RNase A catalyzes the transphosphorylation and degradation of RNA. It was the first protein identified to exhibit DNA melting functionality. This enzyme binds to several binding sites on single stranded (ss) RNA polynucleotide chain before degrading it. It interacts with ssDNA in a similar manner, which is responsible for its ‘DNA unwinding’ property. RNase A dimer obtained through tandemization shows toxicity to cancer cells.