Caister Academic Press

TA Cloning

TA Cloning uses the terminal transferase activity of some DNA polymerases. In TA Cloning Taq polymerase adds a 3'-A overhang to each end of the PCR product. TA Cloning makes it possible to clone the PCR product into a cloning vector with 3'-T overhangs. TA Cloning is widely used in molecular biology.
Epigenetics: Current Research and Emerging Trends
Edited by: Brian P. Chadwick
"this is one text you don't want to miss" (Epigenie); "up-to-date information" (ChemMedChem)

TA Cloning

TA Cloning exploits the terminal transferase activity of some DNA polymerases. In TA Cloning Taq polymerase adds a 3'-A overhang to each end of the PCR product. TA Cloning makes it possible to clone the PCR product into a cloning vector with 3'-T overhangs. During TA Cloning the PCR products with dA overhang are mixed in high proportion with the vector. The complementary overhangs of T vector and PCR product are then ligated using T4 DNA ligase.

"TA cloning" is a popular method of cloning without the use of restriction enzymes; instead, PCR products are amplified with only Taq DNA polymerase and other polymerases. These polymerases lack 5'-3' proofreading activity and add an adenosine triphosphate residue to the 3' ends of the double-stranded PCR products. Such PCR amplified products can thus be cloned in a linearized vector that has complementary 3' thymidine triphosphate overhangs.

A recently described Quick Assemble PCR cloning protocol has been used to improve TA cloning. The new 2-day PCR-based method can be used to generate both circularized and linear final assembled products. The protocol circumvents the use of DNA ligase. The PCR-based protocol uses a TA cloning vector as the template for the linear vector backbone demonstrating the ability to improve this technique.

from Zuo and Rabie in Curr. Issues Mol. Biol. 12: 11-16