Advances in hairpin ribozyme design for gene therapy

Includes bibliographical references (pages [44]-45)Use of catalytic RNAs (ribozymes) as anti-viral therapeutics is currently being studied by several laboratories. The hairpin ribozyme has been designed to target HIV-1 and it is currently being optimized for use in gene therapy. Improvements have been made in both the method of delivery and in the molecular structure of the ribozyme molecule. We have altered the original retroviral vector so that it now contains multiple anti-viral sequences. This type of vector design allows for targeting the HIV-1 virus at more than one site in its genome. It also makes it possible to deliver ribozyme and anti-sense sequences simultaneously. Structural modifications made to the ribozyme molecule have involved the addition of a tetraloop sequence to helix 3 and loop 4 of the original native structure. This modification has been shown to increase the activity and the temperature stability of several hairpin ribozymes. A second modification was the addition of a tRNA like structure from Brome Mosaic Virus (BMV) to the 3' terminus of the ribozyme. This addition to the ribozyme has been shown to increase stability in vitro while maintaining ribozyme activity.M.S. (Master of Science