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Fazzini F, Lamina C, Raftopoulou A, Koller A, Fuchsberger C, Pattaro C, Del Greco FM, Döttelmayer P, Fendt L, Fritz J, Meiselbach H, Schönherr S, Forer L, Weissensteiner H, Pramstaller PP, Eckardt K, Hicks AA, Kronenberg F. Association of mitochondrial DNA copy number with metabolic syndrome and type 2 diabetes in 14 176 individuals. J Intern Med 2021; 290:190-202. [PMID: 33453124 PMCID: PMC8359248 DOI: 10.1111/joim.13242] [Citation(s) in RCA: 55] [Impact Index Per Article: 18.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/18/2020] [Revised: 11/24/2020] [Accepted: 12/14/2020] [Indexed: 12/14/2022]
Abstract
BACKGROUND Mitochondria play an important role in cellular metabolism, and their dysfunction is postulated to be involved in metabolic disturbances. Mitochondrial DNA is present in multiple copies per cell. The quantification of mitochondrial DNA copy number (mtDNA-CN) might be used to assess mitochondrial dysfunction. OBJECTIVES We aimed to investigate the cross-sectional association of mtDNA-CN with type 2 diabetes and the potential mediating role of metabolic syndrome. METHODS We examined 4812 patients from the German Chronic Kidney Disease (GCKD) study and 9364 individuals from the Cooperative Health Research in South Tyrol (CHRIS) study. MtDNA-CN was measured in whole blood using a plasmid-normalized qPCR-based assay. RESULTS In both studies, mtDNA-CN showed a significant correlation with most metabolic syndrome parameters: mtDNA-CN decreased with increasing number of metabolic syndrome components. Furthermore, individuals with low mtDNA-CN had significantly higher odds of metabolic syndrome (OR = 1.025; 95% CI = 1.011-1.039, P = 3.19 × 10-4 , for each decrease of 10 mtDNA copies) and type 2 diabetes (OR = 1.027; 95% CI = 1.012-1.041; P = 2.84 × 10-4 ) in a model adjusted for age, sex, smoking and kidney function in the meta-analysis of both studies. Mediation analysis revealed that the association of mtDNA-CN with type 2 diabetes was mainly mediated by waist circumference in the GCKD study (66%) and by several metabolic syndrome parameters, especially body mass index and triglycerides, in the CHRIS study (41%). CONCLUSIONS Our data show an inverse association of mtDNA-CN with higher risk of metabolic syndrome and type 2 diabetes. A major part of the total effect of mtDNA-CN on type 2 diabetes is mediated by obesity parameters.
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Affiliation(s)
- F. Fazzini
- From theDepartment of Genetics and PharmacologyInstitute of Genetic EpidemiologyMedical University of InnsbruckInnsbruckAustria
| | - C. Lamina
- From theDepartment of Genetics and PharmacologyInstitute of Genetic EpidemiologyMedical University of InnsbruckInnsbruckAustria
| | - A. Raftopoulou
- Eurac ResearchInstitute for BiomedicineAffiliated Institute of the University of LübeckBolzanoItaly
| | - A. Koller
- From theDepartment of Genetics and PharmacologyInstitute of Genetic EpidemiologyMedical University of InnsbruckInnsbruckAustria
| | - C. Fuchsberger
- Eurac ResearchInstitute for BiomedicineAffiliated Institute of the University of LübeckBolzanoItaly
| | - C. Pattaro
- Eurac ResearchInstitute for BiomedicineAffiliated Institute of the University of LübeckBolzanoItaly
| | - F. M. Del Greco
- Eurac ResearchInstitute for BiomedicineAffiliated Institute of the University of LübeckBolzanoItaly
| | - P. Döttelmayer
- From theDepartment of Genetics and PharmacologyInstitute of Genetic EpidemiologyMedical University of InnsbruckInnsbruckAustria
| | - L. Fendt
- From theDepartment of Genetics and PharmacologyInstitute of Genetic EpidemiologyMedical University of InnsbruckInnsbruckAustria
| | - J. Fritz
- Department of Medical StatisticsInformatics and Health EconomicsMedical University of InnsbruckInnsbruckAustria
- Department of Integrative PhysiologyUniversity of Colorado BoulderBoulderCOUSA
| | - H. Meiselbach
- Department of Nephrology and HypertensionFriedrich‐Alexander Universität Erlangen‐Nürnberg (FAU)ErlangenGermany
| | - S. Schönherr
- From theDepartment of Genetics and PharmacologyInstitute of Genetic EpidemiologyMedical University of InnsbruckInnsbruckAustria
| | - L. Forer
- From theDepartment of Genetics and PharmacologyInstitute of Genetic EpidemiologyMedical University of InnsbruckInnsbruckAustria
| | - H. Weissensteiner
- From theDepartment of Genetics and PharmacologyInstitute of Genetic EpidemiologyMedical University of InnsbruckInnsbruckAustria
| | - P. P. Pramstaller
- Eurac ResearchInstitute for BiomedicineAffiliated Institute of the University of LübeckBolzanoItaly
| | - K.‐U. Eckardt
- Department of Nephrology and HypertensionFriedrich‐Alexander Universität Erlangen‐Nürnberg (FAU)ErlangenGermany
- Department of Nephrology and Medical Intensive CareCharité – Universitätsmedizin BerlinBerlinGermany
| | - A. A. Hicks
- Eurac ResearchInstitute for BiomedicineAffiliated Institute of the University of LübeckBolzanoItaly
| | - F. Kronenberg
- From theDepartment of Genetics and PharmacologyInstitute of Genetic EpidemiologyMedical University of InnsbruckInnsbruckAustria
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Peronio P, Labanca I, Acconcia G, Ruggeri A, Lavdas AA, Hicks AA, Pramstaller PP, Ghioni M, Rech I. 32-channel time-correlated-single-photon-counting system for high-throughput lifetime imaging. Rev Sci Instrum 2017; 88:083704. [PMID: 28863689 DOI: 10.1063/1.4986049] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/10/2023]
Abstract
Time-Correlated Single Photon Counting (TCSPC) is a very efficient technique for measuring weak and fast optical signals, but it is mainly limited by the relatively "long" measurement time. Multichannel systems have been developed in recent years aiming to overcome this limitation by managing several detectors or TCSPC devices in parallel. Nevertheless, if we look at state-of-the-art systems, there is still a strong trade-off between the parallelism level and performance: the higher the number of channels, the poorer the performance. In 2013, we presented a complete and compact 32 × 1 TCSPC system, composed of an array of 32 single-photon avalanche diodes connected to 32 time-to-amplitude converters, which showed that it was possible to overcome the existing trade-off. In this paper, we present an evolution of the previous work that is conceived for high-throughput fluorescence lifetime imaging microscopy. This application can be addressed by the new system thanks to a centralized logic, fast data management and an interface to a microscope. The new conceived hardware structure is presented, as well as the firmware developed to manage the operation of the module. Finally, preliminary results, obtained from the practical application of the technology, are shown to validate the developed system.
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Affiliation(s)
- P Peronio
- Dipartimento di Elettronica, Informazione e Bioingegneria, Politecnico di Milano, Piazza Leonardo da Vinci 32, 20133 Milano, Italy
| | - I Labanca
- Dipartimento di Elettronica, Informazione e Bioingegneria, Politecnico di Milano, Piazza Leonardo da Vinci 32, 20133 Milano, Italy
| | - G Acconcia
- Dipartimento di Elettronica, Informazione e Bioingegneria, Politecnico di Milano, Piazza Leonardo da Vinci 32, 20133 Milano, Italy
| | - A Ruggeri
- Micro Photon Devices S.R.L., via Stradivari 4, 39100 Bolzano, Italy
| | - A A Lavdas
- Institute for Biomedicine, Eurac Research, Affiliated Institute of the University of Lübeck, via Galvani 31, 39100 Bolzano, Italy
| | - A A Hicks
- Institute for Biomedicine, Eurac Research, Affiliated Institute of the University of Lübeck, via Galvani 31, 39100 Bolzano, Italy
| | - P P Pramstaller
- Institute for Biomedicine, Eurac Research, Affiliated Institute of the University of Lübeck, via Galvani 31, 39100 Bolzano, Italy
| | - M Ghioni
- Dipartimento di Elettronica, Informazione e Bioingegneria, Politecnico di Milano, Piazza Leonardo da Vinci 32, 20133 Milano, Italy
| | - I Rech
- Dipartimento di Elettronica, Informazione e Bioingegneria, Politecnico di Milano, Piazza Leonardo da Vinci 32, 20133 Milano, Italy
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Allebrandt KV, Amin N, Müller-Myhsok B, Esko T, Teder-Laving M, Azevedo RVDM, Hayward C, van Mill J, Vogelzangs N, Green EW, Melville SA, Lichtner P, Wichmann HE, Oostra BA, Janssens ACJW, Campbell H, Wilson JF, Hicks AA, Pramstaller PP, Dogas Z, Rudan I, Merrow M, Penninx B, Kyriacou CP, Metspalu A, van Duijn CM, Meitinger T, Roenneberg T. A K(ATP) channel gene effect on sleep duration: from genome-wide association studies to function in Drosophila. Mol Psychiatry 2013; 18:122-32. [PMID: 22105623 DOI: 10.1038/mp.2011.142] [Citation(s) in RCA: 116] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/25/2011] [Revised: 09/01/2011] [Accepted: 09/27/2011] [Indexed: 11/08/2022]
Abstract
Humans sleep approximately a third of their lifetime. The observation that individuals with either long or short sleep duration show associations with metabolic syndrome and psychiatric disorders suggests that the length of sleep is adaptive. Although sleep duration can be influenced by photoperiod (season) and phase of entrainment (chronotype), human familial sleep disorders indicate that there is a strong genetic modulation of sleep. Therefore, we conducted high-density genome-wide association studies for sleep duration in seven European populations (N=4251). We identified an intronic variant (rs11046205; P=3.99 × 10(-8)) in the ABCC9 gene that explains ≈5% of the variation in sleep duration. An influence of season and chronotype on sleep duration was solely observed in the replication sample (N=5949). Meta-analysis of the associations found in a subgroup of the replication sample, chosen for season of entry and chronotype, together with the discovery results showed genome-wide significance. RNA interference knockdown experiments of the conserved ABCC9 homologue in Drosophila neurons renders flies sleepless during the first 3 h of the night. ABCC9 encodes an ATP-sensitive potassium channel subunit (SUR2), serving as a sensor of intracellular energy metabolism.
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Affiliation(s)
- K V Allebrandt
- Institute of Medical Psychology, Ludwig-Maximilians-University, Munich, Germany
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Sveinbjörnsdottir S, Hicks AA, Jonsson T, Pétursson H, Guğmundsson G, Frigge ML, Kong A, Gulcher JR, Stefansson K. Familial aggregation of Parkinson's disease in Iceland. N Engl J Med 2000; 343:1765-70. [PMID: 11114315 DOI: 10.1056/nejm200012143432404] [Citation(s) in RCA: 192] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
BACKGROUND The role of genetics in early-onset Parkinson's disease has been established, but whether there is a genetic contribution to the more common, late-onset form remains uncertain. METHODS We reviewed the medical records and confirmed the diagnosis of Parkinson's disease in 772 living and deceased patients in whom the disease had been diagnosed during the previous 50 years in Iceland. With the use of an extensive computerized data base containing genealogic information on 610,920 people in Iceland during the past 11 centuries, several analyses were conducted to determine whether the patients were more related to each other than random members of the population (control subjects). RESULTS Patients with Parkinson's disease, including a subgroup of 560 patients with late-onset disease (onset at >50 years of age), were significantly more related to each other than were subjects in matched groups of controls, and this relatedness extended beyond the nuclear family. The risk ratio for Parkinson's disease was 6.7 (95 percent confidence interval, 4.3 to 9.6) for siblings, 3.2 (95 percent confidence interval, 1.2 to 7.8) for offspring, and 2.7 (95 percent confidence interval, 1.6 to 3.9) for nephews and nieces of patients with late-onset Parkinson's disease. CONCLUSIONS Late-onset Parkinson's disease has a genetic component as well as an environmental component.
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Bailey ME, Matthews DA, Riley BP, Albrecht BE, Kostrzewa M, Hicks AA, Harris R, Müller U, Darlison MG, Johnson KJ. Genomic mapping and evolution of human GABA(A) receptor subunit gene clusters. Mamm Genome 1999; 10:839-43. [PMID: 10430673 DOI: 10.1007/s003359901101] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Affiliation(s)
- M E Bailey
- Division of Molecular Genetics, Institute of Biomedical and Life Sciences, University of Glasgow, Anderson College, 56 Dumbarton Road, Glasgow G11 6NU, UK
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Abstract
Alterations in gamma-aminobutyric acid (GABA) neurotransmission have been indirectly implicated in the pathogenesis of schizophrenia. Using nine multiplex pedigrees, we tested for linkage between schizophrenia and simple sequence repeat polymorphisms for the GABAA receptor alpha 1, alpha 2, alpha 4, alpha 5, alpha 6, beta 1 and beta 3 subunit genes. Evidence of linkage was not found when assuming either autosomal dominant or autosomal recessive inheritance. The non-parametric sib pair test also did not reveal significant evidence of deviation from expected segregation ratios.
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Affiliation(s)
- W Byerley
- University of Utah School of Medicine, Department of Psychiatry, Salt Lake City 84132, USA
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Hicks AA, Bailey ME, Riley BP, Kamphuis W, Siciliano MJ, Johnson KJ, Darlison MG. Further evidence for clustering of human GABAA receptor subunit genes: localization of the alpha 6-subunit gene (GABRA6) to distal chromosome 5q by linkage analysis. Genomics 1994; 20:285-8. [PMID: 8020978 DOI: 10.1006/geno.1994.1167] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
GABAA receptors are hetero-oligomeric ion-channel complexes that are composed of combinations of alpha, beta, gamma, and delta subunits and play a major role in inhibitory neuro-transmission in the mammalian brain. We report here a microsatellite polymorphism within the human alpha 6-subunit gene (GABRA6). Mapping of this marker in a human-hamster hybrid cell-line panel and typing of the repeat in the Centre d'Etude du Polymorphisme Human (CEPH) reference families enabled the localization of this gene to chromosome 5q and established its linkage to the GABAA receptor alpha 1-subunit gene (GA-BRA1) with a maximum lod score (Zmax) of 39.87 at a theta of 0.069 (males) and 0.100 (females). These results reveal the clustering of GABRA6, GABRA1, and the GABAA receptor gamma 2-subunit gene (GABRG2) on distal chromosome 5q.
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Affiliation(s)
- A A Hicks
- MRC Molecular Neurobiology Unit, MRC Centre, Cambridge, United Kingdom
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Coon H, Hicks AA, Bailey ME, Hoff M, Holik J, Harvey RJ, Johnson KJ, Darlison MG, Reimherr F, Wender P. Analysis of GABAA receptor subunit genes in multiplex pedigrees with manic depression. Psychiatr Genet 1994; 4:185-91. [PMID: 7719705 DOI: 10.1097/00041444-199400430-00009] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
The gamma-aminobutyric acid (GABA) neurotransmitter system has been implicated in the pathogenesis of manic depression. Tests of this hypothesis can now be carried out due to the recent characterization of simple sequence repeat polymorphisms for the GABAA receptor alpha 1, alpha 2, alpha 4, alpha 5, alpha 6, beta 1, beta 3 and gamma 2 subunit genes. Using both parametric and non-parametric methods, we tested for linkage between manic depression and these polymorphisms in six multi-generational pedigrees. No evidence of linkage was found.
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Affiliation(s)
- H Coon
- Department of Psychiatry, University of Utah Medical School, Salt Lake City 84132
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Smirnova T, Laroche S, Errington ML, Hicks AA, Bliss TV, Mallet J. Transsynaptic expression of a presynaptic glutamate receptor during hippocampal long-term potentiation. Science 1993; 262:433-6. [PMID: 8105538 DOI: 10.1126/science.8105538] [Citation(s) in RCA: 48] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
Repetitive activation of excitatory synapses in the hippocampus produces a persistent enhancement of synaptic efficiency known as long-term potentiation (LTP). In anesthetized and in freely moving rats, the induction of LTP in the perforant path led to a transient increase in the amount of messenger RNA (mRNA) coding for a presynaptic glutamate receptor (GR33) in dentate granule cells. The amount of GR33 mRNA was increased for at least 5 hours after the induction of LTP but was indistinguishable from control values 1 day after induction. The N-methyl-D-aspartate receptor antagonist 2-aminophosphonovalerate prevented the induction of both LTP and the increase in GR33 mRNA. The amount of GR33 protein was increased in the mossy fiber terminal zone of dentate granule cells 5 hours after the induction of LTP. These results suggest that the induction of LTP in synapses at one stage in a neural network may lead to modification in synaptic function at the next stage in the network.
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Affiliation(s)
- T Smirnova
- Laboratoire de génétique moléculaire de la neurotransmission et des processus neurodégénératifs, Centre National de la Recherche Scientifique (CNRS), Gif-sur-Yvette, France
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Johnson KJ, Sander T, Hicks AA, van Marle A, Janz D, Mullan MJ, Riley BP, Darlison MG. Confirmation of the localization of the human GABAA receptor alpha 1-subunit gene (GABRA1) to distal 5q by linkage analysis. Genomics 1992; 14:745-8. [PMID: 1330891 DOI: 10.1016/s0888-7543(05)80178-8] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
The GABAA receptor is the major inhibitory neurotransmitter receptor in the mammalian brain. To date, 14 genes that encode subunits of this receptor have been identified; these appear to be scattered throughout the human genome and are under investigation as candidate loci for a number of neurological and psychiatric disorders. We report here a highly polymorphic (dC-dA)n repeat within the human alpha 1-subunit gene (GABRA1). Typing of this marker in the Centre d'Etude du Polymorphisme Humain (CEPH) panel of families confirms the previous assignment of the GABRA1 locus to the distal portion of chromosome 5q by demonstrating linkage to the markers CRI-L45 (D5S61) (Zmax = 11.00, theta max = 0.15), CRI-V1022 (D5S54) (Zmax = 7.25, theta max = 0.20), and CRI-P148 (D5S72) (Zmax = 5.71, theta max = 0.24).
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Affiliation(s)
- K J Johnson
- Department of Biochemistry and Molecular Genetics, St. Mary's Hospital Medical School, Imperial College, London, United Kingdom
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Hicks AA, Johnson KJ, Barnard EA, Darlison MG. Dinucleotide repeat polymorphism in the human X-linked GABAA receptor alpha 3-subunit gene. Nucleic Acids Res 1991; 19:4016. [PMID: 1650462 PMCID: PMC328518 DOI: 10.1093/nar/19.14.4016] [Citation(s) in RCA: 23] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
Affiliation(s)
- A A Hicks
- MRC Molecular Neurobiology Unit, Medical Research Council Centre, Cambridge, UK
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Bateson AN, Harvey RJ, Wisden W, Glencorse TA, Hicks AA, Hunt SP, Barnard EA, Darlison MG. The chicken GABAA receptor alpha 1 subunit: cDNA sequence and localization of the corresponding mRNA. Brain Res Mol Brain Res 1991; 9:333-9. [PMID: 1710013 DOI: 10.1016/0169-328x(91)90081-8] [Citation(s) in RCA: 39] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
We report the sequence of a complementary DNA (cDNA) that encodes the chicken GABAA receptor alpha 1 subunit, which is extremely homologous to mammalian alpha 1 subunits. The distribution of alpha 1 subunit transcripts is shown to correlate mainly, but not completely, with the previously-reported pattern of benzodiazepine type I (BZI) binding sites in the avian brain. These results suggest that the alpha 1 subunit may not necessarily be restricted to receptors having BZI pharmacology.
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Affiliation(s)
- A N Bateson
- MRC Molecular Neurobiology Unit, MRC Centre, Cambridge, U.K
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Morris BJ, Hicks AA, Wisden W, Darlison MG, Hunt SP, Barnard EA. Distinct regional expression of nicotinic acetylcholine receptor genes in chick brain. Brain Res Mol Brain Res 1990; 7:305-15. [PMID: 2163006 DOI: 10.1016/0169-328x(90)90081-n] [Citation(s) in RCA: 58] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
Four genes (alpha 2, alpha 3, alpha 4 and beta 2) have been reported as encoding subunits of the nicotinic acetylcholine receptor (nAChR) in chicken brain. The mRNAs transcribed from these genes have here been localised to particular regions using in situ hybridisation histochemistry. The beta 2 mRNA was clearly the most abundant transcript, being widely distributed throughout the chick brain. In the cerebellum, all four mRNA species were present, although they showed different cellular patterns of distribution. Only alpha 2 mRNA and beta 2 mRNA were found in significant amounts in the optic tectum. In the lateral spiriform nucleus, while alpha 2 mRNA, alpha 4 mRNA and beta 2 mRNA were all very abundant, the alpha 4 mRNA was localised to a subgroup of neurons containing alpha 2 mRNA and beta 2 mRNA. This represents the first evidence that individual cells may express two different nAChR alpha subunit genes in vivo. The distributions of the 4 mRNA species showed few common features. This suggests that other neuronal nAChR genes remain to be identified, and that these 4 genes are not generally expressed in the same cells to constitute a single macromolecular complex. The results therefore provide evidence for nAChR heterogeneity in the central nervous system.
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Affiliation(s)
- B J Morris
- MRC Molecular Neurobiology Unit, MRC Centre, Cambridge, U.K
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