DNA nucleotidylexotransferase (DNTT)

Template-independent DNA polymerase which catalyzes the random inclusion of deoxynucleoside 5'-triphosphate into the 3'-end of a DNA initiator. One of the in vivo functions of the enzyme is that the addition of nucleotides at the junction (N region) of rearranged Ig heavy chain and T-cell receptor gene segments during the maturation of B- and T-cells.

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