IN VITRO SELECTION OF ADENINE DEPENDENT RIBOZYMES

摘要

One of the problems of the RNA world scenario is the lack of RNA functional groups which leads to the poor catalytic repertoire of ribozymes compared to proteins. To increase RNA functionalities, ribozymes can bind small exogenous reactive molecules, and handle them to help catalysis. We hypothesize that the current role of histidine in protein catalysis was performed by adenine in primeval catalysts and that RNA world ribozymes could have bound free adenine and handled it to catalyze chemical reactions. In order to test the likelihood of such a scenario, we are selecting in vitro adenine-dependent ribozymes from a population of hairpin variant ribozymes randomized in 15-20 critical positions. The study of such ribozymes could bring information about the hairpin catalytic mechanism and have evolutionary implications in our vision of the prebiotic RNA world.