Favorable 2'-substitution in the loop region of a thrombin-binding DNA aptamer

Abstract

Simple 2'-OMe-chemical modification in the loop region of the 15mer G-rich DNA sequence GGTTGGTGTGGTTGG is reported. The G-quadruplex structure of this thrombin-binding aptamer (TBA), is stabilized by single modifications (T → 2'-OMe-U), depending on the position of the modification. The structural stability also renders significantly increased inhibition of thrombin-induced fibrin polymerization, a process closely associated with blood-clotting.

Keywords: 2′-O-methyl ribo-uridine; Fibrin polymerization; G-quadruplex; Thrombin binding aptamer; Thrombin time.