Metal ion-dependent hydrolysis of RNA phosphodiester bonds within hairpin loops. A comparative kinetic study on chimeric ribo/2'-O-methylribo oligonucleotides.
Nucleic Acids Res
; 26(14): 3392-6, 1998 Jul 15.
Article
en En
| MEDLINE
| ID: mdl-9649624
ABSTRACT
Several chimeric ribo/2'- O -methylribo oligonucleotides were synthesized and their hydrolytic cleavage studied in the presence of Mg2+, Zn2+, Pb2+and the 1,4,9-triaza-cyclododecane chelate of Zn2+(Zn2+[12]aneN3) to evaluate the importance of RNA secondary structure as a factor determining the reactivity of phosphodiester bonds. In all the cases studied, a phosphodiester bond within a 4-7 nt loop was hydrolytically more stable than a similar bond within a linear single strand, but markedly less stable than that in a double helix. With Zn2+and Zn2+[12]aneN3, the hydrolytic stability of a phosphodiester bond within a hairpin loop gradually decreased on increasing the distance from the stem. A similar but less systematic trend was observed with Pb2+. Zn2+- and Pb2+-promoted cleavage was observed to be considerably more sensitive to the secondary structure of the chain than that induced by Zn2+[12]aneN3. This difference in behaviour may be attributed to bidentate binding of uncomplexed aquo ions to two different phosphodiester bonds. Mg2+was observed to be catalytically virtually inactive compared with the other cleaving agents studied.
Texto completo:
1
Colección:
01-internacional
Base de datos:
MEDLINE
Asunto principal:
Oligonucleótidos
/
Zinc
/
ARN
/
Conformación de Ácido Nucleico
Idioma:
En
Revista:
Nucleic Acids Res
Año:
1998
Tipo del documento:
Article
País de afiliación:
Finlandia