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Block A, Ahmed MM, Dhanasekaran AR, Tong S, Gardiner KJ. Sex differences in protein expression in the mouse brain and their perturbations in a model of Down syndrome. Biol Sex Differ 2015; 6:24. [PMID: 26557979 PMCID: PMC4640233 DOI: 10.1186/s13293-015-0043-9] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/24/2015] [Accepted: 11/01/2015] [Indexed: 01/08/2023] Open
Abstract
Background While many sex differences in structure and function of the mammalian brain have been described, the molecular correlates of these differences are not broadly known. Also unknown is how sex differences at the protein level are perturbed by mutations that lead to intellectual disability (ID). Down syndrome (DS) is the most common genetic cause of ID and is due to trisomy of human chromosome 21 (Hsa21) and the resulting increased expression of Hsa21-encoded genes. The Dp(10)1Yey mouse model (Dp10) of DS is trisomic for orthologs of 39 Hsa21 protein-coding genes that map to mouse chromosome 10 (Mmu10), including four genes with known sex differences in functional properties. How these genes contribute to the DS cognitive phenotype is not known. Methods Using reverse phase protein arrays, levels of ~100 proteins/protein modifications were measured in the hippocampus, cerebellum, and cortex of female and male controls and their trisomic Dp10 littermates. Proteins were chosen for their known roles in learning/memory and synaptic plasticity and include components of the MAPK, MTOR, and apoptosis pathways, immediate early genes, and subunits of ionotropic glutamate receptors. Protein levels were compared between genotypes, sexes, and brain regions using a three-level mixed effects model and the Benjamini-Hochberg correction for multiple testing. Results In control mice, levels of approximately one half of the proteins differ significantly between females and males in at least one brain region; in the hippocampus alone, levels of 40 % of the proteins are significantly higher in females. Trisomy of the Mmu10 segment differentially affects female and male profiles, perturbing protein levels most in the cerebellum of female Dp10 and most in the hippocampus of male Dp10. Cortex is minimally affected by sex and genotype. Diverse pathways and processes are implicated in both sex and genotype differences. Conclusions The extensive sex differences in control mice in levels of proteins involved in learning/memory illustrate the molecular complexity underlying sex differences in normal neurological processes. The sex-specific abnormalities in the Dp10 suggest the possibility of sex-specific phenotypic features in DS and reinforce the need to use female as well as male mice, in particular in preclinical evaluations of drug responses. Electronic supplementary material The online version of this article (doi:10.1186/s13293-015-0043-9) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Aaron Block
- Department of Pediatrics, Linda Crnic Institute for Down Syndrome, Aurora, USA
| | - Md Mahiuddin Ahmed
- Department of Pediatrics, Linda Crnic Institute for Down Syndrome, Aurora, USA
| | | | - Suhong Tong
- Colorado School of Public Health, Aurora, USA
| | - Katheleen J Gardiner
- Department of Pediatrics, Linda Crnic Institute for Down Syndrome, Aurora, USA ; Human Medical Genetics and Genomics, and Neuroscience Programs, University of Colorado Denver School of Medicine, 12700 E 19th Avenue, Mail Stop 8608, Aurora, CO 80045 USA
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Abstract
RNAs adopt diverse folded structures that are essential for function and thus play critical roles in cellular biology. A striking example of this is the ribosome, a complex, three-dimensionally folded macromolecular machine that orchestrates protein synthesis. Advances in RNA biochemistry, structural and molecular biology, and bioinformatics have revealed other non-coding RNAs whose functions are dictated by their structure. It is not surprising that aberrantly folded RNA structures contribute to disease. In this Review, we provide a brief introduction into RNA structural biology and then describe how RNA structures function in cells and cause or contribute to neurological disease. Finally, we highlight successful applications of rational design principles to provide chemical probes and lead compounds targeting structured RNAs. Based on several examples of well-characterized RNA-driven neurological disorders, we demonstrate how designed small molecules can facilitate the study of RNA dysfunction, elucidating previously unknown roles for RNA in disease, and provide lead therapeutics.
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Affiliation(s)
- Viachaslau Bernat
- Department of Chemistry, The Scripps Research Institute, 130 Scripps Way, Jupiter, FL 33458, USA
| | - Matthew D Disney
- Department of Chemistry, The Scripps Research Institute, 130 Scripps Way, Jupiter, FL 33458, USA.
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George CX, John L, Samuel CE. An RNA editor, adenosine deaminase acting on double-stranded RNA (ADAR1). J Interferon Cytokine Res 2015; 34:437-46. [PMID: 24905200 DOI: 10.1089/jir.2014.0001] [Citation(s) in RCA: 55] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
Adenosine deaminase acting on RNA1 (ADAR1) catalyzes the C6 deamination of adenosine (A) to produce inosine (I) in regions of RNA with double-stranded (ds) character. This process is known as A-to-I RNA editing. Alternative promoters drive the expression of the Adar1 gene and alternative splicing gives rise to transcripts that encode 2 ADAR1 protein size isoforms. ADAR1 p150 is an interferon (IFN)-inducible dsRNA adenosine deaminase found in the cytoplasm and nucleus, whereas ADAR1 p110 is constitutively expressed and nuclear in localization. Dependent on the duplex structure of the dsRNA substrate, deamination of adenosine by ADAR can be either highly site-selective or nonspecific. A-to-I editing can alter the stability of RNA structures and the coding of RNA as I is read as G instead of A by ribosomes during mRNA translation and by polymerases during RNA replication. A-to-I editing is of broad physiologic significance. Both the production and the action of IFNs, and hence the subsequent interaction of viruses with their hosts, are among the processes affected by A-to-I editing.
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Affiliation(s)
- Cyril X George
- Department of Molecular, Cellular and Developmental Biology, University of California , Santa Barbara, California
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4
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Abstract
Modified RNA molecules have recently been shown to regulate nervous system functions. This mini-review and associated mini-symposium provide an overview of the types and known functions of novel modified RNAs in the nervous system, including covalently modified RNAs, edited RNAs, and circular RNAs. We discuss basic molecular mechanisms involving RNA modifications as well as the impact of modified RNAs and their regulation on neuronal processes and disorders, including neural fate specification, intellectual disability, neurodegeneration, dopamine neuron function, and substance use disorders.
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Shu Y, Pi F, Sharma A, Rajabi M, Haque F, Shu D, Leggas M, Evers BM, Guo P. Stable RNA nanoparticles as potential new generation drugs for cancer therapy. Adv Drug Deliv Rev 2014; 66:74-89. [PMID: 24270010 DOI: 10.1016/j.addr.2013.11.006] [Citation(s) in RCA: 181] [Impact Index Per Article: 18.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2013] [Revised: 10/11/2013] [Accepted: 11/13/2013] [Indexed: 12/13/2022]
Abstract
Human genome sequencing revealed that only ~1.5% of the DNA sequence coded for proteins. More and more evidence has uncovered that a substantial part of the 98.5% so-called "junk" DNAs actually code for noncoding RNAs. Two milestones, chemical drugs and protein drugs, have already appeared in the history of drug development, and it is expected that the third milestone in drug development will be RNA drugs or drugs that target RNA. This review focuses on the development of RNA therapeutics for potential cancer treatment by applying RNA nanotechnology. A therapeutic RNA nanoparticle is unique in that its scaffold, ligand, and therapeutic component can all be composed of RNA. The special physicochemical properties lend to the delivery of siRNA, miRNA, ribozymes, or riboswitches; imaging using fluogenenic RNA; and targeting using RNA aptamers. With recent advances in solving the chemical, enzymatic, and thermodynamic stability issues, RNA nanoparticles have been found to be advantageous for in vivo applications due to their uniform nano-scale size, precise stoichiometry, polyvalent nature, low immunogenicity, low toxicity, and target specificity. In vivo animal studies have revealed that RNA nanoparticles can specifically target tumors with favorable pharmacokinetic and pharmacodynamic parameters without unwanted accumulation in normal organs. This review summarizes the key studies that have led to the detailed understanding of RNA nanoparticle formation as well as chemical and thermodynamic stability issue. The methods for RNA nanoparticle construction, and the current challenges in the clinical application of RNA nanotechnology, such as endosome trapping and production costs, are also discussed.
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Affiliation(s)
- Yi Shu
- Markey Cancer Center, University of Kentucky, Lexington, KY 40536, USA; Department of Pharmaceutical Sciences, University of Kentucky, Lexington, KY 40536, USA
| | - Fengmei Pi
- Markey Cancer Center, University of Kentucky, Lexington, KY 40536, USA; Department of Pharmaceutical Sciences, University of Kentucky, Lexington, KY 40536, USA
| | - Ashwani Sharma
- Markey Cancer Center, University of Kentucky, Lexington, KY 40536, USA; Department of Pharmaceutical Sciences, University of Kentucky, Lexington, KY 40536, USA
| | - Mehdi Rajabi
- Markey Cancer Center, University of Kentucky, Lexington, KY 40536, USA; Department of Pharmaceutical Sciences, University of Kentucky, Lexington, KY 40536, USA
| | - Farzin Haque
- Markey Cancer Center, University of Kentucky, Lexington, KY 40536, USA; Department of Pharmaceutical Sciences, University of Kentucky, Lexington, KY 40536, USA
| | - Dan Shu
- Markey Cancer Center, University of Kentucky, Lexington, KY 40536, USA; Department of Pharmaceutical Sciences, University of Kentucky, Lexington, KY 40536, USA
| | - Markos Leggas
- Markey Cancer Center, University of Kentucky, Lexington, KY 40536, USA; Department of Pharmaceutical Sciences, University of Kentucky, Lexington, KY 40536, USA
| | - B Mark Evers
- Markey Cancer Center, University of Kentucky, Lexington, KY 40536, USA
| | - Peixuan Guo
- Markey Cancer Center, University of Kentucky, Lexington, KY 40536, USA; Department of Pharmaceutical Sciences, University of Kentucky, Lexington, KY 40536, USA.
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Kamei M, Kasperski K, Fuller M, Parkinson-Lawrence EJ, Karageorgos L, Belakhov V, Baasov T, Hopwood JJ, Brooks DA. Aminoglycoside-Induced Premature Stop Codon Read-Through of Mucopolysaccharidosis Type I Patient Q70X and W402X Mutations in Cultured Cells. JIMD Rep 2013; 13:139-47. [PMID: 24193436 DOI: 10.1007/8904_2013_270] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/19/2013] [Revised: 08/13/2013] [Accepted: 09/25/2013] [Indexed: 12/24/2022] Open
Abstract
The premature stop codon mutations, Q70X and W402X, are the most common α-L-iduronidase gene (IDUA) mutations in mucopolysaccharidosis type I (MPS I) patients. Read-through drugs have been used to suppress premature stop codons, and this can potentially be used to treat patients who have this type of mutation. We examined the effects of aminoglycoside treatment on the IDUA mutations Q70X and W402X in cultured cells and show that 4,5-disubstituted aminoglycosides induced more read-through for the W402X mutation, while 4,6-disubstituted aminoglycosides promoted more read-through for the Q70X mutation: lividomycin (4,5-disubstituted) induced a 7.8-fold increase in α-L-iduronidase enzyme activity for the W402X mutation; NB54 (4,5-disubstituted) induced a 3.7 fold increase in the amount of α-L-iduronidase enzyme activity for the W402X mutation, but had less effect on the Q70X mutation, whereas gentamicin (4,6-disubstituted) had the reverse effect on read-through for both mutations. The predicted mRNA secondary structural changes for both mutations were markedly different, which may explain these different effects on read-through for these two premature stop codons.
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Affiliation(s)
- Makoto Kamei
- Mechanisms in Cell Biology and Diseases Research Group, School of Pharmacy and Medical Sciences, Sansom Institute for Health Research, University of South Australia, Adelaide, South Australia, 5001, Australia,
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RNA editing and drug discovery for cancer therapy. ScientificWorldJournal 2013; 2013:804505. [PMID: 23737728 PMCID: PMC3655661 DOI: 10.1155/2013/804505] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2013] [Accepted: 04/08/2013] [Indexed: 12/26/2022] Open
Abstract
RNA editing is vital to provide the RNA and protein complexity to regulate the gene expression. Correct RNA editing maintains the cell function and organism development. Imbalance of the RNA editing machinery may lead to diseases and cancers. Recently, RNA editing has been recognized as a target for drug discovery although few studies targeting RNA editing for disease and cancer therapy were reported in the field of natural products. Therefore, RNA editing may be a potential target for therapeutic natural products. In this review, we provide a literature overview of the biological functions of RNA editing on gene expression, diseases, cancers, and drugs. The bioinformatics resources of RNA editing were also summarized.
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Tariq A, Jantsch MF. Transcript diversification in the nervous system: a to I RNA editing in CNS function and disease development. Front Neurosci 2012; 6:99. [PMID: 22787438 PMCID: PMC3391646 DOI: 10.3389/fnins.2012.00099] [Citation(s) in RCA: 64] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2012] [Accepted: 06/14/2012] [Indexed: 12/16/2022] Open
Abstract
RNA editing by adenosine deaminases that act on RNA converts adenosines to inosines in coding and non-coding regions of mRNAs. Inosines are interpreted as guanosines and hence, this type of editing can change codons, alter splice patterns, or influence the fate of an RNA. A to I editing is most abundant in the central nervous system (CNS). Here, targets for this type of nucleotide modification frequently encode receptors and channels. In many cases, the editing-induced amino acid exchanges alter the properties of the receptors and channels. Consistently, changes in editing patterns are frequently found associated with diseases of the CNS. In this review we describe the mechanisms of RNA editing and focus on target mRNAs of editing that are functionally relevant to normal and aberrant CNS activity.
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Affiliation(s)
- Aamira Tariq
- Max F. Perutz Laboratories, Department of Chromosome Biology, University of Vienna Vienna, Austria
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9
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Lyddon R, Navarrett S, Dracheva S. Ionotropic glutamate receptor mRNA editing in the prefrontal cortex: no alterations in schizophrenia or bipolar disorder. J Psychiatry Neurosci 2012; 37:267-72. [PMID: 22469055 PMCID: PMC3380098 DOI: 10.1503/jpn.110107] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
BACKGROUND Dysfunction of glutamate neurotransmission has been implicated in the pathology of schizophrenia and bipolar disorder, and one mechanism by which glutamate signalling can be altered is through RNA editing of ionotropic glutamate receptors (iGluRs). The objectives of the present study were to evaluate the editing status of iGluRs in the human prefrontal cortex, determine whether iGluR editing is associated with psychiatric disease or suicide and evaluate a potential association between editing and alternative splicing in the α-amino-3-hydroxy-5-methylisoxazole-4-propionate (AMPA) iGluR subunits' pre-mRNA. METHODS We studied specimens derived from patients with antemortem diagnoses of bipolar disorder (n = 31) or schizophrenia (n = 34) who died by suicide or other causes, and from psychiatrically healthy controls (n = 34) who died from causes other than suicide. The RNA editing at all 8 editing sites within AMPA (GluA2-4 subunits) and kainate (GluK1-2 subunits) iGluRs was analyzed using a novel real-time quantitative polymerase chain reaction assay. RESULTS No differences in editing were detected among schizophrenia, bipolar or control groups or between suicide completers and patients who died from causes other than suicide. The editing efficiency was significantly higher in the flop than in the flip splicoforms of GluA3-4 AMPA subunits (all p < 0.001). LIMITATIONS The study is limited by the near absence of specimens from medicationnaive psychiatric patients and considerable variation in medication regimens among individuals, both of which introduce considerable uncertainty into the analysis of potential medication effects. CONCLUSION We found that iGluR RNA editing status was not associated with bipolar disorder, schizophrenia or suicide. Differences in editing between flip and flop splicoforms suggest that glutamate sensitivity of receptors containing GluA3 and/or GluA4 flop subunits is moderated as a result of increased editing.
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Affiliation(s)
| | | | - Stella Dracheva
- Correspondence to: S. Dracheva, Psychiatry Research (4F-02), Bronx VA Medical Center, 130 West Kingsbridge Rd., Bronx NY 10468;
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Wang Q. RNA editing catalyzed by ADAR1 and its function in mammalian cells. BIOCHEMISTRY (MOSCOW) 2012; 76:900-11. [PMID: 22022963 DOI: 10.1134/s0006297911080050] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
In mammalian cells two active enzymes, ADAR1 and ADAR2, carry out A-to-I RNA editing. These two editases share many common features in their protein structures, catalytic activities, and substrate requirements. However, the phenotypes of the knockout animals are remarkably different, which indicate the distinct functions they play. The most striking effect of ADAR1 knockout is cell death and interruption of embryonic development that are not observed in ADAR2 knockout. Evidences have shown that ADAR1 plays critical roles in the differentiating cells in embryo and adult tissues to support the cell's survival and permit their further differentiation and maturation. However, our knowledge in understanding of the mechanism by which ADAR1 exerts its unique effects is very limited. Many efforts had been made trying to understand why ADAR1 is so important that it is indispensible for animal survival, including studies that identify the RNA editing substrates and studies on non-editing mechanisms. The interest of this review is focused on the question why ADAR1 and not ADAR2 is required for cell survival. Therefore, only the data, published and unpublished, potentially connecting ADAR1 to its cell death effect is selectively cited and discussed here. The features of cell death caused by ADAR1 deletion are summarized. Potential involvement of interferon and protein kinase RNA-activated (PKR) pathways is proposed, but obviously more experimental evaluations are needed.
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Affiliation(s)
- Qingde Wang
- University of Pittsburgh, Department of Medicine, Division of Hematology and Oncology, University of Pittsburgh Cancer Institute, PA 15232, USA.
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11
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Posttranscriptional recoding by RNA editing. ADVANCES IN PROTEIN CHEMISTRY AND STRUCTURAL BIOLOGY 2012; 86:193-224. [PMID: 22243585 DOI: 10.1016/b978-0-12-386497-0.00006-2] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
The posttranscriptional recoding of nuclear RNA transcripts has emerged as an important regulatory mechanism during eukaryotic gene expression. In particular the deamination of adenosine to inosine (interpreted by the translational machinery as a guanosine) is a frequent event that can recode the meaning of amino acid codons in translated exons, lead to structural changes in the RNA fold, or may affect splice consensus or regulatory sequence sites in noncoding exons or introns and modulate the biogenesis of small RNAs. The molecular mechanism of how the RNA editing machinery and its substrates recognize and interact with each other is not understood well enough to allow for the ab initio delineation of bona fide RNA editing sites. However, progress in the identification of various physiological modification sites and their characterization has given important insights regarding molecular features and events critical for productive RNA editing reactions. In addition, structural studies using components of the RNA editing machinery and together with editing competent substrate molecules have provided information on the chemical mechanism of adenosine deamination within the context of RNA molecules. Here, I give an overview of the process of adenosine deamination RNA editing and describe its relationship to other RNA processing events and its currently established roles in gene regulation.
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13
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Tran T, Disney MD. Molecular recognition of 6'-N-5-hexynoate kanamycin A and RNA 1x1 internal loops containing CA mismatches. Biochemistry 2011; 50:962-9. [PMID: 21207945 PMCID: PMC3106427 DOI: 10.1021/bi101724h] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
In our previous study to identify the RNA internal loops that bind an aminoglycoside derivative, we determined that 6'-N-5-hexynoate kanamycin A prefers to bind 1x1 nucleotide internal loops containing C·A mismatches. In this present study, the molecular recognition between a variety of RNAs that are mutated around the C·A loop and the ligand was investigated. Studies show that both loop nucleotides and loop closing pairs affect binding affinity. Most interestingly, it was shown that there is a correlation between the thermodynamic stability of the C·A internal loops and ligand affinity. Specifically, C·A loops that had relatively high or low stability bound the ligand most weakly whereas loops with intermediate stability bound the ligand most tightly. In contrast, there is no correlation between the likelihood that a loop forms a C-A(+) pair at lower pH and ligand affinity. It was also found that a 1x1 nucleotide C·A loop that bound to the ligand with the highest affinity is identical to the consensus site in RNAs that are edited by adenosine deaminases acting on RNA type 2 (ADAR2). These studies provide a detailed investigation of factors affecting small molecule recognition of internal loops containing C·A mismatches, which are present in a variety of RNAs that cause disease.
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Affiliation(s)
- Tuan Tran
- Department of Chemistry and The Center of Excellence in Bioinformatics and Life Sciences, University at Buffalo, The State University of New York, Natural Sciences Complex, Buffalo, NY 14260
- Department of Chemistry, The Scripps Research Institute, Scripps Florida, 130 Scripps Way #3A1, Jupiter, FL 33458
| | - Matthew D. Disney
- Department of Chemistry, The Scripps Research Institute, Scripps Florida, 130 Scripps Way #3A1, Jupiter, FL 33458
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Anthony K, Gallo JM. Aberrant RNA processing events in neurological disorders. Brain Res 2010; 1338:67-77. [DOI: 10.1016/j.brainres.2010.03.008] [Citation(s) in RCA: 63] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2010] [Revised: 02/24/2010] [Accepted: 03/03/2010] [Indexed: 12/12/2022]
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Olaghere da Silva UB, Morabito MV, Canal CE, Airey DC, Emeson RB, Sanders-Bush E. Impact of RNA editing on functions of the serotonin 2C receptor in vivo. Front Neurosci 2010; 4:26. [PMID: 20582266 PMCID: PMC2858556 DOI: 10.3389/neuro.23.001.2010] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2009] [Accepted: 01/20/2010] [Indexed: 01/07/2023] Open
Abstract
Transcripts encoding 5-HT(2C) receptors are modified posttranscriptionally by RNA editing, generating up to 24 protein isoforms. In recombinant cells, the fully edited isoform, 5-HT(2C-VGV), exhibits blunted G-protein coupling and reduced constitutive activity. The present studies examine the signal transduction properties of 5-HT(2C-VGV) receptors in brain to determine the in vivo consequences of altered editing. Using mice solely expressing the 5-HT(2C-VGV) receptor (VGV/Y), we demonstrate reduced G-protein coupling efficiency and high-affinity agonist binding of brain 5-HT(2C-VGV) receptors. However, enhanced behavioral sensitivity to a 5-HT(2C) receptor agonist was also seen in mice expressing 5-HT(2C-VGV) receptors, an unexpected finding given the blunted G-protein coupling. In addition, mice expressing 5-HT(2C-VGV) receptors had greater sensitivity to a 5-HT(2C) inverse agonist/antagonist enhancement of dopamine turnover relative to wild-type mice. These behavioral and biochemical results are most likely explained by increases in 5-HT(2C) receptor binding sites in the brains of mice solely expressing 5-HT(2C-VGV) receptors. We conclude that 5-HT(2C-VGV) receptor signaling in brain is blunted, but this deficiency is masked by a marked increase in 5-HT(2C) receptor binding site density in mice solely expressing the VGV isoform. These findings suggest that RNA editing may regulate the density of 5-HT(2C) receptor binding sites in brain. We further caution that the pattern of 5-HT(2C) receptor RNA isoforms may not reflect the pattern of protein isoforms, and hence the inferred overall function of the receptor.
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Affiliation(s)
| | - Michael V. Morabito
- Center for Molecular Neuroscience, Vanderbilt University School of MedicineNashville, TN, USA
| | - Clinton E. Canal
- Center for Molecular Neuroscience, Vanderbilt University School of MedicineNashville, TN, USA
- Department of Pharmacology, Vanderbilt University School of MedicineNashville, TN, USA
| | - David C. Airey
- Center for Molecular Neuroscience, Vanderbilt University School of MedicineNashville, TN, USA
- Department of Pharmacology, Vanderbilt University School of MedicineNashville, TN, USA
| | - Ronald B. Emeson
- Center for Molecular Neuroscience, Vanderbilt University School of MedicineNashville, TN, USA
- Department of Pharmacology, Vanderbilt University School of MedicineNashville, TN, USA
- Department of Psychiatry, Vanderbilt University School of MedicineNashville, TN, USA
- Department of Molecular Physiology and Biophysics, Vanderbilt University School of MedicineNashville, TN, USA
| | - Elaine Sanders-Bush
- Center for Molecular Neuroscience, Vanderbilt University School of MedicineNashville, TN, USA
- Department of Pharmacology, Vanderbilt University School of MedicineNashville, TN, USA
- Department of Psychiatry, Vanderbilt University School of MedicineNashville, TN, USA
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Schirle NT, Goodman RA, Krishnamurthy M, Beal PA. Selective inhibition of ADAR2-catalyzed editing of the serotonin 2c receptor pre-mRNA by a helix-threading peptide. Org Biomol Chem 2010; 8:4898-904. [DOI: 10.1039/c0ob00309c] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
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