Modified RNA sequence pools forin vitroselection

Abstract
We report the use of modified RNA, In which the 2′-OH group of pyrimldlnes is replaced by a 2′-amino (2′-NH2) group to Identify high affinity ligands specific for human neutrophll elastase (HNE) by In vitro selection. Compared to unmodified RNA the 2'-NH2-modified RNA ligands show enhanced stability in human serum and urine. Use of RNase T1 cleavage data in the presence of K+ and LI + ions suggests that the modified RNA ligands selected for HNE form an intermolecular G-quartet structure.