Poly(A) Polymerase, Yeast

Poly(A) Polymerase, Yeast catalyses the template independent addition of adenosine residues onto the 3' ends of polyribonucleotides. The use of ATP as a substrate leads to poly(A) tailing whereas substitution of cordycepin-5'-triphosphate (3'-dATP) for ATP results in addition of a single dA residue to the 3’-termini of the RNA. Neither ADP nor dATP can be used as substrates for this enzyme. Poly(A) Polymerase from yeast has been shown to be more effective at oligonucleotide-labeling and poly(A) tailing of long RNA templates than Poly(A) Polymerase from <i>E. coli</i>.