Dataset Information

Thermodynamic and structural contributions of the 6-thioguanosine residue to helical properties of RNA.

ABSTRACT: Thionucleotides, especially 4-thiouridine and 6-thioguanosine, are photosensitive molecules that photocrosslink to both proteins and nucleic acids, and this feature is a major reason for their application in various investigations. To get insight into the thermodynamic and structural contributions of 6-thioguanosine to the properties of RNA duplexes a systematic study was performed. In a series of RNA duplexes, selected guanosine residues located in G-C base pairs, mismatches (G-G, G-U, and G-A), or 5' and 3'-dangling ends were replaced with 6-thioguanosine. Generally, the presence of 6-thioguanosine diminishes the thermodynamic stability of RNA duplexes. This effect depends on its position within duplexes and the sequence of adjacent base pairs. However, when placed at a dangling end a 6-thioguanosine residue actually exerts a weak stabilizing effect. Furthermore, the structural effect of 6-thioguanosine substitution appears to be minimal based on NMR and Circular Dichroism (CD) data.

SUBMITTER: Gladysz M

PROVIDER: S-EPMC6416399 | biostudies-literature | 2019 Mar

REPOSITORIES: biostudies-literature

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Thermodynamic and structural contributions of the 6-thioguanosine residue to helical properties of RNA.

Gładysz Michał M Andrałojć Witold W Czapik Tomasz T Gdaniec Zofia Z Kierzek Ryszard R

Scientific reports 20190313 1

Thionucleotides, especially 4-thiouridine and 6-thioguanosine, are photosensitive molecules that photocrosslink to both proteins and nucleic acids, and this feature is a major reason for their application in various investigations. To get insight into the thermodynamic and structural contributions of 6-thioguanosine to the properties of RNA duplexes a systematic study was performed. In a series of RNA duplexes, selected guanosine residues located in G-C base pairs, mismatches (G-G, G-U, and G-A) ...[more]

PMID: 30867505

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Dataset Information

Thermodynamic and structural contributions of the 6-thioguanosine residue to helical properties of RNA.

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Thermodynamic and structural contributions of the 6-thioguanosine residue to helical properties of RNA.

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