title: Evaluation of different types of end-capping modifications on the stability of oligonucleotides toward 3'- and 5'-exonucleases.
abstract: Synthetic oligonucleotides are increasingly used because of their potential activity as regulators of gene expression. One of their major drawbacks is instability toward nucleases, in particular exonucleases. In this article, we studied some terminal modifications that can enhance exonuclease resistance, such as end-capping with alkylic chains (1,3-propanediol and 1,6-hexanediol), and with a modified nucleotide (2',3'-secouridine). These compounds were compared with the parent (natural) oligodeoxynucleotide and with different analogs containing a progressive number of phosphorothioate linkages. The resistance toward SVPDE and CSPDE (a 3'- and a 5'-exonuclease) was assessed, in vitro, by two independent techniques, UV and HPLC. Our results showed that the stability of all the modified oligonucleotides was at least 12 times that of the parent compound.
authors.affiliation: ICOCEA-CNR, Bologna, Italy.
authors.forename: D
authors.initials: D
authors.lastname: Pandolfi
authors.forename: F
authors.initials: F
authors.lastname: Rauzi
authors.forename: M L
authors.initials: ML
authors.lastname: Capobianco
mesh_terms: D000818:Animals; D002417:Cattle; D002851:Chromatography, High Pressure Liquid; D005092:Exonucleases / Q000378:metabolism*; D005786:Gene Expression Regulation; D006018:Glycols / Q000737:chemistry; D009682:Magnetic Resonance Spectroscopy; D009691:Nucleic Acid Denaturation; D009838:Oligodeoxyribonucleotides / Q000138:chemical synthesis*; D016376:Oligonucleotides, Antisense / Q000138:chemical synthesis; D009843:Oligoribonucleotides / Q000737:chemistry; D043264:Phosphodiesterase I; D010727:Phosphoric Diester Hydrolases / Q000378:metabolism*; D011409:Propylene Glycols / Q000737:chemistry; D012910:Snake Venoms / Q000201:enzymology; D013056:Spectrophotometry, Ultraviolet; D013154:Spleen / Q000201:enzymology; D014529:Uridine / Q000031:analogs & derivatives
chemical_list: D006018:Glycols; D009838:Oligodeoxyribonucleotides; D016376:Oligonucleotides, Antisense; D009843:Oligoribonucleotides; D011409:Propylene Glycols; D012910:Snake Venoms; C041787:1,3-propanediol; D005092:Exonucleases; C022650:spleen exonuclease; D010727:Phosphoric Diester Hydrolases; D043264:Phosphodiesterase I; C470790:phosphodiesterase I, snake venom; D014529:Uridine; C027765:hexamethylene glycol