Ribozymes, a new therapeutic strategy?

Abstract

Ribozymes are RNA molecules endowed with catalytic activity, they are able to cataIyze chemical reactions inside the cells. In their natural environment, most of the described ribozymes carry out processing of other RNA molecule. In contrast to the protein ribonucleases, ribozymes exhibit a high-substrate specificity. This feature is the base for the potential use of ribozymes as specific gene suppressors and therefore to develop new therapeutic agents. The need of new therapeutic strategies is even more significant with the rising of diseases against which the existent drugs and therapies do not show the desirable efficiency. The social repercussions of some diseases of difficult or low probability of control (AIDS, Cancer, etc.), has made more acute the need of looking for altemative treatments. Among the experimental approaches that are being carried out is the direct action on the genetic information responsible of such diseases. On this line, several strategies have emerged in the past few years, mainly based on the use of nucleic acids as specific gene suppressors, e.g. antisense oligonucleotides, ribozymes and triplex helix. The ribozymes would act blocking the transmission of genetic information at the RNA level, mediating destruction of RNA genomes (RNA virus) or mRNAs. A deep understanding of the mechanisms used by these molecules for the recognition and interaction with their RNA substrates as well as of these molecules themselves is necessary for the design and effective application of ribozymes with new specificity. In this work we describe the best characterized catalytic RNAs, as well as the different strategies developed for their use as gene tic suppressors.