1
|
Mohaupt P, Vialaret J, Hirtz C, Lehmann S. Readthrough isoform of aquaporin-4 (AQP4) as a therapeutic target for Alzheimer's disease and other proteinopathies. Alzheimers Res Ther 2023; 15:170. [PMID: 37821965 PMCID: PMC10566184 DOI: 10.1186/s13195-023-01318-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2023] [Accepted: 09/27/2023] [Indexed: 10/13/2023]
Abstract
The glymphatic system is a crucial component in preserving brain homeostasis by facilitating waste clearance from the central nervous system (CNS). Aquaporin-4 (AQP4) water channels facilitate the continuous interchange between cerebrospinal fluid and brain interstitial fluid by convective flow movement. This flow is responsible for guiding proteins and metabolites away from the CNS. Proteinopathies are neurological conditions characterized by the accumulation of aggregated proteins or peptides in the brain. In Alzheimer's disease (AD), the deposition of amyloid-β (Aβ) peptides causes the formation of senile plaques. This accumulation has been hypothesized to be a result of the imbalance between Aβ production and clearance. Recent studies have shown that an extended form of AQP4 increases Aβ clearance from the brain. In this mini-review, we present a summary of these findings and explore the potential for future therapeutic strategies aiming to boost waste clearance in AD.
Collapse
Affiliation(s)
- Pablo Mohaupt
- LBPC-PPC, Université de Montpellier, IRMB CHU de Montpellier, INM INSERM, Montpellier, France
| | - Jérôme Vialaret
- LBPC-PPC, Université de Montpellier, IRMB CHU de Montpellier, INM INSERM, Montpellier, France
| | - Christophe Hirtz
- LBPC-PPC, Université de Montpellier, IRMB CHU de Montpellier, INM INSERM, Montpellier, France
| | - Sylvain Lehmann
- LBPC-PPC, Université de Montpellier, IRMB CHU de Montpellier, INM INSERM, Montpellier, France
| |
Collapse
|
2
|
Mohaupt P, Roucou X, Delaby C, Vialaret J, Lehmann S, Hirtz C. The alternative proteome in neurobiology. Front Cell Neurosci 2022; 16:1019680. [PMID: 36467612 PMCID: PMC9712206 DOI: 10.3389/fncel.2022.1019680] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2022] [Accepted: 11/02/2022] [Indexed: 10/13/2023] Open
Abstract
Translation involves the biosynthesis of a protein sequence following the decoding of the genetic information embedded in a messenger RNA (mRNA). Typically, the eukaryotic mRNA was considered to be inherently monocistronic, but this paradigm is not in agreement with the translational landscape of cells, tissues, and organs. Recent ribosome sequencing (Ribo-seq) and proteomics studies show that, in addition to currently annotated reference proteins (RefProt), other proteins termed alternative proteins (AltProts), and microproteins are encoded in regions of mRNAs thought to be untranslated or in transcripts annotated as non-coding. This experimental evidence expands the repertoire of functional proteins within a cell and potentially provides important information on biological processes. This review explores the hitherto overlooked alternative proteome in neurobiology and considers the role of AltProts in pathological and healthy neuromolecular processes.
Collapse
Affiliation(s)
- Pablo Mohaupt
- LBPC-PPC, Université de Montpellier, IRMB CHU de Montpellier, INM INSERM, Montpellier, France
| | - Xavier Roucou
- Department of Biochemistry and Functional Genomics, Université de Sherbrooke, Sherbrooke, QC, Canada
| | - Constance Delaby
- LBPC-PPC, Université de Montpellier, IRMB CHU de Montpellier, INM INSERM, Montpellier, France
| | - Jérôme Vialaret
- LBPC-PPC, Université de Montpellier, IRMB CHU de Montpellier, INM INSERM, Montpellier, France
| | - Sylvain Lehmann
- LBPC-PPC, Université de Montpellier, IRMB CHU de Montpellier, INM INSERM, Montpellier, France
| | - Christophe Hirtz
- LBPC-PPC, Université de Montpellier, IRMB CHU de Montpellier, INM INSERM, Montpellier, France
| |
Collapse
|
3
|
The dark proteome: translation from noncanonical open reading frames. Trends Cell Biol 2022; 32:243-258. [PMID: 34844857 PMCID: PMC8934435 DOI: 10.1016/j.tcb.2021.10.010] [Citation(s) in RCA: 48] [Impact Index Per Article: 24.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2021] [Revised: 10/26/2021] [Accepted: 10/29/2021] [Indexed: 02/07/2023]
Abstract
Omics-based technologies have revolutionized our understanding of the coding potential of the genome. In particular, these studies revealed widespread unannotated open reading frames (ORFs) throughout genomes and that these regions have the potential to encode novel functional (micro-)proteins and/or hold regulatory roles. However, despite their genomic prevalence, relatively few of these noncanonical ORFs have been functionally characterized, likely in part due to their under-recognition by the broader scientific community. The few that have been investigated in detail have demonstrated their essentiality in critical and divergent biological processes. As such, here we aim to discuss recent advances in understanding the diversity of noncanonical ORFs and their roles, as well as detail biologically important examples within the context of the mammalian genome.
Collapse
|
4
|
Unraveling the hidden role of a uORF-encoded peptide as a kinase inhibitor of PKCs. Proc Natl Acad Sci U S A 2021; 118:2018899118. [PMID: 34593629 PMCID: PMC8501901 DOI: 10.1073/pnas.2018899118] [Citation(s) in RCA: 22] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 08/19/2021] [Indexed: 02/01/2023] Open
Abstract
Approximately 40% of human messenger RNAs (mRNAs) contain upstream open reading frames (uORFs) in their 5' untranslated regions. Some of these uORF sequences, thought to attenuate scanning ribosomes or lead to mRNA degradation, were recently shown to be translated, although the function of the encoded peptides remains unknown. Here, we show a uORF-encoded peptide that exhibits kinase inhibitory functions. This uORF, upstream of the protein kinase C-eta (PKC-η) main ORF, encodes a peptide (uPEP2) containing the typical PKC pseudosubstrate motif present in all PKCs that autoinhibits their kinase activity. We show that uPEP2 directly binds to and selectively inhibits the catalytic activity of novel PKCs but not of classical or atypical PKCs. The endogenous deletion of uORF2 or its overexpression in MCF-7 cells revealed that the endogenously translated uPEP2 reduces the protein levels of PKC-η and other novel PKCs and restricts cell proliferation. Functionally, treatment of breast cancer cells with uPEP2 diminished cell survival and their migration and synergized with chemotherapy by interfering with the response to DNA damage. Furthermore, in a xenograft of MDA-MB-231 breast cancer tumor in mice models, uPEP2 suppressed tumor progression, invasion, and metastasis. Tumor histology showed reduced proliferation, enhanced cell death, and lower protein expression levels of novel PKCs along with diminished phosphorylation of PKC substrates. Hence, our study demonstrates that uORFs may encode biologically active peptides beyond their role as translation regulators of their downstream ORFs. Together, we point to a unique function of a uORF-encoded peptide as a kinase inhibitor, pertinent to cancer therapy.
Collapse
|
5
|
Moreira-de-Sá A, Lourenço VS, Canas PM, Cunha RA. Adenosine A 2A Receptors as Biomarkers of Brain Diseases. Front Neurosci 2021; 15:702581. [PMID: 34335174 PMCID: PMC8322233 DOI: 10.3389/fnins.2021.702581] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2021] [Accepted: 06/22/2021] [Indexed: 12/12/2022] Open
Abstract
Extracellular adenosine is produced with increased metabolic activity or stress, acting as a paracrine signal of cellular effort. Adenosine receptors are most abundant in the brain, where adenosine acts through inhibitory A1 receptors to decrease activity/noise and through facilitatory A2A receptors (A2AR) to promote plastic changes in physiological conditions. By bolstering glutamate excitotoxicity and neuroinflammation, A2AR also contribute to synaptic and neuronal damage, as heralded by the neuroprotection afforded by the genetic or pharmacological blockade of A2AR in animal models of ischemia, traumatic brain injury, convulsions/epilepsy, repeated stress or Alzheimer's or Parkinson's diseases. A2AR overfunction is not only necessary for the expression of brain damage but is actually sufficient to trigger brain dysfunction in the absence of brain insults or other disease triggers. Furthermore, A2AR overfunction seems to be an early event in the demise of brain diseases, which involves an increased formation of ATP-derived adenosine and an up-regulation of A2AR. This prompts the novel hypothesis that the evaluation of A2AR density in afflicted brain circuits may become an important biomarker of susceptibility and evolution of brain diseases once faithful PET ligands are optimized. Additional relevant biomarkers would be measuring the extracellular ATP and/or adenosine levels with selective dyes, to identify stressed regions in the brain. A2AR display several polymorphisms in humans and preliminary studies have associated different A2AR polymorphisms with altered morphofunctional brain endpoints associated with neuropsychiatric diseases. This further prompts the interest in exploiting A2AR polymorphic analysis as an ancillary biomarker of susceptibility/evolution of brain diseases.
Collapse
Affiliation(s)
- Ana Moreira-de-Sá
- CNC-Center for Neuroscience and Cell Biology, University of Coimbra, Coimbra, Portugal
| | - Vanessa S Lourenço
- CNC-Center for Neuroscience and Cell Biology, University of Coimbra, Coimbra, Portugal
| | - Paula M Canas
- CNC-Center for Neuroscience and Cell Biology, University of Coimbra, Coimbra, Portugal
| | - Rodrigo A Cunha
- CNC-Center for Neuroscience and Cell Biology, University of Coimbra, Coimbra, Portugal.,Faculty of Medicine, University of Coimbra, Coimbra, Portugal
| |
Collapse
|
6
|
Gagnon M, Savard M, Jacques JF, Bkaily G, Geha S, Roucou X, Gobeil F. Potentiation of B2 receptor signaling by AltB2R, a newly identified alternative protein encoded in the human bradykinin B2 receptor gene. J Biol Chem 2021; 296:100329. [PMID: 33497625 PMCID: PMC7949122 DOI: 10.1016/j.jbc.2021.100329] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2020] [Revised: 01/12/2021] [Accepted: 01/21/2021] [Indexed: 12/27/2022] Open
Abstract
Recent functional and proteomic studies in eukaryotes (www.openprot.org) predict the translation of alternative open reading frames (AltORFs) in mature G-protein-coupled receptor (GPCR) mRNAs, including that of bradykinin B2 receptor (B2R). Our main objective was to determine the implication of a newly discovered AltORF resulting protein, termed AltB2R, in the known signaling properties of B2R using complementary methodological approaches. When ectopically expressed in HeLa cells, AltB2R presented predominant punctate cytoplasmic/perinuclear distribution and apparent cointeraction with B2R at plasma and endosomal/vesicular membranes. The presence of AltB2R increases intracellular [Ca2+] and ERK1/2-MAPK activation (via phosphorylation) following B2R stimulation. Moreover, HEK293A cells expressing mutant B2R lacking concomitant expression of AltB2R displayed significantly decreased maximal responses in agonist-stimulated Gαq-Gαi2/3-protein coupling, IP3 generation, and ERK1/2-MAPK activation as compared with wild-type controls. Conversely, there was no difference in cell-surface density as well as ligand-binding properties of B2R and in efficiencies of cognate agonists at promoting B2R internalization and β-arrestin 2 recruitment. Importantly, both AltB2R and B2R proteins were overexpressed in prostate and breast cancers, compared with their normal counterparts suggesting new associative roles of AltB2R in these diseases. Our study shows that BDKRB2 is a dual-coding gene and identifies AltB2R as a novel positive modulator of some B2R signaling pathways. More broadly, it also supports a new, unexpected alternative proteome for GPCRs, which opens new frontiers in fields of GPCR biology, diseases, and drug discovery.
Collapse
Affiliation(s)
- Maxime Gagnon
- Department of Biochemistry, Université de Sherbrooke, Sherbrooke, Québec, Canada; Institute of Pharmacology, Université de Sherbrooke, Sherbrooke, Québec, Canada
| | - Martin Savard
- Department of Pharmacology & Physiology, Université de Sherbrooke, Sherbrooke, Québec, Canada; Institute of Pharmacology, Université de Sherbrooke, Sherbrooke, Québec, Canada
| | - Jean-François Jacques
- Department of Pharmacology & Physiology, Université de Sherbrooke, Sherbrooke, Québec, Canada
| | - Ghassan Bkaily
- Department of Immunology & Cellular Biology, Université de Sherbrooke, Sherbrooke, Québec, Canada
| | - Sameh Geha
- Department of Pathology, Centre Hospitalier Universitaire de Sherbrooke, Sherbrooke, Québec, Canada
| | - Xavier Roucou
- Department of Biochemistry, Université de Sherbrooke, Sherbrooke, Québec, Canada; Institute of Pharmacology, Université de Sherbrooke, Sherbrooke, Québec, Canada.
| | - Fernand Gobeil
- Department of Pharmacology & Physiology, Université de Sherbrooke, Sherbrooke, Québec, Canada; Institute of Pharmacology, Université de Sherbrooke, Sherbrooke, Québec, Canada.
| |
Collapse
|
7
|
Lopes CR, Lourenço VS, Tomé ÂR, Cunha RA, Canas PM. Use of knockout mice to explore CNS effects of adenosine. Biochem Pharmacol 2020; 187:114367. [PMID: 33333075 DOI: 10.1016/j.bcp.2020.114367] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2020] [Revised: 12/09/2020] [Accepted: 12/09/2020] [Indexed: 12/11/2022]
Abstract
The initial exploration using pharmacological tools of the role of adenosine receptors in the brain, concluded that adenosine released as such acted on A1R to inhibit excitability and glutamate release from principal neurons throughout the brain and that adenosine A2A receptors (A2AR) were striatal-'specific' receptors controlling dopamine D2R. This indicted A1R as potential controllers of neurodegeneration and A2AR of psychiatric conditions. Global knockout of these two receptors questioned the key role of A1R and instead identified extra-striatal A2AR as robust controllers of neurodegeneration. Furthermore, transgenic lines with altered metabolic sources of adenosine revealed a coupling of ATP-derived adenosine to activate A2AR and a role of A1R as a hurdle to initiate neurodegeneration. Additionally, cell-selective knockout of A2AR unveiled the different roles of A2AR in different cell types (neurons/astrocytes) in different portions of the striatal circuits (dorsal versus lateral) and in different brain areas (hippocampus/striatum). Finally, a new transgenic mouse line with deletion of all adenosine receptors seems to indicate a major allostatic rather than homeostatic role of adenosine and may allow isolating P2R-mediated responses to unravel their role in the brain, a goal close to heart of Geoffrey Burnstock, to whom we affectionately dedicate this review.
Collapse
Affiliation(s)
- Cátia R Lopes
- CNC- Center for Neuroscience and Cell Biology, University of Coimbra, 3004-517 Coimbra, Portugal
| | - Vanessa S Lourenço
- CNC- Center for Neuroscience and Cell Biology, University of Coimbra, 3004-517 Coimbra, Portugal
| | - Ângelo R Tomé
- CNC- Center for Neuroscience and Cell Biology, University of Coimbra, 3004-517 Coimbra, Portugal; Department of Life Sciences, Faculty of Sciences and Technology, University of Coimbra, 3000-456 Coimbra, Portugal
| | - Rodrigo A Cunha
- CNC- Center for Neuroscience and Cell Biology, University of Coimbra, 3004-517 Coimbra, Portugal; Faculty of Medicine, University of Coimbra, 3004-504 Coimbra, Portugal.
| | - Paula M Canas
- CNC- Center for Neuroscience and Cell Biology, University of Coimbra, 3004-517 Coimbra, Portugal
| |
Collapse
|
8
|
Chen J, Brunner AD, Cogan JZ, Nuñez JK, Fields AP, Adamson B, Itzhak DN, Li JY, Mann M, Leonetti MD, Weissman JS. Pervasive functional translation of noncanonical human open reading frames. Science 2020; 367:1140-1146. [PMID: 32139545 DOI: 10.1126/science.aay0262] [Citation(s) in RCA: 316] [Impact Index Per Article: 79.0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2019] [Revised: 11/22/2019] [Accepted: 01/13/2020] [Indexed: 12/12/2022]
Abstract
Ribosome profiling has revealed pervasive but largely uncharacterized translation outside of canonical coding sequences (CDSs). In this work, we exploit a systematic CRISPR-based screening strategy to identify hundreds of noncanonical CDSs that are essential for cellular growth and whose disruption elicits specific, robust transcriptomic and phenotypic changes in human cells. Functional characterization of the encoded microproteins reveals distinct cellular localizations, specific protein binding partners, and hundreds of microproteins that are presented by the human leukocyte antigen system. We find multiple microproteins encoded in upstream open reading frames, which form stable complexes with the main, canonical protein encoded on the same messenger RNA, thereby revealing the use of functional bicistronic operons in mammals. Together, our results point to a family of functional human microproteins that play critical and diverse cellular roles.
Collapse
Affiliation(s)
- Jin Chen
- Department of Cellular and Molecular Pharmacology, University of California, San Francisco, CA 94158, USA.,Howard Hughes Medical Institute, University of California, San Francisco, CA 94158, USA
| | - Andreas-David Brunner
- Department of Proteomics and Signal Transduction, Max Planck Institute of Biochemistry, Martinsried 82152, Germany
| | - J Zachery Cogan
- Department of Cellular and Molecular Pharmacology, University of California, San Francisco, CA 94158, USA.,Howard Hughes Medical Institute, University of California, San Francisco, CA 94158, USA
| | - James K Nuñez
- Department of Cellular and Molecular Pharmacology, University of California, San Francisco, CA 94158, USA.,Howard Hughes Medical Institute, University of California, San Francisco, CA 94158, USA
| | - Alexander P Fields
- Department of Cellular and Molecular Pharmacology, University of California, San Francisco, CA 94158, USA.,Howard Hughes Medical Institute, University of California, San Francisco, CA 94158, USA
| | - Britt Adamson
- Department of Cellular and Molecular Pharmacology, University of California, San Francisco, CA 94158, USA.,Howard Hughes Medical Institute, University of California, San Francisco, CA 94158, USA
| | - Daniel N Itzhak
- Cell Atlas Initiative, Chan Zuckerberg Biohub, San Francisco, CA 94158, USA
| | - Jason Y Li
- Cell Atlas Initiative, Chan Zuckerberg Biohub, San Francisco, CA 94158, USA
| | - Matthias Mann
- Department of Proteomics and Signal Transduction, Max Planck Institute of Biochemistry, Martinsried 82152, Germany.,Clinical Proteomics Group, Proteomics Program, Novo Nordisk Foundation Center for Protein Research, University of Copenhagen, Copenhagen 2200, Denmark
| | - Manuel D Leonetti
- Cell Atlas Initiative, Chan Zuckerberg Biohub, San Francisco, CA 94158, USA
| | - Jonathan S Weissman
- Department of Cellular and Molecular Pharmacology, University of California, San Francisco, CA 94158, USA. .,Howard Hughes Medical Institute, University of California, San Francisco, CA 94158, USA
| |
Collapse
|
9
|
Temido-Ferreira M, Coelho JE, Pousinha PA, Lopes LV. Novel Players in the Aging Synapse: Impact on Cognition. J Caffeine Adenosine Res 2019; 9:104-127. [PMID: 31559391 PMCID: PMC6761599 DOI: 10.1089/caff.2019.0013] [Citation(s) in RCA: 33] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
While neuronal loss has long been considered as the main contributor to age-related cognitive decline, these alterations are currently attributed to gradual synaptic dysfunction driven by calcium dyshomeostasis and alterations in ionotropic/metabotropic receptors. Given the key role of the hippocampus in encoding, storage, and retrieval of memory, the morpho- and electrophysiological alterations that occur in the major synapse of this network-the glutamatergic-deserve special attention. We guide you through the hippocampal anatomy, circuitry, and function in physiological context and focus on alterations in neuronal morphology, calcium dynamics, and plasticity induced by aging and Alzheimer's disease (AD). We provide state-of-the art knowledge on glutamatergic transmission and discuss implications of these novel players for intervention. A link between regular consumption of caffeine-an adenosine receptor blocker-to decreased risk of AD in humans is well established, while the mechanisms responsible have only now been uncovered. We review compelling evidence from humans and animal models that implicate adenosine A2A receptors (A2AR) upsurge as a crucial mediator of age-related synaptic dysfunction. The relevance of this mechanism in patients was very recently demonstrated in the form of a significant association of the A2AR-encoding gene with hippocampal volume (synaptic loss) in mild cognitive impairment and AD. Novel pathways implicate A2AR in the control of mGluR5-dependent NMDAR activation and subsequent Ca2+ dysfunction upon aging. The nature of this receptor makes it particularly suited for long-term therapies, as an alternative for regulating aberrant mGluR5/NMDAR signaling in aging and disease, without disrupting their crucial constitutive activity.
Collapse
Affiliation(s)
- Mariana Temido-Ferreira
- Instituto de Medicina Molecular João Lobo Antunes, Faculdade de Medicina, Universidade de Lisboa, Lisboa, Portugal
| | - Joana E. Coelho
- Instituto de Medicina Molecular João Lobo Antunes, Faculdade de Medicina, Universidade de Lisboa, Lisboa, Portugal
| | - Paula A. Pousinha
- Institut de Pharmacologie Moléculaire et Cellulaire (IPMC), CNRS UMR7275, Université Côte d'Azur, Valbonne, France
| | - Luísa V. Lopes
- Instituto de Medicina Molecular João Lobo Antunes, Faculdade de Medicina, Universidade de Lisboa, Lisboa, Portugal
| |
Collapse
|
10
|
Huin V, Dhaenens CM, Homa M, Carvalho K, Buée L, Sablonnière B. Neurogenetics of the Human Adenosine Receptor Genes: Genetic Structures and Involvement in Brain Diseases. J Caffeine Adenosine Res 2019. [DOI: 10.1089/caff.2019.0011] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Affiliation(s)
- Vincent Huin
- University of Lille, INSERM, CHU Lille, UMR-S 1172-JPArc–Centre de Recherche Jean-Pierre AUBERT Neurosciences et Cancer, Lille, France
- CHU Lille, Institut de Biochimie et Biologie moléculaire, Centre de Biologie Pathologie et Génétique, Lille, France
| | - Claire-Marie Dhaenens
- University of Lille, INSERM, CHU Lille, UMR-S 1172-JPArc–Centre de Recherche Jean-Pierre AUBERT Neurosciences et Cancer, Lille, France
- CHU Lille, Institut de Biochimie et Biologie moléculaire, Centre de Biologie Pathologie et Génétique, Lille, France
| | - Mégane Homa
- University of Lille, INSERM, CHU Lille, UMR-S 1172-JPArc–Centre de Recherche Jean-Pierre AUBERT Neurosciences et Cancer, Lille, France
| | - Kévin Carvalho
- University of Lille, INSERM, CHU Lille, UMR-S 1172-JPArc–Centre de Recherche Jean-Pierre AUBERT Neurosciences et Cancer, Lille, France
| | - Luc Buée
- University of Lille, INSERM, CHU Lille, UMR-S 1172-JPArc–Centre de Recherche Jean-Pierre AUBERT Neurosciences et Cancer, Lille, France
| | - Bernard Sablonnière
- University of Lille, INSERM, CHU Lille, UMR-S 1172-JPArc–Centre de Recherche Jean-Pierre AUBERT Neurosciences et Cancer, Lille, France
- CHU Lille, Institut de Biochimie et Biologie moléculaire, Centre de Biologie Pathologie et Génétique, Lille, France
| |
Collapse
|
11
|
Zhong VW, Kuang A, Danning RD, Kraft P, van Dam RM, Chasman DI, Cornelis MC. A genome-wide association study of bitter and sweet beverage consumption. Hum Mol Genet 2019; 28:2449-2457. [PMID: 31046077 PMCID: PMC6606847 DOI: 10.1093/hmg/ddz061] [Citation(s) in RCA: 98] [Impact Index Per Article: 19.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2018] [Revised: 07/14/2018] [Accepted: 08/09/2018] [Indexed: 01/07/2023] Open
Abstract
Except for drinking water, most beverages taste bitter or sweet. Taste perception and preferences are heritable and determinants of beverage choice and consumption. Consumption of several bitter- and sweet-tasting beverages has been implicated in development of major chronic diseases. We performed a genome-wide association study (GWAS) of self-reported bitter and sweet beverage consumption among ~370 000 participants of European ancestry, using a two-staged analysis design. Bitter beverages included coffee, tea, grapefruit juice, red wine, liquor and beer. Sweet beverages included artificially and sugar sweetened beverages (SSBs) and non-grapefruit juices. Five loci associated with total bitter beverage consumption were replicated (in/near GCKR, ABCG2, AHR, POR and CYP1A1/2). No locus was replicated for total sweet beverage consumption. Sub-phenotype analyses targeting the alcohol, caffeine and sweetener components of beverages yielded additional loci: (i) four loci for bitter alcoholic beverages (GCKR, KLB, ADH1B and AGBL2); (ii) five loci for bitter non-alcoholic beverages (ANXA9, AHR, POR, CYP1A1/2 and CSDC2); (iii) 10 loci for coffee; six novel loci (SEC16B, TMEM18, OR8U8, AKAP6, MC4R and SPECC1L-ADORA2A); (iv) FTO for SSBs. Of these 17 replicated loci, 12 have been associated with total alcohol consumption, coffee consumption, plasma caffeine metabolites or BMI in previous GWAS; none was involved in known sweet and bitter taste transduction pathways. Our study suggests that genetic variants related to alcohol consumption, coffee consumption and obesity were primary genetic determinants of bitter and sweet beverage consumption. Whether genetic variants related to taste perception are associated with beverage consumption remains to be determined.
Collapse
Affiliation(s)
- Victor W Zhong
- Department of Preventive Medicine, Northwestern University Feinberg School of Medicine, Chicago, IL, USA
| | - Alan Kuang
- Department of Preventive Medicine, Northwestern University Feinberg School of Medicine, Chicago, IL, USA
| | - Rebecca D Danning
- Division of Preventive Medicine, Brigham and Women's Hospital, Boston, MA, USA
| | - Peter Kraft
- Department of Epidemiology, Harvard School of Public Health and Department of Biostatistics, Boston, MA, USA
| | - Rob M van Dam
- Saw Swee Hock School of Public Health, National University of Singapore, Singapore
- Department of Medicine, Yong Loo Lin School of Medicine, National University of Singapore, Singapore
| | - Daniel I Chasman
- Division of Preventive Medicine, Brigham and Women's Hospital, Boston, MA, USA
- Department of Medicine, Harvard Medical School, Boston, MA, USA
| | - Marilyn C Cornelis
- Department of Preventive Medicine, Northwestern University Feinberg School of Medicine, Chicago, IL, USA
| |
Collapse
|
12
|
Nedeljkovic N. Complex regulation of ecto-5'-nucleotidase/CD73 and A 2AR-mediated adenosine signaling at neurovascular unit: A link between acute and chronic neuroinflammation. Pharmacol Res 2019; 144:99-115. [PMID: 30954629 DOI: 10.1016/j.phrs.2019.04.007] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/29/2018] [Revised: 04/01/2019] [Accepted: 04/03/2019] [Indexed: 12/20/2022]
Abstract
The review summarizes available data regarding the complex regulation of CD73 at the neurovascular unit (NVU) during neuroinflammation. Based on available data we propose the biphasic pattern of CD73 regulation at NVU, with an early attenuation and a postponed up-regulation of CD73 activity. Transient attenuation of CD73 activity on leukocyte/vascular endothelium and leukocyte/astrocyte surface, required for the initiation of a neuroinflammatory response, may be effectuated either by catalytic inhibition of CD73 and/or by shedding of the CD73 molecule from the cell surface, while postponed induction of CD73 is effectuated by transcriptional up-regulation of Nt5e and posttranslational modifications. Neuroinflammatory conditions are also associated with significant enhancement and gain-of-function of A2AR-mediated adenosine signaling. However, in contrast to the temporary prevalence of A2AR over A1R signaling during an acute inflammatory response, prolonged induction of A2AR and resulting perpetual CD73/A2AR coupling may be a contributing factors in the transition between acute and chronic neuroinflammation. Thus, pharmacological targeting of the CD73/A2AR axis may attenuate inflammatory response and ameliorate neurological deficits in chronic neuroinflammatory conditions.
Collapse
Affiliation(s)
- Nadezda Nedeljkovic
- Department of General Physiology and Biophysics, Faculty of Biology University of Belgrade, Studentski trg 3, Belgrade 11001, Serbia.
| |
Collapse
|
13
|
Lorenzo-Orts L, Witthoeft J, Deforges J, Martinez J, Loubéry S, Placzek A, Poirier Y, Hothorn LA, Jaillais Y, Hothorn M. Concerted expression of a cell cycle regulator and a metabolic enzyme from a bicistronic transcript in plants. NATURE PLANTS 2019; 5:184-193. [PMID: 30737513 DOI: 10.1038/s41477-019-0358-3] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/10/2018] [Accepted: 01/04/2019] [Indexed: 05/15/2023]
Abstract
Eukaryotic mRNAs frequently contain upstream open reading frames (uORFs), encoding small peptides that may control translation of the main ORF (mORF). Here, we report the characterization of a distinct bicistronic transcript in Arabidopsis. We analysed loss-of-function phenotypes of the inorganic polyphosphatase TRIPHOSPHATE TUNNEL METALLOENZYME 3 (AtTTM3), and found that catalytically inactive versions of the enzyme could fully complement embryo and growth-related phenotypes. We could rationalize these puzzling findings by characterizing a uORF in the AtTTM3 locus encoding CELL DIVISION CYCLE PROTEIN 26 (CDC26), an orthologue of the cell cycle regulator. We demonstrate that AtCDC26 is part of the plant anaphase promoting complex/cyclosome (APC/C), regulates accumulation of APC/C target proteins and controls cell division, growth and embryo development. AtCDC26 and AtTTM3 are translated from a single transcript conserved across the plant lineage. While there is no apparent biochemical connection between the two gene products, AtTTM3 coordinates AtCDC26 translation by recruiting the transcript into polysomes. Our work highlights that uORFs may encode functional proteins in plant genomes.
Collapse
Affiliation(s)
- Laura Lorenzo-Orts
- Structural Plant Biology Laboratory, Department of Botany and Plant Biology, University of Geneva, Geneva, Switzerland.
| | - Janika Witthoeft
- Friedrich Miescher Laboratory of the Max Planck Society, Tübingen, Germany
| | - Jules Deforges
- Department of Plant Molecular Biology, University of Lausanne, Lausanne, Switzerland
| | - Jacobo Martinez
- Structural Plant Biology Laboratory, Department of Botany and Plant Biology, University of Geneva, Geneva, Switzerland
- Friedrich Miescher Laboratory of the Max Planck Society, Tübingen, Germany
| | - Sylvain Loubéry
- Department of Botany and Plant Biology, University of Geneva, Geneva, Switzerland
| | - Aleksandra Placzek
- Friedrich Miescher Laboratory of the Max Planck Society, Tübingen, Germany
- Max Planck Institute for Biology of Ageing, Cologne, Germany
| | - Yves Poirier
- Department of Plant Molecular Biology, University of Lausanne, Lausanne, Switzerland
| | - Ludwig A Hothorn
- Institute of Biostatistics, Leibniz University, Hannover, Germany
| | - Yvon Jaillais
- Laboratoire Reproduction et Développement des Plantes, Université de Lyon, ENS de Lyon, UCB Lyon 1, CNRS, INRA, Lyon, France
| | - Michael Hothorn
- Structural Plant Biology Laboratory, Department of Botany and Plant Biology, University of Geneva, Geneva, Switzerland.
- Friedrich Miescher Laboratory of the Max Planck Society, Tübingen, Germany.
| |
Collapse
|
14
|
Brunet MA, Levesque SA, Hunting DJ, Cohen AA, Roucou X. Recognition of the polycistronic nature of human genes is critical to understanding the genotype-phenotype relationship. Genome Res 2018; 28:609-624. [PMID: 29626081 PMCID: PMC5932603 DOI: 10.1101/gr.230938.117] [Citation(s) in RCA: 42] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2017] [Accepted: 03/27/2018] [Indexed: 12/12/2022]
Abstract
Technological advances promise unprecedented opportunities for whole exome sequencing and proteomic analyses of populations. Currently, data from genome and exome sequencing or proteomic studies are searched against reference genome annotations. This provides the foundation for research and clinical screening for genetic causes of pathologies. However, current genome annotations substantially underestimate the proteomic information encoded within a gene. Numerous studies have now demonstrated the expression and function of alternative (mainly small, sometimes overlapping) ORFs within mature gene transcripts. This has important consequences for the correlation of phenotypes and genotypes. Most alternative ORFs are not yet annotated because of a lack of evidence, and this absence from databases precludes their detection by standard proteomic methods, such as mass spectrometry. Here, we demonstrate how current approaches tend to overlook alternative ORFs, hindering the discovery of new genetic drivers and fundamental research. We discuss available tools and techniques to improve identification of proteins from alternative ORFs and finally suggest a novel annotation system to permit a more complete representation of the transcriptomic and proteomic information contained within a gene. Given the crucial challenge of distinguishing functional ORFs from random ones, the suggested pipeline emphasizes both experimental data and conservation signatures. The addition of alternative ORFs in databases will render identification less serendipitous and advance the pace of research and genomic knowledge. This review highlights the urgent medical and research need to incorporate alternative ORFs in current genome annotations and thus permit their inclusion in hypotheses and models, which relate phenotypes and genotypes.
Collapse
Affiliation(s)
- Marie A Brunet
- Biochemistry Department, Université de Sherbrooke, Quebec J1E 4K8, Canada.,Groupe de recherche PRIMUS, Department of Family and Emergency Medicine, Quebec J1H 5N4, Canada.,PROTEO, Quebec Network for Research on Protein Function, Structure, and Engineering, Université Laval, Quebec G1V 0A6, Canada
| | - Sébastien A Levesque
- Pediatric Department, Centre Hospitalier de l'Université de Sherbrooke, Quebec J1H 5N4, Canada
| | - Darel J Hunting
- Department of Nuclear Medicine & Radiobiology, Université de Sherbrooke, Quebec J1H 5N4, Canada
| | - Alan A Cohen
- Groupe de recherche PRIMUS, Department of Family and Emergency Medicine, Quebec J1H 5N4, Canada
| | - Xavier Roucou
- Biochemistry Department, Université de Sherbrooke, Quebec J1E 4K8, Canada.,PROTEO, Quebec Network for Research on Protein Function, Structure, and Engineering, Université Laval, Quebec G1V 0A6, Canada
| |
Collapse
|
15
|
Rajasundaram S. Adenosine A2A Receptor Signaling in the Immunopathogenesis of Experimental Autoimmune Encephalomyelitis. Front Immunol 2018; 9:402. [PMID: 29559972 PMCID: PMC5845642 DOI: 10.3389/fimmu.2018.00402] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2017] [Accepted: 02/13/2018] [Indexed: 12/19/2022] Open
Abstract
Our increasing appreciation of adenosine as an endogenous signaling molecule that terminates inflammation has generated excitement regarding the potential to target adenosine receptors (ARs) in the treatment of multiple sclerosis (MS), a disease of chronic neuroinflammation. Of the four G protein-coupled ARs, A2ARs are the principal mediator of adenosine’s anti-inflammatory effects and accordingly, there is a growing body of evidence surrounding the role of A2ARs in experimental autoimmune encephalomyelitis (EAE), the dominant animal model of MS. Such evidence points to a complex, often paradoxical role for A2ARs in the immunopathogenesis of EAE, where they have the ability to both exacerbate and alleviate disease severity. This review seeks to interpret these paradoxical findings and evaluate the therapeutic promise of A2ARs. In essence, the complexities of A2AR signaling arise from two properties. Firstly, A2AR signaling downregulates the inflammatory potential of TH lymphocytes whilst simultaneously facilitating the recruitment of these cells into the CNS. Secondly, A2AR expression by myeloid cells – infiltrating macrophages and CNS-resident microglia – has the capacity to promote both tissue injury and repair in chronic neuroinflammation. Consequently, the therapeutic potential of targeting A2ARs is greatly undermined by the risk of collateral tissue damage in the periphery and/or CNS.
Collapse
|
16
|
Samandi S, Roy AV, Delcourt V, Lucier JF, Gagnon J, Beaudoin MC, Vanderperre B, Breton MA, Motard J, Jacques JF, Brunelle M, Gagnon-Arsenault I, Fournier I, Ouangraoua A, Hunting DJ, Cohen AA, Landry CR, Scott MS, Roucou X. Deep transcriptome annotation enables the discovery and functional characterization of cryptic small proteins. eLife 2017; 6:27860. [PMID: 29083303 PMCID: PMC5703645 DOI: 10.7554/elife.27860] [Citation(s) in RCA: 78] [Impact Index Per Article: 11.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2017] [Accepted: 10/29/2017] [Indexed: 01/10/2023] Open
Abstract
Recent functional, proteomic and ribosome profiling studies in eukaryotes have concurrently demonstrated the translation of alternative open-reading frames (altORFs) in addition to annotated protein coding sequences (CDSs). We show that a large number of small proteins could in fact be coded by these altORFs. The putative alternative proteins translated from altORFs have orthologs in many species and contain functional domains. Evolutionary analyses indicate that altORFs often show more extreme conservation patterns than their CDSs. Thousands of alternative proteins are detected in proteomic datasets by reanalysis using a database containing predicted alternative proteins. This is illustrated with specific examples, including altMiD51, a 70 amino acid mitochondrial fission-promoting protein encoded in MiD51/Mief1/SMCR7L, a gene encoding an annotated protein promoting mitochondrial fission. Our results suggest that many genes are multicoding genes and code for a large protein and one or several small proteins. Proteins are often referred to as the workhorses of the cell, and these molecules affect all aspects of human health and disease. Thus, deciphering the entire set of proteins made by an organism is often an important challenge for biologists. Genes contain the instructions to make a protein, but first they must be copied into a molecule called an mRNA. The part of the mRNA that actually codes for the protein is referred to as an open reading frame (or ORF for short). For many years, most scientists assumed that, except for in bacteria, each mature mRNA in an organism has just a single functional ORF, and that this was generally the longest possible ORF within the mRNA. Many also assumed that RNAs copied from genes that had been labelled as “non-coding” or as “pseudogenes” did not contain functional ORFs. Yet, new ORFs encoding small proteins were recently discovered in RNAs (or parts of RNA) that had previously been annotated as non-coding. Working out what these small proteins actually do will require scientists being able to find more of these overlooked ORFs. The RNAs produced by many organisms – from humans and mice to fruit flies and yeast – have been catalogued and the data stored in publicly accessible databases. Samandi, Roy et al. have now taken a fresh look at the data for nine different organisms, and identified several thousand examples of possibly overlooked ORFs, which they refer to as “alternative ORFs”. This included more than 180,000 from humans. Further analysis of other datasets that captured details of the proteins actually produced in human cells uncovered thousands of small proteins encoded by the predicted alternative ORFs. Many of the so-called alternative proteins also resembled parts of other proteins that have a known activity or function. Lastly, Samandi, Roy et al. focused on two alternative proteins and showed that they both might affect the activity of the proteins coded within the main ORF in their respective genes. These findings reveal new details about the different proteins encoded within the genes of humans and other organisms, including that many mRNAs encode more that one protein. The implications and applications of this research could be far-reaching, and may help scientists to better understand how genes work in both health and disease.
Collapse
Affiliation(s)
- Sondos Samandi
- Department of Biochemistry, Université de Sherbrooke, Sherbrooke, Canada.,PROTEO, Québec Network for Research on Protein Function, Structure and Engineering, Québec, Canada
| | - Annie V Roy
- Department of Biochemistry, Université de Sherbrooke, Sherbrooke, Canada.,PROTEO, Québec Network for Research on Protein Function, Structure and Engineering, Québec, Canada
| | - Vivian Delcourt
- Department of Biochemistry, Université de Sherbrooke, Sherbrooke, Canada.,PROTEO, Québec Network for Research on Protein Function, Structure and Engineering, Québec, Canada.,INSERM U1192, Laboratoire Protéomique, Réponse Inflammatoire & Spectrométrie de Masse (PRISM) F-59000 Lille, Université de Lille, Lille, France
| | - Jean-François Lucier
- Department of Biology, Université de Sherbrooke, Québec, Canada.,Center for Scientific computing, Information Technologies Services,, Université de Sherbrooke, Québec, Canada
| | - Jules Gagnon
- Department of Biology, Université de Sherbrooke, Québec, Canada.,Center for Scientific computing, Information Technologies Services,, Université de Sherbrooke, Québec, Canada
| | - Maxime C Beaudoin
- Department of Biochemistry, Université de Sherbrooke, Sherbrooke, Canada.,PROTEO, Québec Network for Research on Protein Function, Structure and Engineering, Québec, Canada
| | - Benoît Vanderperre
- Department of Biochemistry, Université de Sherbrooke, Sherbrooke, Canada
| | - Marc-André Breton
- Department of Biochemistry, Université de Sherbrooke, Sherbrooke, Canada
| | - Julie Motard
- Department of Biochemistry, Université de Sherbrooke, Sherbrooke, Canada.,PROTEO, Québec Network for Research on Protein Function, Structure and Engineering, Québec, Canada
| | - Jean-François Jacques
- Department of Biochemistry, Université de Sherbrooke, Sherbrooke, Canada.,PROTEO, Québec Network for Research on Protein Function, Structure and Engineering, Québec, Canada
| | - Mylène Brunelle
- Department of Biochemistry, Université de Sherbrooke, Sherbrooke, Canada.,PROTEO, Québec Network for Research on Protein Function, Structure and Engineering, Québec, Canada
| | - Isabelle Gagnon-Arsenault
- PROTEO, Québec Network for Research on Protein Function, Structure and Engineering, Québec, Canada.,Département de biochimie, microbiologie et bioinformatique, Université Laval, Québec, Canada.,IBIS, Université Laval, Québec, Canada
| | - Isabelle Fournier
- INSERM U1192, Laboratoire Protéomique, Réponse Inflammatoire & Spectrométrie de Masse (PRISM) F-59000 Lille, Université de Lille, Lille, France
| | - Aida Ouangraoua
- Department of Computer Science, Université de Sherbrooke, Québec, Canada
| | - Darel J Hunting
- Department of Nuclear Medicine and Radiobiology, Université de Sherbrooke, Québec, Canada
| | - Alan A Cohen
- Department of Family Medicine, Université de Sherbrooke, Québec, Canada
| | - Christian R Landry
- PROTEO, Québec Network for Research on Protein Function, Structure and Engineering, Québec, Canada.,Département de biochimie, microbiologie et bioinformatique, Université Laval, Québec, Canada.,IBIS, Université Laval, Québec, Canada
| | - Michelle S Scott
- Department of Biochemistry, Université de Sherbrooke, Sherbrooke, Canada
| | - Xavier Roucou
- Department of Biochemistry, Université de Sherbrooke, Sherbrooke, Canada.,PROTEO, Québec Network for Research on Protein Function, Structure and Engineering, Québec, Canada
| |
Collapse
|
17
|
Delcourt V, Staskevicius A, Salzet M, Fournier I, Roucou X. Small Proteins Encoded by Unannotated ORFs are Rising Stars of the Proteome, Confirming Shortcomings in Genome Annotations and Current Vision of an mRNA. Proteomics 2017. [DOI: 10.1002/pmic.201700058] [Citation(s) in RCA: 43] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Affiliation(s)
- Vivian Delcourt
- Department of Biochemistry; Université de Sherbrooke; Quebec Canada
- Univ. Lille, INSERM U1192, Laboratoire Protéomique; Réponse Inflammatoire & Spectrométrie de Masse (PRISM); Lille France
- PROTEO, Quebec Network for Research on Protein Function; Structure, and Engineering; Quebec Canada
| | | | - Michel Salzet
- Univ. Lille, INSERM U1192, Laboratoire Protéomique; Réponse Inflammatoire & Spectrométrie de Masse (PRISM); Lille France
| | - Isabelle Fournier
- Univ. Lille, INSERM U1192, Laboratoire Protéomique; Réponse Inflammatoire & Spectrométrie de Masse (PRISM); Lille France
| | - Xavier Roucou
- Department of Biochemistry; Université de Sherbrooke; Quebec Canada
- PROTEO, Quebec Network for Research on Protein Function; Structure, and Engineering; Quebec Canada
| |
Collapse
|
18
|
Sun Y, Li W. Activity-guided isolation and structural identification of immunomodulating substances from Pleurotus eryngii byproducts. Int Immunopharmacol 2017; 51:82-90. [DOI: 10.1016/j.intimp.2017.08.005] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2017] [Revised: 08/07/2017] [Accepted: 08/08/2017] [Indexed: 11/26/2022]
|
19
|
Cunha RA. How does adenosine control neuronal dysfunction and neurodegeneration? J Neurochem 2016; 139:1019-1055. [PMID: 27365148 DOI: 10.1111/jnc.13724] [Citation(s) in RCA: 301] [Impact Index Per Article: 37.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2016] [Revised: 05/23/2016] [Accepted: 06/23/2016] [Indexed: 12/11/2022]
Abstract
The adenosine modulation system mostly operates through inhibitory A1 (A1 R) and facilitatory A2A receptors (A2A R) in the brain. The activity-dependent release of adenosine acts as a brake of excitatory transmission through A1 R, which are enriched in glutamatergic terminals. Adenosine sharpens salience of information encoding in neuronal circuits: high-frequency stimulation triggers ATP release in the 'activated' synapse, which is locally converted by ecto-nucleotidases into adenosine to selectively activate A2A R; A2A R switch off A1 R and CB1 receptors, bolster glutamate release and NMDA receptors to assist increasing synaptic plasticity in the 'activated' synapse; the parallel engagement of the astrocytic syncytium releases adenosine further inhibiting neighboring synapses, thus sharpening the encoded plastic change. Brain insults trigger a large outflow of adenosine and ATP, as a danger signal. A1 R are a hurdle for damage initiation, but they desensitize upon prolonged activation. However, if the insult is near-threshold and/or of short-duration, A1 R trigger preconditioning, which may limit the spread of damage. Brain insults also up-regulate A2A R, probably to bolster adaptive changes, but this heightens brain damage since A2A R blockade affords neuroprotection in models of epilepsy, depression, Alzheimer's, or Parkinson's disease. This initially involves a control of synaptotoxicity by neuronal A2A R, whereas astrocytic and microglia A2A R might control the spread of damage. The A2A R signaling mechanisms are largely unknown since A2A R are pleiotropic, coupling to different G proteins and non-canonical pathways to control the viability of glutamatergic synapses, neuroinflammation, mitochondria function, and cytoskeleton dynamics. Thus, simultaneously bolstering A1 R preconditioning and preventing excessive A2A R function might afford maximal neuroprotection. The main physiological role of the adenosine modulation system is to sharp the salience of information encoding through a combined action of adenosine A2A receptors (A2A R) in the synapse undergoing an alteration of synaptic efficiency with an increased inhibitory action of A1 R in all surrounding synapses. Brain insults trigger an up-regulation of A2A R in an attempt to bolster adaptive plasticity together with adenosine release and A1 R desensitization; this favors synaptotocity (increased A2A R) and decreases the hurdle to undergo degeneration (decreased A1 R). Maximal neuroprotection is expected to result from a combined A2A R blockade and increased A1 R activation. This article is part of a mini review series: "Synaptic Function and Dysfunction in Brain Diseases".
Collapse
Affiliation(s)
- Rodrigo A Cunha
- CNC-Center for Neuroscience and Cell Biology, University of Coimbra, Coimbra, Portugal.,FMUC-Faculty of Medicine, University of Coimbra, Coimbra, Portugal
| |
Collapse
|
20
|
Sheshukova EV, Shindyapina AV, Komarova TV, Dorokhov YL. “Matreshka” genes with alternative reading frames. RUSS J GENET+ 2016. [DOI: 10.1134/s1022795416020149] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
|
21
|
Mouilleron H, Delcourt V, Roucou X. Death of a dogma: eukaryotic mRNAs can code for more than one protein. Nucleic Acids Res 2016; 44:14-23. [PMID: 26578573 PMCID: PMC4705651 DOI: 10.1093/nar/gkv1218] [Citation(s) in RCA: 63] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2015] [Revised: 10/26/2015] [Accepted: 10/28/2015] [Indexed: 12/13/2022] Open
Abstract
mRNAs carry the genetic information that is translated by ribosomes. The traditional view of a mature eukaryotic mRNA is a molecule with three main regions, the 5' UTR, the protein coding open reading frame (ORF) or coding sequence (CDS), and the 3' UTR. This concept assumes that ribosomes translate one ORF only, generally the longest one, and produce one protein. As a result, in the early days of genomics and bioinformatics, one CDS was associated with each protein-coding gene. This fundamental concept of a single CDS is being challenged by increasing experimental evidence indicating that annotated proteins are not the only proteins translated from mRNAs. In particular, mass spectrometry (MS)-based proteomics and ribosome profiling have detected productive translation of alternative open reading frames. In several cases, the alternative and annotated proteins interact. Thus, the expression of two or more proteins translated from the same mRNA may offer a mechanism to ensure the co-expression of proteins which have functional interactions. Translational mechanisms already described in eukaryotic cells indicate that the cellular machinery is able to translate different CDSs from a single viral or cellular mRNA. In addition to summarizing data showing that the protein coding potential of eukaryotic mRNAs has been underestimated, this review aims to challenge the single translated CDS dogma.
Collapse
Affiliation(s)
- Hélène Mouilleron
- Department of biochemistry, Université de Sherbrooke, Sherbrooke, Quebec J1E 4K8, Canada PROTEO, Quebec Network for Research on Protein Function, Structure, and Engineering, Quebec, Canada
| | - Vivian Delcourt
- Department of biochemistry, Université de Sherbrooke, Sherbrooke, Quebec J1E 4K8, Canada PROTEO, Quebec Network for Research on Protein Function, Structure, and Engineering, Quebec, Canada Inserm U-1192, Laboratoire de Protéomique, Réponse Inflammatoire, Spectrométrie de Masse (PRISM), Université de Lille 1, Cité Scientifique, 59655 Villeneuve D'Ascq, France
| | - Xavier Roucou
- Department of biochemistry, Université de Sherbrooke, Sherbrooke, Quebec J1E 4K8, Canada PROTEO, Quebec Network for Research on Protein Function, Structure, and Engineering, Quebec, Canada
| |
Collapse
|
22
|
Zhao L, Liu YW, Yang T, Gan L, Yang N, Dai SS, He F. The mutual regulation between miR-214 and A2AR signaling plays an important role in inflammatory response. Cell Signal 2015; 27:2026-34. [DOI: 10.1016/j.cellsig.2015.07.007] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2015] [Revised: 07/06/2015] [Accepted: 07/10/2015] [Indexed: 11/15/2022]
|
23
|
Chen JF, Lee CF, Chern Y. Adenosine receptor neurobiology: overview. INTERNATIONAL REVIEW OF NEUROBIOLOGY 2015; 119:1-49. [PMID: 25175959 DOI: 10.1016/b978-0-12-801022-8.00001-5] [Citation(s) in RCA: 90] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Adenosine is a naturally occurring nucleoside that is distributed ubiquitously throughout the body as a metabolic intermediary. In the brain, adenosine functions as an important upstream neuromodulator of a broad spectrum of neurotransmitters, receptors, and signaling pathways. By acting through four G-protein-coupled receptors, adenosine contributes critically to homeostasis and neuromodulatory control of a variety of normal and abnormal brain functions, ranging from synaptic plasticity, to cognition, to sleep, to motor activity to neuroinflammation, and cell death. This review begun with an overview of the gene and genome structure and the expression pattern of adenosine receptors (ARs). We feature several new developments over the past decade in our understanding of AR functions in the brain, with special focus on the identification and characterization of canonical and noncanonical signaling pathways of ARs. We provide an update on functional insights from complementary genetic-knockout and pharmacological studies on the AR control of various brain functions. We also highlight several novel and recent developments of AR neurobiology, including (i) recent breakthrough in high resolution of three-dimension structure of adenosine A2A receptors (A2ARs) in several functional status, (ii) receptor-receptor heterodimerization, (iii) AR function in glial cells, and (iv) the druggability of AR. We concluded the review with the contention that these new developments extend and strengthen the support for A1 and A2ARs in brain as therapeutic targets for neurologic and psychiatric diseases.
Collapse
Affiliation(s)
- Jiang-Fan Chen
- Department of Neurology, Boston University School of Medicine, Boston, Massachusetts, USA.
| | - Chien-fei Lee
- Division of Neuroscience, Institute of Biomedical Sciences, Academia Sinica, Taipei, Taiwan
| | - Yijuang Chern
- Division of Neuroscience, Institute of Biomedical Sciences, Academia Sinica, Taipei, Taiwan
| |
Collapse
|
24
|
Sundar R, Soong R, Cho BC, Brahmer JR, Soo RA. Immunotherapy in the treatment of non-small cell lung cancer. Lung Cancer 2014; 85:101-9. [PMID: 24880938 PMCID: PMC4332778 DOI: 10.1016/j.lungcan.2014.05.005] [Citation(s) in RCA: 79] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2014] [Accepted: 05/07/2014] [Indexed: 12/12/2022]
Abstract
Advances in the understanding of the role of the immune system in tumor immunosurveillance have resulted in the recognition that tumors can evade immune destruction via the dysregulation of co-inhibitory or checkpoint signals. This has led to the development of a generation immunotherapeutic agents targeting the immune checkpoint pathway. Recent early phase studies of immune checkpoint modulators, such as CTLA-4, PD-1 and PD-L1 inhibitors in NSCLC have reported promising results with prolonged clinical responses and tolerable toxicity. This article provides an overview of co-stimulatory and inhibitory molecules that regulate the immune response to tumors, recent therapies that have been developed to exploit these interactions and the role of predictive biomarkers in treatment selection.
Collapse
Affiliation(s)
- Raghav Sundar
- Department of Haematology-Oncology, National University Cancer Institute, National University Health System, Singapore
| | - Richie Soong
- Cancer Science Institute of Singapore, National University of Singapore, Singapore; Department of Pathology, National University Health System, Singapore
| | - Byoung-Chul Cho
- Division of Medical Oncology, Yonsei Cancer Center, Seoul, South Korea
| | - Julie R Brahmer
- Department of Oncology, The Sidney Kimmel Comprehensive Cancer Center, Johns Hopkins, Baltimore, MD, United States
| | - Ross A Soo
- Department of Haematology-Oncology, National University Cancer Institute, National University Health System, Singapore; Cancer Science Institute of Singapore, National University of Singapore, Singapore; Department of Surgery, University of Western Australia, Australia.
| |
Collapse
|