell invasiveness. In colorectal cancers, Daple is suppressed during adenoma-to-carcinoma transformation and expressed later in metastasized tumor cells. Thus, Daple activates Gαi and enhances non-canonical Wnt signaling by FZDRs, and its dysregulation can impact both tumor initiation and progression to metastasis.
Collapse
Affiliation(s)
- Nicolas Aznar
- Department of Medicine, University of California, San Diego, San Diego, United States
| | - Krishna K Midde
- Department of Medicine, University of California, San Diego, San Diego, United States
| | - Ying Dunkel
- Department of Medicine, University of California, San Diego, San Diego, United States
| | | | - Yelena Pavlova
- Department of Medicine, University of California, San Diego, San Diego, United States
| | - Arthur Marivin
- Department of Biochemistry, Boston University School of Medicine, Boston, United States
| | - Jorge Barbazán
- Translational Medical Oncology Laboratory, Health Research Institute of Santiago, Servizo Galego de Saúde, Santiago de Compostela, Spain
| | - Fiona Murray
- Department of Medicine, University of California, San Diego, San Diego, United States
| | - Ulrich Nitsche
- Department of Surgery, Klinikum rechts der Isar, Technische Universität München, Munich, Germany
| | - Klaus-Peter Janssen
- Department of Surgery, Klinikum rechts der Isar, Technische Universität München, Munich, Germany
| | - Karl Willert
- Sanford Consortium for Regenerative Medicine, University of California, San Diego, La Jolla, California, United States
| | - Ajay Goel
- Division of Gastroenterology, Department of Internal Medicine and Charles A Sammons Cancer Center and Baylor Research Institute, Baylor University Medical Center, Dallas, Texas, United States
| | - Miguel Abal
- Translational Medical Oncology Laboratory, Health Research Institute of Santiago, Servizo Galego de Saúde, Santiago de Compostela, Spain
| | - Mikel Garcia-Marcos
- Department of Biochemistry, Boston University School of Medicine, Boston, United States
| | - Pradipta Ghosh
- Department of Medicine, University of California, San Diego, San Diego, United States
| |
Collapse
|
37
|
Potential Signal Transduction Regulation by HDL of the β2-Adrenergic Receptor Pathway. Implications in Selected Pathological Situations. Arch Med Res 2015; 46:361-71. [PMID: 26009249 DOI: 10.1016/j.arcmed.2015.05.008] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2015] [Accepted: 05/12/2015] [Indexed: 01/09/2023]
Abstract
The main atheroprotective mechanism of high-density lipoprotein (HDL) has been regarded as reverse cholesterol transport, whereby cholesterol from peripheral tissues is removed and transported to the liver for elimination. Although numerous additional atheroprotective mechanisms have been suggested, the role of HDL in modulating signal transduction of cell membrane-bound receptors has received little attention to date. This potential was recently highlighted following the identification of a polymorphism in the adenylyl cyclase 9 gene (ADCY9) that was shown to be a determining factor in the risk of cardiovascular (CV) events in patients treated with the HDL-raising compound dalcetrapib. Indeed, ADCY9 is part of the signaling pathway of the β2-adrenergic receptor (β2-AR) and both are membrane-bound proteins affected by changes in membrane-rich cholesterol plasma membrane domains (caveolae). Numerous G-protein-coupled receptors (GPCRs) and ion channels are affected by caveolae, with caveolae composition acting as a 'signalosome'. Polymorphisms in the genes encoding ADCY9 and β2-AR are associated with response to β2-agonist drugs in patients with asthma, malaria and with sickle cell disease. Crystallization of the β2-AR has found cholesterol tightly bound to transmembrane structures of the receptor. Cholesterol has also been shown to modulate the activity of this receptor. Apolipoprotein A1 (ApoA1), the major protein component of HDL, destabilizes and removes cholesterol from caveolae with high affinity through interaction with ATP-binding cassette transporter. Furthermore, β2-AR activity may be affected by ApoA1/HDL-targeted therapies. Taken together, these observations suggest a common pathway that potentially links a primary HDL function to the regulation of signal transduction.
Collapse
|
38
|
Rinaldi B, Donniacuo M, Sodano L, Gritti G, Martuscelli E, Orlandi A, Rafaniello C, Rossi F, Calzetta L, Capuano A, Matera MG. Effects of chronic treatment with the new ultra-long-acting β2 -adrenoceptor agonist indacaterol alone or in combination with the β1 -adrenoceptor blocker metoprolol on cardiac remodelling. Br J Pharmacol 2015; 172:3627-37. [PMID: 25825265 DOI: 10.1111/bph.13148] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2014] [Revised: 03/21/2015] [Accepted: 03/26/2015] [Indexed: 01/15/2023] Open
Abstract
BACKGROUND AND PURPOSE The ability of a chronic treatment with indacaterol, a new ultra-long-acting β2 -adrenoceptor agonist, to reverse cardiac remodelling and its effects in combination with metoprolol, a selective β1 -adrenoceptor antagonist, were investigated on myocardial infarction in a rat model of heart failure (HF). EXPERIMENTAL APPROACH We investigated the effects of indacaterol and metoprolol, administered alone or in combination, on myocardial histology, β-adrenoceptor-mediated pathways, markers of remodelling and haemodynamic parameters in a rat model of HF. Five groups of rats were assessed: sham-operated rats; HF rats; HF + indacaterol 0.3 mg·kg(-1) ·day(-1) ; HF + metoprolol 100 mg·kg(-1) ·day(-1) ; HF + metoprolol + indacaterol. All pharmacological treatments continued for 15 weeks. KEY RESULTS Treatment with either indacaterol or metoprolol significantly reduced the infarct size in HF rats. However, the combination of indacaterol and metoprolol reduced the infarct size even further, reduced both BP and heart rate, reversed the decrease in ejection fraction, normalized left ventricular systolic and diastolic internal diameters, normalized the decreased β1 adrenoceptor mRNA expression as well as cardiac cAMP levels and reduced cardiac GPCR kinase 2 expression, compared with the untreated HF group. CONCLUSION AND IMPLICATIONS The results of our study demonstrated an additive interaction between indacaterol and metoprolol in normalizing and reversing cardiac remodelling in our experimental model of HF. The translation of these findings to clinical practice might be of interest, as this combination of drugs could be safer and more effective in patients suffering from HF and COPD.
Collapse
Affiliation(s)
- Barbara Rinaldi
- Centre of Excellence for Cardiovascular Diseases, Second University of Naples, Naples, Italy.,Regional Centre for Pharmacovigilance and Pharmacoepidemiology, Department of Experimental Medicine, Section of Pharmacology L. Donatelli, Second University of Naples, Naples, Italy
| | - Maria Donniacuo
- Centre of Excellence for Cardiovascular Diseases, Second University of Naples, Naples, Italy
| | - Loredana Sodano
- Centre of Excellence for Cardiovascular Diseases, Second University of Naples, Naples, Italy
| | - Giulia Gritti
- Centre of Excellence for Cardiovascular Diseases, Second University of Naples, Naples, Italy
| | - Eugenio Martuscelli
- Department of Systems Medicine, University of Rome 'Tor Vergata', Rome, Italy
| | - Augusto Orlandi
- Anatomic Pathology, Department of Biomedicine and Prevention, University of Rome 'Tor Vergata', Rome, Italy
| | - Concetta Rafaniello
- Centre of Excellence for Cardiovascular Diseases, Second University of Naples, Naples, Italy.,Regional Centre for Pharmacovigilance and Pharmacoepidemiology, Department of Experimental Medicine, Section of Pharmacology L. Donatelli, Second University of Naples, Naples, Italy
| | - Francesco Rossi
- Centre of Excellence for Cardiovascular Diseases, Second University of Naples, Naples, Italy.,Regional Centre for Pharmacovigilance and Pharmacoepidemiology, Department of Experimental Medicine, Section of Pharmacology L. Donatelli, Second University of Naples, Naples, Italy
| | - Luigino Calzetta
- Department of Systems Medicine, University of Rome 'Tor Vergata', Rome, Italy
| | - Annalisa Capuano
- Centre of Excellence for Cardiovascular Diseases, Second University of Naples, Naples, Italy.,Regional Centre for Pharmacovigilance and Pharmacoepidemiology, Department of Experimental Medicine, Section of Pharmacology L. Donatelli, Second University of Naples, Naples, Italy
| | - Maria Gabriella Matera
- Centre of Excellence for Cardiovascular Diseases, Second University of Naples, Naples, Italy
| |
Collapse
|
39
|
Wypijewski KJ, Tinti M, Chen W, Lamont D, Ashford MLJ, Calaghan SC, Fuller W. Identification of caveolar resident proteins in ventricular myocytes using a quantitative proteomic approach: dynamic changes in caveolar composition following adrenoceptor activation. Mol Cell Proteomics 2015; 14:596-608. [PMID: 25561500 PMCID: PMC4349980 DOI: 10.1074/mcp.m114.038570] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
The lipid raft concept proposes that membrane environments enriched in cholesterol and sphingolipids cluster certain proteins and form platforms to integrate cell signaling. In cardiac muscle, caveolae concentrate signaling molecules and ion transporters, and play a vital role in adrenergic regulation of excitation–contraction coupling, and consequently cardiac contractility. Proteomic analysis of cardiac caveolae is hampered by the presence of contaminants that have sometimes, erroneously, been proposed to be resident in these domains. Here we present the first unbiased analysis of the proteome of cardiac caveolae, and investigate dynamic changes in their protein constituents following adrenoreceptor (AR) stimulation. Rat ventricular myocytes were treated with methyl-β-cyclodextrin (MβCD) to deplete cholesterol and disrupt caveolae. Buoyant caveolin-enriched microdomains (BCEMs) were prepared from MβCD-treated and control cell lysates using a standard discontinuous sucrose gradient. BCEMs were harvested, pelleted, and resolubilized, then alkylated, digested, and labeled with iTRAQ reagents, and proteins identified by LC-MS/MS on a LTQ Orbitrap Velos Pro. Proteins were defined as BCEM resident if they were consistently depleted from the BCEM fraction following MβCD treatment. Selective activation of α-, β1-, and β2-AR prior to preparation of BCEMs was achieved by application of agonist/antagonist pairs for 10 min in populations of field-stimulated myocytes. We typically identified 600–850 proteins per experiment, of which, 249 were defined as high-confidence BCEM residents. Functional annotation clustering indicates cardiac BCEMs are enriched in integrin signaling, guanine nucleotide binding, ion transport, and insulin signaling clusters. Proteins possessing a caveolin binding motif were poorly enriched in BCEMs, suggesting this is not the only mechanism that targets proteins to caveolae. With the notable exception of the cavin family, very few proteins show altered abundance in BCEMs following AR activation, suggesting signaling complexes are preformed in BCEMs to ensure a rapid and high fidelity response to adrenergic stimulation in cardiac muscle.
Collapse
Affiliation(s)
- Krzysztof J Wypijewski
- From the ‡Division of Cardiovascular and Diabetes Medicine, College of Medicine, Dentistry and Nursing, University of Dundee, Dundee, United Kingdom
| | - Michele Tinti
- §College of Life Sciences, University of Dundee, Dundee, United Kingdom
| | - Wenzhang Chen
- §College of Life Sciences, University of Dundee, Dundee, United Kingdom
| | - Douglas Lamont
- §College of Life Sciences, University of Dundee, Dundee, United Kingdom
| | - Michael L J Ashford
- From the ‡Division of Cardiovascular and Diabetes Medicine, College of Medicine, Dentistry and Nursing, University of Dundee, Dundee, United Kingdom
| | - Sarah C Calaghan
- ¶School of Biomedical Sciences, University of Leeds, Leeds, United Kingdom
| | - William Fuller
- From the ‡Division of Cardiovascular and Diabetes Medicine, College of Medicine, Dentistry and Nursing, University of Dundee, Dundee, United Kingdom;
| |
Collapse
|
40
|
Role of caveolin-3 in lymphocyte activation. Life Sci 2014; 121:35-9. [PMID: 25476831 DOI: 10.1016/j.lfs.2014.11.017] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2014] [Revised: 11/14/2014] [Accepted: 11/19/2014] [Indexed: 11/24/2022]
Abstract
AIMS Caveolins are structural proteins clustered in lipid-rich regions of plasma membrane involved in coordinating signal transduction in various organ systems. While caveolin-1 (Cav-1) has been shown to regulate lymphocyte activation, the role of caveolin-3 (Cav-3) in immune system signaling has not been investigated. We tested the hypothesis that Cav-3 modulates lymphocyte activation. MAIN METHODS Lymphocyte/leukocyte subpopulations from WT and Cav-3 mice were profiled with flow cytometry. Cytokine production in quiescent and activated splenocytes from WT and Cav-3 mice was assessed with ELISA. KEY FINDINGS Levels of T-cells, monocytes, and natural killer cells were not different between WT and KO mice, however KO mice had lower B-cell population-percentage. Functionally, activated lymphocytes from Cav-3 KO mice demonstrated significantly reduced expression of IL-2 compared to WT, while expression of TNFα, IL-6, and IL-10 was not different. Finally, expression of IL-17 was significantly reduced in T-helper cells from KO mice, while IFNγ was not, suggesting that Cav-3 is a determinant in the development of the Th-17 subpopulation. SIGNIFICANCE This study is the first to demonstrate that Cav-3 may be a novel participant in B-cell expression, T-cell cytokine production and activation of inflammation.
Collapse
|
41
|
Marcott PF, Mamaligas AA, Ford CP. Phasic dopamine release drives rapid activation of striatal D2-receptors. Neuron 2014; 84:164-176. [PMID: 25242218 DOI: 10.1016/j.neuron.2014.08.058] [Citation(s) in RCA: 91] [Impact Index Per Article: 9.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 08/28/2014] [Indexed: 01/04/2023]
Abstract
Striatal dopamine transmission underlies numerous goal-directed behaviors. Medium spiny neurons (MSNs) are a major target of dopamine in the striatum. However, as dopamine does not directly evoke a synaptic event in MSNs, the time course of dopamine signaling in these cells remains unclear. To examine how dopamine release activates D2-receptors on MSNs, G protein activated inwardly rectifying potassium (GIRK2; Kir 3.2) channels were virally overexpressed in the striatum, and the resulting outward currents were used as a sensor of D2-receptor activation. Electrical and optogenetic stimulation of dopamine terminals evoked robust D2-receptor inhibitory postsynaptic currents (IPSCs) in GIRK2-expressing MSNs that occurred in under a second. Evoked D2-IPSCs could be driven by repetitive stimulation and were not occluded by background dopamine tone. Together, the results indicate that D2-receptors on MSNs exhibit functional low affinity and suggest that striatal D2-receptors can encode both tonic and phasic dopamine signals.
Collapse
Affiliation(s)
- Pamela F Marcott
- Department of Physiology and Biophysics, Case Western Reserve University School of Medicine, Cleveland, OH 44106-4970, USA
| | - Aphroditi A Mamaligas
- Department of Neurosciences, Case Western Reserve University School of Medicine, Cleveland, OH 44106-4970, USA
| | - Christopher P Ford
- Department of Physiology and Biophysics, Case Western Reserve University School of Medicine, Cleveland, OH 44106-4970, USA; Department of Neurosciences, Case Western Reserve University School of Medicine, Cleveland, OH 44106-4970, USA.
| |
Collapse
|
42
|
Lin C, Ear J, Midde K, Lopez-Sanchez I, Aznar N, Garcia-Marcos M, Kufareva I, Abagyan R, Ghosh P. Structural basis for activation of trimeric Gi proteins by multiple growth factor receptors via GIV/Girdin. Mol Biol Cell 2014; 25:3654-71. [PMID: 25187647 PMCID: PMC4230624 DOI: 10.1091/mbc.e14-05-0978] [Citation(s) in RCA: 50] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023] Open
Abstract
GIV, a guanidine exchange factor for trimeric Gi, contains a unique domain that functions like a SH2 domain. GIV's SH2-like domain binds autophosphorylated RTKs. Binding of GIV's SH2 to RTKs enables the receptors to activate trimeric Gi. Inhibition of GIV:RTK interaction abolishes GIV-dependent Akt enhancement downstream of RTKs. A long-standing issue in the field of signal transduction is to understand the cross-talk between receptor tyrosine kinases (RTKs) and heterotrimeric G proteins, two major and distinct signaling hubs that control eukaryotic cell behavior. Although stimulation of many RTKs leads to activation of trimeric G proteins, the molecular mechanisms behind this phenomenon remain elusive. We discovered a unifying mechanism that allows GIV/Girdin, a bona fide metastasis-related protein and a guanine-nucleotide exchange factor (GEF) for Gαi, to serve as a direct platform for multiple RTKs to activate Gαi proteins. Using a combination of homology modeling, protein–protein interaction, and kinase assays, we demonstrate that a stretch of ∼110 amino acids within GIV C-terminus displays structural plasticity that allows folding into a SH2-like domain in the presence of phosphotyrosine ligands. Using protein–protein interaction assays, we demonstrated that both SH2 and GEF domains of GIV are required for the formation of a ligand-activated ternary complex between GIV, Gαi, and growth factor receptors and for activation of Gαi after growth factor stimulation. Expression of a SH2-deficient GIV mutant (Arg 1745→Leu) that cannot bind RTKs impaired all previously demonstrated functions of GIV—Akt enhancement, actin remodeling, and cell migration. The mechanistic and structural insights gained here shed light on the long-standing questions surrounding RTK/G protein cross-talk, set a novel paradigm, and characterize a unique pharmacological target for uncoupling GIV-dependent signaling downstream of multiple oncogenic RTKs.
Collapse
Affiliation(s)
- Changsheng Lin
- Department of Medicine, University of California, San Diego, School of Medicine, CA 92093
| | - Jason Ear
- Department of Medicine, University of California, San Diego, School of Medicine, CA 92093
| | - Krishna Midde
- Department of Medicine, University of California, San Diego, School of Medicine, CA 92093
| | | | - Nicolas Aznar
- Department of Medicine, University of California, San Diego, School of Medicine, CA 92093
| | - Mikel Garcia-Marcos
- Department of Cellular and Molecular Medicine, University of California, San Diego, School of Medicine, CA 92093
| | - Irina Kufareva
- Skaggs School of Pharmacy and Pharmaceutical Sciences, University of California, San Diego, La Jolla, CA 92093
| | - Ruben Abagyan
- Skaggs School of Pharmacy and Pharmaceutical Sciences, University of California, San Diego, La Jolla, CA 92093
| | - Pradipta Ghosh
- Department of Medicine, University of California, San Diego, School of Medicine, CA 92093
| |
Collapse
|
43
|
Tse KH, Chow KBS, Leung WK, Wong YH, Wise H. Primary sensory neurons regulate Toll-like receptor-4-dependent activity of glial cells in dorsal root ganglia. Neuroscience 2014; 279:10-22. [PMID: 25171787 DOI: 10.1016/j.neuroscience.2014.08.033] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2014] [Revised: 07/10/2014] [Accepted: 08/11/2014] [Indexed: 12/21/2022]
Abstract
Toll-like receptor-4 (TLR4) has been identified in primary sensory neurons, both in vivo and in vitro, but is reportedly absent from satellite glial cells (SGCs). Herein we reveal that, in rat dorsal root ganglia (DRG), SGCs do express TLR4 but this expression is inhibited by direct contact with neurons. Thus, TLR4 mRNA and protein is strongly up-regulated in isolated DRG glial cells in the absence of neurons. Lipopolysaccharide (LPS) increased cyclooxygenase-2 (COX-2) and tumor necrosis factor-α (TNFα) mRNA expression with greater efficacy in DRG glial cell cultures than in mixed DRG cell cultures containing TLR4-positive neurons. Using an insert co-culture system, we have shown that neuronal inhibition of glial cell TLR4 is likely to be dependent on cell-cell contact rather than diffusible factors from neurons. LPS stimulated prostaglandin E2 (PGE2) production from DRG glial cells in a TLR4- and COX-2-dependent manner. In addition, exogenous PGE2 potentiated LPS-stimulated COX-2 mRNA while inhibiting TNFα mRNA expression by DRG cells, suggestive of a complex regulatory system to control inflammation within the DRG. In addition to LPS, conditioned medium from heat-shocked DRG neurons also increased COX-2 mRNA expression in DRG glial cells in a partially TLR4-dependent manner. We therefore hypothesize that neuronal suppression of glial TLR4 activity is a protective mechanism to prevent uncontrolled inflammation within the DRG. Under conditions where DRG neuronal viability is compromised, DRG glial cells become responsive to PAMPs (pathogen-associated molecular patterns) and DAMPs (danger-associated molecular patterns) and generate a range of classical inflammatory responses.
Collapse
Affiliation(s)
- K-H Tse
- School of Biomedical Sciences, The Chinese University of Hong Kong, Hong Kong Special Administrative Region
| | - K B S Chow
- School of Biomedical Sciences, The Chinese University of Hong Kong, Hong Kong Special Administrative Region
| | - W K Leung
- Faculty of Dentistry, The University of Hong Kong, Hong Kong Special Administrative Region
| | - Y H Wong
- Division of Life Science, The Hong Kong University of Science and Technology, Hong Kong Special Administrative Region
| | - H Wise
- School of Biomedical Sciences, The Chinese University of Hong Kong, Hong Kong Special Administrative Region.
| |
Collapse
|
44
|
Saucerman JJ, Greenwald EC, Polanowska-Grabowska R. Mechanisms of cyclic AMP compartmentation revealed by computational models. ACTA ACUST UNITED AC 2014; 143:39-48. [PMID: 24378906 PMCID: PMC3874575 DOI: 10.1085/jgp.201311044] [Citation(s) in RCA: 52] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Affiliation(s)
- Jeffrey J Saucerman
- Department of Biomedical Engineering and Robert M. Berne Cardiovascular Research Center, University of Virginia, Charlottesville, VA 22908
| | | | | |
Collapse
|
45
|
See Hoe LE, Schilling JM, Tarbit E, Kiessling CJ, Busija AR, Niesman IR, Du Toit E, Ashton KJ, Roth DM, Headrick JP, Patel HH, Peart JN. Sarcolemmal cholesterol and caveolin-3 dependence of cardiac function, ischemic tolerance, and opioidergic cardioprotection. Am J Physiol Heart Circ Physiol 2014; 307:H895-903. [PMID: 25063791 DOI: 10.1152/ajpheart.00081.2014] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Cholesterol-rich caveolar microdomains and associated caveolins influence sarcolemmal ion channel and receptor function and protective stress signaling. However, the importance of membrane cholesterol content to cardiovascular function and myocardial responses to ischemia-reperfusion (I/R) and cardioprotective stimuli are unclear. We assessed the effects of graded cholesterol depletion with methyl-β-cyclodextrin (MβCD) and lifelong knockout (KO) or overexpression (OE) of caveolin-3 (Cav-3) on cardiac function, I/R tolerance, and opioid receptor (OR)-mediated protection. Langendorff-perfused hearts from young male C57Bl/6 mice were untreated or treated with 0.02-1.0 mM MβCD for 25 min to deplete membrane cholesterol and disrupt caveolae. Hearts were subjected to 25-min ischemia/45-min reperfusion, and the cardioprotective effects of morphine applied either acutely or chronically [sustained ligand-activated preconditioning (SLP)] were assessed. MβCD concentration dependently reduced normoxic contractile function and postischemic outcomes in association with graded (10-30%) reductions in sarcolemmal cholesterol. Cardioprotection with acute morphine was abolished with ≥20 μM MβCD, whereas SLP was more robust and only inhibited with ≥200 μM MβCD. Deletion of Cav-3 also reduced, whereas Cav-3 OE improved, myocardial I/R tolerance. Protection via SLP remained equally effective in Cav-3 KO mice and was additive with innate protection arising with Cav-3 OE. These data reveal the membrane cholesterol dependence of normoxic myocardial and coronary function, I/R tolerance, and OR-mediated cardioprotection in murine hearts (all declining with cholesterol depletion). In contrast, baseline function appears insensitive to Cav-3, whereas cardiac I/R tolerance parallels Cav-3 expression. Novel SLP appears unique, being less sensitive to cholesterol depletion than acute OR protection and arising independently of Cav-3 expression.
Collapse
Affiliation(s)
- Louise E See Hoe
- Heart Foundation Research Centre, Griffith Health Institute, Griffith University, Southport, Queensland, Australia
| | - Jan M Schilling
- Veterans Affairs San Diego Healthcare System, San Diego, California
| | - Emiri Tarbit
- Heart Foundation Research Centre, Griffith Health Institute, Griffith University, Southport, Queensland, Australia
| | - Can J Kiessling
- Faculty of Health Sciences and Medicine, Bond University, Robina, Queensland, Australia; and
| | - Anna R Busija
- Veterans Affairs San Diego Healthcare System, San Diego, California
| | - Ingrid R Niesman
- Veterans Affairs San Diego Healthcare System, San Diego, California
| | - Eugene Du Toit
- Heart Foundation Research Centre, Griffith Health Institute, Griffith University, Southport, Queensland, Australia
| | - Kevin J Ashton
- Faculty of Health Sciences and Medicine, Bond University, Robina, Queensland, Australia; and
| | - David M Roth
- Veterans Affairs San Diego Healthcare System, San Diego, California; Department of Anesthesiology, University of California, San Diego, California
| | - John P Headrick
- Heart Foundation Research Centre, Griffith Health Institute, Griffith University, Southport, Queensland, Australia
| | - Hemal H Patel
- Veterans Affairs San Diego Healthcare System, San Diego, California; Department of Anesthesiology, University of California, San Diego, California
| | - Jason N Peart
- Heart Foundation Research Centre, Griffith Health Institute, Griffith University, Southport, Queensland, Australia;
| |
Collapse
|
46
|
GIV/Girdin is a central hub for profibrogenic signalling networks during liver fibrosis. Nat Commun 2014; 5:4451. [PMID: 25043713 PMCID: PMC4107319 DOI: 10.1038/ncomms5451] [Citation(s) in RCA: 79] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2014] [Accepted: 06/18/2014] [Indexed: 01/18/2023] Open
Abstract
Progressive liver fibrosis is characterized by the deposition of collagen by activated hepatic stellate cells (HSCs). Activation of HSCs is a multiple receptor-driven process in which profibrotic signals are enhanced, and anti-fibrotic pathways are suppressed. Here we report the discovery of a novel signaling platform comprised of G protein subunit, Gαi and GIV, its guanine exchange factor (GEF), which serves as a central hub within the fibrogenic signalling network initiated by diverse classes of receptors. GIV is expressed in the liver after fibrogenic injury and is required for HSC activation. Once expressed, GIV enhances the profibrotic (PI3K-Akt-FoxO1 and TGFβ-SMAD) and inhibits the anti-fibrotic (cAMP-PKA-pCREB) pathways to skew the signalling network in favor of fibrosis, all via activation of Gαi. We also provide evidence that GIV may serve as a biomarker for progression of fibrosis after liver injury and a therapeutic target for arresting and/or reversing HSC activation during liver fibrosis.
Collapse
|
47
|
Yu P, Sun M, Villar VAM, Zhang Y, Weinman EJ, Felder RA, Jose PA. Differential dopamine receptor subtype regulation of adenylyl cyclases in lipid rafts in human embryonic kidney and renal proximal tubule cells. Cell Signal 2014; 26:2521-9. [PMID: 25049074 DOI: 10.1016/j.cellsig.2014.07.003] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2014] [Accepted: 07/09/2014] [Indexed: 01/11/2023]
Abstract
Dopamine D1-like receptors (D1R and D5R) stimulate adenylyl cyclase (AC) activity, whereas the D2-like receptors (D2, D3 and D4) inhibit AC activity. D1R, but not the D5R, has been reported to regulate AC activity in lipid rafts (LRs). We tested the hypothesis that D1R and D5R differentially regulate AC activity in LRs using human embryonic kidney (HEK) 293 cells heterologously expressing human D1 or D5 receptor (HEK-hD1R or HEK-hD5R) and human renal proximal tubule (hRPT) cells that endogenously express D1R and D5R. Of the AC isoforms expressed in HEK and hRPT cells (AC3, AC5, AC6, AC7, and AC9), AC5/6 was distributed to a greater extent in LRs than non-LRs in HEK-hD1R (84.5±2.3% of total), HEK-hD5R (68.9±3.1% of total), and hRPT cells (66.6 ± 2.2% of total) (P<0.05, n=4/group). In HEK-hD1R cells, the D1-like receptor agonist fenoldopam (1 μM/15 min) increased AC5/6 protein (+17.2 ± 3.9% of control) in LRs but decreased it in non-LRs (-47.3±5.3% of control) (P<0.05, vs. control, n=4/group). By contrast, in HEK-hD5R cells, fenoldopam increased AC5/6 protein in non-LRs (+67.1 ± 5.3% of control, P<0.006, vs. control, n=4) but had no effect in LRs. In hRPT cells, fenoldopam increased AC5/6 in LRs but had little effect in non-LRs. Disruption of LRs with methyl-β-cyclodextrin decreased basal AC activity in HEK-D1R (-94.5 ± 2.0% of control) and HEK-D5R cells (-87.1 ± 4.6% of control) but increased it in hRPT cells (6.8±0.5-fold). AC6 activity was stimulated to a greater extent by D1R than D5R, in agreement with the greater colocalization of AC5/6 with D1R than D5R in LRs. We conclude that LRs are essential not only for the proper membrane distribution and maintenance of AC5/6 activity but also for the regulation of D1R- and D5R-mediated AC signaling.
Collapse
Affiliation(s)
- Peiying Yu
- Division of Nephrology, Department of Medicine, University of Maryland School of Medicine, Baltimore, MD 21201, United States
| | - Min Sun
- Department of Biological Sciences, School of Life Science, Anhui University, Anhui, China
| | - Van Anthony M Villar
- Division of Nephrology, Department of Medicine, University of Maryland School of Medicine, Baltimore, MD 21201, United States
| | - Yanrong Zhang
- Division of Nephrology, Department of Medicine, University of Maryland School of Medicine, Baltimore, MD 21201, United States
| | - Edward J Weinman
- Division of Nephrology, Department of Medicine, University of Maryland School of Medicine, Baltimore, MD 21201, United States
| | - Robin A Felder
- Department of Pathology, University of Virginia Health Sciences Center, Charlottesville, VA 22903, United States
| | - Pedro A Jose
- Division of Nephrology, Department of Medicine, University of Maryland School of Medicine, Baltimore, MD 21201, United States; Department of Physiology, University of Maryland School of Medicine, Baltimore, MD 21201, United States
| |
Collapse
|
48
|
Agarwal SR, Yang PC, Rice M, Singer CA, Nikolaev VO, Lohse MJ, Clancy CE, Harvey RD. Role of membrane microdomains in compartmentation of cAMP signaling. PLoS One 2014; 9:e95835. [PMID: 24752595 PMCID: PMC3994114 DOI: 10.1371/journal.pone.0095835] [Citation(s) in RCA: 63] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2013] [Accepted: 03/31/2014] [Indexed: 12/03/2022] Open
Abstract
Spatially restricting cAMP production to discrete subcellular locations permits selective regulation of specific functional responses. But exactly where and how cAMP signaling is confined is not fully understood. Different receptors and adenylyl cyclase isoforms responsible for cAMP production are not uniformly distributed between lipid raft and non-lipid raft domains of the plasma membrane. We sought to determine the role that these membrane domains play in organizing cAMP responses in HEK293 cells. The freely diffusible FRET-based biosensor Epac2-camps was used to measure global cAMP responses, while versions of the probe targeted to lipid raft (Epac2-MyrPalm) and non-raft (Epac2-CAAX) domains were used to monitor local cAMP production near the plasma membrane. Disruption of lipid rafts by cholesterol depletion selectively altered cAMP responses produced by raft-associated receptors. The results indicate that receptors associated with lipid raft as well as non-lipid raft domains can contribute to global cAMP responses. In addition, basal cAMP activity was found to be significantly higher in non-raft domains. This was supported by the fact that pharmacologic inhibition of adenylyl cyclase activity reduced basal cAMP activity detected by Epac2-CAAX but not Epac2-MyrPalm or Epac2-camps. Responses detected by Epac2-CAAX were also more sensitive to direct stimulation of adenylyl cyclase activity, but less sensitive to inhibition of phosphodiesterase activity. Quantitative modeling was used to demonstrate that differences in adenylyl cyclase and phosphodiesterase activities are necessary but not sufficient to explain compartmentation of cAMP associated with different microdomains of the plasma membrane.
Collapse
Affiliation(s)
- Shailesh R. Agarwal
- Department of Pharmacology, University of Nevada School of Medicine, Reno, Nevada, United States of America
| | - Pei-Chi Yang
- Department of Pharmacology, University of California Davis, Davis, California, United States of America
| | - Monica Rice
- Department of Pharmacology, University of Nevada School of Medicine, Reno, Nevada, United States of America
| | - Cherie A. Singer
- Department of Pharmacology, University of Nevada School of Medicine, Reno, Nevada, United States of America
| | - Viacheslav O. Nikolaev
- European Heart Research Institute Gottingen, University of Göttingen, Göttingen, Germany
| | - Martin J. Lohse
- Department of Pharmacology, University of Würzburg, Würzburg, Germany
| | - Colleen E. Clancy
- Department of Pharmacology, University of California Davis, Davis, California, United States of America
| | - Robert D. Harvey
- Department of Pharmacology, University of Nevada School of Medicine, Reno, Nevada, United States of America
- * E-mail:
| |
Collapse
|
49
|
Kittikulsuth W, Stuart D, Kohan DE. Adenylyl cyclase 4 does not regulate collecting duct water and sodium handling. Physiol Rep 2014; 2:e00277. [PMID: 24760529 PMCID: PMC4002255 DOI: 10.1002/phy2.277] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023] Open
Abstract
Adenylyl cyclase (AC)‐stimulated cAMP is a key mediator of collecting duct (CD) Na and water transport. AC isoforms 3, 4, and 6 are expressed in the CD. Our group demonstrated that AC6, but not AC3, is involved in regulating CD Na and water transport. However, the role of AC4 in such regulation remains unknown. Therefore, we generated mice with loxP‐flanked critical exons in the Adcy4 gene and bred with mice expressing the aquaporin‐2/Cre recombinase transgene to yield CD principal cell‐specific knockout of AC4 (CD AC4 KO). Isolated inner medullary CD showed 100% genomic target gene recombination in CD AC4 KO mice, while microdissected cortical CD and renal papillary AC4 mRNA was significantly reduced in CD AC4 KO mice. CD AC4 KO had no effect on vasopressin (AVP)‐stimulated cAMP generation in the inner medulla. Water intake, urine volume, and urine osmolality were similar between CD AC4 KO and control mice during normal or restricted water intake. Sodium intake, urinary Na excretion, and blood pressure on a normal‐, high‐, or low‐Na diet were not affected by CD AC4 KO. Moreover, there were no differences in plasma AVP or plasma renin concentration between CD AC4 KO and control mice. In summary, these data suggest that CD AC4 does not play a role in the physiologic regulation of CD Na and water handling. Principal cells in the collecting duct express adenylyl cyclase 4 (AC4), however, the role of AC4 in the regulation of collecting duct function is unknown. We made mice with collecting duct principal cell‐specific deletion of AC4 and found that these mice have no alterations in arterial pressure or urinary sodium, potassium, or water excretion under varying physiological conditions.
Collapse
Affiliation(s)
- Wararat Kittikulsuth
- Division of Nephrology, University of Utah Health Sciences Center, Salt Lake City Veterans Affairs Medical Center, Salt Lake City, Utah
| | | | | |
Collapse
|
50
|
Geranylgeranylacetone protects the heart via caveolae and caveolin-3. Life Sci 2014; 101:43-8. [PMID: 24582814 DOI: 10.1016/j.lfs.2014.02.019] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2013] [Revised: 01/11/2014] [Accepted: 02/12/2014] [Indexed: 12/11/2022]
Abstract
AIMS Geranylgeranylacetone (GGA) is commonly utilized to protect the gastric mucosa in peptic ulcer disease. Recently GGA has been shown to protect the myocardium from ischemia/reperfusion by activating heat shock proteins. However, the exact mechanism as to how GGA activates these protective proteins is unknown. Caveolae and caveolin-3 (Cav-3) have been implicated in ischemia, anesthetic, and opioid induced cardiac protection. Given the lipophilic nature of GGA it is our hypothesis that GGA induced cardiac protection requires caveolae and Cav-3. MAIN METHODS We used an in vivo mouse model of ischemia-reperfusion injury and performed biochemical assays in excised hearts. KEY FINDINGS GGA treated control mice revealed increased caveolae formation and caveolin-3 in buoyant fractions, mediating heat shock protein 70 activation. Furthermore, control mice treated with GGA were protected against ischemia/reperfusion injury whereas Cav-3 knockout (Cav-3 KO) mice were not. Troponin levels confirmed myocardial damage. Finally, Cav-3 KO mice treated with GGA were not protected against mitochondrial swelling whereas control mice had significant protection. SIGNIFICANCE This study showed that caveolae and caveolin-3 are essential in facilitating GGA induced cardiac protection by optimizing spatial and temporal signaling to the mitochondria.
Collapse
|