4.5 The use of nucleic acids as targeting agents
We have already described how catalytic functions such as backbone cleavage found in ribozymes can be harnessed to target destruction of specific RNAs and how hybridisation techniques are used to identify nucleic acids. In this section, we will examine two other applications of nucleic acids that depend upon their ability to base-pair and to form a wide range of secondary structures, namely antisense regulation of gene expression and the use of aptamers as structure-specific reagents.