Terminal deoxytransferase

Desiderio, S.V., Yancopoulos, G.D., Paskind, M., Thomas, E., Boss, M.A., Landau, N., Alt, F.W., Baltimore, D. (1984). Insertion of N regions into heavy-chain genes is correlated with expression of terminal deoxytransferase in B cells. Nature 311,752-755. 

Another common method for measuring apoptosis is the DNA labeling technique, terminal deoxytransferase-mediated dUTP nick-end labeling (TUNEL). In this method, labeling of DNA strand breaks at the 3 end is achieved by using the enzyme, terminal deoxynucleotidyl transferase (TdT) and either a radioactive or a fluorescently-Iabeled deoxynucleotide. This method provides a very sensitive measurement of DNA strands breaks. However, as DNA strand... 

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