Detecting mRNA with Base Pairing: Part 2

For visualization, the probe was tagged with a molecule that can be selectively recognized by an antibody. A useful tag molecule is digoxigenin (DIG), which only occurs in the foxglove plant.

In all other biological material, an anti-DIG antibody will bind only to the tag molecule, providing a clear signal.

Chick embryo on the left; the right shows a blue strand labeled Probe over a purple ribbon labeled R-N-A of interest. To the right of the probe is a blue shape labeled tag molecule (DIG) and a red Y shape next to it labeled Anti-DIG antibody.
Anti-DIG antibody binds to probe with tag molecule (DIG)