Peptide nucleic acid (PNA) is a hybrid compound with nucleoside bases linked to a peptide-like amide backbone. PNA is capable
of sequence-specific base pairing and forms highly stable double and triple helices with natural nucleic acids (DNA, RNA).
PNA forms stable hydrogen bonds and is resistant to degradation by nudeases and proteases. Because of these physicochemical
properties, PNA has attracted great attention, since its first description in 1991, as a potential gene-specific drug and
a versatile molecular biology tool. More and more laboratories are working with PNA and the number of applications in which
PNA proves useful continues to increase.
In this chapter, we describe aspects of the biochemistry of peptide nucleic acids and their use as a molecular biology reagent,
and then focus on the antisense and anti-gene activity of PNA, with special reference to studies of medical interest, in particular
in the PML/RARα and the bcl-2 systems.