DIG-UTP

Some of these reactions can also be used for non-radioactive labelling (Isaac 1994) since Tag-polymerase, DNA polymerase I and also terminal transferase can accept compounds such as digoxygenin-dUTP (DIG-dUTP) and the dideoxy derivative DIG-ddUTP as substrates. DIG-labelled DNA can be detected colorimetrically by antibodies coupled to peroxidase using chromogenic substrates. Similar procedures can also be used to label RNA using DIG-UTP with T7- or SP6-RNA polymerases. Digoxygenin labelling kits are commercially available. 

Dig-UTP (BMB) is a UTP analog containing a steroid hapten isolated from Foxglove plants. In the Dig-UTP molecule, digoxigenin is coupled to the C-5 of uracil via an 11-atom spacer arm. Because of the bulky size of the Dig molecule, Dig-UTP labeling of some transcripts is more efficiently performed at a Dig-UTP/ UTP ratio of 0.15/0.85 instead of the usual 0.35/0.65. Dig-labeled probes/products can be detected or quantitated in situ or on membranes by means of an anti-Dig antibody coupled with a reporter enzyme (e.g., alkaline phosphatase) and of the enzymatic reaction with chromogenic or (chemi)luminescent substrates. 

Synthesis of Digoxygenin (DIG) or Fluorescein-12 UTP (FITC) Labeled Riboprobes... 

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