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Sumarac S, Youn J, Fearon C, Zivkovic L, Keerthi P, Flouty O, Popovic M, Hodaie M, Kalia S, Lozano A, Hutchison W, Fasano A, Milosevic L. Clinico-physiological correlates of Parkinson's disease from multi-resolution basal ganglia recordings. NPJ Parkinsons Dis 2024; 10:175. [PMID: 39261476 PMCID: PMC11391063 DOI: 10.1038/s41531-024-00773-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2024] [Accepted: 08/05/2024] [Indexed: 09/13/2024] Open
Abstract
Parkinson's disease (PD) has been associated with pathological neural activity within the basal ganglia. Herein, we analyzed resting-state single-neuron and local field potential (LFP) activities from people with PD who underwent awake deep brain stimulation surgery of the subthalamic nucleus (STN; n = 125) or globus pallidus internus (GPi; n = 44), and correlated rate-based and oscillatory features with UPDRSIII off-medication subscores. Rate-based single-neuron features did not correlate with PD symptoms. STN single-neuron and LFP low-beta (12-21 Hz) power and burst dynamics showed modest correlations with bradykinesia and rigidity severity, while STN spiketrain theta (4-8 Hz) power correlated modestly with tremor severity. GPi low- and high-beta (21-30 Hz) power and burst dynamics correlated moderately with bradykinesia and axial symptom severity. These findings suggest that elevated single-neuron and LFP oscillations may be linked to symptoms, though modest correlations imply that the pathophysiology of PD may extend beyond resting-state beta oscillations.
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Affiliation(s)
- Srdjan Sumarac
- Krembil Brain Institute, University Health Network, Toronto, ON, Canada
- Institute of Biomedical Engineering, University of Toronto, Toronto, ON, Canada
| | - Jinyoung Youn
- Krembil Brain Institute, University Health Network, Toronto, ON, Canada
- Edmond J. Safra Program in Parkinson's Disease, Morton and Gloria Shulman Movement Disorders Clinic, Toronto Western Hospital, Toronto, ON, Canada
- Department of Neurology, University of Toronto, Toronto, ON, Canada
| | - Conor Fearon
- Krembil Brain Institute, University Health Network, Toronto, ON, Canada
- Edmond J. Safra Program in Parkinson's Disease, Morton and Gloria Shulman Movement Disorders Clinic, Toronto Western Hospital, Toronto, ON, Canada
- Department of Neurology, University of Toronto, Toronto, ON, Canada
| | - Luka Zivkovic
- Krembil Brain Institute, University Health Network, Toronto, ON, Canada
- Institute of Biomedical Engineering, University of Toronto, Toronto, ON, Canada
| | - Prerana Keerthi
- Krembil Brain Institute, University Health Network, Toronto, ON, Canada
- Institute of Biomedical Engineering, University of Toronto, Toronto, ON, Canada
| | - Oliver Flouty
- Krembil Brain Institute, University Health Network, Toronto, ON, Canada
- Institute of Medical Sciences, University of Toronto, Toronto, ON, Canada
- Department of Surgery, University of Toronto, Toronto, ON, Canada
- Department of Neurosurgery and Brain Repair, University of South Florida, Tampa, FL, USA
| | - Milos Popovic
- Institute of Biomedical Engineering, University of Toronto, Toronto, ON, Canada
- KITE, University Health Network, Toronto, ON, Canada
- Center for Advancing Neurotechnological Innovation to Application (CRANIA), Toronto, ON, Canada
| | - Mojgan Hodaie
- Krembil Brain Institute, University Health Network, Toronto, ON, Canada
- Institute of Medical Sciences, University of Toronto, Toronto, ON, Canada
- Department of Surgery, University of Toronto, Toronto, ON, Canada
- Center for Advancing Neurotechnological Innovation to Application (CRANIA), Toronto, ON, Canada
| | - Suneil Kalia
- Krembil Brain Institute, University Health Network, Toronto, ON, Canada
- Department of Surgery, University of Toronto, Toronto, ON, Canada
- KITE, University Health Network, Toronto, ON, Canada
- Center for Advancing Neurotechnological Innovation to Application (CRANIA), Toronto, ON, Canada
| | - Andres Lozano
- Krembil Brain Institute, University Health Network, Toronto, ON, Canada
- Institute of Medical Sciences, University of Toronto, Toronto, ON, Canada
- Department of Surgery, University of Toronto, Toronto, ON, Canada
- Center for Advancing Neurotechnological Innovation to Application (CRANIA), Toronto, ON, Canada
| | - William Hutchison
- Krembil Brain Institute, University Health Network, Toronto, ON, Canada
- Department of Surgery, University of Toronto, Toronto, ON, Canada
- Center for Advancing Neurotechnological Innovation to Application (CRANIA), Toronto, ON, Canada
- Department of Physiology, University of Toronto, Toronto, ON, Canada
| | - Alfonso Fasano
- Krembil Brain Institute, University Health Network, Toronto, ON, Canada
- Edmond J. Safra Program in Parkinson's Disease, Morton and Gloria Shulman Movement Disorders Clinic, Toronto Western Hospital, Toronto, ON, Canada
- Department of Neurology, University of Toronto, Toronto, ON, Canada
- Institute of Medical Sciences, University of Toronto, Toronto, ON, Canada
- KITE, University Health Network, Toronto, ON, Canada
- Center for Advancing Neurotechnological Innovation to Application (CRANIA), Toronto, ON, Canada
| | - Luka Milosevic
- Krembil Brain Institute, University Health Network, Toronto, ON, Canada.
- Institute of Biomedical Engineering, University of Toronto, Toronto, ON, Canada.
- Institute of Medical Sciences, University of Toronto, Toronto, ON, Canada.
- KITE, University Health Network, Toronto, ON, Canada.
- Center for Advancing Neurotechnological Innovation to Application (CRANIA), Toronto, ON, Canada.
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Tsuboi D, Otsuka T, Shimomura T, Faruk MO, Yamahashi Y, Amano M, Funahashi Y, Kuroda K, Nishioka T, Kobayashi K, Sano H, Nagai T, Yamada K, Tzingounis AV, Nambu A, Kubo Y, Kawaguchi Y, Kaibuchi K. Dopamine drives neuronal excitability via KCNQ channel phosphorylation for reward behavior. Cell Rep 2022; 40:111309. [PMID: 36070693 DOI: 10.1016/j.celrep.2022.111309] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2022] [Revised: 06/22/2022] [Accepted: 08/12/2022] [Indexed: 11/25/2022] Open
Abstract
Dysfunctional dopamine signaling is implicated in various neuropsychological disorders. Previously, we reported that dopamine increases D1 receptor (D1R)-expressing medium spiny neuron (MSN) excitability and firing rates in the nucleus accumbens (NAc) via the PKA/Rap1/ERK pathway to promote reward behavior. Here, the results show that the D1R agonist, SKF81297, inhibits KCNQ-mediated currents and increases D1R-MSN firing rates in murine NAc slices, which is abolished by ERK inhibition. In vitro ERK phosphorylates KCNQ2 at Ser414 and Ser476; in vivo, KCNQ2 is phosphorylated downstream of dopamine signaling in NAc slices. Conditional deletion of Kcnq2 in D1R-MSNs reduces the inhibitory effect of SKF81297 on KCNQ channel activity, while enhancing neuronal excitability and cocaine-induced reward behavior. These effects are restored by wild-type, but not phospho-deficient KCNQ2. Hence, D1R-ERK signaling controls MSN excitability via KCNQ2 phosphorylation to regulate reward behavior, making KCNQ2 a potential therapeutical target for psychiatric diseases with a dysfunctional reward circuit.
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Affiliation(s)
- Daisuke Tsuboi
- Division of Cell Biology, International Center for Brain Science, Fujita Health University, 1-98 Dengakugakubo, Kusukake-cho, Toyoake, Aichi 470-1192, Japan
| | - Takeshi Otsuka
- Division of Cerebral Circuitry, National Institute for Physiological Sciences, 5-1 Higashiyama, Myodaiji, Okazaki, Aichi, 444-8787, Japan
| | - Takushi Shimomura
- Division of Biophysics and Neurobiology, National Institute for Physiological Sciences, 38 Nishigonaka, Myodaiji, Okazaki, Aichi 444-8585, Japan
| | - Md Omar Faruk
- Department of Cell Pharmacology, Graduate School of Medicine, Nagoya University, 65 Tsuruma-cho, Showa-ku, Nagoya, Aichi 466-8550, Japan
| | - Yukie Yamahashi
- Division of Cell Biology, International Center for Brain Science, Fujita Health University, 1-98 Dengakugakubo, Kusukake-cho, Toyoake, Aichi 470-1192, Japan
| | - Mutsuki Amano
- Department of Cell Pharmacology, Graduate School of Medicine, Nagoya University, 65 Tsuruma-cho, Showa-ku, Nagoya, Aichi 466-8550, Japan
| | - Yasuhiro Funahashi
- Division of Cell Biology, International Center for Brain Science, Fujita Health University, 1-98 Dengakugakubo, Kusukake-cho, Toyoake, Aichi 470-1192, Japan
| | - Keisuke Kuroda
- Department of Cell Pharmacology, Graduate School of Medicine, Nagoya University, 65 Tsuruma-cho, Showa-ku, Nagoya, Aichi 466-8550, Japan
| | - Tomoki Nishioka
- Division of Cell Biology, International Center for Brain Science, Fujita Health University, 1-98 Dengakugakubo, Kusukake-cho, Toyoake, Aichi 470-1192, Japan
| | - Kenta Kobayashi
- Section of Viral Vector Development, Center for Genetic Analysis of Behavior, National Institute for Physiological Sciences, 38 Nishigonaka, Myodaiji, Okazaki, Aichi 444-8585, Japan
| | - Hiromi Sano
- Division of System Neurophysiology, National Institute for Physiological Sciences and Department of Physiological Sciences, Sokendai, 38 Nishigonaka, Myodaiji, Okazaki, Aichi 444-8585, Japan; Division of Behavioral Neuropharmacology, International Center for Brain Science, Fujita Health University, 1-98 Dengakugakubo, Kusukake-cho, Toyoake, Aichi 470-1192, Japan
| | - Taku Nagai
- Division of Behavioral Neuropharmacology, International Center for Brain Science, Fujita Health University, 1-98 Dengakugakubo, Kusukake-cho, Toyoake, Aichi 470-1192, Japan
| | - Kiyofumi Yamada
- Department of Neuropsychopharmacology and Hospital Pharmacy, Graduate School of Medicine, Nagoya University, 65 Tsuruma-cho, Showa-ku, Nagoya, Aichi 466-8560, Japan
| | | | - Atsushi Nambu
- Division of System Neurophysiology, National Institute for Physiological Sciences and Department of Physiological Sciences, Sokendai, 38 Nishigonaka, Myodaiji, Okazaki, Aichi 444-8585, Japan
| | - Yoshihiro Kubo
- Division of Biophysics and Neurobiology, National Institute for Physiological Sciences, 38 Nishigonaka, Myodaiji, Okazaki, Aichi 444-8585, Japan
| | - Yasuo Kawaguchi
- Division of Cerebral Circuitry, National Institute for Physiological Sciences, 5-1 Higashiyama, Myodaiji, Okazaki, Aichi, 444-8787, Japan; Brain Science Institute, Tamagawa University, Machida, Tokyo 194-8610, Japan
| | - Kozo Kaibuchi
- Division of Cell Biology, International Center for Brain Science, Fujita Health University, 1-98 Dengakugakubo, Kusukake-cho, Toyoake, Aichi 470-1192, Japan; Department of Cell Pharmacology, Graduate School of Medicine, Nagoya University, 65 Tsuruma-cho, Showa-ku, Nagoya, Aichi 466-8550, Japan.
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McGregor MM, Nelson AB. Circuit Mechanisms of Parkinson's Disease. Neuron 2019; 101:1042-1056. [PMID: 30897356 DOI: 10.1016/j.neuron.2019.03.004] [Citation(s) in RCA: 278] [Impact Index Per Article: 55.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2018] [Revised: 02/11/2019] [Accepted: 03/01/2019] [Indexed: 12/27/2022]
Abstract
Parkinson's disease (PD) is a complex, multi-system neurodegenerative disorder. The second most common neurodegenerative disorder after Alzheimer's disease, it affects approximately 1% of adults over age 60. Diagnosis follows the development of one or more of the core motor features of the disease, including tremor, slowing of movement (bradykinesia), and rigidity. However, there are numerous other motor and nonmotor disease manifestations. Many PD symptoms result directly from neurodegeneration; others are driven by aberrant activity patterns in surviving neurons. This latter phenomenon, PD circuit dysfunction, is an area of intense study, as it likely underlies our ability to treat many disease symptoms in the face of (currently) irreversible neurodegeneration. This Review will discuss key clinical features of PD and their basis in neural circuit dysfunction. We will first review important disease symptoms and some of the responsible neuropathology. We will then describe the basal ganglia-thalamocortical circuit, the major locus of PD-related circuit dysfunction, and some of the models that have influenced its study. We will review PD-related changes in network activity, subdividing findings into those that touch on the rate, rhythm, or synchronization of neurons. Finally, we suggest some critical remaining questions for the field and areas for new developments.
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Affiliation(s)
- Matthew M McGregor
- Neuroscience Graduate Program, UCSF, San Francisco, CA 94158, USA; Department of Neurology, UCSF, San Francisco, CA 94158, USA
| | - Alexandra B Nelson
- Neuroscience Graduate Program, UCSF, San Francisco, CA 94158, USA; Department of Neurology, UCSF, San Francisco, CA 94158, USA; Weill Institute for Neurosciences, UCSF, San Francisco, CA 94158, USA; Kavli Institute for Fundamental Neuroscience, UCSF, San Francisco, CA 94158, USA.
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4
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Yu-Taeger L, Ott T, Bonsi P, Tomczak C, Wassouf Z, Martella G, Sciamanna G, Imbriani P, Ponterio G, Tassone A, Schulze-Hentrich JM, Goodchild R, Riess O, Pisani A, Grundmann-Hauser K, Nguyen HP. Impaired dopamine- and adenosine-mediated signaling and plasticity in a novel rodent model for DYT25 dystonia. Neurobiol Dis 2019; 134:104634. [PMID: 31678405 DOI: 10.1016/j.nbd.2019.104634] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2019] [Revised: 09/19/2019] [Accepted: 10/02/2019] [Indexed: 12/20/2022] Open
Abstract
Dystonia is a neurological movement disorder characterized by sustained or intermittent involuntary muscle contractions. Loss-of-function mutations in the GNAL gene have been identified to be the cause of "isolated" dystonia DYT25. The GNAL gene encodes for the guanine nucleotide-binding protein G(olf) subunit alpha (Gαolf), which is mainly expressed in the olfactory bulb and the striatum and functions as a modulator during neurotransmission coupling with D1R and A2AR. Previously, heterozygous Gαolf -deficient mice (Gnal+/-) have been generated and showed a mild phenotype at basal condition. In contrast, homozygous deletion of Gnal in mice (Gnal-/-) resulted in a significantly reduced survival rate. In this study, using the CRISPR-Cas9 system we generated and characterized heterozygous Gnal knockout rats (Gnal+/-) with a 13 base pair deletion in the first exon of the rat Gnal splicing variant 2, a major isoform in both human and rat striatum. Gnal+/- rats showed early-onset phenotypes associated with impaired dopamine transmission, including reduction in locomotor activity, deficits in rotarod performance and an abnormal motor skill learning ability. At cellular and molecular level, we found down-regulated Arc expression, increased cell surface distribution of AMPA receptors, and the loss of D2R-dependent corticostriatal long-term depression (LTD) in Gnal+/- rats. Based on the evidence that D2R activity is normally inhibited by adenosine A2ARs, co-localized on the same population of striatal neurons, we show that blockade of A2ARs restores physiological LTD. This animal model may be a valuable tool for investigating Gαolf function and finding a suitable treatment for dystonia associated with deficient dopamine transmission.
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Affiliation(s)
- Libo Yu-Taeger
- Institute of Medical Genetics and Applied Genomics, University of Tuebingen, Tuebingen, Germany; Centre for Rare Diseases (ZSE), University of Tuebingen, Tuebingen, Germany
| | - Thomas Ott
- Institute of Medical Genetics and Applied Genomics, University of Tuebingen, Tuebingen, Germany; Core Facility Transgenic Animals, University Clinics Tuebingen, Tuebingen, Germany
| | - Paola Bonsi
- Laboratory of Neurophysiology and Plasticity, IRCCS Fondazione Santa Lucia, Rome, Italy
| | - Celina Tomczak
- Institute of Medical Genetics and Applied Genomics, University of Tuebingen, Tuebingen, Germany; Centre for Rare Diseases (ZSE), University of Tuebingen, Tuebingen, Germany
| | - Zinah Wassouf
- Institute of Medical Genetics and Applied Genomics, University of Tuebingen, Tuebingen, Germany; Centre for Rare Diseases (ZSE), University of Tuebingen, Tuebingen, Germany
| | - Giuseppina Martella
- Laboratory of Neurophysiology and Plasticity, IRCCS Fondazione Santa Lucia, Rome, Italy; Department of Systems Medicine, University of Rome Tor Vergata,Rome, Italy
| | - Giuseppe Sciamanna
- Laboratory of Neurophysiology and Plasticity, IRCCS Fondazione Santa Lucia, Rome, Italy; Department of Systems Medicine, University of Rome Tor Vergata,Rome, Italy
| | - Paola Imbriani
- Laboratory of Neurophysiology and Plasticity, IRCCS Fondazione Santa Lucia, Rome, Italy; Department of Systems Medicine, University of Rome Tor Vergata,Rome, Italy
| | - Giulia Ponterio
- Laboratory of Neurophysiology and Plasticity, IRCCS Fondazione Santa Lucia, Rome, Italy; Department of Systems Medicine, University of Rome Tor Vergata,Rome, Italy
| | - Annalisa Tassone
- Laboratory of Neurophysiology and Plasticity, IRCCS Fondazione Santa Lucia, Rome, Italy; Department of Systems Medicine, University of Rome Tor Vergata,Rome, Italy
| | - Julia M Schulze-Hentrich
- Institute of Medical Genetics and Applied Genomics, University of Tuebingen, Tuebingen, Germany; Centre for Rare Diseases (ZSE), University of Tuebingen, Tuebingen, Germany
| | - Rose Goodchild
- VIB-KU Leuven Center for Brain & Disease Research, Leuven, Belgium; KU Leuven, Dept. Neurosciences, Leuven, Belgium
| | - Olaf Riess
- Institute of Medical Genetics and Applied Genomics, University of Tuebingen, Tuebingen, Germany; Centre for Rare Diseases (ZSE), University of Tuebingen, Tuebingen, Germany
| | - Antonio Pisani
- Laboratory of Neurophysiology and Plasticity, IRCCS Fondazione Santa Lucia, Rome, Italy; Department of Systems Medicine, University of Rome Tor Vergata,Rome, Italy
| | - Kathrin Grundmann-Hauser
- Institute of Medical Genetics and Applied Genomics, University of Tuebingen, Tuebingen, Germany; Centre for Rare Diseases (ZSE), University of Tuebingen, Tuebingen, Germany
| | - Huu Phuc Nguyen
- Institute of Medical Genetics and Applied Genomics, University of Tuebingen, Tuebingen, Germany; Department of Human Genetics, Faculty of Medicine, Ruhr University Bochum, Bochum, Germany.
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Expression of the Cerebral Olfactory Receptors Olfr110/111 and Olfr544 Is Altered During Aging and in Alzheimer’s Disease-Like Mice. Mol Neurobiol 2018; 56:2057-2072. [DOI: 10.1007/s12035-018-1196-4] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2018] [Accepted: 06/26/2018] [Indexed: 01/06/2023]
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Reappraising striatal D1- and D2-neurons in reward and aversion. Neurosci Biobehav Rev 2016; 68:370-386. [PMID: 27235078 DOI: 10.1016/j.neubiorev.2016.05.021] [Citation(s) in RCA: 112] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2016] [Revised: 05/16/2016] [Accepted: 05/22/2016] [Indexed: 12/31/2022]
Abstract
The striatum has been involved in complex behaviors such as motor control, learning, decision-making, reward and aversion. The striatum is mainly composed of medium spiny neurons (MSNs), typically divided into those expressing dopamine receptor D1, forming the so-called direct pathway, and those expressing D2 receptor (indirect pathway). For decades it has been proposed that these two populations exhibit opposing control over motor output, and recently, the same dichotomy has been proposed for valenced behaviors. Whereas D1-MSNs mediate reinforcement and reward, D2-MSNs have been associated with punishment and aversion. In this review we will discuss pharmacological, genetic and optogenetic studies that indicate that there is still controversy to what concerns the role of striatal D1- and D2-MSNs in this type of behaviors, highlighting the need to reconsider the early view that they mediate solely opposing aspects of valenced behaviour.
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Chiken S, Sato A, Ohta C, Kurokawa M, Arai S, Maeshima J, Sunayama-Morita T, Sasaoka T, Nambu A. Dopamine D1 Receptor-Mediated Transmission Maintains Information Flow Through the Cortico-Striato-Entopeduncular Direct Pathway to Release Movements. Cereb Cortex 2015; 25:4885-97. [PMID: 26443442 PMCID: PMC4635926 DOI: 10.1093/cercor/bhv209] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
In the basal ganglia (BG), dopamine plays a pivotal role in motor control, and dopamine deficiency results in severe motor dysfunctions as seen in Parkinson's disease. According to the well-accepted model of the BG, dopamine activates striatal direct pathway neurons that directly project to the output nuclei of the BG through D1 receptors (D1Rs), whereas dopamine inhibits striatal indirect pathway neurons that project to the external pallidum (GPe) through D2 receptors. To clarify the exact role of dopaminergic transmission via D1Rs in vivo, we developed novel D1R knockdown mice in which D1Rs can be conditionally and reversibly regulated. Suppression of D1R expression by doxycycline treatment decreased spontaneous motor activity and impaired motor ability in the mice. Neuronal activity in the entopeduncular nucleus (EPN), one of the output nuclei of the rodent BG, was recorded in awake conditions to examine the mechanism of motor deficits. Cortically evoked inhibition in the EPN mediated by the cortico-striato-EPN direct pathway was mostly lost during suppression of D1R expression, whereas spontaneous firing rates and patterns remained unchanged. On the other hand, GPe activity changed little. These results suggest that D1R-mediated dopaminergic transmission maintains the information flow through the direct pathway to appropriately release motor actions.
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Affiliation(s)
- Satomi Chiken
- Division of System Neurophysiology, National Institute for Physiological Sciences, Okazaki 444-8585, Japan School of Life Science, SOKENDAI (The Graduate University for Advanced Studies), Okazaki 444-8585, Japan
| | - Asako Sato
- Department of Laboratory Animal Science, Kitasato University School of Medicine, Sagamihara 252-0374, Japan National Institute for Basic Biology, Okazaki 444-8585, Japan
| | - Chikara Ohta
- Division of System Neurophysiology, National Institute for Physiological Sciences, Okazaki 444-8585, Japan Department of Biological Sciences, Tokyo Metropolitan University, Tokyo 192-0397, Japan
| | - Makoto Kurokawa
- Department of Biological Sciences, Tokyo Metropolitan University, Tokyo 192-0397, Japan
| | - Satoshi Arai
- Department of Laboratory Animal Science, Kitasato University School of Medicine, Sagamihara 252-0374, Japan
| | - Jun Maeshima
- Department of Laboratory Animal Science, Kitasato University School of Medicine, Sagamihara 252-0374, Japan
| | - Tomoko Sunayama-Morita
- National Institute for Basic Biology, Okazaki 444-8585, Japan Department of Life Sciences, Graduate School of Arts and Science, The University of Tokyo, Tokyo 153-8902, Japan
| | - Toshikuni Sasaoka
- School of Life Science, SOKENDAI (The Graduate University for Advanced Studies), Okazaki 444-8585, Japan Department of Laboratory Animal Science, Kitasato University School of Medicine, Sagamihara 252-0374, Japan National Institute for Basic Biology, Okazaki 444-8585, Japan Department of Comparative and Experimental Medicine, Brain Research Institute, Niigata University, Niigata 951-8585, Japan
| | - Atsushi Nambu
- Division of System Neurophysiology, National Institute for Physiological Sciences, Okazaki 444-8585, Japan School of Life Science, SOKENDAI (The Graduate University for Advanced Studies), Okazaki 444-8585, Japan
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Pronin A, Levay K, Velmeshev D, Faghihi M, Shestopalov VI, Slepak VZ. Expression of olfactory signaling genes in the eye. PLoS One 2014; 9:e96435. [PMID: 24789354 PMCID: PMC4005753 DOI: 10.1371/journal.pone.0096435] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2014] [Accepted: 04/06/2014] [Indexed: 01/27/2023] Open
Abstract
Purpose To advance our understanding how the outer eye interacts with its environment, we asked which cellular receptors are expressed in the cornea, focusing on G protein-coupled receptors. Methods Total RNA from the mouse cornea was subjected to next-generation sequencing using the Illumina platform. The data was analyzed with TopHat and CuffLinks software packages. Expression of a representative group of genes detected by RNA-seq was further analyzed by RT-PCR and in situ hybridization using RNAscope technology and fluorescent microscopy. Results We generated more than 46 million pair-end reads from mouse corneal RNA. Bioinformatics analysis revealed that the mouse corneal transcriptome reconstructed from these reads represents over 10,000 gene transcripts. We identified 194 GPCR transcripts, of which 96 were putative olfactory receptors. RT-PCR analysis confirmed the presence of several olfactory receptors and related genes, including olfactory marker protein and the G protein associated with olfaction, Gαolf. In situ hybridization showed that mRNA for olfactory marker protein, Gαolf and possibly some olfactory receptors were found in the corneal epithelial cells. In addition to the corneal epithelium, Gαolf was present in the ganglionic and inner nuclear layers of the retina. One of the olfactory receptors, Olfr558, was present primarily in vessels of the eye co-stained with antibodies against alpha-smooth muscle actin, indicating expression in arterioles. Conclusions Several species of mRNA encoding putative olfactory receptors and related genes are expressed in the mouse cornea and other parts of the eye indicating they may play a role in sensing chemicals in the ocular environment.
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Affiliation(s)
- Alexey Pronin
- Department of Molecular and Cellular Pharmacology, University of Miami School of Medicine, Miami, Florida, United States of America
- Bascom Palmer Eye Institute, University of Miami School of Medicine, Miami, Florida, United States of America
- * E-mail: (AP); (VZS)
| | - Konstantin Levay
- Department of Molecular and Cellular Pharmacology, University of Miami School of Medicine, Miami, Florida, United States of America
| | - Dmitry Velmeshev
- Department of Psychiatry & Behavioral Sciences, University of Miami School of Medicine, Miami, Florida, United States of America
| | - Mohammad Faghihi
- Department of Psychiatry & Behavioral Sciences, University of Miami School of Medicine, Miami, Florida, United States of America
| | - Valery I. Shestopalov
- Bascom Palmer Eye Institute, University of Miami School of Medicine, Miami, Florida, United States of America
| | - Vladlen Z. Slepak
- Department of Molecular and Cellular Pharmacology, University of Miami School of Medicine, Miami, Florida, United States of America
- * E-mail: (AP); (VZS)
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Thomas RB, Joy S, Ajayan MS, Paulose CS. Neuroprotective potential of Bacopa monnieri and Bacoside A against dopamine receptor dysfunction in the cerebral cortex of neonatal hypoglycaemic rats. Cell Mol Neurobiol 2013; 33:1065-74. [PMID: 23975094 DOI: 10.1007/s10571-013-9973-0] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2013] [Accepted: 08/09/2013] [Indexed: 11/27/2022]
Abstract
Neonatal hypoglycaemia initiates a series of events leading to neuronal death, even if glucose and glycogen stores return to normal. Disturbances in the cortical dopaminergic function affect memory and cognition. We recommend Bacopa monnieri extract or Bacoside A to treat neonatal hypoglycaemia. We investigated the alterations in dopaminergic functions by studying the Dopamine D1 and D2 receptor subtypes. Receptor-binding studies revealed a significant decrease (p < 0.001) in dopamine D1 receptor number in the hypoglycaemic condition, suggesting cognitive dysfunction. cAMP content was significantly (p < 0.001) downregulated in hypoglycaemic neonatal rats indicating the reduction in cell signalling of the dopamine D1 receptors. It is attributed to the deficits in spatial learning and memory. Hypoglycaemic neonatal rats treated with Bacopa extract alone and Bacoside A ameliorated the dopaminergic and cAMP imbalance as effectively as the glucose therapy. The upregulated Bax expression in the present study indicates the high cell death in hypoglycaemic neonatal rats. Enzyme assay of SOD confirmed cortical cell death due to free radical accumulation. The gene expression of SOD in the cortex was significantly downregulated (p < 0.001). Bacopa treatment showed a significant reversal in the altered gene expression parameters (p < 0.001) of Bax and SOD. Our results suggest that in the rat experimental model of neonatal hypoglycaemia, Bacopa extract improved alterations in D1, D2 receptor expression, cAMP signalling and cell death resulting from oxidative stress. This is an important area of study given the significant motor and cognitive impairment that may arise from neonatal hypoglycaemia if proper treatment is not implemented.
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Affiliation(s)
- Roshni Baby Thomas
- Molecular Neurobiology and Cell Biology Unit, Centre for Neuroscience, Department of Biotechnology, Cochin University of Science and Technology, Cochin, 682022, Kerala, India
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Functional genomics reveals dysregulation of cortical olfactory receptors in Parkinson disease: novel putative chemoreceptors in the human brain. J Neuropathol Exp Neurol 2013; 72:524-39. [PMID: 23656994 DOI: 10.1097/nen.0b013e318294fd76] [Citation(s) in RCA: 90] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
Parkinson disease (PD) is no longer considered a complex motor disorder but rather a systemic disease with variable nonmotor deficits that may include impaired olfaction, depression, mood and sleep disorders, and altered cortical function. Increasing evidence indicates that multiple metabolic defects occur in regions outside the substantia nigra, including the cerebral cortex, even at premotor stages of the disease. We investigated changes in gene expression in the frontal cortex in PD patient brains using a transcriptomics approach. Functional genomics analysis indicated that cortical olfactory receptors (ORs) and taste receptors (TASRs) are altered in PD patients. Olfactory receptors OR2L13, OR1E1, OR2J3, OR52L1, and OR11H1 and taste receptors TAS2R5 and TAS2R50 were downregulated, but TAS2R10 and TAS2R13 were upregulated at premotor and parkinsonian stages in the frontal cortex area 8 in PD patient brains. Furthermore, we present novel evidence that, in addition to the ORs, obligate downstream components of OR function adenylyl cyclase 3 and olfactory G protein (Gαolf), OR transporters, receptor transporter proteins 1 and 2 and receptor expression enhancing protein 1, and OR xenobiotic removing UDP-glucuronosyltransferase 1 family polypeptide A6 are widely expressed in neurons of the cerebral cortex and other regions of the adult human brain. Together, these findings support the concept that ORs and TASRs in the cerebral cortex may have novel physiologic functions that are affected in PD patients.
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Wanjerkhede SM, Bapi RS. Role of CAMKII in reinforcement learning: a computational model of glutamate and dopamine signaling pathways. BIOLOGICAL CYBERNETICS 2011; 104:397-424. [PMID: 21701878 DOI: 10.1007/s00422-011-0439-5] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/01/2011] [Accepted: 05/30/2011] [Indexed: 05/31/2023]
Abstract
Timely release of dopamine (DA) at the striatum seems to be important for reinforcement learning (RL) mediated by the basal ganglia. Houk et al. (in: Houk et al (eds) Models of information processing in the basal ganglia, (1995) proposed a cellular signaling pathway model to characterize the interaction between DA and glutamate pathways that have a role in RL. The model simulation results, using GENESIS KINETIKIT simulator, point out that there is not only prolongation of duration as proposed by Houk et al. (1995), but also an enhancement in the amplitude of autophosphorylation of CaMKII. Further, the autophosphorylated form of CaMKII may form a basis for the "eligibility trace" condition required in RL. This simulation study is the first of its kind to support the comprehensive theoretical proposal of Houk et al. (1995).
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Affiliation(s)
- Shesharao M Wanjerkhede
- Department of Computer Science, Guru Nanak Dev Engineering College, Bidar, Karanataka, India.
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Tsui A, Isacson O. Functions of the nigrostriatal dopaminergic synapse and the use of neurotransplantation in Parkinson's disease. J Neurol 2011; 258:1393-405. [PMID: 21544566 DOI: 10.1007/s00415-011-6061-6] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2011] [Revised: 04/12/2011] [Accepted: 04/14/2011] [Indexed: 10/18/2022]
Abstract
While pharmaceutical options remain the overwhelmingly accepted treatment of choice for neurological and psychiatric diseases, significant accomplishments in regenerative neuroscience research have demonstrated the potential of cellular and synaptic functional repair in future therapies. Parkinson's disease stands out as an example in which repair by dopaminergic neurons appears a viable potential therapy. This article describes the basic neurobiological underpinnings of the rationale for cell therapy for Parkinson's disease and the challenges ahead for the use of regenerative medicine in the treatment for this disease.
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Affiliation(s)
- Alex Tsui
- University of Oxford Medical School, John Radcliffe Hospital, Oxford, UK.
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Surmeier DJ, Shen W, Day M, Gertler T, Chan S, Tian X, Plotkin JL. The role of dopamine in modulating the structure and function of striatal circuits. PROGRESS IN BRAIN RESEARCH 2010; 183:149-67. [PMID: 20696319 DOI: 10.1016/s0079-6123(10)83008-0] [Citation(s) in RCA: 55] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
Dopamine (DA) is a key regulator of action selection and associative learning. The striatum has long been thought to be a major locus of DA action in this process. Although all striatal cell types express G protein-coupled receptors for DA, the effects of DA on principal medium spiny neurons (MSNs) understandably have received the most attention. In the two principal classes of MSN, DA receptor expression diverges, with striatonigral MSNs robustly expressing D(1) receptors and striatopallidal MSNs expressing D(2) receptors. In the last couple of years, our understanding of how these receptors and the intracellular signalling cascades that they couple to modulate dendritic physiology and synaptic plasticity has rapidly expanded, fuelled in large measure by the development of new optical and genetic tools. These tools also have enabled a rapid expansion of our understanding of the striatal adaptations in models of Parkinson's disease. This chapter highlights some of the major advances in these areas.
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Affiliation(s)
- D James Surmeier
- Department of Physiology, Feinberg School of Medicine, Northwestern University, Chicago, IL, USA.
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D1 and D2 Dopamine Receptor Modulation of Glutamatergic Signaling in Striatal Medium Spiny Neurons. ACTA ACUST UNITED AC 2010. [DOI: 10.1016/b978-0-12-374767-9.00006-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register]
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Bettini E, Margolis FL. Expression of an intron-containing beta-tubulin mRNA in catfish olfactory epithelium. J Mol Histol 2007; 38:571-9. [PMID: 17849223 DOI: 10.1007/s10735-007-9139-9] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2007] [Accepted: 08/22/2007] [Indexed: 01/05/2023]
Abstract
Beta-tubulin genes code for very similar proteins, sharing extensive identity in amino acid sequence within and across species, each of which manifests characteristic patterns of cell and tissue expression. While searching for olfactory specific mRNAs in the channel catfish (Ictalurus punctatus), we isolated a novel beta-tubulin cDNA. In the putative ORF, 1298 nucleotides were 80-88% identical to cloned cDNAs from zebrafish to human for beta-tubulin isotype IVb. This ORF is interrupted by an insert of 111 nucleotides located between the regions corresponding to exons 2 and 3 in other species. This insert lacks similarity to any sequence in the NCBI databases. We showed that this novel cDNA fragment hybridizes specifically to catfish olfactory epithelium mRNA on Northern analysis. Here we demonstrate by in situ analysis of catfish olfactory epithelium that the expression of this mRNA is spatially restricted to the outer two-thirds of each olfactory lamella where olfactory receptor neurons reside. These results suggest that this nucleotide sequence is the result of incomplete RNA transcript processing. The growing awareness of the regulatory roles played by RNAs transcribed from intronic regions of genes suggests that this observation may have relevance to regulation of gene expression in olfactory tissue during development and axon targeting.
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Affiliation(s)
- Ezio Bettini
- Department of Anatomy and Neurobiology, School of Medicine, University of Maryland, HSF 2, Baltimore, MD 21210, USA
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Surmeier DJ, Ding J, Day M, Wang Z, Shen W. D1 and D2 dopamine-receptor modulation of striatal glutamatergic signaling in striatal medium spiny neurons. Trends Neurosci 2007; 30:228-35. [PMID: 17408758 DOI: 10.1016/j.tins.2007.03.008] [Citation(s) in RCA: 809] [Impact Index Per Article: 47.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2007] [Revised: 03/02/2007] [Accepted: 03/20/2007] [Indexed: 11/30/2022]
Abstract
Dopamine shapes a wide variety of psychomotor functions. This is mainly accomplished by modulating cortical and thalamic glutamatergic signals impinging upon principal medium spiny neurons (MSNs) of the striatum. Several lines of evidence suggest that dopamine D1 receptor signaling enhances dendritic excitability and glutamatergic signaling in striatonigral MSNs, whereas D2 receptor signaling exerts the opposite effect in striatopallidal MSNs. The functional antagonism between these two major striatal dopamine receptors extends to the regulation of synaptic plasticity. Recent studies, using transgenic mice in which cells express D1 and D2 receptors, have uncovered unappreciated differences between MSNs that shape glutamatergic signaling and the influence of DA on synaptic plasticity. These studies have also shown that long-term alterations in dopamine signaling produce profound and cell-type-specific reshaping of corticostriatal connectivity and function.
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Affiliation(s)
- D James Surmeier
- Department of Physiology, Feinberg School of Medicine, Northwestern University, Chicago, IL 60611, USA.
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Corradi JP, Ravyn V, Robbins AK, Hagan KW, Peters MF, Bostwick R, Buono RJ, Berrettini WH, Furlong ST. Alternative transcripts and evidence of imprinting of GNAL on 18p11.2. Mol Psychiatry 2005; 10:1017-25. [PMID: 16044173 DOI: 10.1038/sj.mp.4001713] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Genetic studies implicating the region of human chromosome 18p11.2 in susceptibility to bipolar disorder and schizophrenia have observed parent-of-origin effects that may be explained by genomic imprinting. We have identified a transcriptional variant of the GNAL gene in this region, employing an alternative first exon that is 5' to the originally identified start site. This alternative GNAL transcript encodes a longer functional variant of the stimulatory G-protein alpha subunit, Golf. The isoforms of Golf display different expression patterns in the CNS and functionally couple to the dopamine D1 receptor when heterologously expressed in Sf9 cells. In addition, there are CpG islands in the vicinity of both first exons that are differentially methylated, a hallmark of genomic imprinting. These results suggest that GNAL, and possibly other genes in the region, is subject to epigenetic regulation and strengthen the case for a susceptibility gene in this region.
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Affiliation(s)
- J P Corradi
- Department of Target Biology, AstraZeneca Pharmaceuticals, Wilmington, DE, USA
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Abstract
The G-protein-mediated signaling system has evolved as one of the most widely used transmembrane signaling mechanisms in eukaryotic organisms. Mammalian cells express many G-protein-coupled receptors as well as several types of heterotrimeric G-proteins and effectors. This review focuses on recent data from studies in mutant mice, which have elucidated some of the roles of G-protein-mediated signaling in physiology and pathophysiology.
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Affiliation(s)
- Nina Wettschureck
- Institute of Pharmacology, University of Heidelberg, Im Neuenheimer Feld 366, 69120, Heidelberg, Germany.
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Offermanns S. G-proteins as transducers in transmembrane signalling. PROGRESS IN BIOPHYSICS AND MOLECULAR BIOLOGY 2003; 83:101-30. [PMID: 12865075 DOI: 10.1016/s0079-6107(03)00052-x] [Citation(s) in RCA: 196] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
The G-protein-mediated signalling system has evolved as one of the most widely used transmembrane signalling mechanisms in mammalian organisms. All mammalian cells express G-protein-coupled receptors as well as several types of heterotrimeric G-proteins and effectors. G-protein-mediated signalling is involved in many physiological and pathological processes. This review summarizes some general aspects of G-protein-mediated signalling and focusses on recent data especially from studies in mutant mice which have elucidated some of the cellular and biological functions of heterotrimeric G-prtoteins.
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Affiliation(s)
- Stefan Offermanns
- Institute of Pharmacology, University of Heidelberg, Im Neuenheimer Feld 366, 69120 Heidelberg, Germany.
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Dopamine-dependent desensitization of dopaminergic signaling in the developing mouse striatum. J Neurosci 2002. [PMID: 12427840 DOI: 10.1523/jneurosci.22-22-09841.2002] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
The dynamics of dopamine receptor signaling efficacy were characterized in developing mice by measuring striatal c-Fos expression after dopaminergic agonist treatment at postnatal day 4 (P4) to P18. Control mice and mutant mice, in which dopamine production is inactivated in dopaminergic neurons by gene targeting, were treated with saline; a synthetic dopamine precursor, L-3,4-dihydroxyphenylalanine (L-DOPA) methyl ester; a direct dopamine D(1) receptor agonist, N-allyl-SKF 38393; or a dopamine reuptake inhibitor, cocaine. L-DOPA methyl ester treatment failed to induce striatal c-Fos immunoreactivity in control and mutant mice deficient in dopamine production at P4 and P6 compared with saline treatment. However, at P10 through P18 it induced abundant c-Fos expression in mutants. At these later stages, c-Fos expression remained at basal levels in control mice after L-DOPA methyl ester treatment. Control and mutant mice responded to D1 receptor agonist administration to a similar degree at P4 and P6, but the responses were greatly enhanced in mutants at later stages. Cocaine treatment elicited expression in control mice at P10 through P18 but not at P4 and P6. Mutant mice were largely unresponsive to cocaine treatment. The results suggest that striatal dopamine receptors are capable of transducing extracellular signals at P4 and P6, but dopaminergic neurotransmission begins thereafter. Dopaminoceptive neurons appear to reduce their sensitivity to dopamine as dopaminergic terminals innervate the striatum and functional neurotransmission begins.
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Martin G, Fabre V, Siggins GR, de Lecea L. Interaction of the hypocretins with neurotransmitters in the nucleus accumbens. REGULATORY PEPTIDES 2002; 104:111-7. [PMID: 11830285 DOI: 10.1016/s0167-0115(01)00354-8] [Citation(s) in RCA: 75] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
The hypocretins (hcrt1 and hcrt2), also known as orexins, are two neuropeptides derived from the same precursor, expressed in a few thousand cells in the lateral hypothalamus. Hypocretin-containing cells project throughout the brain, including ascending projections to the olfactory bulb and cerebral cortex, through the medial septum and the nucleus accumbens. Here, we have studied the interactions of the hypocretins with different neurotransmitters by patch clamp recording of acutely dissociated cells from the nucleus accumbens. Application of hcrt1 or hcrt2 decreased postsynaptic NMDA currents, enhanced GABA currents but did not affect glycine-activated conductances. Our results strongly suggest that the hypocretin peptides may be inhibitory peptides, probably via binding hcrt receptor 2.
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Affiliation(s)
- Gilles Martin
- Department of Neuropharmacology, The Scripps Research Institute, La Jolla, CA 92037, USA
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Galpha(olf) levels are regulated by receptor usage and control dopamine and adenosine action in the striatum. J Neurosci 2001. [PMID: 11404425 DOI: 10.1523/jneurosci.21-12-04390.2001] [Citation(s) in RCA: 106] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
In the striatum, dopamine D(1) and adenosine A(2A) receptors stimulate the production of cAMP, which is involved in neuromodulation and long-lasting changes in gene expression and synaptic function. Positive coupling of receptors to adenylyl cyclase can be mediated through the ubiquitous GTP-binding protein Galpha(S) subunit or through the olfactory isoform, Galpha(olf), which predominates in the striatum. In this study, using double in situ hybridization, we show that virtually all striatal efferent neurons, identified by the expression of preproenkephalin A, substance P, or D(1) receptor mRNA, contained high amounts of Galpha(olf) mRNA and undetectable levels of Galpha(s) mRNA. In contrast, the large cholinergic interneurons contained both Galpha(olf) and Galpha(s) transcripts. To assess the functional relationship between dopamine or adenosine receptors and G-proteins, we examined G-protein levels in the striatum of D(1) and A(2A) receptor knock-out mice. A selective increase in Galpha(olf) protein was observed in these animals, without change in mRNA levels. Conversely, Galpha(olf) levels were decreased in animals lacking a functional dopamine transporter. These results indicate that Galpha(olf) protein levels are regulated through D(1) and A(2A) receptor usage. To determine the functional consequences of changes in Galpha(olf) levels, we used heterozygous Galpha(olf) knock-out mice, which possess half of the normal Galpha(olf) levels. In these animals, the locomotor effects of amphetamine and caffeine, two psychostimulant drugs that affect dopamine and adenosine signaling, respectively, were markedly reduced. Together, these results identify Galpha(olf) as a critical and regulated component of both dopamine and adenosine signaling.
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Abstract
Heterotrimeric guanine nucleotide binding proteins (G-proteins) mediate the effects of numerous hormones, neurotransmitters or sensory stimuli by coupling their transmembranous receptors to various effectors like enzymes and ion channels. Changes in the activity of these effector molecules eventually lead to the regulation of multiple cellular functions ranging from short term regulatory processes like the control of secretion rates, muscle tonus or metabolic processes to long term effects like regulation of growth and differentiation. Heterotrimeric G-proteins play a pivotal role in this transmembrane signaling process as they take part in processing and sorting of incoming signals as well as in adjusting the sensitivity of the system. This review describes some of the new insights into the biological role of G-protein mediated signaling processes provided by the analysis of mice genetically engineered to lack distinct G-protein alpha-subunits.
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Affiliation(s)
- S Offermanns
- Pharmakologisches Institut, Universität Heidelberg, Im Neuenheimer Feld 366, 69120 Heidelberg, Germany
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25
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Vuoristo JT, Berrettini WH, Overhauser J, Prockop DJ, Ferraro TN, Ala-Kokko L. Sequence and genomic organization of the human G-protein Golfalpha gene (GNAL) on chromosome 18p11, a susceptibility region for bipolar disorder and schizophrenia. Mol Psychiatry 2000; 5:495-501. [PMID: 11032382 DOI: 10.1038/sj.mp.4000758] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
The sequence and genomic organization of the human Golfalpha (GNAL) gene were determined. The human GNAL gene was found to contain 12 coding exons, and it spans over 80 kb on chromosome 18p11. 5' RACE analysis suggested an additional transcription initiation start site. Sequence analysis of the putative promoter region revealed conserved binding sites for several transcription factors. Sequence analysis of the 3'-untranslated region revealed the presence of two Alu sequences and two polyadenylation signals. 3' RACE analysis confirmed the functionality of the most downstream poly-a signal. The human GNAL was found to be expressed as a single transcript of about 5.9 kb in the brain. One highly informative dinucleotide repeat was found in intron 5. Additionally, a processed pseudogene for asparagine synthetase was found about 6 kb upstream of the GNAL gene. Knowledge of the sequence and structure of the human GNAL gene provides essential information for further analysis of the GNAL locus at chromosome 18p11 which has been linked to bipolar disorder and schizophrenia.
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Affiliation(s)
- J T Vuoristo
- Biocenter Oulu and Department of Medical Biochemistry, University of Oulu, Finland
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26
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Offermanns S. Mammalian G-protein function in vivo: new insights through altered gene expression. Rev Physiol Biochem Pharmacol 2000; 140:63-133. [PMID: 10857398 DOI: 10.1007/bfb0035551] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Affiliation(s)
- S Offermanns
- Institut für Pharmakologie, Universitätsklinikum Benjamin Franklin, Freie Universität Berlin, Germany
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Beaudoing E, Freier S, Wyatt JR, Claverie JM, Gautheret D. Patterns of variant polyadenylation signal usage in human genes. Genome Res 2000; 10:1001-10. [PMID: 10899149 PMCID: PMC310884 DOI: 10.1101/gr.10.7.1001] [Citation(s) in RCA: 494] [Impact Index Per Article: 20.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/14/2022]
Abstract
The formation of mature mRNAs in vertebrates involves the cleavage and polyadenylation of the pre-mRNA, 10-30 nt downstream of an AAUAAA or AUUAAA signal sequence. The extensive cDNA data now available shows that these hexamers are not strictly conserved. In order to identify variant polyadenylation signals on a large scale, we compared over 8700 human 3' untranslated sequences to 157,775 polyadenylated expressed sequence tags (ESTs), used as markers of actual mRNA 3' ends. About 5600 EST-supported putative mRNA 3' ends were collected and analyzed for significant hexameric sequences. Known polyadenylation signals were found in only 73% of the 3' fragments. Ten single-base variants of the AAUAAA sequence were identified with a highly significant occurrence rate, potentially representing 14.9% of the actual polyadenylation signals. Of the mRNAs, 28.6% displayed two or more polyadenylation sites. In these mRNAs, the poly(A) sites proximal to the coding sequence tend to use variant signals more often, while the 3'-most site tends to use a canonical signal. The average number of ESTs associated with each signal type suggests that variant signals (including the common AUUAAA) are processed less efficiently than the canonical signal and could therefore be selected for regulatory purposes. However, the position of the site in the untranslated region may also play a role in polyadenylation rate.
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Affiliation(s)
- E Beaudoing
- Structural and Genetic Information Laboratory, Marseille, France
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28
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Phan HH, Boissard C, Pessah M, Regnauld K, Emami S, Gespach C, Rosselin G. Decreased ADP-ribosylation of the Galpha(olf) and Galpha(s) subunits by high glucose in pancreatic B-cells. Biochem Biophys Res Commun 2000; 271:86-90. [PMID: 10777686 DOI: 10.1006/bbrc.2000.2580] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
In HIT-T15 insulinoma B-cells incubated in presence of [(32)P]NAD, we identified by autoradiography and immunoblotting ADP-ribosylation (ADP-R) of the trimeric G-protein Galpha(s) and Galpha(olf) subunits (45 kDa) induced by cholera toxin in M1 (120,000g) and M2 (70,000g) subcellular fractions containing plasma membranes, insulin granules, and mitochondria. This ADP-R indicates that these two fractions contain functionally competent Galpha subunits for adenylyl cyclase activation. Prolonged exposure of HIT-T15 cells to high glucose (25 mM instead of 6 mM) specifically reduced the ADP-R in Galpha(s) and Galpha(olf) subunits in the M1 fraction only, despite the clear increase of their accumulation in this compartment. A similar alteration in the ADP-R of the M1-associated Galpha(s) and Galpha(olf) subunits was observed in pancreatic islets isolated from fasted and fed rats. These results may explain, at least in part, the undesirable effects of sustained hyperglycemia on the cAMP-dependent process of insulin secretion in diabetes.
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Affiliation(s)
- H H Phan
- Laboratoire de Signalisation et Fonctions Cellulaires, Applications au Diabète et aux Cancers Digestifs, Unité INSERM 482, IFR65, Hôpital Saint-Antoine, 184 rue du Faubourg Saint-Antoine, Paris Cédex 12, 75571, France
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Caffrey JJ, Safrany ST, Yang X, Shears SB. Discovery of molecular and catalytic diversity among human diphosphoinositol-polyphosphate phosphohydrolases. An expanding Nudt family. J Biol Chem 2000; 275:12730-6. [PMID: 10777568 DOI: 10.1074/jbc.275.17.12730] [Citation(s) in RCA: 68] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
The turnover of the "high energy" diphosphoinositol polyphosphates by Ca(2+)- and cyclic nucleotide-modulated enzymes is considered a regulatory, molecular switching activity. Target processes may include intracellular trafficking. Following our earlier identification of a prototype human diphosphoinositol-polyphosphate phosphohydrolase (hDIPP1), we now describe new 21-kDa human isoforms, hDIPP2alpha and hDIPP2beta, distinguished from each other solely by hDIPP2beta possessing one additional amino acid (Gln(86)). Candidate DIPP2alpha and DIPP2beta homologues in rat and mouse were also identified. The rank order for catalytic activity is hDIPP1 > hDIPP2alpha > hDIPP2beta. Differential expression of hDIPP isoforms may provide flexibility in response times of the molecular switches. The 76% identity between hDIPP1 and the hDIPP2s includes conservation of an emerging signature sequence, namely, a Nudt (MutT) motif with a GX(2)GX(6)G carboxy extension. Northern and Western analyses indicate expression of hDIPP2s is broad but atypically controlled; these proteins are translated from multiple mRNAs that differ in the length of the 3'-untranslated region because of utilization of an array of alternative (canonical and noncanonical) polyadenylation signals. Thus, cells can recruit sophisticated molecular processes to regulate diphosphoinositol polyphosphate turnover.
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Affiliation(s)
- J J Caffrey
- Inositide Signaling Group, NIEHS, National Institutes of Health, Research Triangle Park, North Carolina 27709, USA.
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30
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Gardner HP, Wertheim GB, Ha SI, Copeland NG, Gilbert DJ, Jenkins NA, Marquis ST, Chodosh LA. Cloning and characterization of Hunk, a novel mammalian SNF1-related protein kinase. Genomics 2000; 63:46-59. [PMID: 10662544 DOI: 10.1006/geno.1999.6078] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
We previously identified a novel protein kinase, Hunk, by means of a degenerate PCR screen designed to isolate kinases expressed in the murine mammary gland. We now describe the molecular cloning, chromosomal localization, and activity of this kinase and characterize its spatial and temporal pattern of expression in the mouse. We have isolated a 5.0-kb full-length cDNA clone that contains the 714-amino-acid open reading frame encoding Hunk. Analysis of this cDNA reveals that Hunk is most closely related to the SNF1 family of serine/threonine kinases and contains a newly described SNF1 homology domain. Accordingly, antisera specific for Hunk detect an 80-kDa polypeptide with associated phosphotransferase activity. Hunk is located on distal mouse chromosome 16 in a region of conserved synteny with human chromosome 21q22. During fetal development and in the adult mouse, Hunk mRNA expression is developmentally regulated and tissue-specific. Moreover, in situ hybridization analysis reveals that Hunk expression is restricted to subsets of cells within a variety of organs in the adult mouse. These findings suggest a role for Hunk in murine development.
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Affiliation(s)
- H P Gardner
- Department of Molecular and Cellular Engineering, Division of Endocrinology, Diabetes, and Metabolism, University of Pennsylvania School of Medicine, 421 Curie Boulevard, 612 Biomedical Research Building II/III, Philadelphia, Pennsylvania, 19104-6160, USAC
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31
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Wilkinson R, Tscharke D, Simmons A. Golfalpha is expressed in primary sensory neurons outside of the olfactory neuroepithelium. Brain Res 1999; 831:311-4. [PMID: 10412013 DOI: 10.1016/s0006-8993(99)01488-2] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Golfalpha is the alpha chain of a trimolecular stimulatory G protein originally described as the G protein responsible for signal transduction in odourant recognition within neurons of the olfactory neuroepithelium. While applying the technique of mRNA differential display to herpes simplex virus infected tissue, a partial cDNA clone corresponding to the mouse homologue of Golfalpha was isolated from sensory dorsal root ganglia. Levels of this transcript were reduced following viral infection and this reduction was enhanced in CD8(+) depleted mice. The presence of this G protein within sensory ganglia was confirmed with Northern blotting and PCR and in situ hybridization studies localised Golfalpha expression exclusively to neurons within this tissue.
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Affiliation(s)
- R Wilkinson
- Infectious Diseases Laboratories, Institute of Medical and Veterinary Science, Frome Road, Adelaide, South Australia 5000, Australia.
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Astesano A, Regnauld K, Ferrand N, Gingras D, Bendayan M, Rosselin G, Emami S. Cellular and subcellular expression of Golf/Gs and Gq/G11 alpha-subunits in rat pancreatic endocrine cells. J Histochem Cytochem 1999; 47:289-302. [PMID: 10026232 DOI: 10.1177/002215549904700303] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
We studied the cellular and subcellular localization of Galpha-subunits in pancreas by immunocytochemistry. Golfalpha and G11alpha were specifically localized in islet insulin B-cells and glucagon A-cells, respectively. Gsalpha and Gqalpha labeling was more abundant in B-cells. The presence of Golfalpha in B-cells was confirmed by in situ hybridization. In B-cells, Golfalpha and Gsalpha were found in the Golgi apparatus, plasma membrane (PM) and, remarkably, in mature and immature insulin secretory granules, mainly at the periphery of the insulin grains. Gqalpha was detected on the rough endoplasmic reticulum (RER) near the Golgi apparatus. In A-cells, the Galpha-subunits were mostly within the glucagon granules: G11alpha gave the strongest signal, Gsalpha less strong, Gq was scarce, and Golf was practically absent. Gqalpha and Gsalpha immunoreactivity was detected in acinar cells, although it was much weaker than that in islet cells. The cell-dependent distribution of the Galpha-subunits indicates that the stimulatory pathways for pancreatic function differ in acinar and in islet B- and A-cells. Furthermore, the G-protein subunits in islet cell secretory granules might be functional and participate in granule trafficking and hormone secretion.
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Affiliation(s)
- A Astesano
- Unité de Recherches sur la Signalisation et les Fonctions Cellulaires: Paris, France
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Frayon S, Pessah M, Giroix MH, Mercan D, Boissard C, Malaisse WJ, Portha B, Garel JM. Galphaolf identification by RT-PCR in purified normal pancreatic B cells and in islets from rat models of non-insulin-dependent diabetes. Biochem Biophys Res Commun 1999; 254:269-72. [PMID: 9920769 DOI: 10.1006/bbrc.1998.9791] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Recent reports using immunohistochemistry have shown that Galphaolf which shares 88% homology with Galphas was expressed in pancreatic islets. To test the specificity of the expression of this G protein isotype in rat islet cells, B and non-B cells were separated by flow cytometry. The expression of Galphaolf and adenylyl cyclases (AC) of types II, III, V, and VI was evaluated by reverse-transcriptase polymerase chain reaction (RT-PCR). Since alterations in the expression of AC III were recently reported in the GK rat (a model of non-insulin-dependent diabetes mellitus, NIDDM), we also have analyzed the mRNA expression of Galphaolf and AC isoforms in pancreatic islets from GK rats and from adult rats neonatally treated by streptozotocin (nSTZ rats), another model of NIDDM. Southern blots of amplicons generated with specific primers of Galphaolf revealed the presence of a 540-bp band only in B cells. AC of types II, III, V, and VI were expressed both in B and non-B cells. However, AC III mRNA was clearly more abundant in non-B than in B cells. Moreover, in B cells the expression of AC VI was higher than that of AC V, whereas equal expressions of AC V and AC VI were found in non-B cells. In GK rat islets, the mRNA expressions of Galphaolf, AC II, and AC III were clearly increased and no change in AC V and AC VI was found. In nSTZ rat islets, Galphaolf expression was barely detectable, but AC II and AC III mRNA levels were higher than those observed in controls. In conclusion, Galphaolf mRNA appeared specifically expressed in islet B cells and was increased in GK islets. The steady-state mRNA levels of AC II and AC III were clearly increased in the islets of the two rat models of NIDDM. Thus, alterations in the expression of G protein isotypes and AC isoforms could contribute to the diabetic phenotype.
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Affiliation(s)
- S Frayon
- Unité 482 de l'INSERM, Hôpital Saint-Antoine, 184 rue du Faubourg St-Antoine, Paris-Cedex 12, 75571, France
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Emami S, Regnauld K, Ferrand N, Astesano A, Pessah M, Phan H, Boissard C, Garel JM, Rosselin G. Stimulatory transducing systems in pancreatic islet cells. Ann N Y Acad Sci 1998; 865:118-31. [PMID: 9928004 DOI: 10.1111/j.1749-6632.1998.tb11170.x] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
We have determined the cellular distribution of different alpha subtypes of G proteins and adenylyl cyclase (AC) isoforms in endocrine, exocrine, and established pancreatic cell lines. VIP, PACAP, and tGLP-1 receptor proteins are expressed to varying extents in A and B cells, whereas the expression of G alpha subunits is cell specific. Thus, G(olf) alpha is detected in normal rodent B cells and immortalized pancreatic B cell lines, whereas Gs alpha is more ubiquitously expressed. The cellular density of AC isoforms labeling (I, II, III, IV, V/VI) is also islet cell-specific and their distribution is age- and species-dependent. The identification of numerous signaling molecule subtypes, together with the discovery of their specific subcellular distribution, will help the functional characterization of their intraregulatory pathways, leading to the extrusion of insulin or glucagon secretory granules, and those leading to differentiation and apoptosis of islet cells.
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Affiliation(s)
- S Emami
- Institut National de la Santé et de la Recherche Médicale, Centre de Recherche Paris Saint-Antoine, France.
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Schwab SG, Hallmayer J, Lerer B, Albus M, Borrmann M, Hönig S, Strauss M, Segman R, Lichtermann D, Knapp M, Trixler M, Maier W, Wildenauer DB. Support for a chromosome 18p locus conferring susceptibility to functional psychoses in families with schizophrenia, by association and linkage analysis. Am J Hum Genet 1998; 63:1139-52. [PMID: 9758604 PMCID: PMC1377479 DOI: 10.1086/302046] [Citation(s) in RCA: 114] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022] Open
Abstract
The action of antipsychotic drugs on dopamine receptors suggests that dopaminergic signal transmission may play a role in the development of schizophrenia. We tested eight candidate genes (coding for dopamine receptors, the dopamine transporter, and G-proteins) in 59 families from Germany and Israel, for association. A P value of .00055 (.0044 when corrected for the no. of markers tested) was obtained for the intronic CA-repeat marker G-olfalpha on chromosome 18p. The value decreased to .000088 (.0007) when nine sibs with recurrent unipolar depressive disorder were included. Linkage analysis using SSLP markers densely spaced around G-olfalpha yielded a maximum two-point LOD score of 3.1 for a marker 0.5 cM distal to G-olfalpha. Multipoint analysis under the assumption of heterogeneity supported this linkage-whether the affected pheotype was defined narrowly or broadly-as did nonparametric linkage (NPL). In 12 families with exclusively maternal transmission of the disease, the NPL value also supported linkage to this marker. In order to test for association/linkage disequilibrium in the presence of linkage, the sample was restricted to independent offspring. When this sample was combined with 65 additional simplex families (each of them comprising one schizophrenic offspring and his or her parents), the 124-bp allele of G-olfalpha was transmitted 47 times and was not transmitted 21 times (P=.009). These results suggest the existence, on chromosome 18p, of a potential susceptibility locus for functional psychoses.
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Affiliation(s)
- S G Schwab
- Molecular Genetics Laboratory, Department of Psychiatry, University of Bon, Germany
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Abstract
Considerable progress has been made in the understanding of transduction mechanisms in olfactory receptor neurons (ORNs) over the last decade. Odorants pass through a mucus interface before binding to odorant receptors (ORs). The molecular structure of many ORs is now known. They belong to the large class of G protein-coupled receptors with seven transmembrane domains. Binding of an odorant to an OR triggers the activation of second messenger cascades. One second messenger pathway in particular has been extensively studied; the receptor activates, via the G protein Golf, an adenylyl cyclase, resulting in an increase in adenosine 3',5'-cyclic monophosphate (cAMP), which elicits opening of cation channels directly gated by cAMP. Under physiological conditions, Ca2+ has the highest permeability through this channel, and the increase in intracellular Ca2+ concentration activates a Cl- current which, owing to an elevated reversal potential for Cl-, depolarizes the olfactory neuron. The receptor potential finally leads to the generation of action potentials conveying the chemosensory information to the olfactory bulb. Although much less studied, other transduction pathways appear to exist, some of which seem to involve the odorant-induced formation of inositol polyphosphates as well as Ca2+ and/or inositol polyphosphate -activated cation channels. In addition, there is evidence for odorant-modulated K+ and Cl- conductances. Finally, in some species, ORNs can be inhibited by certain odorants. This paper presents a comprehensive review of the biophysical and electrophysiological evidence regarding the transduction processes as well as subsequent signal processing and spike generation in ORNs.
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Affiliation(s)
- D Schild
- Physiologisches Institut, Universität Göttingen, Germany
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Defer N, Marinx O, Poyard M, Lienard MO, Jégou B, Hanoune J. The olfactory adenylyl cyclase type 3 is expressed in male germ cells. FEBS Lett 1998; 424:216-20. [PMID: 9539154 DOI: 10.1016/s0014-5793(98)00178-1] [Citation(s) in RCA: 48] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Elements of the olfactory pathway, such as receptors, receptor-desensitization machinery, and cyclic nucleotide-gated channels, are expressed in male germ cells. Here we report the expression, in rat testis, of both adenylyl cyclase type 3 (AC3) and the olfactory G protein subunit, G(alpha)olf. Both are expressed in the same sub-population of germ cells, pachytene spermatocytes to spermatids, and in residual bodies. Neither AC3 nor G(alpha)olf was found in Sertoli or in peritubular cells, as shown by Western blotting and immunocytochemical analyses. It thus appears that male germ cells contain all the elements of the signaling cascade present in olfactory cells.
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Affiliation(s)
- N Defer
- U-99 INSERM, Hopital Henri Mondor, Créteil, France
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Abstract
We have used gene targeting to examine the role of the G alpha subunit, G(olf), in olfactory signal transduction. Mice homozygous for a null mutation in G(olf) show a striking reduction in the electrophysiological response of primary olfactory sensory neurons to a wide variety of odors. Despite this profound diminution in response to odors, the topographic map of primary sensory projections to the olfactory bulb remains unaltered in G(olf) mutants. Greater than 75% of the G(olf) mutant mice are unable to nurse and die within 2 days after birth. Rare surviving homozygotes mate and are fertile, but mutant females exhibit inadequate maternal behaviors. Surviving homozygous mutant mice also exhibit hyperactive behaviors. These behavioral phenotypes, taken together with the patterns of G(olf) expression, suggest that G(olf) is required for olfactory signal transduction and may also function as an essential signaling molecule more centrally in the brain.
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Affiliation(s)
- L Belluscio
- Department of Biochemistry and Molecular Biophysics, College of Physicians and Surgeons, Columbia University, New York, New York 10032, USA
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