No G-Quadruplex Structures in the DNA of Parvovirus B19: Experimental Evidence versus Bioinformatic Predictions
Parvovirus B19 (B19V), an ssDNA virus in the family Parvoviridae, is a human pathogenic virus, responsible for a wide range of clinical manifestations, still in need of effective and specific antivirals. DNA structures, including G-quadruplex (G4), have been recognised as relevant functional feature...
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MDPI AG
2020-08-01
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| Series: | Viruses |
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| Online Access: | https://www.mdpi.com/1999-4915/12/9/935 |
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| author | Gloria Bua Daniele Tedesco Ilaria Conti Alessandro Reggiani Manuela Bartolini Giorgio Gallinella |
| author_facet | Gloria Bua Daniele Tedesco Ilaria Conti Alessandro Reggiani Manuela Bartolini Giorgio Gallinella |
| author_sort | Gloria Bua |
| collection | DOAJ |
| description | Parvovirus B19 (B19V), an ssDNA virus in the family Parvoviridae, is a human pathogenic virus, responsible for a wide range of clinical manifestations, still in need of effective and specific antivirals. DNA structures, including G-quadruplex (G4), have been recognised as relevant functional features in viral genomes, and small-molecule ligands binding to these structures are promising antiviral compounds. Bioinformatic tools predict the presence of potential G4 forming sequences (PQSs) in the genome of B19V, raising interest as targets for antiviral strategies. Predictions locate PQSs in the genomic terminal regions, in proximity to replicative origins. The actual propensity of these PQSs to form G4 structures was investigated by circular dichroism spectroscopic analysis on synthetic oligonucleotides of corresponding sequences. No signature of G4 structures was detected, and the interaction with the G4 ligand BRACO-19 (<i>N</i>,<i>N</i>′-(9-{[4-(dimethylamino)phenyl]amino}acridine-3,6-diyl)bis(3-pyrrolidin-1-ylpropanamide) did not appear consistent with the stabilisation of G4 structures. Any potential role of PQSs in the viral lifecycle was then assessed in an in vitro infection model system, by evaluating any variation in replication or expression of B19V in the presence of the G4 ligands BRACO-19 and pyridostatin. Neither showed a significant inhibitory activity on B19V replication or expression. Experimental challenge did not support bioinformatic predictions. The terminal regions of B19V are characterised by relevant sequence and symmetry constraints, which are functional to viral replication. Our experiments suggest that these impose a stringent requirement prevailing over the propensity of forming actual G4 structures. |
| first_indexed | 2024-03-10T16:49:59Z |
| format | Article |
| id | doaj.art-9a138ad2406c4fd097318c0b221a5283 |
| institution | Directory Open Access Journal |
| issn | 1999-4915 |
| language | English |
| last_indexed | 2024-03-10T16:49:59Z |
| publishDate | 2020-08-01 |
| publisher | MDPI AG |
| record_format | Article |
| series | Viruses |
| spelling | doaj.art-9a138ad2406c4fd097318c0b221a52832023-11-20T11:20:46ZengMDPI AGViruses1999-49152020-08-0112993510.3390/v12090935No G-Quadruplex Structures in the DNA of Parvovirus B19: Experimental Evidence versus Bioinformatic PredictionsGloria Bua0Daniele Tedesco1Ilaria Conti2Alessandro Reggiani3Manuela Bartolini4Giorgio Gallinella5Department of Pharmacy and Biotechnology, University of Bologna, 40126 Bologna, ItalyDepartment of Pharmacy and Biotechnology, University of Bologna, 40126 Bologna, ItalyDepartment of Pharmacy and Biotechnology, University of Bologna, 40126 Bologna, ItalyDepartment of Pharmacy and Biotechnology, University of Bologna, 40126 Bologna, ItalyDepartment of Pharmacy and Biotechnology, University of Bologna, 40126 Bologna, ItalyDepartment of Pharmacy and Biotechnology, University of Bologna, 40126 Bologna, ItalyParvovirus B19 (B19V), an ssDNA virus in the family Parvoviridae, is a human pathogenic virus, responsible for a wide range of clinical manifestations, still in need of effective and specific antivirals. DNA structures, including G-quadruplex (G4), have been recognised as relevant functional features in viral genomes, and small-molecule ligands binding to these structures are promising antiviral compounds. Bioinformatic tools predict the presence of potential G4 forming sequences (PQSs) in the genome of B19V, raising interest as targets for antiviral strategies. Predictions locate PQSs in the genomic terminal regions, in proximity to replicative origins. The actual propensity of these PQSs to form G4 structures was investigated by circular dichroism spectroscopic analysis on synthetic oligonucleotides of corresponding sequences. No signature of G4 structures was detected, and the interaction with the G4 ligand BRACO-19 (<i>N</i>,<i>N</i>′-(9-{[4-(dimethylamino)phenyl]amino}acridine-3,6-diyl)bis(3-pyrrolidin-1-ylpropanamide) did not appear consistent with the stabilisation of G4 structures. Any potential role of PQSs in the viral lifecycle was then assessed in an in vitro infection model system, by evaluating any variation in replication or expression of B19V in the presence of the G4 ligands BRACO-19 and pyridostatin. Neither showed a significant inhibitory activity on B19V replication or expression. Experimental challenge did not support bioinformatic predictions. The terminal regions of B19V are characterised by relevant sequence and symmetry constraints, which are functional to viral replication. Our experiments suggest that these impose a stringent requirement prevailing over the propensity of forming actual G4 structures.https://www.mdpi.com/1999-4915/12/9/935parvovirus B19G-quadruplexbioinformaticsantiviralsBRACO-19pyridostatin |
| spellingShingle | Gloria Bua Daniele Tedesco Ilaria Conti Alessandro Reggiani Manuela Bartolini Giorgio Gallinella No G-Quadruplex Structures in the DNA of Parvovirus B19: Experimental Evidence versus Bioinformatic Predictions Viruses parvovirus B19 G-quadruplex bioinformatics antivirals BRACO-19 pyridostatin |
| title | No G-Quadruplex Structures in the DNA of Parvovirus B19: Experimental Evidence versus Bioinformatic Predictions |
| title_full | No G-Quadruplex Structures in the DNA of Parvovirus B19: Experimental Evidence versus Bioinformatic Predictions |
| title_fullStr | No G-Quadruplex Structures in the DNA of Parvovirus B19: Experimental Evidence versus Bioinformatic Predictions |
| title_full_unstemmed | No G-Quadruplex Structures in the DNA of Parvovirus B19: Experimental Evidence versus Bioinformatic Predictions |
| title_short | No G-Quadruplex Structures in the DNA of Parvovirus B19: Experimental Evidence versus Bioinformatic Predictions |
| title_sort | no g quadruplex structures in the dna of parvovirus b19 experimental evidence versus bioinformatic predictions |
| topic | parvovirus B19 G-quadruplex bioinformatics antivirals BRACO-19 pyridostatin |
| url | https://www.mdpi.com/1999-4915/12/9/935 |
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