DIG 3′-End Oligonucleotide Labeling Kit with Digoxigenin-11-ddUTP

DIG 3′-End Oligonucleotide Labeling Kit with Digoxigenin-11-ddUTP contains all reagents (except oligonucleotide template to be labeled and materials for Digoxigenin detection) required for efficient 3′-End digoxigenylation of DNA oligonucleotides (length: 20 -100 bp, 5 pmol per reaction). The labeling principle is based on Terminal deoxynucleotidyl Transferase (TdT) that template-independently transfers 1 Digoxigenin-11-ddUTP to the 3′-OH group of ssDNA (e.g. an oligonucleotide) in the presence of CoCl2. It is similar to the principle of DIG Oligonucleotide 3′-End DNA Labeling Kit, 2nd Generation (Roche). The resulting 3′-End digoxigenylated oligonucleotides are ideally suited for applications involving sequence-specific protein binding or hybridiziation such as EMSA, Northern or Southern blots. Compared to internal, random digoxigenylated probes, Digoxigenin is located at the 3′-End only and less likely interferes with probe binding. TdT possesses a preference for single-stranded DNA (ssDNA) over dsDNA with 3′-overhangs or blunt ends. For the preparation of labeled dsDNA complexes, label each complementary oligonucleotide separately and anneal them before use.