Synthesis, Thermodynamic Properties, and Crystal Structure of RNA Oligonucleotides Containing 5-Hydroxymethylcytosine.
Fiche publication
Date publication
août 2017
Journal
The Journal of organic chemistry
Auteurs
Membres identifiés du Cancéropôle Est :
Dr ENNIFAR Eric
Tous les auteurs :
Riml C, Lusser A, Ennifar E, Micura R
Lien Pubmed
Résumé
5-Hydroxymethylcytosine (hmC) is an RNA modification that has attracted significant interest because of the finding that RNA hydroxymethylation can favor mRNA translation. For insight into the mechanistic details of hmC function to be obtained, the availability of RNAs containing this modification at defined positions that can be used for in vitro studies is highly desirable. In this work, we present an eight-step route to 5-hydroxymethylcytidine (hmrC) phosphoramidite for solid-phase synthesis of modified RNA oligonucleotides. Furthermore, we examined the effects of hmrC on RNA duplex stability and its impact on structure formation using the sarcin-ricin loop (SRL) motif. Thermal denaturation experiments revealed that hmrC increases RNA duplex stability. By contrast, when cytosine within an UNCG tetraloop motif was replaced by hmrC, the thermodynamic stability of the corresponding hairpin fold was attenuated. Importantly, incorporation of hmrC into the SRL motif resulted in an RNA crystal structure at 0.85 Å resolution. Besides changes in the hydration pattern at the site of modification, a slight opening of the hmrC-G pair compared to the unmodified C-G in the native structure was revealed.
Mots clés
5-Methylcytosine, analogs & derivatives, Carbohydrate Conformation, Crystallography, X-Ray, Models, Molecular, Oligonucleotides, chemistry, RNA, chemistry, Thermodynamics
Référence
J. Org. Chem.. 2017 Aug 4;82(15):7939-7945