In vitro selection of ligase ribozymes containing 2 '-amino groups

Novel ribozymes containing 2'-amino groups in the side chains were in vitro selected to accelerate their ligation reaction rates with oligodeoxynucleo tides. The ligation rate of random sequenced RNAs in the starting pool was accelerated by incorporation of 2'-amino-2'-deoxyuridine and N-6-(6-aminohe xyl)adenosine. The incorporation of the amino group enhanced the activity o f non-selected RNAs independent of the incorporation site. In. vitro select ion using 2'-amino-2'-deoxyuridine instead of uridine produced more active ribozymes. In this case, the activity of ribozyme was reduced when N-6-(6-a minohexyl)adenosine was incorporated into the selected RNAs instead of natu ral adenosine. The presence of amino groups as well as the incorporation si te affected the activity of the in vitro selected ribozyme. It seems that R NAs with tertiary structures suitable for the ligation reaction were select ed by the in vitro method.