Enzymatic RNA molecules, or ribozymes, offer access to genotypic and phenotypic information in the laboratory.
The unexpected discovery that the RNA molecule has catalytic properties has led to a plethora of interest in the identification and utilization of the variety of catalytic RNA molecules, or ribozymes, that occur in nature.
It serves as a template for translation of a sequence into protein but also serves many other functions in the cell, for example as an enzyme (aka ribozyme), regulatory molecule, or as a part of the ribosome.
Among these delivery systems, liposomes represent a promising technology for the delivery of macromolecules into cells for the following reasons: (1) they are non-cytotoxic; (2), they can deliver and specifically target a large set of bioactive molecules (such as proteins, DNA or ribozymes); (3), they can protect molecules from degradation; and (4), their composition is easily modifiable.
To this end, an anti-U5 hammerhead ribozyme, engineered as a hybrid small adenoviral VAI RNA (VAIα), was inserted into the vector as a single molecule or in combination with the double copy anti-tat sequence.
For example, montmorillonite particles have been shown to protect catalytic RNA molecules (hairpin ribozyme 1) from UV-induced damage: after a UV-irradiation, the self-cleavage activity of the montmorillonite-adsorbed ribozyme molecules was three times higher compared to that of the molecules irradiated in the absence of montmorillonite [ 168].
We engineered small molecule responsive allosteric ribozymes based on the genomic hepatitis delta virus (HDV) ribozyme by replacing the P4-L4 stem-loop with an RNA aptamer through a connector stem.
Fig. 15 The general procedure for the in vitro selection of aptamers or ribozymes.
The multiple subunit structure of the spliceosome has implications for the regulation of a splicing event and for its possible catalysis by ribozyme or ribozymes.
They are often called "replicases" or ribozymes as a result of this dual ability to replicate and catalyze.
