The effect of the neutral cytidine protonated analogue pseudoisocytidine on the stability of i-motif structures

Incorporation of pseudoisocytidine (psC), a neutral analogue of protonated cytidine, in i-motifs has been studied by spectroscopic methods. Our results show that neutral psC:C base pairs can stabilize i-motifs at neutral pH, but the stabilization only occurs when psC:C base pairs are located at the...

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Detalles Bibliográficos
Autores: Mir Morro, Bartomeu, Solés, X., González, Carlos, Escaja Sánchez, Nuria
Tipo de recurso: artículo
Estado:Versión publicada
Fecha de publicación:2017
País:España
Institución:Universidad de Barcelona
Repositorio:Dipòsit Digital de la UB
OAI Identifier:oai:diposit.ub.edu:2445/112375
Acceso en línea:https://hdl.handle.net/2445/112375
Access Level:acceso abierto
Palabra clave:Àcids nucleics
Citidina difosfat de colina
Oligonucleòtids
Nucleic acids
Cytidine diphosphate choline
Oligonucleotides
Descripción
Sumario:Incorporation of pseudoisocytidine (psC), a neutral analogue of protonated cytidine, in i-motifs has been studied by spectroscopic methods. Our results show that neutral psC:C base pairs can stabilize i-motifs at neutral pH, but the stabilization only occurs when psC:C base pairs are located at the ends of intercalated C:C+ stacks. When psC occupies central positions, the resulting i-motifs are only observed at low pH and psC:C+ or psC:psC+ hemiprotonated base pairs are formed instead of their neutral analogs. Overall, our results suggest that positively charged base pairs are necessary to stabilize this non-canonical DNA structure.