Antisense Methods in Cell Culture

Abstract

The notion of using specific oligonucleotides for the modulation of gene expression surfaced nearly two decades ago when DNA oligonucleotides were used to inhibit Rous sarcoma virus replication and cell transformation (Zamenick 1978). The basic idea behind the use of antisense molecules is quite simple. An oligonucleotide chain containing bases complementary to a given target (sense) sequence can bind to this target sequence, and thus inhibit its processing, through the interactions defined by the Watson and Crick base pairing rules. These rules state that a guanosine must always base pair with a cytosine, while a tyrosine must base pair with an adenosine. Thus, once the sequence of a target gene is known, an antisense molecule can be designed which specifically binds to this gene alone. The initial antisense molecules were oligodeoxynucleotide sequences targeted to mRNA molecules. However, recent advances in molecular biology have widened the spectrum of antisense compounds to include RNA oligos targeted against RNA, DNA oligos targeted against DNA (termed antigenes) and either DNA or RNA oligos which bind to and inhibit the function of peptides and proteins (termed aptamers) (for reviews see Ma and Calvo 1996; Scanlon et al. 1995; Wagner 1994, 1995; Zhang 1996).