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Villalobos-Escobedo FS, Jijón-Lorenzo R, Avalos-Fuentes JA, Paz-Bermúdez F, Recillas-Morales S, Rojas IC, Leyva-Gómez G, Cortés H, Florán B. Dopamine D3 receptor modulates D2 receptor effects on cAMP and GABA release at striatopallidal terminals-Modulation by the Ca 2+-Calmodulin-CaMKII system. Eur J Neurosci 2024; 59:1441-1459. [PMID: 38151481 DOI: 10.1111/ejn.16237] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2023] [Revised: 11/15/2023] [Accepted: 11/21/2023] [Indexed: 12/29/2023]
Abstract
Dopamine D2 receptor (D2R) is expressed in striatopallidal neurons and decreases forskolin-stimulated cyclic adenine monophosphate (cAMP) accumulation and gamma-aminobutyric acid (GABA) release. Dopamine D3 receptor (D3R) mRNA is expressed in a population of striatal D2R-expressing neurons. Also, D3R protein and binding have been reported in the neuropil of globus pallidus. We explore whether D2R and D3R colocalize in striatopallidal terminals and whether D3R modulates the D2R effect on forskolin-stimulated [3H]cAMP accumulation in pallidal synaptosomes and high K+ stimulated-[3H]GABA release in pallidal slices. Previous reports in heterologous systems indicate that calmodulin (CaM) and CaMKII modulate D2R and D3R functions; thus, we study whether this system regulates its functional interaction. D2R immunoprecipitates with CaM, and pretreatment with ophiobolin A or depolarization of synaptosomes with 15 mM of K+ decreases it. Both treatments increase the D2R inhibition of forskolin-stimulated [3H]cAMP accumulation when activated with quinpirole, indicating a negative modulation of CaM on D2R function. Quinpirole also activates D3R, potentiating D2R inhibition of cAMP accumulation in the ophiobolin A-treated synaptosomes. D2R and D3R immunoprecipitate in pallidal synaptosomes and decrease after the kainic acid striatal lesion, indicating the striatal origin of the presynaptic receptors. CaM-kinase II alfa (CaMKIIα) immunoprecipitates with D3R and increases after high K+ depolarization. In the presence of KN62, a CaMKIIα blocker, D3R potentiates D2R effects on cAMP accumulation in depolarized synaptosomes and GABA release in pallidal slices, indicating D3R function regulation by CaMKIIα. Our data indicate that D3R potentiates the D2R effect on cAMP accumulation and GABA release at pallidal terminals, an interaction regulated by the CaM-CaMKIIα system.
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Affiliation(s)
- Flor Selene Villalobos-Escobedo
- Departamento de Fisiología, Biofísica y Neurociencias, Centro de Investigación y de Estudios Avanzados del Instituto Politécnico Nacional, Mexico City, Mexico
| | - Rafael Jijón-Lorenzo
- Departamento de Fisiología, Biofísica y Neurociencias, Centro de Investigación y de Estudios Avanzados del Instituto Politécnico Nacional, Mexico City, Mexico
| | - José Arturo Avalos-Fuentes
- Departamento de Fisiología, Biofísica y Neurociencias, Centro de Investigación y de Estudios Avanzados del Instituto Politécnico Nacional, Mexico City, Mexico
| | - Francisco Paz-Bermúdez
- Departamento de Fisiología, Biofísica y Neurociencias, Centro de Investigación y de Estudios Avanzados del Instituto Politécnico Nacional, Mexico City, Mexico
| | | | - Israel Conde Rojas
- Neurobiology of Eating, FES-Iztacala, Universidad Nacional Autónoma de Mexico, Mexico City, Mexico
| | - Gerardo Leyva-Gómez
- Departamento de Farmacia, Facultad de Química, Universidad Nacional Autónoma de Mexico, Mexico City, Mexico
| | - Hernán Cortés
- Laboratorio de Medicina Genómica, Departamento de Genómica, Instituto Nacional de Rehabilitación Luis Guillermo Ibarra Ibarra, Mexico City, Mexico
| | - Benjamín Florán
- Departamento de Fisiología, Biofísica y Neurociencias, Centro de Investigación y de Estudios Avanzados del Instituto Politécnico Nacional, Mexico City, Mexico
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Cuanalo-Contreras K, Schulz J, Mukherjee A, Park KW, Armijo E, Soto C. Extensive accumulation of misfolded protein aggregates during natural aging and senescence. Front Aging Neurosci 2023; 14:1090109. [PMID: 36778589 PMCID: PMC9909609 DOI: 10.3389/fnagi.2022.1090109] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2022] [Accepted: 12/22/2022] [Indexed: 01/27/2023] Open
Abstract
Accumulation of misfolded protein aggregates is a hallmark event in many age-related protein misfolding disorders, including some of the most prevalent and insidious neurodegenerative diseases. Misfolded protein aggregates produce progressive cell damage, organ dysfunction, and clinical changes, which are common also in natural aging. Thus, we hypothesized that aging is associated to the widespread and progressive misfolding and aggregation of many proteins in various tissues. In this study, we analyzed whether proteins misfold, aggregate, and accumulate during normal aging in three different biological systems, namely senescent cells, Caenorhabditis elegans, and mouse tissues collected at different times from youth to old age. Our results show a significant accumulation of misfolded protein aggregates in aged samples as compared to young materials. Indeed, aged samples have between 1.3 and 2.5-fold (depending on the biological system) higher amount of insoluble proteins than young samples. These insoluble proteins exhibit the typical characteristics of disease-associated aggregates, including insolubility in detergents, protease resistance, and staining with amyloid-binding dye as well as accumulation in aggresomes. We identified the main proteins accumulating in the aging brain using proteomic studies. These results show that the aged brain contain large amounts of misfolded and likely non-functional species of many proteins, whose soluble versions participate in cellular pathways that play fundamental roles in preserving basic functions, such as protein quality control, synapsis, and metabolism. Our findings reveal a putative role for protein misfolding and aggregation in aging.
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Affiliation(s)
- Karina Cuanalo-Contreras
- Mitchell Center for Alzheimer’s Disease and Related Brain Disorders, Department of Neurology, McGovern Medical School, University of Texas Health Science Center at Houston, Houston, TX, United States
| | - Jonathan Schulz
- Mitchell Center for Alzheimer’s Disease and Related Brain Disorders, Department of Neurology, McGovern Medical School, University of Texas Health Science Center at Houston, Houston, TX, United States
| | - Abhisek Mukherjee
- Mitchell Center for Alzheimer’s Disease and Related Brain Disorders, Department of Neurology, McGovern Medical School, University of Texas Health Science Center at Houston, Houston, TX, United States
| | - Kyung-Won Park
- Mitchell Center for Alzheimer’s Disease and Related Brain Disorders, Department of Neurology, McGovern Medical School, University of Texas Health Science Center at Houston, Houston, TX, United States
| | - Enrique Armijo
- Mitchell Center for Alzheimer’s Disease and Related Brain Disorders, Department of Neurology, McGovern Medical School, University of Texas Health Science Center at Houston, Houston, TX, United States,Facultad de Medicina, Universidad de los Andes, Santiago, Chile
| | - Claudio Soto
- Mitchell Center for Alzheimer’s Disease and Related Brain Disorders, Department of Neurology, McGovern Medical School, University of Texas Health Science Center at Houston, Houston, TX, United States,Facultad de Medicina, Universidad de los Andes, Santiago, Chile,*Correspondence: Claudio Soto,
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Rodriguez-Contreras D, Condon AF, Buck DC, Asad N, Dore TM, Verbeek DS, Tijssen MAJ, Shinde U, Williams JT, Neve KA. Signaling-Biased and Constitutively Active Dopamine D2 Receptor Variant. ACS Chem Neurosci 2021; 12:1873-1884. [PMID: 33974399 DOI: 10.1021/acschemneuro.0c00712] [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] [Indexed: 12/16/2022] Open
Abstract
A dopamine D2 receptor mutation was recently identified in a family with a novel hyperkinetic movement disorder. Compared to the wild type D2 receptor, the novel allelic variant D2-I212F activates a Gαi1β1γ2 heterotrimer with higher potency and modestly enhanced basal activity in human embryonic kidney (HEK) 293 cells and has decreased capacity to recruit arrestin3. We now report that omitting overexpressed G protein-coupled receptor kinase-2 (GRK2) decreased the potency and efficacy of quinpirole for arrestin recruitment. The relative efficacy of quinpirole for arrestin recruitment to D2-I212F compared to D2-WT was considerably lower without overexpressed GRK2 than with added GRK2. D2-I212F exhibited higher basal activation of GαoA than Gαi1 but little or no increase in the potency of quinpirole relative to D2-WT. Other signs of D2-I212F constitutive activity for G protein-mediated signaling, in addition to basal activation of Gαi/o, were enhanced basal inhibition of forskolin-stimulated cyclic AMP accumulation that was reversed by the inverse agonists sulpiride and spiperone and a ∼4-fold increase in the apparent affinity of D2-I212F for quinpirole, determined from competition binding assays. In mouse midbrain slices, inhibition of tonic current by the inverse agonist sulpiride in dopamine neurons expressing D2-I212F was consistent with our hypothesis of enhanced constitutive activity and sensitivity to dopamine relative to D2-WT. Molecular dynamics simulations with D2 receptor models suggested that an ionic lock between the cytoplasmic ends of the third and sixth α-helices that constrains many G protein-coupled receptors in an inactive conformation spontaneously breaks in D2-I212F. Overall, these results confirm that D2-I212F is a constitutively active and signaling-biased D2 receptor mutant and also suggest that the effect of the likely pathogenic variant in a given brain region will depend on the nature of G protein and GRK expression.
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Affiliation(s)
- Dayana Rodriguez-Contreras
- Research Service, VA Portland Health Care System, and Department of Behavioral Neuroscience, Oregon Health & Science University, Portland, Oregon 97239, United States
| | - Alec F. Condon
- Vollum Institute, Oregon Health & Science University, Portland, Oregon 97239, United States
| | - David C. Buck
- Research Service, VA Portland Health Care System, Portland, Oregon 97239, United States
| | - Naeem Asad
- New York University Abu Dhabi, Saadiyat Island, PO Box 129188, Abu Dhabi, United Arab Emirates
| | - Timothy M. Dore
- New York University Abu Dhabi, Saadiyat Island, PO Box 129188, Abu Dhabi, United Arab Emirates
| | - Dineke S. Verbeek
- Expertise Center Movement Disorders and Department of Genetics, University of Groningen, 9700 AB Groningen, The Netherlands
| | - Marina A. J. Tijssen
- Expertise Center Movement Disorders and Department of Neurology, University of Groningen, 9700 AB Groningen, The Netherlands
| | - Ujwal Shinde
- Department of Chemical Physiology & Biochemistry, Oregon Health & Science University, Portland, Oregon 97239, United States
| | - John T. Williams
- Vollum Institute, Oregon Health & Science University, Portland, Oregon 97239, United States
| | - Kim A. Neve
- Research Service, VA Portland Health Care System, and Department of Behavioral Neuroscience, Oregon Health & Science University, Portland, Oregon 97239, United States
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Lee HJ, Rodriguez-Contreras D, Neve KA. Commentary on "Novel Interaction of the Dopamine D2 Receptor and the Ca 2+ Binding Protein S100B: Role in D2 Receptor Function". Mol Pharmacol 2021; 100:61-64. [PMID: 34045267 DOI: 10.1124/molpharm.121.000284] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2021] [Accepted: 04/30/2021] [Indexed: 11/22/2022] Open
Abstract
We previously proposed that the dopamine D2 receptor-interacting protein S100B binds to a putative S100B-binding motif at residues R233-L240 toward the N terminus of the third intracellular loop. We used in vitro pull-down assays with FLAG-tagged fragments of the rat dopamine D2 receptor third intracellular loop (D2-IC3) and in vitro-synthesized S100B to evaluate this hypothesis. Our results indicate that the putative S100B-binding motif is neither necessary nor sufficient for strong binding of S100B to D2-IC3. Instead, two residues at the junction of the fifth membrane-spanning domain and the cytoplasmic extension of that α-helical domain, K211-I212, are required for robust, calcium-sensitive binding of S100B. This is also the approximate location of previously identified determinants for the binding of arrestin and calmodulin. A D2 receptor mutation converting I212 to phenylalanine has been described in patients with a hyperkinetic movement disorder. SIGNIFICANCE STATEMENT: S100B is a small calcium-binding protein that modulates signaling by the dopamine D2 receptor. New data suggest that the previous hypothesis about the involvement of an S100B-binding motif is incorrect, and that an important determinant of S100B binding includes a residue that is mutated in patients with a hyperkinetic movement disorder.
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Affiliation(s)
- Hun-Joo Lee
- Research Service, VA Portland Health Care System, Portland, Oregon, and Department of Behavioral Neuroscience, Oregon Health & Science University, Portland, Oregon
| | - Dayana Rodriguez-Contreras
- Research Service, VA Portland Health Care System, Portland, Oregon, and Department of Behavioral Neuroscience, Oregon Health & Science University, Portland, Oregon
| | - Kim A Neve
- Research Service, VA Portland Health Care System, Portland, Oregon, and Department of Behavioral Neuroscience, Oregon Health & Science University, Portland, Oregon
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5
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Chen R, Ferris MJ, Wang S. Dopamine D2 autoreceptor interactome: Targeting the receptor complex as a strategy for treatment of substance use disorder. Pharmacol Ther 2020; 213:107583. [PMID: 32473160 PMCID: PMC7434700 DOI: 10.1016/j.pharmthera.2020.107583] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2019] [Accepted: 05/11/2020] [Indexed: 02/06/2023]
Abstract
Dopamine D2 autoreceptors (D2ARs), located in somatodendritic and axon terminal compartments of dopamine (DA) neurons, function to provide a negative feedback regulatory control on DA neuron firing, DA synthesis, reuptake and release. Dysregulation of D2AR-mediated DA signaling is implicated in vulnerability to substance use disorder (SUD). Due to the extreme low abundance of D2ARs compared to postsynaptic D2 receptors (D2PRs) and the lack of experimental tools to differentiate the signaling of D2ARs from D2PRs, the regulation of D2ARs by drugs of abuse is poorly understood. The recent availability of conditional D2AR knockout mice and newly developed virus-mediated gene delivery approaches have provided means to specifically study the function of D2ARs at the molecular, cellular and behavioral levels. There is a growing revelation of novel mechanisms and new proteins that mediate D2AR activity, suggesting that D2ARs act cooperatively with an array of membrane and intracellular proteins to tightly control DA transmission. This review highlights D2AR-interacting partners including transporters, G-protein-coupled receptors, ion channels, intracellular signaling modulators, and protein kinases. The complexity of the D2AR interaction network illustrates the functional divergence of D2ARs. Pharmacological targeting of multiple D2AR-interacting partners may be more effective to restore disrupted DA homeostasis by drugs of abuse.
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Affiliation(s)
- Rong Chen
- Dept. of Physiology & Pharmacology, Wake Forest School of Medicine, Winston Salem, NC 27157, United States of America; Center for the Neurobiology of Addiction Treatment, Wake Forest School of Medicine, Winston Salem, NC 27157, United States of America.
| | - Mark J Ferris
- Dept. of Physiology & Pharmacology, Wake Forest School of Medicine, Winston Salem, NC 27157, United States of America; Center for the Neurobiology of Addiction Treatment, Wake Forest School of Medicine, Winston Salem, NC 27157, United States of America
| | - Shiyu Wang
- Dept. of Physiology & Pharmacology, Wake Forest School of Medicine, Winston Salem, NC 27157, United States of America
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Robinson BG, Condon AF, Radl D, Borrelli E, Williams JT, Neve KA. Cocaine-induced adaptation of dopamine D2S, but not D2L autoreceptors. eLife 2017; 6. [PMID: 29154756 PMCID: PMC5695907 DOI: 10.7554/elife.31924] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2017] [Accepted: 11/13/2017] [Indexed: 12/12/2022] Open
Abstract
The dopamine D2 receptor has two splice variants, D2S (Short) and D2L (Long). In dopamine neurons, both variants can act as autoreceptors to regulate neuronal excitability and dopamine release, but the roles of each variant are incompletely characterized. In a previous study we used viral receptor expression in D2 receptor knockout mice to show distinct effects of calcium signaling on D2S and D2L autoreceptor function (Gantz et al., 2015). However, the cocaine-induced plasticity of D2 receptor desensitization observed in wild type mice was not recapitulated with this method of receptor expression. Here we use mice with genetic knockouts of either the D2S or D2L variant to investigate cocaine-induced plasticity in D2 receptor signaling. Following a single in vivo cocaine exposure, the desensitization of D2 receptors from neurons expressing only the D2S variant was reduced. This did not occur in D2L-expressing neurons, indicating differential drug-induced plasticity between the variants.
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Affiliation(s)
- Brooks G Robinson
- The Vollum Institute, Oregon Health & Science University, Portland, United States
| | - Alec F Condon
- The Vollum Institute, Oregon Health & Science University, Portland, United States
| | - Daniela Radl
- Department of Microbiology and Molecular Genetics, University of California, Irvine, Irvine, United States
| | - Emiliana Borrelli
- Department of Microbiology and Molecular Genetics, University of California, Irvine, Irvine, United States
| | - John T Williams
- The Vollum Institute, Oregon Health & Science University, Portland, United States
| | - Kim A Neve
- Research Service, VA Portland Health Care System, Portland, United States.,Department of Behavioral Neuroscience, Oregon Health & Science University, Portland, United States
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7
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Hermann A, Donato R, Weiger TM, Chazin WJ. S100 calcium binding proteins and ion channels. Front Pharmacol 2012; 3:67. [PMID: 22539925 PMCID: PMC3336106 DOI: 10.3389/fphar.2012.00067] [Citation(s) in RCA: 57] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2012] [Accepted: 04/03/2012] [Indexed: 12/23/2022] Open
Abstract
S100 Ca(2+)-binding proteins have been associated with a multitude of intracellular Ca(2+)-dependent functions including regulation of the cell cycle, cell differentiation, cell motility and apoptosis, modulation of membrane-cytoskeletal interactions, transduction of intracellular Ca(2+) signals, and in mediating learning and memory. S100 proteins are fine tuned to read the intracellular free Ca(2+) concentration and affect protein phosphorylation, which makes them candidates to modulate certain ion channels and neuronal electrical behavior. Certain S100s are secreted from cells and are found in extracellular fluids where they exert unique extracellular functions. In addition to their neurotrophic activity, some S100 proteins modulate neuronal electrical discharge activity and appear to act directly on ion channels. The first reports regarding these effects suggested S100-mediated alterations in Ca(2+) fluxes, K(+) currents, and neuronal discharge activity. Recent reports revealed direct and indirect interactions with Ca(2+), K(+), Cl(-), and ligand activated channels. This review focuses on studies of the physical and functional interactions of S100 proteins and ion channels.
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Affiliation(s)
- Anton Hermann
- Division of Cellular and Molecular Neurobiology, Department of Cell Biology, University of SalzburgSalzburg, Austria
| | - Rosario Donato
- Department of Experimental Medicine and Biochemical Sciences, University of PerugiaPerugia, Italy
| | - Thomas M. Weiger
- Division of Cellular and Molecular Neurobiology, Department of Cell Biology, University of SalzburgSalzburg, Austria
| | - Walter J. Chazin
- Departments of Biochemistry and Chemistry, Center for Structural Biology, Vanderbilt UniversityNashville, TN, USA
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Maurice P, Guillaume JL, Benleulmi-Chaachoua A, Daulat AM, Kamal M, Jockers R. GPCR-Interacting Proteins, Major Players of GPCR Function. PHARMACOLOGY OF G PROTEIN COUPLED RECEPTORS 2011; 62:349-80. [DOI: 10.1016/b978-0-12-385952-5.00001-4] [Citation(s) in RCA: 44] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
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9
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Current perspectives on the selective regulation of dopamine D2 and D3 receptors. Arch Pharm Res 2010; 33:1521-38. [DOI: 10.1007/s12272-010-1005-8] [Citation(s) in RCA: 65] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2010] [Revised: 08/20/2010] [Accepted: 08/20/2010] [Indexed: 01/07/2023]
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10
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Feldkamp MD, O'Donnell SE, Yu L, Shea MA. Allosteric effects of the antipsychotic drug trifluoperazine on the energetics of calcium binding by calmodulin. Proteins 2010; 78:2265-82. [PMID: 20544963 DOI: 10.1002/prot.22739] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Trifluoperazine (TFP; Stelazine) is an antagonist of calmodulin (CaM), an essential regulator of calcium-dependent signal transduction. Reports differ regarding whether, or where, TFP binds to apo CaM. Three crystallographic structures (1CTR, 1A29, and 1LIN) show TFP bound to (Ca(2+))(4)-CaM in ratios of 1, 2, or 4 TFP per CaM. In all of these, CaM domains adopt the "open" conformation seen in CaM-kinase complexes having increased calcium affinity. Most reports suggest TFP also increases calcium affinity of CaM. To compare TFP binding to apo CaM and (Ca(2+))(4)-CaM and explore differential effects on the N- and C-domains of CaM, stoichiometric TFP titrations of CaM were monitored by (15)N-HSQC NMR. Two TFP bound to apo CaM, whereas four bound to (Ca(2+))(4)-CaM. In both cases, the preferred site was in the C-domain. During the titrations, biphasic responses for some resonances suggested intersite interactions. TFP-binding sites in apo CaM appeared distinct from those in (Ca(2+))(4)-CaM. In equilibrium calcium titrations at defined ratios of TFP:CaM, TFP reduced calcium affinity at most levels tested; this is similar to the effect of many IQ-motifs on CaM. However, at the highest level tested, TFP raised the calcium affinity of the N-domain of CaM. A model of conformational switching is proposed to explain how TFP can exert opposing allosteric effects on calcium affinity by binding to different sites in the "closed," "semi-open," and "open" domains of CaM. In physiological processes, apo CaM, as well as (Ca(2+))(4)-CaM, needs to be considered a potential target of drug action.
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Affiliation(s)
- Michael D Feldkamp
- Department of Biochemistry, Roy J. and Lucille A. Carver College of Medicine, University of Iowa, Iowa City, Iowa 52242-1109, USA
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11
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Heart-type fatty acid binding protein regulates dopamine D2 receptor function in mouse brain. J Neurosci 2010; 30:3146-55. [PMID: 20181611 DOI: 10.1523/jneurosci.4140-09.2010] [Citation(s) in RCA: 79] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023] Open
Abstract
Fatty acid binding proteins (FABPs) are essential for energy production and long-chain polyunsaturated fatty acid-related signaling in the brain and other tissues. Of various FABPs, heart-type fatty acid binding protein (H-FABP, FABP3) is highly expressed in neurons of mature brain and plays a role in arachidonic acid incorporation into brain and heart cells. However, the precise function of H-FABP in brain remains unclear. We previously demonstrated that H-FABP is associated with the dopamine D(2) receptor long isoform (D2LR) in vitro. Here, we confirm that H-FABP binds to dopamine D(2) receptor (D2R) in brain extracts and colocalizes immunohistochemically with D2R in the dorsal striatum. We show that H-FABP is highly expressed in acetylcholinergic interneurons and terminals of glutamatergic neurons in the dorsal striatum of mouse brain but absent in dopamine neuron terminals and spines in the same region. H-FABP knock-out (KO) mice showed lower responsiveness to methamphetamine-induced sensitization and enhanced haloperidol-induced catalepsy compared with wild-type mice, indicative of D2R dysfunction. Consistent with the latter, aberrant increased acetylcholine (ACh) release and depolarization-induced glutamate (Glu) release were observed in the dorsal striatum of H-FABP KO mice. Furthermore, phosphorylation of CaMKII (Ca(2+)/calmodulin-dependent protein kinase II) and ERK (extracellular signal-regulated kinase) was significantly increased in the dorsal striatum. We confirmed elevated ERK phosphorylation following quinpirole-mediated D2R stimulation in H-FABP-overexpressing SHSY-5Y human neuroblastoma cells. Together, H-FABP is highly expressed in ACh interneurons and glutamatergic terminals, thereby regulating dopamine D2R function in the striatum.
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12
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Ritter SL, Hall RA. Fine-tuning of GPCR activity by receptor-interacting proteins. Nat Rev Mol Cell Biol 2009; 10:819-30. [PMID: 19935667 DOI: 10.1038/nrm2803] [Citation(s) in RCA: 349] [Impact Index Per Article: 23.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
G protein-coupled receptors (GPCRs) mediate physiological responses to various ligands, such as hormones, neurotransmitters and sensory stimuli. The signalling and trafficking properties of GPCRs are often highly malleable depending on the cellular context. Such fine-tuning of GPCR function can be attributed in many cases to receptor-interacting proteins that are differentially expressed in distinct cell types. In some cases these GPCR-interacting partners directly mediate receptor signalling, whereas in other cases they act mainly as scaffolds to modulate G protein-mediated signalling. Furthermore, GPCR-interacting proteins can have a big impact on the regulation of GPCR trafficking, localization and/or pharmacological properties.
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Affiliation(s)
- Stefanie L Ritter
- Department of Pharmacology, Emory University School of Medicine, Atlanta, Georgia 30322, USA
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13
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Xiao MF, Xu JC, Tereshchenko Y, Novak D, Schachner M, Kleene R. Neural cell adhesion molecule modulates dopaminergic signaling and behavior by regulating dopamine D2 receptor internalization. J Neurosci 2009; 29:14752-63. [PMID: 19940170 PMCID: PMC6666007 DOI: 10.1523/jneurosci.4860-09.2009] [Citation(s) in RCA: 63] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2009] [Accepted: 10/01/2009] [Indexed: 12/15/2022] Open
Abstract
The dopaminergic system plays an important role in the etiology of schizophrenia, and most antipsychotic drugs exert their functions by blocking dopamine D(2) receptors (D(2)Rs). Since the signaling strength mediated by D(2)Rs is regulated by internalization and degradation processes, it is crucial to identify molecules that modulate D(2)R localization at the cell surface. Here, we show that the neural cell adhesion molecule (NCAM) promotes D(2)R internalization/desensitization and subsequent degradation via direct interaction with a short peptide in the third intracellular loop of the D(2)R. NCAM deficiency in mice leads to increased numbers of D(2)Rs at the cell surface and augmented D(2)R signaling as a result of impaired D(2)R internalization. Furthermore, NCAM-deficient mice show higher sensitivity to the psychostimulant apomorphine and exaggerated activity of dopamine-related locomotor behavior. These results demonstrate that, in addition to its classical function in cell adhesion, NCAM is involved in regulating the trafficking of the neurotransmitter receptor D(2)R as well as receptor-mediated signaling and behavior, thus implicating NCAM as modulator of the dopaminergic system and a potential pharmacological target for dopamine-related neurological and psychiatric disorders.
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Affiliation(s)
- Mei-Fang Xiao
- Zentrum für Molekulare Neurobiologie, Universitätsklinikum Hamburg-Eppendorf, D-20246 Hamburg, Germany
| | - Jin-Chong Xu
- Zentrum für Molekulare Neurobiologie, Universitätsklinikum Hamburg-Eppendorf, D-20246 Hamburg, Germany
| | - Yuliya Tereshchenko
- Zentrum für Molekulare Neurobiologie, Universitätsklinikum Hamburg-Eppendorf, D-20246 Hamburg, Germany
| | - Daniel Novak
- Zentrum für Molekulare Neurobiologie, Universitätsklinikum Hamburg-Eppendorf, D-20246 Hamburg, Germany
| | - Melitta Schachner
- Zentrum für Molekulare Neurobiologie, Universitätsklinikum Hamburg-Eppendorf, D-20246 Hamburg, Germany
- Keck Center for Collaborative Neuroscience and Department of Cell Biology and Neuroscience, Rutgers University, Piscataway, New Jersey 08854, and
- Center for Neuroscience, Shantou University Medical College, Shantou 515041, China
| | - Ralf Kleene
- Zentrum für Molekulare Neurobiologie, Universitätsklinikum Hamburg-Eppendorf, D-20246 Hamburg, Germany
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Navarro G, Aymerich MS, Marcellino D, Cortés A, Casadó V, Mallol J, Canela EI, Agnati L, Woods AS, Fuxe K, Lluís C, Lanciego JL, Ferré S, Franco R. Interactions between calmodulin, adenosine A2A, and dopamine D2 receptors. J Biol Chem 2009; 284:28058-28068. [PMID: 19632986 DOI: 10.1074/jbc.m109.034231] [Citation(s) in RCA: 49] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
The Ca(2+)-binding protein calmodulin (CaM) has been shown to bind directly to cytoplasmic domains of some G protein-coupled receptors, including the dopamine D(2) receptor. CaM binds to the N-terminal portion of the long third intracellular loop of the D(2) receptor, within an Arg-rich epitope that is also involved in the binding to G(i/o) proteins and to the adenosine A(2A) receptor, with the formation of A(2A)-D(2) receptor heteromers. In the present work, by using proteomics and bioluminescence resonance energy transfer (BRET) techniques, we provide evidence for the binding of CaM to the A(2A) receptor. By using BRET and sequential resonance energy transfer techniques, evidence was obtained for CaM-A(2A)-D(2) receptor oligomerization. BRET competition experiments indicated that, in the A(2A)-D(2) receptor heteromer, CaM binds preferentially to a proximal C terminus epitope of the A(2A) receptor. Furthermore, Ca(2+) was found to induce conformational changes in the CaM-A(2A)-D(2) receptor oligomer and to selectively modulate A(2A) and D(2) receptor-mediated MAPK signaling in the A(2A)-D(2) receptor heteromer. These results may have implications for basal ganglia disorders, since A(2A)-D(2) receptor heteromers are being considered as a target for anti-parkinsonian agents.
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Affiliation(s)
- Gemma Navarro
- Institut d'Investigacions Biomèdiques August Pi i Sunyer, Centro de Investigación Biomédica en Red Sobre Enfermedades Neurodegenerativas, and Department of Biochemistry and Molecular Biology, Faculty of Biology, University of Barcelona, 08028 Barcelona, Spain
| | - Marisol S Aymerich
- Centro de Investigación Médica Aplicada Neurociencias (CIMA), Universidad de Navarra, Avda. Pio XII 55, 31008 Pamplona, Spain
| | - Daniel Marcellino
- Department of Neuroscience, Karolinska Institute, 17177 Stockholm, Sweden
| | - Antoni Cortés
- Institut d'Investigacions Biomèdiques August Pi i Sunyer, Centro de Investigación Biomédica en Red Sobre Enfermedades Neurodegenerativas, and Department of Biochemistry and Molecular Biology, Faculty of Biology, University of Barcelona, 08028 Barcelona, Spain
| | - Vicent Casadó
- Institut d'Investigacions Biomèdiques August Pi i Sunyer, Centro de Investigación Biomédica en Red Sobre Enfermedades Neurodegenerativas, and Department of Biochemistry and Molecular Biology, Faculty of Biology, University of Barcelona, 08028 Barcelona, Spain
| | - Josefa Mallol
- Institut d'Investigacions Biomèdiques August Pi i Sunyer, Centro de Investigación Biomédica en Red Sobre Enfermedades Neurodegenerativas, and Department of Biochemistry and Molecular Biology, Faculty of Biology, University of Barcelona, 08028 Barcelona, Spain
| | - Enric I Canela
- Institut d'Investigacions Biomèdiques August Pi i Sunyer, Centro de Investigación Biomédica en Red Sobre Enfermedades Neurodegenerativas, and Department of Biochemistry and Molecular Biology, Faculty of Biology, University of Barcelona, 08028 Barcelona, Spain
| | - Luigi Agnati
- Department of Neuroscience, Karolinska Institute, 17177 Stockholm, Sweden
| | - Amina S Woods
- National Institute on Drug Abuse, Intramural Research Program, National Institutes of Health, Baltimore, Maryland 21224
| | - Kjell Fuxe
- Department of Neuroscience, Karolinska Institute, 17177 Stockholm, Sweden
| | - Carmen Lluís
- Institut d'Investigacions Biomèdiques August Pi i Sunyer, Centro de Investigación Biomédica en Red Sobre Enfermedades Neurodegenerativas, and Department of Biochemistry and Molecular Biology, Faculty of Biology, University of Barcelona, 08028 Barcelona, Spain
| | - Jose Luis Lanciego
- Centro de Investigación Médica Aplicada Neurociencias (CIMA), Universidad de Navarra, Avda. Pio XII 55, 31008 Pamplona, Spain
| | - Sergi Ferré
- National Institute on Drug Abuse, Intramural Research Program, National Institutes of Health, Baltimore, Maryland 21224
| | - Rafael Franco
- Institut d'Investigacions Biomèdiques August Pi i Sunyer, Centro de Investigación Biomédica en Red Sobre Enfermedades Neurodegenerativas, and Department of Biochemistry and Molecular Biology, Faculty of Biology, University of Barcelona, 08028 Barcelona, Spain; Centro de Investigación Médica Aplicada Neurociencias (CIMA), Universidad de Navarra, Avda. Pio XII 55, 31008 Pamplona, Spain.
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15
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Brain receptor mosaics and their intramembrane receptor-receptor interactions: molecular integration in transmission and novel targets for drug development. J Acupunct Meridian Stud 2009; 2:1-25. [PMID: 20633470 DOI: 10.1016/s2005-2901(09)60011-x] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2008] [Accepted: 01/06/2009] [Indexed: 11/21/2022] Open
Abstract
The concept of intramembrane receptor-receptor interactions and evidence for their existence was introduced by Agnati and Fuxe in 1980/81 suggesting the existence of heteromerization of receptors. In 1982, they proposed the existence of aggregates of multiple receptors in the plasma membrane and coined the term receptor mosaics (RM). In this way, cell signaling becomes a branched process beginning at the level of receptor recognition at the plasma membrane where receptors can directly modify the ligand recognition and signaling capacity of the receptors within a RM. Receptor-receptor interactions in RM are classified as operating either with classical cooperativity, when consisting of homomers or heteromers of similar receptor subtypes having the same transmitter, or non-classical cooperativity, when consisting of heteromers. It has been shown that information processing within a RM depends not only on its receptor composition, but also on the topology and the order of receptor activation determined by the concentrations of the ligands and the receptor properties. The general function of RM has also been demonstrated to depend on allosteric regulators (e.g., homocysteine) of the receptor subtypes present. RM as integrative nodes for receptor-receptor interactions in conjunction with membrane associated proteins may form horizontal molecular networks in the plasma membrane coordinating the activity of multiple effector systems modulating the excitability and gene expression of the cells. The key role of electrostatic epitope-epitope interactions will be discussed for the formation of the RM. These interactions probably represent a general molecular mechanism for receptor-receptor interactions and, without a doubt, indicate a role for phosphorylation-dephosphorylation events in these interactions. The novel therapeutic aspects given by the RMs will be discussed in the frame of molecular neurology and psychiatry and combined drug therapy appears as the future way to go.
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16
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Falktoft B, Georg B, Fahrenkrug J. Calmodulin interacts with PAC1 and VPAC2 receptors and regulates PACAP-induced FOS expression in human neuroblastoma cells. Neuropeptides 2009; 43:53-61. [PMID: 19269029 DOI: 10.1016/j.npep.2009.02.001] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/07/2009] [Revised: 02/05/2009] [Accepted: 02/05/2009] [Indexed: 10/21/2022]
Abstract
The neuropeptide pituitary adenylate cyclase-activating polypeptide (PACAP) mediates its physiological functions through activation of PAC1, VPAC1 and VPAC2 receptors, and the ubiquitous Ca(2+)-sensor calmodulin has been implicated in PACAP-induced signaling. The immediate early response gene FOS is a well-known marker of neuronal activation, so we used a human neuroblastoma cell line NB-1 to explore the role of calmodulin in PACAP-induced FOS gene expression. We observed both short-term and prolonged altered PACAP-mediated activation of the FOS gene in the presence of the calmodulin-antagonist W-7. NB-1 cells were shown to express PAC1 and VPAC2 receptors, and immunoprecipitation of both receptors displayed a co-association with calmodulin in the absence of Ca(2+). Our findings indicate a novel mechanism of calmodulin in regulating PACAP signaling by possible interaction with the inactive state of PAC1 and VPAC2 receptors.
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Affiliation(s)
- Birgitte Falktoft
- Department of Clinical Biochemistry, Bispebjerg Hospital, Faculty of Health Sciences, University of Copenhagen, Copenhagen, Denmark.
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17
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Lan H, Liu Y, Bell MI, Gurevich VV, Neve KA. A dopamine D2 receptor mutant capable of G protein-mediated signaling but deficient in arrestin binding. Mol Pharmacol 2008; 75:113-23. [PMID: 18809670 DOI: 10.1124/mol.108.050534] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Arrestins mediate G protein-coupled receptor desensitization, internalization, and signaling. Dopamine D(2) and D(3) receptors have similar structures but distinct characteristics of interaction with arrestins. The goals of this study were to compare arrestin-binding determinants in D(2) and D(3) receptors other than phosphorylation sites and to create a D(2) receptor that is deficient in arrestin binding. We first assessed the ability of purified arrestins to bind to glutathione transferase (GST) fusion proteins containing the receptor third intracellular loops (IC3). Arrestin3 bound to IC3 of both D(2) and D(3) receptors, with the affinity and localization of the binding site indistinguishable between the receptor subtypes. Mutagenesis of the GST-IC3 fusion proteins identified an important determinant of the binding of arrestin3 in the N-terminal region of IC3. Alanine mutations of this determinant (IYIV212-215) in the full-length D(2) receptor generated a signaling-biased receptor with intact ligand binding and G-protein coupling and activation, but deficient in receptor-mediated arrestin3 translocation to the membrane, agonist-induced receptor internalization, and agonist-induced desensitization in human embryonic kidney 293 cells. This mutation also decreased arrestin-dependent activation of extracellular signal-regulated kinases. The finding that nonphosphorylated D(2)-IC3 and D(3)-IC3 have similar affinity for arrestin is consistent with previous suggestions that the differential effects of D(2) and D(3) receptor activation on membrane translocation of arrestin and receptor internalization are due, at least in part, to differential phosphorylation of the receptors. In addition, these results imply that the sequence IYIV212-215 at the N terminus of IC3 of the D(2) receptor is a key element of the arrestin binding site.
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Affiliation(s)
- Hongxiang Lan
- Department of Physiology & Pharmacology, Oregon Health & Science University, Portland, Oregon, USA
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18
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Woods AS, Marcellino D, Jackson SN, Franco R, Ferré S, Agnati LF, Fuxe K. How calmodulin interacts with the adenosine A(2A) and the dopamine D(2) receptors. J Proteome Res 2008; 7:3428-34. [PMID: 18590318 DOI: 10.1021/pr8001782] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Receptor heteromerization is a mechanism used by G protein-coupled receptors to diversify their properties and function. We previously demonstrated that these interactions occur through salt bridge formation between epitopes of the involved receptors. Recent studies claim that calmodulin (CaM) binds to an Arg-rich epitope located in the amino-terminus of the dopamine D(2) receptor third intracellular loop. This is the same epitope involved in adenosine A(2A)-D(2) receptor heteromerization, through Coulombic interaction between the Arg residues and a phosphorylated serine (pS) located in the medial segment of the C-terminus of the A(2A) receptor. Mass spectrometric analysis indicates that an electrostatic interaction involving the D(2) receptor Arg-rich epitope and several CaM acidic epitopes are mainly responsible for the D(2) receptor-CaM binding. CaM could also form multiple noncovalent complexes by means of electrostatic interactions with an epitope localized in the proximal segment of the C-terminus of the A(2A) receptor. Ca(2+) disrupted the binding of CaM to the D(2) but not to the A(2A) receptor epitope, and CaM disrupted the electrostatic interactions between the D(2) receptor epitope and the more distal A(2A) receptor epitope. A model is introduced with the possible functional implications of A(2A)-D(2)-CaM interactions. These in vitro findings imply a possible regulatory role for CaM in receptor heteromers formation.
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Affiliation(s)
- Amina S Woods
- National Institute on Drug Abuse, IRP, NIH, DHHS, Baltimore, MD 21224, USA.
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19
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Stanwood GD. Protein-protein interactions and dopamine D2 receptor signaling: a calcium connection. Mol Pharmacol 2008; 74:317-9. [PMID: 18511653 DOI: 10.1124/mol.108.049098] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
The third cytoplasmic loop is a crucial site of physical contact between some G protein-coupled receptors (GPCRs) and their respective G proteins. However, interactions not only occur among these proteins but also involve a number of additional protein binding partners. Modulation of these protein-protein interactions may represent an important new avenue of pharmacotherapy through which signaling of GPCRs can be modulated. In the current issue of Molecular Pharmacology, Liu et al. (p. 371) report that dopamine D(2) receptors interact with the Ca(2+) binding protein S100B. Using the third intracellular loop of the dopamine D(2) receptor as bait in a bacterial two-hybrid system, S100B was determined to be a potential binding partner. They used pull-down assays both in vitro and in vivo to confirm the interaction and define its specificity. Neither the D(3) nor the D(4) receptor expresses the motif conferring the interaction, and peptides based on the third intracellular loop of the D(3) receptor did not pull down S100B. Some groups might stop there, but Liu and colleagues moved on to demonstrate colocalization of the D(2) receptor and S100B by immunostaining. Functional assays were then used to show that coexpression of S100B with the D(2) receptor increases the ability of D(2) receptors to activate ERK and to inhibit adenylyl cyclase. These data suggest that S100B coexpression may serve as an important mediator of D(2) receptor signaling efficacy in the brain. These interactions contribute to cellular, regional, and developmental differences in D(2) receptor activation.
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Affiliation(s)
- Gregg D Stanwood
- Department of Pharmacology, Vanderbilt Kennedy Center, 23rd Ave South, 476 RRB, Nashville TN 37232-6600, USA.
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20
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Liu Y, Buck DC, Neve KA. Novel interaction of the dopamine D2 receptor and the Ca2+ binding protein S100B: role in D2 receptor function. Mol Pharmacol 2008; 74:371-8. [PMID: 18445708 DOI: 10.1124/mol.108.044925] [Citation(s) in RCA: 48] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023] Open
Abstract
S100B is a calcium-binding protein with both extracellular and intracellular regulatory activities in the mammalian brain. We have identified a novel interaction between S100B and the dopamine D(2) receptor. Our results also suggest that the binding of S100B to the dopamine D(2) receptor enhances receptor signaling. This conclusion is based on the following observations: 1) S100B and the third cytoplasmic loop of the dopamine D(2) receptor interact in a bacterial two-hybrid system and in a poly-histidine pull-down assay; 2) immunoprecipitation of the D(2) receptor also precipitates FLAG-S100B from human embryonic kidney 293 cell homogenates and endogenous S100B from rat neostriatal homogenates; 3) S100B immunoreactivity was detected in cultured neostriatal neurons expressing the D(2) receptor; 4) a putative S100B binding motif is located at residues 233 to 240 of the D(2) receptor, toward the amino terminus of the third cytoplasmic loop. D(3)-IC3, which does not bind S100B, does not contain this motif; and 5) coexpression of S100B in D(2) receptor-expressing 293 cells selectively increased D(2) receptor stimulation of extracellular signal-regulated kinases and inhibition of adenylate cyclase.
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Affiliation(s)
- Yong Liu
- Department of Behavioral Neuroscience, Oregon Health & Science University, Portland, Oregon, USA
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21
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Kabbani N, Levenson R. A proteomic approach to receptor signaling: Molecular mechanisms and therapeutic implications derived from discovery of the dopamine D2 receptor signalplex. Eur J Pharmacol 2007; 572:83-93. [PMID: 17662712 DOI: 10.1016/j.ejphar.2007.06.059] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2007] [Revised: 06/14/2007] [Accepted: 06/18/2007] [Indexed: 12/23/2022]
Abstract
Recent research in cell signaling has shown that the assembly of G protein coupled receptors into signaling complexes or signalplexes represents the primary mechanism by which receptor-mediated signaling is established and maintained. In this review, we summarize the current state of knowledge regarding protein interactions that comprise the dopamine D2 receptor signalplex within the brain. Studies based on conventional and advanced two-hybrid methodologies, as well as bioinformatic and computational analysis of sequence information from completed genomes have demonstrated interactions between dopamine D2 receptors and a cohort of dopamine receptor interacting proteins (DRIPs). DRIP interactions appear to regulate key aspects of receptor function including the signaling and membrane trafficking of dopamine D2 receptors. Disruptions or modifications of the signalplex, using membrane permeant competing peptide or dominant negative approaches, may represent promising new strategies for the selective targeting of the dopamine D2 receptor in cells and in native tissue. DRIP interactions provide a novel platform for understanding the mechanisms of dopamine receptor signaling, and for the potential development of novel treatments for brain disease.
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Affiliation(s)
- Nadine Kabbani
- Department of Neuroscience, Pasteur Institute, 75015 Paris, France.
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